FRM 5101460 AFCC Research Needs Analysis for Generation 4 Vehicles.

FRM5101460

AFCC Research Needs Analysisfor Generation 4 Vehicles

2 FRM5101460

Future GenerationsFuture Generations

Generation 1Technology Demonstration

F-Cell

Generation 2Customer Acceptance

B-Class F-Cell

Generation 3Cost Reduction I

Generation 4Market Introduction

Cost Reduction II

Passenger CarsLead application



Bus



Sprinter

Generation 5High Volume

Series Production

2004

2010

2013

201x

202y

Fuel Cell Roadmap - The Path to Commercialization

Fuel cell passenger cars will drive the volume

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Status of Fuel Cell Technology

PerformanceSafetyComfortFreeze startRange

ReliabilityLongevityPackage/weightCost

Generation 3 Cars will demonstrate competitive capabilities.

Cost remains the challenge!

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5 Basic Strategies For Cost Reduction

Detailed examination of all 5 areas will indicate the best paths for further improvement.

Investment of development dollars

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Mining For Cost Reduction

Given multiple options a good miner:• Drills new test holes.• Explores a few high risk/high gain paths.• Exploits the known paths fully in order of their value.• Saves some lower value ore bodies for later exploration.• Knows when a ore body is exhausted.

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Distillation

Technology Area

Driver Size Dura Fuel Econ

Cost Criticality Understanding

Opportunity

Classification

0.1 0.2 0.3 0.4

Catalyst Catalyst Coating Technology 1 3 3 2.3 Med Med Engineering Catalyst Catalyst Primary Process 3 1.2 Low High ResearchCatalyst Catalyst Recycling Process 1 0.4 Low High ResearchCatalyst Freeze tolerant Catalyst Structure 3 1 1 Med Med Research

Catalyst Carbon supported Pt 9 9 9 9 9 High Low Technoloy at Limit

Catalyst New High Activity Catalyst 9 9 9 9 9 Low High High Priority ResearchCatalyst Less Platinum 1 9 9 9 8.2 High Med High Priority ResearchCatalyst Non Carbon Catalyst Support Materials 9 3 3 3.9 Low High High Priority ResearchCatalyst Pt Dissolution Resistant Catalyst 9 3 9 6.3 Med Med High Priority ResearchCell Design Better Mechanical Integration 9 0 3 2.1 Med Med EngineeringCell Design Higher Stack Peak T 3 3 9 4.5 High Med EngineeringCell Design Low Force Seals 9 3 1.5 High Low Technoloy at LimitCell Design Low Pressure Drop Anode FFs 3 3 3 3 3 High Med EngineeringCell Design Minimize Port Areas 3 3 1.5 High Low Technoloy at LimitCell Design Minimize transition areas 3 3 1.5 High Low Technoloy at Limit

Cell Design Near Dead Ended Cells 3 3 3 3 3 Med Med ResearchCell Design Robustness of design to MFG tols 1 3 3 1 2 High Low Technoloy at LimitCell Design Self Hydrating Cell 3 9 3 3 4.2 High Low Technoloy at LimitCell Design Smaller Seal Foot Print 1 3 1.3 High Low EngineeringFCS Ability to Boost Voltage from Stack 3 9 3.9 High High EngineeringFCS Efficient Air Compressor Technology 3 3 9 9 7.2 High Med High Priority ResearchFCS Higher Temperature Humidifiers 3 1.2 Low High ResearchFCS Less Expensive Humidifiers 3 9 9 3 6 Med High High Priority ResearchFCS Less Expensive H2 pump 3 3 3 2.7 Med Med EngineeringFCS Less Expensive Intercooler 1 0.4 High Low Technoloy at LimitFCS ( vehicle) Less Gross Power 3 9 9 6.6 High High EngineeringTechnology Area


Cost Criticality Understanding

Opportunity

Classification

GDL Improved GDL Pore Structure 9 3 1 9 5.4 Med High High Priority ResearchGDL Freeze tolerant GDL Structure 1 3 3 1.9 Med Med ResearchGDL GDL Additive Materials 1 1 1 0.9 High Med EngineeringGDL GDL Additive Processes 1 1 1 0.9 Med Med EngineeringGDL GDL Degradation 3 0.6 Med Med EngineeringGDL GDL low Cost Substrate Materials 3 3 3 9 5.4 Med Med EngineeringGDL GDL Microporous Layer Process 1 1 0.7 Med High EngineeringGDL GDL Substrate Mfg Process 3 1.2 Med Med EngineeringGDL Improved Water Mgmt in GDL 3 3 1 9 4.8 Med High ResearchGDL Maximize GDL Stiffness 9 3 1 9 5.4 Med Low EngineeringGDL Minimize GDL Thickness 3 3 1 1.3 High Low Technoloy at LimitGDL More Conductive GDL 1 3 1.3 Med Low EngineeringMembrane Conductivity @ <20% RH 3 9 9 6.6 High Low Technoloy at LimitMembrane Conductivity @ >80% RH 3 3 3 2.4 High Med ResearchMembrane Conductivity @ 20% to 80% RH 3 3 3 2.4 High Med ResearchMembrane Fundamentally less expensive polymers 3 3 9 5.1 Low High High Priority ResearchMembrane Less expensive PFSA precursors 3 1.2 High Med EngineeringMembrane Low H2 Cross Over Membrane 3 9 3 4.5 Med Low ResearchMembrane Low N2 Cross over membrane 9 9 6.3 Med Low High Priority ResearchMembrane Manufacturing Process 1 3 1.4 High Med EngineeringMembrane Membrane Loss ( degradation) 9 1 2.2 Med Med EngineeringMembrane Minimize Membrane Thickness 1 3 3 3 2.8 High Low Technoloy at LimitTechnology Area


Cost Crit Under. Opp Classification

Plate Increased Plate Conductivity 3 1 3 1.8 High Low Technoloy at LimitPlate Precise Plate Mfg Tolerances 1 3 3 1.9 High Low Technoloy at LimitPlate Carbon plate Cycle Time 3 1.2 Med High EngineeringPlate Carbon raw materials Processing 3 1.2 Med Med EngