TurquoiseEnergyLtd.News#86 March 2015 (posted April 3rd)

Victoria BCby Craig Carmichael

www.TurquoiseEnergy.com=www.ElectricCaik.com=www.ElectricHubcap.com=www.ElectricWeel.com

Highlights:* A new design concept for an add-on wheel motor system (see Month in Brief)* Porous nickel sheet and powder for nickel battery electrode (see Month in Brief, Electricity Storage)

Month In Brief (Project Summaries) - Aquaponics & LED Lighting Progress - 'Ultra efficient' Electric Chevy Sprint project to be resumed - Axial FluxSwitched Reluctance Motor (AFSRM, replacing unipolar motor) - Add On Wheel Motor: a New System Design - AFSRMGenerator for Windplants et al - Electric Weel Generator - My/R & D finances? - The Usual Mazda Batteries Update -Turquoise Battery Project: Ni-Ni battery production ideas, great new nickel negode idea!

In Passing (Miscellaneous topics, editorial comments & opinionated rants) - Ceres, Vesta and Vegetation - Unsustainable World Population

Electric Transport - Electric Hubcap Motor Systems* 'On hold' Chevy Sprint Electric Hubcap/Planetary gear torque converter & Centrifugal clutch is to be completed.* Electric Caik Axial Flux Switched Reluctance Motor - AFSRM (was unipolar motor)* Active Reluctance Generators: no cogging and output voltage regulation!* A Switched Reluctance EV Motor by Ricardo.com (85KW!), AFSRM design papers* Electric Weel - Huge low RPM generator [at last] nears completion

Other "Green" Electric Equipment Projects* Aquaponics & LED Grow Lighting - tilapia pool - Beans?!?* Cordless Lawnmower with NiMH dry cells: User Review

Electricity Generation (No reports)

Electricity Storage - Turquoise Battery Project (NiMn, NiNi), etc.* Cylindrical cells with carbon rods?* Ni-Zn or Ni-Ni acid battery with oxalic acid?* Ni-Ni cell with nickel-brass sheet for negode?* To make porous nickel sheets and porous nickel powder! (from nickel-brass sheet and monel powder)* Packing peanuts for carbon film, carbon nano-particles?

No Project Reports on: Variable Torque Converter Transmission, Magnet motor, Lambda ray collector, evacuated tube heat radiators, CNCgardening/farming machine.

MarchinBriefAquaponics & LED Lighting Progress

I spent the early days of the month digging andworking on a 'trench' pond in the garden for thetilapia. it looked like it would be in the way ofaccess wherever I dug it, then I got the idea to puta bridge across it. So far that's just a fat plank.There wasn't much extra pond liner, and Isandwiched the edges between boards to keep itfrom drooping down. The building supply ran outof 8x16" paving blocks, and I bought some cementand sand and made some larger, thicker ones ofmy own. I may get around to a second batch sometime.

The water was too cold for tilapia, and I went toa pet shop and got a dozen goldfish to keep anymosquito wrigglers out of the water. (But it'sprobably too cold for them too.) I got someduckweed and put it on top, and when there'ssurplus I can take it in and feed it to the tilapia -goldfish don't eat it.

Inside, the beans in the aquaponics drain-downbed continued to grow, hitting the ceiling andblocking most of the light from the window. Oneflower appeared for a couple of days and thenwilted, with no more appearing. The beans werejust one of a number of things I planted in therelast fall, but they overgrew everything else andprevented any other crop. I certainly won't trygrowing beans in indoor aquaponics again unless Ifind out why they're not producing beans. The tilapia fish also continued to grow. The largefemale was almost 12" long in a 12x12x12" space.They will certainly want that (~400 liter) trenchpond once it warms up and I get the bedsconnected and a pump running. The little one was2-1/2" long by month end.

I didn't do anything with LED lighting exceptdecide that a switching regulator would give a lotmore flexibility and perform better than the linearone, except with certain combinations of voltagesand emitters which weren't nearly as much "thenorm" as I expected them to be before making andusing a few lights with the varying solarpanel/battery system voltages. (And I was soproud of my minimal components constant currentlinear regulator circuit!)

Axial Flux Switched Reluctance Motor (AFSRM)

Out of sequence, I'll mention that it now looks like the AFSRM project now looks like it will stretch out a fewmonths. The motor, while very doable, is also very different from the BLDC magnet motor, so there'll be a lot of newdesign. That suggests it might be a good idea to complete the current version car drive first. It's all been sittingnearly assembled and ready to install and try out in the car. It's worth completing it and seeing if I've finally found aworkable path to a high-efficiency vehicle drive.

The "switched reluctance" or "SR" type of motorseemed to have all the advantages of the bipolar(or unipolar) BLDC types, would use the samemotor controller as I had just made for theunipolar, and had reduced weight, cost and rotorthickness, plus greatly increased RPM capabilitycompared with my rotors with magnets. By about the end of February I made up mymind to convert the new Electric Caik motor fromunipolar to the SR type. The only differencesseemed to be the rotor and perhaps a few statorwiring changes. The apparent similarity proved tobe deceptive. After thinking about it while working on thetilapia pond, on the 12th and 13th I designed arotor that I hoped would have a relatively low levelof torque ripple, that being said to be the worstfeature of the reluctance type of motor. Later acorrespondent pointed out that the main reasonfor the high torque ripple compared to BLDCmagnet motors is that the SR coils can only pullsteel, not repel it, so more poles are needed to getequivalent evenness of forces. The rotor had the aspect of an "iron cross" witha circular outside edge, and I made it by cuttingout the four sections between the four "lobes"from a ready-made "brake rotor disk", cast from"soft magnetic" metal - that wouldn't magnetizewhen rubbed with a supermagnet. The crosssection "sort of" followed the curves of the roundcoil cores.

It felt quite different installing a thin, magnetless rotor that didn't try to grab tools off the bench and suck itself intothe motor unbidden while your fingers were still under it. And once it was on, it didn't try to cog to different positions.Only the friction of the grease-stuffed bearings kept it from freely spinning. It also didn't turn, with 10 amps of current. The magnetic forces were too weak. The sort of huge flux gaps andplenty of flux for a relaxed BLDC design is replaced in the SR type by tiny gaps and a struggle to find enough flux fordecent torque. It needed a wholely different design and layout.

So I took two coils, the rotor and the labpower supply to deliver a constant 10 ampsto the coils, and started doing someelectromagnetic experiments on the benchto maximize the forces. These pointed tobetter ways to go, and I made modificationsthat should get things working. A steel platebehind the coils works to complete the fluxcircuit. Then someone suggested using tworotors, one on each side of the stator, todouble the flux. This seemed like a goodplan. I also thought of putting a ring ofmetal around the outside rim of each'donut' coil to concentrate the flux like in acup magnet, where a weak ceramic magnethas "supermagnet" levels of flux in thesmall space between the round magnet andthe rim surrounding it.

Acupmagnet

Although I got the metal, I hadn't found a heavy sheet metal shear to cut it into 1" strips by month's end. (Tin snipsdo an ugly job.)

Then in the latter part of the month it occurred to me to do a web search, and I found two technical papers (PDF.s)describing axial flux switched reluctance motors (AFSRM.s). It turns out that the axial flux SRM layout is indeed much superior to radial flux, but for different reasons than withBLDC magnet motors. The flat rotors and coils with a flat profile can have substantially larger adjacent surface areasfor flux interaction. Also, the usual two rotors with the stator between them virtually doubles the forces available withthe same current. With the right designs, levels of torque can be attained that will move vehicles by direct drive, forin-wheel motors as small as 12" diameter. Such motors are however pretty heavy for good vehicle suspension

handling. I plan to finish my small "AFSRM" as conceived and test it out, along with the motor controller, which luckily is thesame one as for the unipolar magnet motor, that I designed and made earlier this year. But the next and largerdesign for a car motor should probably be more along the lines of the test motor built and tested in the JapaneseAFSRM design paper.

Along the way I made a balanced "arm" to measure static "locked rotor" torque, in conjunction with a weigh scale.(After shaping the pointer, I cut and ground metal off an "L" piece at the far end until it balanced.) It'll be far moresensitive than a torque wrench. The "pointer" that presses on the scale is exactly 6.0" from the center of the shaft, soit's easy to convert the "weight" measured into foot-pounds.

Add On Wheel Motor: a New System Design

Also along the way, I've conceived what I think should be a good solution to large and heavy in-wheel motors, asproposed in the two papers and many other places. Placing an SRM directly on a wheel's axle where its RPM is limitedto the low speed of the wheel, is a waste of one of its big advantages - the ability to run well and safely at highRPM.s. A motor running at 0-5000 RPM will be much smaller and lighter to get the same power as one running at 0-1000 RPM connected directly to a car wheel. With 1/5 the torque it is geared down with a fixed ratio, eg 7 to 1, todeliver sufficient car-starting torque, and because over-revving for this motor probably means (say) around 10000RPM or higher, 7000 RPM on the highway is fine. The rotors spinning at such high speeds are (as I envision them)solid pieces of steel that won't fly apart, and fairly light as steel rotors go. That means no variable torque converter,clutch, or gear shifting is needed. And that leads to major simplifications. The first type of gear reduction that came to mind was a large planetary gear, perhaps with plastic 'planet' gears toeliminate lubrication requirements. The motor would be as originally conceived, in the "hubcap" position, bouncing upand down with the wheel, probably with some flexible coupling making for some level of "debounce".

Then a solution that seems superior came to me. The "on wheel" or "in wheel" motor is conceptually elegant, butthen one hits bumps in the road, which are more easily dealt with without a considerable extra weight on the wheel.One solution that's been used is to mount the "wheel" motor within the vehicle. Drive shafts with CV joints thenconnect it to the wheel. My plan, for rear wheel drive only, is (AFAIK) new as applied to cars: For an outside "add-on" electric pancakemotor mounting, a telescoping 'arm' runs from the center of the wheel to somewhere on the car body, either in frontof or behind the wheel, about level with it. (sketch below) The wheel end of the arm moves with the wheel as itbounces up and down with bumps. But the body end is almost stationary. The telescoping or flex mounting pieceattached to the car body to allow the arm to move with the wheel is very short. (Probably with more than oneattachment point for support against twisting.) The smaller, lighter motor is mounted on the arm, near the body end. It doesn't move around very much, thus itwill have little effect on suspension handling. But being on the arm which is connected with a bearing et al to the hubof the wheel, its position relative to the hub of the wheel is fixed. It is then necessary only to connect the motor tothe wheel with an efficient drive belt: toothed, flat or poly-V, with pulleys sized to give the desired reduction. And thepulleys can easily be changed to see what reduction ratio works best on the road. By putting the pulley on the axle inside from the wheel, and the motor in a "hump" (eg) behind the axle in theluggage space, the same arrangement could even apply to a vehicle as manufactured, with the drive belt replacingthe more costly, heavier drive shafts with CV joints.

There are of course disadvantages. The belt is subject to wear, and will need occasional replacement. And this drivetrain, short as it is, should be more or less enclosed to protect it from road dirt. ...And it just doesn't seem as "cool",somehow, as a motor in line with the wheel.

Firstsketchofthenewideawheelmotormountingsystem.Themotor(presumably)ismountedonthefrontofthebarwiththepulleysbehindthebar.Thewheelpulleyboltstothewheellugnuts,andhasacenterbearingtoattachthebarto.

For a while, improvements to this layout were occurring to me almost by the hour!Eg:- Upper and lower body end bolts/pivots can give anti-twisting support, which it would doubtless need.- The motor can be mounted right over the pivot point at the back to minimize effects on suspension/handling.- Belt adjustments by motor mounting position, eg with slots for the mounting bolts. (many potential variations)- Safety cover over the belt & pulleys - to keep out dirt and gravel as well as fingers.

Suddenly the potential for DIY creation of electric car drives with small motors at home, including "hybridizing" agas car rather than "converting" it, comes back into focus as an attainable objective!

AFSRM Generator

The absence of cogging also made me think of SRM potentially as a generator. My magnet BLDC motors wouldn'tbe, eg, good wind power generators because the cogging would prevent them from starting to turn in a lighterbreeze. With no cogging, the reluctance motors should make great windplant generators. A "problem" is that withouta motor controller, they would just spin without making electricity. On the other hand, with an appropriate controllerthey could probably be coerced into putting out a constant voltage regardless of RPM. (Within attainable limits ofcourse.) That would be a tremendous advantage. Where one might have a typical "passive" generator whose outputvoltage varies linearly with RPM, followed by a very flexible DC to DC converter to output a constant voltage, insteadone could have an "active" reluctance generator putting out a constant voltage at a maximum power point regardlessof wind speed. The DC to DC converter would be replaced by the motor's controller so the controller would be analternative electronic component, not an additional one.

Electric Weel Generator

With a SR generator still being undesigned, work continued on the original plan for the big generator for the floatinghydro power unit. We got the stator coils wired together and put the magnets on the rotor. It's almost finished.

MagnetRotor.(Morelexanreinforcingpiecesaretobeaddedtothismainpiece.)

My/R & D finances?

I got my first monthly payment of 1000$ from CHIP bank - owed with interest to be collected someday from myhouse or estate. I also applied for Canada pension plan (CPP, 341$). My finances took another turn for the worsewhen I finally got my Turquoise Energy Ltd. income tax refund for 2013. For every project they didn't like theyknocked off a percentage (just in case I wasn't worth 22000$ for any one or two of them), and the government hasapparently that decided rent or equivalent for facility space to do R & D doesn't constitute a legitimate R & D expense.It looked like that would knock it down to 12000$. But I finally got my 2013 refund on March 20th 2015, nearly ayear late, and it was even worse: somehow it was beaten down to just under 8000$. I expect that pretty much coversall the time I spent doing all the paperwork I have to do to qualify for the SR & ED program - but not the actualinventive work. It certainly does little to compensate for what I've invested in the projects in time and money. Thathas been financed with a considerable mortgage on my house. I wonder how much the audit itself cost the taxpayer,complete with scientific appraisal by a university academic who seemed to sneer at the fact that I had no universitydegree and wasn't going out of my way to try to get university collaboration. The salaries of the two Canada Revenueemployees are both doubtless far higher than what I've been living and doing R & D on. Now I've started in on all thesame paperwork for 2014, all seemingly no less exacting than if I was claiming millions of dollars. And when will Ireceive some pittance for having done that? Another product developer I know, and so probably many others, havebeen similarly affected. It seems the government is cutting everything that won't cause a public uproar (andapparently even some things that do), while it involves Canada in shameful foreign wars and moves us stealthilytoward becoming a lawless police state, in step with the USA. It doesn't look like the next advances in human societywill come from the west.

The Usual Mazda Batteries Update

The electric Mazda with 11 batteries and 144 volts has become somewhat more practical again, but still only fortrips under 6 miles or so, or where I can charge a while at the far end. I've been to a friend's at 5 miles distance for a10 mile round trip a couple of times, with a 2-1/2 hour [slow, float] charge while I'm there, without getting too lowbefore getting home. OTOH, these were evening trips with light traffic and I picked a route with few stops and just acouple of steep hills (relatively short ones), and used as little as 238 watt-hours per mile (1.7AH/mile @ 140V) ratherthan the average of around 280 or more watt-hours. (Now I think I know how the EV-1 used just 225 WH/mile or so,according to various reports. It's not that the car was a whole lot better. It's that California is always warm (warmlowers consumption) and has fewer steep hills and generally longer runs between stops.) The older NiMH batteries made from "D" cells don't work as well as the newer ones - the voltages drop more whenclimbing hills or accelerating. Curiously, this doesn't seem to be a reduction in storage capacity, only in current drive,as the voltages soon come right back up fairly even with the new ones after stopping, which means the state ofcharge is the same. This suggests that the electrolyte gradually escapes. That wouldn't hurt a flooded cell (especiallyas it can usually be refilled), but the "dry" cell doesn't have much to start with. I started thinking about the possibility of refilling the dry cells, by immersing them in water for some period of time.It's an experiment I'd like to try on some older cells, but I would want to run a few load tests before and after, andideally try varying lengths of time and depths of immersion, so it'd be a fairly involved set of tests in order to come upwith general guidelines for 'restoring' NiMH dry cells, if indeed it can be done. And different size cells - and evendifferent brands - would probably have different requirements.

I'll want more "identical" batteries, eg, 3 x 300AH of NiMH.s, if I get the Chevy Sprint going with a 36 volt motor. Ithought about investing another 3000$ in "D" cells to get there. Ugh! What about my own batteries? Surely theremust be some way to make use of the new chemistries I've found instead of just paying through the nose for NiMH orlithium!

Turquoise Battery Project: Battery Production Ideas

I have two fabulous new chemistries. But I don't seem to be able to make practical batteries. I even startedthinking about the nickel-zinc oxalic acid cells again (might not care about air exposure?), and about sheet zinc as anelectrode. I thought about the way standard dry cells are made, and the fact that they work well and their carbon rodis just what would work with my salt electrolyte posodes. What about simply using the rods from "D" or "F" dry cellsand adopting the same construction? Nickel-nickel with salt electrolyte should be doable as a dry cell. (The highvoltage of nickel-manganese, fantastic chemistry attainment that it is, would make for too much gassing and pressure- they pretty much would have to be flooded, vented or valve regulated cells.) Then I figured that I could use the nickel-brass sheets as the outer layer, with the nickel in them as part of thenickel electrode. I would assume the (18%) zinc would oxidize away leaving the nickel (17%), active wherever it wasexposed to the electrolyte, and the copper (65%) as current collector. That would ensure some sort of high-currentactive nickel electrode, but with quite low amp-hour capacity.

Then I thought such an electrode might be improved by dissolving away both the zinc and some or even all of thecopper, to leave a microscopically porous nickel electrode. (17% nickel and 83% air space for electrolyte penetration.)On April 1st and 2nd I extended this great idea. I have the nickel-brass sheets, and also monel powder (Ni:Cu66:33%). If some or all of the copper was leached out of both these alloys (and all or most of the zinc) with HCl andH2O2 (or maybe ferric chloride), microscopically porous nickel should remain, with mostly nickel on the surface,exposed to the electrolyte, and any remaining copper inside as a highly conductive backing. That should make arelatively solid electrode with very high current capacity and a lot of microscopically rough, exposed nickel surfaceand hence excellent amp-hours per amount of nickel. One might be able to apply a flux [water soluble?] and sinterthe powder and the sheet together into a porous electrode with a torch, then dissolve out the zinc and [some of?] thecopper to also get the microscopic porosity. It sounds like a real winner!

Anickelbrass(AKA"nickelsilver"or"Germansilver")sheettoturnintoarolledupelectrode,withan"F"cellcarbonrodanditsoriginalplasticcap,andtheprospectivePVC3/4"

plumbingpipeasanoutercasing.(Sighthe'3/4"endcap'forthebottomwasthewrongsize.)

On April 2nd I tried an initial experiment, tossing the piece of nickel-brass into a solution of HCl + H2O2 I hadsitting in a jar for printed circuit board etching, for about an hour. I taped over one side so as to etch only the other.Sure enough, the exposed surface looked very different when it came out. It had a 'matte' appearance instead ofglossy, and a rough texture with fine ridges instead of smooth under a 40 x magnifiying glass. It looked verypromising and I'll have more info next month. (I wish again I had a microscope. Maybe I can get someone to putsome samples under the fab UVic electron microscope.) By evening I realized that that solution doubtless dissolvesnickel as well as the other metals, so I'll have to look up something else. Edison used sulfuric acid to dissolve copperfrom nickel, dissolving only a little nickel, so it's known to be doable. I think I'll try ferric chloride. It might dissolve nonickel at all.

Another interesting find was that someone has discovered that parcel packing "peanuts" can be turned into thincarbon film or carbon nanoparticles (depending on formulation) useful for battery electrodes, by heating in a kiln in aninert atmosphere, and sometimes with the right salts added. (The salts used weren't listed). A friend sent me a link tothe article. I may look for ways to try it out. The hard part will be keeping the air out, and I've wanted to be able todo that in the kiln for a number of things.

InPassing(Miscellaneoustopics,editorialcomments&opinionatedrants)

Ceres, Vesta & Vegetation

I searched youtube for any more information about the Dawn spacecraft mission to Ceres. Specifically I was hopingfor information about potential "polycyclic aromatic hydrocarbons" spectral findings or "fluffy" surface textures thatmight (or might not) support the visual appearance of Ceres as having the same strange vegetation (assuming that'swhat it is) evident on several airless worlds of the Jupiter and Saturn systems. There was a 50 minute NASA/JPL pressbriefing about Dawn entering Ceres orbit, but no one asked about those topics. There was much interest in the two"mysterious" bright spots. Since the bright spots appear to stick up above the surrounding surface, they're almost surely ice extrusions formedby expanding water, pushing up through holes or cracks and then freezing, following meteor impacts that melt the iceinto a pool that quickly forms a crust. I have yet to hear this or any plausible explanation for such features, which areubiquitous on many worlds, from the space science community. Unless that's what are being referred to as"cryovolcanoes". But they'd be very short lived as active phenomena - probably minutes to a very few hours,depending on the size and energy of the impact.

In the search for info, I ran across several quite "out there" videos: The bright spots are alien lights. Jpeg imagesblown up into pixelated squares show an alien city with square buildings. Ceres has air and water. (!) One starts to see why it's hardly possible to speak rationally of evidence for life on space forums without havingpeople instantly eject you from their membership without bothering to read what you have to say. And Ceres is, afterall, just an "oid" about 2% the size of Earth's moon. (BTW: Evidently the equatorial diameter is substantially greaterthan the polar diameter: 950Km versus 910Km, slightly different than the figure of 915Km I used last month. Sincethe gravity is so slight and the rotational period is just 9 hours, this oblateness may perhaps be accounted for bycentrifugal force. Hmm... Saturn, which rotates every 10 hours, is similarly oblate.)

Dawn had already been to the second largest (but much smaller) asteroid, Vesta, before it went to Ceres. Whatmight be so different that Ceres has a similar appearance to Jupiter/Saturn "fluffy" icy moons, while Vesta looks morelike a simple rock, like Earth's moon? Apparently, it's just enough of a temperature difference that all the water icehas sublimated off Vesta (max. 253K, -20C), while most of it has remained on Ceres (max 235K, -38C) so far.Vesta is just a little closer to the sun. But both are much warmer than Ganymede (~140K) where the apparentvegetation doubtless originated. So far the only real indication I've seen of vegetation is the low albedo and the highcontrast with the bright spots. This is perhaps a rather superficial indication, and with such a temperature difference,certainly more evidence is required one way or the other.

Hmm... I guess there's nothing stopping me from doing my own video to explain what I think is, and might be,going on!... except finding time to do it. I can see quickly wanting to make it into a half-decent production, bringing inimages and other findings from other worlds to compare and illustrate the points. It would become yet anotherproject - AWG!

I was disappointed to hear in the press briefing that Dawn's orbit is only going down to something over 100 Kmfrom the surface. (I don't remember the exact figure.) It should surely be possible to get down to 30 or even 10 Kmabove the tallest features to sample some of the finer details... like "fluffy" vegetation. Perhaps it's not time forhumanity to indisputably see and recognize alien life.

Unsustainable World Population

It has been said that in primitive 'caveman' times the world population was about 10 million. But this can hardly be

true! It was also estimated that before 1550 (before smallpox) there were about 50 million native inhabitants of NorthAmerica. This figure, for primitive hunter-gatherer societies often (if not usually) at war with each other, is quite atodds with such an extraordinarily low global estimate. If North America contains, say, around 10% of the world'sproductive land area (besides desert or arctic), we may estimate that the world population for much of our millionyear history was probably around 500 million primitive people. As herding and simple agriculture became common, the food productivity and hence the population per area ratioperhaps quadrupled. This would indicate that the world could, and probably did, support around 2 billion people inmore recent millennia. (IIRC, the population before world war one was around 1.8 billion.) When agriculture started to become mechanized, more people moved to cities and the land was gradually convertedto huge farms - "agribusiness", and an enormous population expansion began. (I remember in elementary school(~1964) my teacher mentioned to the class, and was shocked, that the population had reached 3 billion people!) It isnow well over 7 billion, and there are numerous very serious food concerns. Not only can bad crop years result inshortages, and not only is farming presently dependent on fossil fuel*, but with the gradual loss of various traceminerals from farmland soil without replacement it's been said by a USDA study to be unsustainable (which is in factobvious without a study). The rising rate of arthritis, which evidently stems mainly from boron deficiency, is just onehealth affect just now being linked to this - to boron poor soil. Besides food, various resources including land are inshort supply and the quality of life is deteriorating rapidly. This is exacerbated by the greed and hoarding of a few,and their fears of "uprisings", and war. (There are today over 50 million displaced refugees - more than at any timesince world war two.) As stock analyst Greg Mannarino puts it on youtube, "The population is in a bubble, and whenthat bubble bursts, there'll be suffering on a biblical scale. People won't have the resources to procure the basicnecessities they need to sustain their existence." (Not an exact quote.)

According to various internet sources, some who rule our world would like to see the population reduced to 500million, and they scheme means to accomplish it without bothering to inform people of their intent, educate them onthe need for population reduction, determine public opinion or explore peaceful, agreeable methods to accomplish it.Obviously 500 million is almost absurdly small - a cave days "hunter-gatherer" population and just 7% of the presentpopulation. It might put an end to human progress. Certainly much would be run down and abandoned. They needn't fret now about the growing population because in the economic collapse looming in front of us, it'sgoing to drop sharply. The most shocking estimates of "9 out of 10 Americans will soon be dead" seemdisproportionate, but "1 out of 2" would probably be optimistic and "2 out of 3" to "3 out of 4" more likely. It seemslikely to come out around 2 to 2.5 billion people remaining by perhaps mid century - about where it was when the20th century began. Again while spectacular events and disasters are inevitable, most of the deaths will probablyfinally result from plagues**. At some point of overcrowding and poverty, these become inevitable. Hopefully the survivors, with the global awakening and quickening of consciousness that is and will be taking place,and the spread of knowledge via the internet, will have the wherewithal to start a better civilization - and tovoluntarily regulate their numbers so everyone has enough for prosperity.

* To get agriculture off oil, not only is there the CNC gardening/farming machine idea (which would be powered fromthe electrical grid), but there seem to be a number of battery-electric tractor conversions out there. An electric tractormay be more practical at the present time than an electric car because it's never far from home and from its chargingstation - or perhaps from a quick battery swap.

** An interesting youtube news show that follows an amazing number of major events and "top importance" topicsincluding food and disease concerns is "The News in Two Minutes" (TheNITM") presented daily Monday to Friday by"FullSpectrumSurvival" channel. It's hard to keep up with the dizzying pace at which the news items (with relevantweb pages pictured) are presented! It's quite an antidote for TV "nothing happening here" news where usually onedoesn't get the impression that events of real import are happening daily often in rapid succession all around theglobe.

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DailyLog(timeaccounting,mainlyforCRASR&EDassessmentpurposes)

1-2nd: Finished February newsletter/report (#85)3-12: Made insulated outdoor tilapia pond12-13: Designed motor rotor to convert Electric caik motor from "unipolar" to "switched reluctance" ("SR") type.14: Made rotor. Made "torque bar" for measuring motor torque.15: Installed rotor and ran a test. (which showed stator wiring needs modification for SR operation.)16: Worked on Electric Weel development - finished stator assembly, wired stator coils together.18: inverted 3 of 6 coils in Caik SR motor. Still no apparent torque.19: Ran various magnetic experiments with two types of motor coils, the SR rotor, a steel backing bar, andsupermagnets and a supermagnet rotor. Electric Weel: started installing magnets on rotor.20: Ran a couple more SR motor experiment variations (repeated some to verify impressions).21, 22: Studied up on SR motor control "standard practices" & advancing ideas & projects.23: Glued remaining magnets to Weel rotor.24: Searched for pipe suitable for making rings around coils for AFSRM. (no luck.) E-mail conversation with a designerabout AFSRM design.25: Bought 2nd rotor for AFSRM.26: Epoxied strapping to Weel magnet rotor.27: Got sheet steel to make coil rings from.28: Battery Production ideas. (I have two better chemistries... now, how to make batteries that work and arepractical?)31: Studied another theory paper of axial flux motors for EV.s, describing a motor very similar to what I want tobuild.

Technical Papers Studied:

A Novel Approach to the Design of Axial-Flux Switched-Reluctance Motors Tim Lambert *, Mohammad Biglarbegian and Shohel Mahmud School of Engineering, University of Guelph, Guelph, ON N1G 2T6, Canada; A Design of Axial-gap Switched Reluctance Motor for In-Wheel Direct-Drive EV Tohru Shibamoto, Kenji Nakamura, Hiroki Goto and Osamu Ichinokura Elec. and Comm. Eng. Dept., TohokuUniversity

ElectricHubcapMotorSystemsElectricTransportElectricCaikSwitchedReluctanceMotor

The more I look at reluctance motors, the more I like them! The more one looks, the more their unique physicaland operational features bring tremendous application advantages to the imagination.

A Revolution for Car Hybridization?

The SR motor should prove compact and light, and if the rotor is balanced, capable of running safely at very highRPM.s. Where my BLDC magnet motors might be good for 2500-3000 RPM if the magnets are well attached to therotor (per the latest Electric Caik & Electric Weel construction), the SR motor with a simple solid steel plate rotormight be good for perhaps 8000-10000 RPM or more. If it has enough torque, and if it's geared down enough, itmight be mounted on a car wheel simply with a fixed gear (or belt) providing sufficient speed reduction/torqueincrease to reliably start the car moving rapidly or uphill. The RPM on the highway can be very high without beingdangerous or wasting a lot of power. Thus the variable torque converter could be dispensed with! That wouldrevolutionize all my plans and bring the wheel mounted car hybridizing system back into immediate focus.

Furthermore, 5000-6000 RPM for the Electric Caik size (doubtless quite attainable) is plenty high enough to get asmall motorboat up on a plane in outboard motor conversions, driving the main shaft directly and without changingthe typical manufacturer's gear reduction down by the propeller, which is so frustrating for conversions using typicalhigher torque, lower RPM BLDC motors.

Such potential benefits were completely unforeseen when I started the unipolar motor project, which has turnedinto the switched reluctance motor project!

I had been thinking the gearing down could be accomplished by a planetary gear, with the motor directly in front ofthe wheel. But near the end of the month, I thought of what seems like a very elegant solution with a drive belt, asdescribed in Month in Brief. This simple installation plan brings mounting an external add-on motor to "hybridize" avehicle back into close-up focus, as an easy DIY project.

Meanwhile Back at the Ranch...

Of course the layout of the motor, as per the usual BLDC case, is 3-phase and in fact for the Electric Caik is like theimage below except for being axial flux instead of radial. The Fleadh Electronics Ltd. web site has this to say [Myboldings]:

ThreePhaseMotorOfferssimplestsolutiontostartingandtorqueripplewithoutresortingtohighnumbersofphases.Hencehasbeenthemostpopulartopologyinits6/4form.Alternative3phasemachineswithdoubleduppolenumberscanofferabettersolutionforlowerspeedapplications.Butagainwatchoutfortorquerippleespeciallyinthevoltagecontrolsinglepulseoperatingmode.

>>

(Perhaps it's noteworthy that this company includes major electrical equipment and motor manufacturers such asBaldor in their client list.) Another document I found said (among other things):

>

SRM Drives speaks of high speed motors up to 100,000 RPM, and while that must describe quite a small diametermotor, indeed a solid chunk of steel is highly resistant to centrifugal forces. (But I still remember they guy in the1970's(?) who was promoting high speed flywheels for energy storage. His experiments and grand ideas werefeatured in Popular Mechanics and Popular Science magazines month after month (remember when there was nointernet?), until they just stopped appearing. It turned out he had been killed, and his entire lab destroyed, by the"explosion" of a huge flywheel at 50,000 RPM. Even the best steel has limits!)

The Electric Hubcap and Electric Weel would be "Alternative 3-phase machines" with more poles and lobes. (Cometo think of it, the Hubcap version with 3 coils per phase instead of 2 or 4 might not work out - instead of NS it wouldhave to be NNS or NSS. This concern was negated by later magnetic configuration ideas, below.)

In further study of the switched reluctance motor, I was surprised to see the seeming complexity of the controlcircuitry to drive it as shown on Wikipedia. (In fact, I think the first time I saw the name "reluctance motor" was inthe description of an "Asymetric Bridge Converter", and the weird circuit, with six wires to the motor coils instead ofthree, is what made me reluctant to take any interest in reluctance motors - plus the name just sounded weird.Unfortunately I didn't even look them up.) But on closer inspection, other than needing 6 power wires to the motor,it's the same six transistors and six diodes as in a 'regular' 3-phase bridge driver. But again, as noted in the SRMDrives summary above, the current is unipolar, and "glitches" transiently turning on transistors can't cause acatastrophic short ("shoot through fault") from B+ to B-. In fact, both transistors of a phase are turned on toenergize the coil - the fault condition in a regular half bridge.

This basic circuitry may be altered so that fewer components are required although thecircuit shall perform the same action. This efficient circuit is known as the (n+1) switchand diode configuration.

A capacitor, in either configuration, is used to suppress electrical and acoustic noise bylimiting fluctuations in the supply voltage.>>

The rising current shutting the coil power off is of course what I call CRM - current ramp modulation. So mycontrollers, ever since the A3938 version in 2011, already have it. (In the MC33035 based controller so far, it's in anapproximate form.) No complex DSP or processor control is required to achieve it.

Theyellowlinesarecurrenttotheactivephasecoils.Theredlinesshowinductancewithrotation,maximum

inductancebeingattainedwhentherotorpolelinesupwiththecoil.(Thecoilshouldbe'off'bythatpointofrotation.)

Left:Currentrampsupquicklyatlowspeedsandattainsdestructivevaluesunlesslimited.Theratedependsontheinductanceofthecoil,whichincreasesastherotorpolemetalgoesby.

Whenthecurrentreachesamaximumvalue,thecoilisbrieflyshutofftoallowittodropbackdown.

Right:OwingtobackEMF,currentrampsupslowlyathigherspeeds,andeitherthecurrentlimitisn'treached,orit'sreachedmoreslowlyandlessoftenandtheCRMislessactiveorinactive.

Ifthecontrolcurrentissetlowerforlessdrivetothemotor,alltheyellowlinesarereducedinamplitude.

The second "n+1 Switch and Diode" circuit seemed more intriguing at first. Where I put in a coil to dissociate thesupply voltage from the actual supply to the coil switches during voltage spikes, this circuit uses another mosfet. Thisis probably superior - more predictable and controllable. But the high-side transistor is turned on whenever any of the others is turned on. It'll get hot 3 times as fast. Itwould seem then that at least for larger motors such as mine, the asymetric bridge type is used so as to spread theload between three sets of drivers. On the other hand, my controller with the in-line coil has only three driver transistor points instead of six, with notroublesome floating high-side gate drives. If the coil can adequately isolate the supply from the battery for energypulse switching purposes, it may be the optimum solution. It was derived from not knowing what a "standard"solution might be, since I was initially trying to drive a unipolar magnet motor - a new type of motor for which I didn'texpect to find an existing type of controller. Occasionally not knowing "standard practices" in advance can be anadvantage!

A problem noted with switched reluctance motors is the generation of acoustic noise owing to flexing of the statorwith ever-changing magnetic loading. (No doubt this is to an extent true also of BLDC with magnets on the rotor, andespecially it would be of unipolar.) The polypropylene-epoxy composite bodies of my motors should damp the soundand make less noise than 'ringing' metal bodies.

ConceptDrawingtodefinerotorshape

Another consideration is electromagneticinductance into the rotor steel. Soft magneticmaterial (eg, high silicon steel) is used, and somehave used laminations or other induced currentrestricting materials. I considered using 1/4" x 2" bar stock andwelding two pieces together in an "X" (orsomething along those lines), drilling out a 1"center hole for the axle. That would give a "disk"with four good lobes, but not quite what I thoughtwould be the best shape. I finally decided that themost practical thing was to take a pre-made 7.8""disk brake rotor" disk and cut out four shapes toleave the desired four lobes in what I hoped mightbe a design with minimized torque-ripple. Mybiggest concern was that this rotor was only 3/16"thick. But at worst, the maximum torque would belower. It would also be easier to cut than thickermetal. I drew this up on the evening of the 12th,drew it on the rotor with a felt pen on the 13th,and cut it the day after that, using a jigsaw with ametal blade. It came out looking somewhat like an "ironcross" medal with the outside edges being theoriginal circular rim segments. The extra metalaround the outside edges should give the coilmore to attract when it first comes on as the lobeapproaches it, while having sufficient clearance

between the coil core and the lobe behind, plus it would spread the center of the lobe and reduce the higher torque asthe lobe approached the center of the coil. Or so went my reasoning. I thought I cut it pretty well and I didn't try tobalance it. First get it to run! Then the details.

On the 15th I installed this four-lobed rotor into the motor. I seemed very strange having no annoying magneticforces at work trying to suck the rotor toward the stator. And when it was assembled, there was no cogging - no forceexcept bearing friction. (...which was considerable. Oh well, some grease will ooze out of them as it runs.)

And I had started to consider thata very useful device would be atorque wrench or other torquemeasuring device that measured in"inch-ounces" or some such unitsinstead of "tens of foot-pounds",that I could put on the motor shaft.That could give an idea not just oftorque, but of torque ripple, bymeasuring the static torque atvarious angles of rotation. A TexasInstruments document suggestedthat torque ripple in SR motors canbe minimized by careful mechanicaldesign, which mirrored my ownthoughts. I wasn't seeing what I needed atlocal auto and tool stores. Then Ithought of making a balanced bar toput on the motor shaft, with a'pointer' on one end. This wouldpress on a small mechanical weighscale when the motor wasenergized, to give a reading ingrams or ounces. Knowing thelength of the bar, foot-pounds ornewton-meters could be derived, toa fine scale. To find the torque at different angles of rotation, the whole motor would be rotated to keep the bar level.Since the first objective would be to measure differences in torque at different angles, only a small force where themotor could be held by hand would be applied. (Maybe even just from the DC lab power supply to one pair of coils ata time, to get exactly the same current each time.) I made this also on the 15th. I found a nice bar on which it wassimple to shape a 'pointer' to press on the scale, at exactly 6.0" from the center of the shaft. Static torque per amp - including maximum and minimum if there's much ripple - can be derived by knowing thecurrent which gave the figures. (That's another reason for using the power supply, in "constant current" mode.) Tomeasure torque with the motor rotating will still need something like a dynamometer.

I foresee a problem with determination of back EMF per RPM ("Kv"): With no magnets to induce electricity into thecoils, the rotor can spin freely all it wants and essentially no voltage will be produced. Apparently if it's being pulsedby the controller this changes, but it sounds like it'll start to get complex -- couldn't any desired back EMF begenerated at any RPM?

On the 16th I hooked up the lab power supply toone set of coils and turned it on to 10 amps. Iturned the rotor to find where the torque wouldoccur and how strong it would be. (Funny I neverthought of doing this with any previous motor!) Tomy surprise there was no apparent force or torqueat any point. My best guess was that with a northelectromagnet pole at both ends of the engagedrotor lobes, the repulsion of the two northscanceled the attraction to the metal. I'd have torewire half the coils - or flip them over - to createnorth-south magnetic circuits. I manged to flip 3 coils over on the 18th. But theslotted optical interrupter drum seemed to rub onthe wires, which I had done my best to get out ofthe way. I might need to start banging on themwith a hammer to get them aside! Not my idea ofa simple adjustment. For the moment I removedthe drum. I again hooked up the power supply toone pair of coils, and again there was noperceptible force. If I put a supermagnet by thecoil, I could feel a small amount of repulsion orattraction, but not with the rotor. And not with afat chunk of steel that would stick fast to thesupermagnet. My motors with the supermagnetrotors work great with these coils. Plain steeldoesn't seem to work at all. Apparently with thereluctance motor I was moving into unexpectedlyunfamiliar territory. Of course, usually motor coils have metal behindthem, connecting them all together magnetically.

The coil cores are usually integral to the die-cut laminates that comprise the stator. Connecting metal didn't seem to

be necessary with the supermagnet motors. Going from steel backing disks to plastic composites had improvedperformance a lot. The magnets, which were connected together by the steel rotor plate, seemed to make for acomplete enough magnetic circuit. Here the steel in the rotor just doesn't seem to help. Perhaps I needed to go backto a metal coil backing plate in the stator? Since there are no supermagnets to generate current into it, it shouldn'tcause the losses that it did with the supermagnet rotor.

Configuration Experiments

The next morning (19th) I took two oldercoils with 63 turns of #14 AWG wire(instead of 21 turns of #11 - normally 3were wired in parallel instead of 3 in seriesto get to 63 turns total for Electric Hubcapmotors) and set them on a steel bar, aboutthe same distance apart as in the motor,opposite magnetic polarities up. Thesewould of course give 3 times the force withthe same current. I put the rotor over themand applied the same 10 amps. This timethe lobes pulled fairly strongly down ontothe coils. Pulling up on the rotor, it couldjust lift the heavy coils and bar. With thecoils on the bench instead of on the steelbar, the force was much weaker and itwould by no means pick up the coils, oreither one alone. I tried the same thing to repel a singlesmall supermagnet. It was stronger withthe steel backing the coils, but less notably,and the forces were stronger overall. Next I tried again with a spare ElectricHubcap magnet rotor. It was againsomewhat stronger with the plate thanwithout, but even with an inch flux gap, ithad good force either way. Finally I tried putting both coils the samemagnetic polarity and tried the reluctancerotor again. This still worked, and workedmuch better with the steel bar thanwithout, but the force was somewhatweaker than with opposite polarities.

I didn't actually measure the forces with ascale. That would have taken much longerto set up. When I speak of "somewhat"stronger or weaker I mean somewherearound double or half. "Much" weaker mightbe 1/4 to 1/8 as much force. The flux gapwith the reluctance rotor was much smallerthan for the magnet and magnet rotor, eg

1/8" to 1/4" versus 3/4" to 1".

Evidently the lack of steel backing for the coils with the supermagnet rotors simply means using a smaller flux gapto get the same force. The With the lobed steel rotor, it appears to make the difference between "works" and"doesn't work". The small flux gap might preclude having the "wall" making separate stator and rotor compartments.

As the day wore on I thought of more things to try. The toroidal iron powder coil cores worked fine in thesupermagnet motors, but their magnetic permeability is much lower than solid iron. How would iron laminate coilcores work, like the ones I was originally making with nail gun nail strips? Always wanting to keep a few "artifacts" ofearlier work (and packrat that I am), I went out to the garage and found two sets of the old original Electric Hubcapcoils. I took one in, snipped a wire so I could activate two coils alone, and put those on the steel bar. That had moresomewhat more strength than the toroidal core coils - not earth shattering but it was a notable improvement. Withthe powder cores I could just pick up the coils and bar with attraction to the rotor lobes. With the nail strip cores itwas a fairly solid pick-up that took a little shaking to break loose. I repeated the test a few days later with similarresults. Then I remembered that the 2" (O.D.) x 1" laminate type actually has more iron. The 2" x 1" toroid cores withthe 1.25" hole in the center have only 60% as much. Doubtless that explains the strength difference, rather than anyqualitative difference between materials.

I put the shaft through the rotor so it sat just above the coils on the end of the shaft. With either set, the rotorwould turn until two lobes were in line with the coils. That didn't necessarily mean there'd be a lot of torque, but amotor made this way would definitely run.

But I thought of yet another trick. I had purchased a couple ofyears ago some ceramic "cup magnets" that I saw on line whenordering supermagnets. Although ceramic magnets aren't verystrong, these boasted an impressive pulling force. The magneticmetal "cup" surrounding the magnet concentrates the flux into anarrow gap between the magnet and the rim, and just in front ofthat gap is its powerful pull. Why couldn't this technique be usedwith an electromagnet to greatly increase its strength in anarrow flux gap between coil and rotor lobe? The cup magnet technique should also make the steel backingredundant, since it completes the magnetic circuit locally at eachcoil. Plus, since that's the case, it wouldn't matter which polaritythe coils of each phase were: the three coils per phase in the"Electric Hubcap" motor size should be fine. But testing the "cup electromagnet" idea out was going to takemore than a quick setup: parts would have to be made. (andfrom what?) And cups, if used, would have to fit in the crampedCaik motor stator area.

I found a pipe (chain link fence type) that seemed to be aboutthe right size for the outer rim of the 'cups'. It barely fit over thecoil wires - and might need a few protruding "next layer" turnsremoved. But it was rather thick walled. Not only might it be hard to fit, it was going to take some cutting to geteven-length 1" cup sections. (at least, if I cut them with an angle grinder.) I decided to wait until Monday and see ifthere was an electrical conduit pipe size that was better. (And if it could be cut - evenly - with a pipe cutter, so muchthe better!) Those were about the only types of pipe I could think of that just might be suitable. The place I went tothen (24th) didn't have any large enough.

While all the rest was in progress, I had been on the motorcontroller e-mail list. A couple of people, one in particular,were very interested in the SR motor concept. When Iexplained I was doing axial flux, he replied on the 24th andsuggested having two rotors, one on each side of the coils.This idea grew on me. I had thought this impractical andseemingly unnecessary for magnet motors, but here,struggling to find more flux and magnetic force - torque - itseemed like a good idea. Later I continued reading the axialflux SRM paper and found "everyone" is using two rotors.

I could still put a pipe/ring around the coil (or bend 1" widesheet steel into circles), but instead of being like the cupmagnet, both ends would have open gaps and wouldinterface with a steel rotor. It would even out axial forces,too, so there'd be no pull towards one end of the motor atany time, quite unlike the continuous pull of magnet rotorstoward the stator side. There should be, if perhaps notdouble, at least substantially more torque than with a singlerotor.

Here I realized I'd hit a point of almost complete redesignof the motors. They'd have to be re-done more or less fromscratch. My experience in designing and building molds andmotors should shorten the process substantially... but withsomething new, you never know for sure. Somehow the coilswill have to be held in the center, inside metal rings, withvery thin flux gaps to adjacent rotors on each side, too smallto permit separator walls. God only knows how thick theouter perimeter would have to be to protect against a steel

rotor flying apart at very high RPM. On the other hand, the chance of that happening is pretty remote, and the massof the rotor is relatively small. Perhaps the biggest bonus for SR is that the solid steel rotor is safe up to very highRPM.s. The optical position sensor unit could perhaps use the petals/lobes of one of the rotors itself as the opticalinterrupters. It might have to be installed last, inserted through the outside perimeter wall. In fact, it might best bedone as three separate inserted sensors. Or there could be a slotted drum with the electronics mounted in one end"bell". How "fat" will the pancake be? (Stator coils 1.0") + (2 rotors 1/4" = .5") + (two flux gaps of 1/16" = .125") +(clearance, rotors to end walls [with bearings] .375" = .75") + (two end walls 3/8" = .75") = 3.125". If the actualbuild pans out, that's over 3/4" thinner than the single magnet rotor type. (Not counting the protrusion of needle or"trailer wheel" bearing hubs. A single rotor unit would work out to just 2.675" thick!)

On the 25th I bought the second rotor. These are (I believe) cast metal, with a built-in 1" machined and keyedcenter hub. The next day I wrote to the chief author of the AFSRM paper hoping for comments on my design. Then Itried to magnetize a cut-off piece of the first rotor by rubbing it with a supermagnet. It wouldn't hold magnetism! Thesoft magnetic rotor material is the best, and I had it. A rotor that holds magnetism would cause losses. It would be

good for functional "gosh it runs" motor tests, but not for a finished motor. I guess you wouldn't want a disk brakethat picks up metal particles, which would scratch it and wear it out, and it was made soft magnetic to prevent that.Evidently I lucked out. Next I decided that the only way to get an outer ring just the right diameter would be to roll it from flat stock. Onthe 27th I went to a sheet metal fabrication shop and got a piece of sheet steel, about 8" x 48" x .032" (20 gauge) ...from their scrap bin. That was a little thinner than I thought best (.04-.05?) but beggars can't be choosers. Would twowinds of it around the coil work, or would that just diffuse the magnetism? I decided one layer would be best. Iwanted soft magnetic material, but thought it might be hard to find, and I forgot to bring a magnet to test with.Anyway, I wanted to get the motor running before worrying too much about efficiency. To my surprise, the sheetwouldn't magnetize. Had I just 'lucked out' again? Or was it made that way (a) because it was cheaper, or (b)deliberately, because you don't want your furnace ducts picking up shards and filings of steel either? At this point I tried several bits of steel, including a mild steel bar, and found most of them wouldn't magnetize. Athreaded rod and a drill bit did and they would then pick up steel washers, so I wasn't doing something wrong.Apparently "soft magnetic" steel is much more common than I thought, and the annoying magnetization and pickupof filings and bits of steel by drill bits, files and screwdrivers isn't "the norm" with most steel stock types.

The design of the coils, it seemed, needed only a little change. The biggest constraint was that nothing could stickout either end, even a little bit, since there would be rotors flying by in very close proximity. (.5 to 1mm?) The secondone was that each layer of wire would make the gap between the inner toroid and the outer ring wider. Where I hadbeen using 21 turns of fat #11 wire per 12 volts, turn #21 started a third layer since just 10 turns fit on each layer.Then, in order that the inner end of the wire could come out without protruding past an end, the second layer couldn'toverlap the first wire. At first I thought that meant eliminating turn #20 as well as #21, leaving just 19 turns - a 10%reduction. Then I realized turn #20 could end just before the protruding inner wire, putting the inner and outer wireright next to each other - a lesser 5% drop. Okay! But if the outsides of the coils were to hang over, past the outeredge of the coils, then the protruding wire would be okay. At first glance, that would seem to be just lost flux. OTOH,it's mainly the leading edge of the coil where the flux is most needed. The loss is in the middle of the outside edge.

I took a coil, which had the old cotton insulation, and unwrapped two turns to get it down to two layers of wire.(They unwind disturbingly easily considering they're epoxied on.) Then I cut a piece of the sheet metal ~1.05" x 9.5"with tinsnips. I wrapped it around and found it only needed 8" length. The O.D. was just ~2.55", or less than .3"radius of wire and outer ring around the 2.0" core. With modern insulated magnet wire, it would be slightly thinner,with slightly less than 8" of 1" strip sheet metal required. If the core to ring gap was just, say, .25", but considering the core itself had .375" thick walls, I estimate the bestflux for the rotor occurs within, say, .25" to .35" of the coil. With a gap of (

But testing of the motor on the 19th showed there would be a bit more to the motor configuration/construction thanseemed to meet the eye. And there was the little tested motor controller with the hot transistors. The time to get aproperly working unit might stretch out unduly, while the rest of the floating hydro power unit was ready to go. Thedeveloper came over that afternoon and we started installing the magnets onto the rotor per the original plan.

Other Switched Reluctance Motors For EV.s

Early in the month someone gave a link to a press release for a larger switched reluctance motor, underdevelopment. They think SR is "the next generation" of EV motors, and I agree. Why they aren't the presentgeneration is beyond me. Apparently most others have been no faster off the mark than me in this regard. Of course,in general all the advantages and features Ricardo is touting for their SR motor apply equally well to any I mightmake. And I think the axial flux will be better -- certainly it'll make motors ideally shaped for wheel mounting. Aninteresting feature of their motor is the "distributed stator winding". That can't be done with individual coils, and alsowould likely require more elaborate control electronics than I presently intend to make.

Later in the month I found more technical papers specifically on axial flux switched reluctance motors (AFSRM.s)that have been helpful in modifying if not redefining what I want to build.

http://www.ricardo.com/enGB/NewsMedia/Pressreleases/Newsreleases1/2015/Ricardodevelopsnextgenerationelectricvehiclemotor/

Newprototype85kWsynchronousreluctancedrivedesignedprimarilyforelectricvehicletractionapplicationsAvoidstheuseofexpensiverareearthelements,providesuncompromisedperformanceatsignificantlyreducedcost

Thenewelectricvehicle(EV)motorhasbeendesignedandbuiltinprototypeformbyRicardoaspartofacollaborativeresearchanddevelopmentproject,RapidSR(RapidDesignandDevelopmentofaSwitchedReluctanceTractionMotor).Usingaconventionaldistributedstatorwinding,theRicardosynchronousreluctanceelectricmachineisahighlyinnovativedesignthatmakesuseoflowcostmaterials,simplemanufacturingprocessesanduncomplicatedconstruction.Ithasarotormadefromcutsteellaminations,whichareusedtodirectandfocusthefluxacrosstheairgap.Bymaximisingthisfluxlinkagebetweenthestatorandrotor,performancecanbeoptimizedwithinatightlypackaged,lowweightandrareearthelementfreedesign.

Asthemarketforelectricvehiclesgrowsglobally,thereisanimperativetoexplorealternativestopermanentmagnettractionmotorswhichrequiretheuseofexpensiveandincreasinglydifficulttosourcerareearthelements,commentedPaulRivera,MDoftheRicardohybridandelectricvehiclesystemsbusiness.TheRicardoprototypethatwehaveannouncedtodaydemonstrateswhatcanbeachievedbyusingthelatestelectricmachinedesignprocessesinthecreationofahighperforming,compact,lightweight,andrareearthelementfreeconcept.

Sinceitslaunchin2012,theRapidSRprojecthasbeenresearchingthedesignofnextgenerationeconomicelectricmotorsthatavoidexpensiveandpotentiallydifficulttosourcerareearthelementstypicallyusedinpermanentmagnets.BydevelopingeffectiveCAEleddesignprocessesaswellasprototypedesigns,theteamhascreatedaframeworkforthefuturedesignandmanufactureofelectricvehiclemotorsthatoffertheperformance,compactpackagingandlightweightrequiredforEVapplications,butatasignificantlyreducedcostcomparedtopermanentmagnetmachines.RicardospartnersinthisresearchincludeprojectleaderCobhamTechnicalServiceswhichisdevelopingitsmultiphysicsCAEdesignsoftware,Opera,asapartoftheprojectandJaguarLandRover.TheresearchisbeingcofundedbytheUKsinnovationagency,InnovateUK.

BybringingtogetherstateoftheartsimulationtechnologywithadvancedelectricmachinedesignwehavecreatedahighlycrediblenextgenerationEVmotorconceptthatshowsconsiderablepromise,addedDrWillDrury,Ricardoteamleaderforelectricmachinesandpowerelectronics.The

Ricardoprototypeisnowbuiltandwillberigorouslytestedoverthecomingweeksinordertovalidatetheextremelypositiveresultsthatithasshowninsimulation,asaconceptthatprovidesanexceptionalbalanceofperformance,compactpackage,lightweightandlowcost.

Mid-month I found a paper discussing designing of a two-rotor axial flux reluctance motor for car wheels:AF-SRMs-03-00027.pdf from a team at the University of Guelph in Ontario.

(Heading/Title:)>>

A Novel Approach to the Design of Axial-Flux Switched-Reluctance Motors Tim Lambert *, Mohammad Biglarbegian and Shohel Mahmud

School of Engineering, University of Guelph, Guelph, ON N1G 2T6, Canada; Published: 3 March 2015

It was 28 pages and it took a while to read it, even without trying to 'get into' most of the electromagneticequations. I think it was just theoretical and nothing had actually been built - there were no photos. Their ideasseemed to parallel mine except they were trying to make a larger motor that would turn the car wheel directlywithout gearing down. It seemed rather heavy at 41 pounds. Addresses were given and I e-mailed the chief authorfor possible comment about my own design. One important feature I noted was that instead of being typical 3-phase it had 8 coils and 6 lobes on the rotor. The8 coils were to be driven by 8 half bridges. Since 8-6 is symetrical at 180, four half bridges could each drive 2 coils,making it 4-phase. I assume this arrangement must give more torque. In the 3-phase version, generally only onephase is powered at a time. For the 4-phase to have more torque, two phases out of four will have to be energized atleast part of the time, or the current in the active coil will have to be higher per copper area, in order to achieve that.That implies more complex control than my simple plans. In fact, it will probably mandate using a microcontroller inplace of the simple motor controller chip. But maybe that's not a bad thing since it can accomplish other controlfunctions like regenerative braking without adding more control components later.

EnergyConversionEfficiency(ECE)ofAxialFluxSRMComparedtoOtherSRM.s,showingthedesirabilityofusingaxialfluxforSRmotors.

(NotethatECEdoesn'tmeanoverallefficiency,whichwillbequitehigh.Mostoftheenergyinacoilisreturnedtothesupplywhenthecoilisswitchedoff.)

This paper had a reference to another axial flux SR motor design paper, which I looked up on the 31st: yazaki_5_1_ronbun.pdf . This paper is only 6 pages, but it was packed with good info, and it wasn't just theory. Theyactually built and tested a test model.

(Heading/Title)>>

ADesignofAxialgapSwitchedReluctanceMotorforInWheelDirectDriveEV

TohruShibamoto,KenjiNakamura,HirokiGotoandOsamuIchinokuraElec.andComm.Eng.Dept.,TohokuUniversity

The Japanese paper described two motors. The second one is the 3-phase AFSR motor of 12" diameter of which a model was actually builtand tested. It was the most interesting to me because it's near my sizeand parameters. It has twice as many coils as I usually use, 18, withthe sort of "co-linear" shape of leading and trailing edges that I hadidentified as probably having the most flux and hence the most torqueper coil and per amp for this type of motor. The 12 narrow rotor polesare substantially different from my "lobes", partly in keeping with thenarrow coil cores. An interesting feature is the "Stator support link", which apparentlysplits the coils in half, or at least the copper windings (it's not reallyclear), but which must provide a means of fastening the stator in thecenter of the motor, between the two rotors. The text mentions itbeing related to the two rotors shrinking the tiny gap owing tomagnetic attractive force to the stator. (Once again this model had noexternal shell - the rotors were the outside and the stator connected tothe stationary axle.)

Theoretically it would deliver up to 302N-m of torque, which is justover 200 foot-pounds and should be adequate to run the Chevy Sprintwith no gear or belt reduction! The motor said the motor had a speed of "up to 330RPM", allowing avehicle to achieve a speed of 30 Km/hr. This seems like an absurdlylow top speed for a motor with solid steel rotors. A test graph showedup to 800 RPM, and with loss of torque with speed at very low speeds.Of course, this depends also on the applied voltage and the back EMFof the design, so it may be that the applied voltage could easily behigher (or the number of turns in the coils reduced to lower the backEMF), resulting in higher available speeds.

Since I already have the Chevy Sprint configured with a transmissionunder the hood to which the motor could be attached, a 2 or 3 to 1speed reduction could be obtained with a chain or belt drive (to theoriginal differential), giving more torque, with a higher speed - up toabout 2300 or 3500 RPM at 100Km/hr on the highway. Even if thetorque of the motor and controller I build don't attain those in thepaper, it would still have plenty of force.

I can see how all the little short segment, intense flux transitionscould deliver much more torque than the wide lobes of my presentdesign - over very narrow areas with rapid coil switchings per RPM. Maybe I'll concentrate on getting the first motor done and working,and the controller working, and all installed on the outboard using the

present design, while I consider all these probably desirable designs for larger car motors. I do have one or tworeservations. Foremost, their design seems to have a lot of torque ripple. Second, the low RPM.s indicated, includingrapid torque reduction with RPM, must be the result of the rapid flux transitions from the narrow coils and rotor poles.The high torque may come with the high torque ripple 'built in', and it may limit the available RPM, with high backEMF at low speeds. I may still find the 9 coil, 6 rotor poles version has more desirable characteristics. ...or maybe 12coils and 8 rotor poles? ...or?... And maybe some rotor pole edge shaping to reduce torque ripple, even at theexpense of maximum torque. Doesn't the motor have to start the car rolling even from its minimum torque positions?Better to raise those. Or, I might change the pie slice coil shapes to something more like diamonds or rectangles,which would be the same as edge shaping and also would allow some air flow gaps across the coil windings forcooling. (And rectangular pieces of steel would be easiest to cut - assuming I can use solid soft magnetic steel insteadof laminates.)

ElectricWeelMotor(Generator)

Rick Linden of Pacific Coastal Geoscience, the designer and builder of a floating river hydro power generator, cameover on several occasions and we worked on finishing the Weel generator for the unit.

First we finished wiring up the stator coils. We wired it as two sets of 4 coils in series per phase, which left 12 wiresto hook up, and it can be configured as 8 coils in series (higher voltage) or two sets of 4 in series (higher current).The actual voltages and currents will depend on RPM, and on the adjustment of the flux gap.

We epoxied the 32 magnets to the rotor'souter steel ring, 16 at a time in two separatesessions. Since the rotor unit was too big toput in the oven, a day or more had to beallowed after each operation for the epoxy toset. Before the second session I made a jig toallow safely inserting the second set magnets(north up) between the magnets of the firstset (south up). Once in place, each magnetwas clamped down to ensure it wouldn't snapover against one of its previously installedneighbors.

In a third session, we put the main lexan ring in and wrapped the polypropylene strapping around the magnets andthrough the slots in the rotor. This should ensure they're well attached and able to take considerable centrifugal force.A 26" diameter magnet rotor is an impressive looking rotor!

EpoxyingonthePPstrappingtosecurethemagnetsandthelexanrotor.

Aligningthelexancenterheightwiththesteelringusingspacers,andweighingdownthestrappingtokeepitinplacewhiletheepoxysets.

Themagnetsideisdowntokeepthestrapsevenagainsttheplywoodwithnoprotrusions.

The'magnetized'rotor.Lexanrotorreinforcingpiecesaretobeinstalledaftertheshaftiskeyedtoensurealignment.

The pull from the magnets to the stator will of course be immense, probably getting up into the "hazardous" rangefor fingers even with the safety wall between the rotor and stator ensuring a considerable flux gap. (I look forward togetting all the details figured out for producing switched reluctance machines, which won't have any permanentmagnets to mount or to fight with.)

At month's end the main things left were to machine the dual key slot into the main shaft, and then to place thelexan reinforcement pieces on the rotor and glue them with methylene chloride. The shaft was to have been keyedelsewhere, but the machinist was too busy so it didn't get done. Neither did I get to it. Thus it sits, nearly finished.(We got it done on April 3rd.)

"Green"ElectricEquipmentProjects

Aquaponics&LEDGrowLightingProject

LED Grow Lights

Early in the month one emitter in the white light made with the LED emitters from dx.com started flickering. Acouple of days later it went out, and another in the same row started to flicker. The next day it didn't work at all. Thisis a theoretical weak point of my lights, that if one emitter of four or five in parallel quits, the same current is pushedthrough the remaining emitters and so they work harder. Still, the currents were under 1/2 the specified maximum,so the four remaining emitters should have had no problem. I already noted that the dx.com emitters had highervoltage drop and also weren't as bright as other seemingly identical emitters I ordered from a Chinese store onaliexpress.com. And the 10W dx.com LED "light bulbs" probably made with the same emitters keep burning out andneeding an emitter replaced. While they run warmer than ideally in both lights, I finally conclude they are just crappyemitters, to be avoided.

On the 17th I tried swapping thetwo LED grow lights, with differentwavelength blue (450nm) and violet(420nm) emitters. I keep saying howmy linear current current regulatorsare really efficient at 12 volts. But theviolet one was now getting 13.65volts from the solar system instead of12.0 volts from a power adapter, andsoon the transistor heatsink bar wasquite hot. I measured the voltageacross the lights and it was just 9.75volts - apparently the violet emittershad somewhat less forward voltagedrop (3.02v) than the blue ones(3.23v). At 12 volts the supplyefficiency would thus be just 81%. Atalmost 14 volts the power transistorhad about 4 volts across it and wasthus dissipating 6 watts extra in a 15watt light, total 21 watts. That's only70% efficiency. That's probablytolerable since 14 volts means thesolar panels are working... but it runstoo hot! Evidently I could either haveput an extra row of red LED.s in it for11.65 volts, or used 3 rows of violetemitters and just one of reds(10.85v).

But I'm starting to think that thereal solution, for best power supplyand LED emitter voltages flexibility, is,after all, to use a switching regulator.It might probably be only about 85%efficient where I - ideally - get up to90% with the linear, but the "ideally"is hard to get. The switching regulatorwould be good at all supply voltagesand with any combination of emittersI might put in a light. And it wouldmake 1/2 the heat of 70% efficient.

Tilapia Pool

On the 3rd I finally decided that the tilapia pond would be atrench in the garden, made with the rubber(?) pond liner.Weeds from the garden could be pulled and thrown in, wherethe tilapia would hopefully eat them, reducing the fish food bill.And it was close enough to the greenhouse to pump water toand from to flow through greenhouse plant beds. And moresecure - easiest to fence off from raccoons. I couldn't figure outwhere to put without blocking a path until I thought of simplyputting a bridge across the trench. Tilapia like cover anyway. Idug out the outline of the trench, not to full depth, and lookedagain the next morning to see if I actually wanted it there.Wherever it was in the garden, it'd be somewhat in the way.

Thetrench~18x22x76".PeoplewerewonderingwhoIwasgoingtobury.Idon'tthinkI'veeverdugthegardendowntothesubsoilbefore!

With it being outside, I decided that the bottomand sides should be insulated so it could be heatedto extend the season, or perhaps, with aninsulated top cover, even be used all year.Fiberglass was out, and the cost for styrene foamwould add up. But not as much as electricity costto heat an uninsulated pond!

It took about 3 days to dig out the pond. Then Ifilled it from drums of rain water, to about 95imperial gallons, 115 US gallons or 430 liters. Thisleft a lip of about 6" to keep fish from jumping out.Then somehow it took another few days to put aconcrete surround around it. The store ran out ofconcrete paving blocks, and I ended up makingsome as well as buying some.

I saw small insects flying near the water andalighting on it. I thought about breedingmosquitos. The water was too cold for tilapia,barely 10 degrees C. I could either get a heater,allow mosquitos to breed... or get some goldfish. Igot 11 small ones, "feeders" according to the petshop. Then I got some more duckweed from mybrother's ponds. The goldfish won't eat it. It growsrapidly and I can feed the surplus to the tilapiawithout having them make it extinct. By the end ofthe month, the water was up to about 14.Theoretically tilpia wouldn't die, but it surelywouldn't be good for them. Trout come to mind...So does hooking up the whole aquaponics systemin the greenhouse, including a small solar waterheater Jim Harrington gave me to help warm thewater in the pond and system. I'm not really clear just where I'm going here.Having dug the pond, I worry about raccoonscatching the fish if they're in it. But the largesttilapia is almost 12" long, in a 12x12x12"aquarium space, and will have to be movedsomewhere soon. (There's always a 200 literplastic drum with the top cut off, I suppose.) Theone little tilapia is now about 2-1/2".

I decided to use the big swimming pool as a reservoir for watering the garden in the summer, city water havingbecome rather costly. Someone said he had one and a seam split and all the water was lost. So I don't want to investtoo much in it that would be lost if that happened, ie, valuable fish. I channeled water from my house roof downspoutand from my neighbor's garage roof. (It spills out of his gutters and turns that end of my yard into a swamp. I put anopen top "barrel" with a hose tap at the bottom just across the fence to catch it.) Just after it was set up to fill therewas a great 36 hour deluge, and it was 11" deep. With further March rains it got to 20" - probably 1500 imperialgallons. I suppose when I see inevitable mosquito wrigglers I'll throw in some goldfish. Come to think of it, I couldsurely put in some duckweed! (I did.)

Beans!?

I was about ready to rip out the bean plantsfrom the aquaponics grow bed. They had grown aswell as any pole beans in the garden - better - butwith no flowers it all seemed pretty useless. I hadadded a bit of potassium chloride for potassiumand trisodium phosphate for phosphorus, butnothing was changing. On the morning of the 16ththere was one orange flower high up. This wouldhave been most welcome 2 months ago! Now itmerely dampened my resolve to be done withthem and try other plants, that I had finally arrivedat. The flower shriveled in a couple of days, and nonew ones appeared. One thing the beans did appear to have donequite well was their job of removing fish waste -ammonia that gets converted to nitrates bybacterial action - and converting it to plant growth.The water in the system stayed quite clear withlittle algae growth. (On the other hand, the tilapiaseem to eat at least some types of algae.) Other than that, they're a bit of an oddornamental house plant!

CordlessLawnmowerwithNiMH"D"cellbatteries

Quite a while back Jim Lawrence, the friend who helped me with my web site, had bought a cordless lawnmower.These silly things use lead-acid batteries, which of course don't last long. After he had bought replacement batteriesthat only seemed to last a year for not much less money than the original price of the mower, I volunteered toreplace them with 40 NiMH "D" cells. (24V, 20AH.) The only part a bit tricky was the charging. On the charger cord Iput in a diode and a resistor to drop the voltage a little from what the PbPb types took for charging. Later as I learned how the fat copper straps I was using would work loose with vibration, and how such 'batterypacks' could be dangerous with only the low-temperature plastic insulating the cells from each other, I "recalled" themower and re-soldered it all with #16 stranded wire and tarpaper sheaths around the cells. Since then, the onlyproblem has been that a wire in the charger assembly came loose once. Now Jim has sent me a review on the mower with the NiMh battery. (Yes, we were already mowing lawns here inVictoria BC in February. We had no snow this winter - only a few frosts.)

Hi Craig:

Find attached a couple of photos of my electric lawnmower powered with your metal-hydride batteries.

The pros are as follows:1. Mower is super light in weight and easy to push around.2. Batteries have been running around five years and seem asgood as new.3. Needs no oil or gas.4. No fumes or bad smells.5. Quiet as a vacuum cleaner.6. When turned over for cleaning, no fuels or oils drains out.7. Always starts instantly.8. Easily does my lawn and even the next door neighbourslawn on a single charge.9. Requires virtually no maintenance.10. Unlike regular batteries, they are not toxic.11. Inexpensive to power.

The cons are as follows:1. The cutting blade still needs regular sharpening.2. Needs a steady trickle charge to keep the batteries full.

Pro or Con?1. Initial costs of batteries are high but after a few years costsaverage out much better than any alternatives.

Hope this helps for your next review. Maybe you should startselling an upgrade kit...$500 for potentially 10 to 15 years ofuse...good investment.

Jim

ElectricityStorageTurquoiseBatteryMakingProject

CylindricalBatteries?

Seeing I couldn't seem to stop the flat plate cell leaks, apparently through the graphite foil, and that this waspreventing me from making batteries, I thought again of the carbon rods used in standard dry cells. I started towonder how it would work out if I made batteries with "F" or "D" cell carbon rods, with similar construction to simplestandard dry cells? Ideas started forming. I didn't see how I could reliably jam things together under pressure without breaking thecarbon rod and ripping the separator sheets before it was together. But there's the fact that the nickel oxides in the positive side always expand. Perhaps if I made use of that I couldmake things so they'd start with just enough play to set the layers in place to put together the cell, and when waterwas added, it would swell and everything would be a tight fit. This seems to be worth a try, given that nothing elseseems to have worked, and since it seems to work somehow for billions of dry cells. Whether it would be a "dry cell"(AKA starved or limited electrolyte cell) or wet/flooded seems to be of little concern at the moment.

So the "layers" of the cell would start with the carbon rod in the middle. Surrounding that would be the fat posode cylinder of nickel manganate with carbon black. I'm not sure how thegraphite felt could be worked in since it would be compacted from one end, but perhaps I could cut some strips or bitsof it to throw in. This electrode would be compacted inside a pipe, closed at the bottom and with a metal rod just atrace fatter than the carbon rod. A die would push into the pipe, filling the space between the center rod and the pipe.All these would be much longer than the intended electrode in order that the powder could be poured in and thencompacted in one press. Around that would be the separator, probably paper plus a couple of layers of PP non-woven fabric, then morepaper. But I'd try different things to see how many layers were really necessary. Surrounding that would be the negode of nickel and monel, and perhaps more carbon black. This would be done thesame way as the posode but of course with larger diameters so it would fit around the inner parts, just looselyenough to slip over the paper without trouble. Finally would be a metal pipe, tube or can to hold it all and form the negative terminal. (This got changed to a PVCpipe with end cap, with a sealed bolt for a terminal.) A plastic disk piece would fit the top and if necessary the bottom. Perhaps the tube could be crimped on the endsover this/these pieces. (Perhaps I could save the crimped metal terminal on the carbon rod from the original cell.)

Before crimping the top on (or before screwing in the bolt?), electrolyte would be added. This should cause the

posode to swell and take up the slack spaces, tightening around the carbon rod and pressing against the separatorlayers.

Some thoughts... A Nickel-Zinc or Nickel-Nickel Acid Battery?

As I thought of configurations with a carbon rod electrode in the center, I kept thinking of the rolled-up dry cell.Nickel-nickel would be the obvious choice. The high voltage of nickel-manganese with its bubbling during chargingwould probably preclude such a tightly wrapped up configuration. What would the current conductor layers be? Thegraphite foil would crack if rolled, so that leaves the graphite foam and flexible sheet graphite gasket material.

For the negative, the zinc sheet came to mind. But the reaction voltage of zinc would have it oxidize before thenickel... it would then be a nickel-zinc battery. Iron might be good; maybe stainless steel mesh. Or perhaps thecopper mesh. There'd be nothing to stop the negative terminal from being metal - only the plus side has to be carbon.Pieces for the negative could be tack welded together and to the mesh. The carbon rod and a sealed metal rod forterminals would allow for very minimal leakage of electrolyte. It could work.

But what about that zinc? A sheet of zinc works quite well as an electrode. The trouble with zinc is thatintermediate-state soluble zincate ion that causes it to form dendrites, branching "roots" of zinc during charge anddischarge. This both corrodes away electrode substance and tends to short out the cell.

This brought me back to a theoretical idea I had quite a while back, and I made a demo cell just to show it could bedone. The reason lead is used for lead acid batteries, despite its high atomic weight and consequent low energy perkilogram, is that lighter metals would dissolve in the acid. I looked for an acid that wouldn't dissolve zinc and nickelcompounds. And I found one: oxalic acid. Neither nickel, nickel oxalate, zinc nor zinc oxalate was soluble according toa table. (The state of charged nickel, oxide, and its potential solubility might be a bit of a wild card, as well as theexact reaction voltages - AFAIK this is pretty uncharted territory.) Back then, I made a little test cell with a piece of nickel hydroxide electrode from a Ni-Cd dry cell and a zinc rod toillustrate the point. It worked but had little current and seemed to deteriorate. The voltage dropped and chargingdidn't entirely restore it. But it was open to the air in a beaker and the posode current collector was made for pH 14,not pH 1, and would obviously deteriorate. It was hardly a definitive test except for showing an initial voltage of[IIRC] about 1.7 volts.

The likeliest nickel reaction (I think) would be something like: Ni(COO)2 + 2e- Ni2(COO)2 + (COO)22 .

Now the likely zinc reaction is: Zn + (COO)22 Zn(COO)2 + 2e- . The environment is acidic and the compoundisn't ZnO or Zn(OH)2 . Will the zinc still form the intermediate soluble zincate ion, or will the reaction go direct asindicated above? The zincate ion is more usually associated with an alkaline environment. There have been a lot ofpeople who've tried a lot of different things to p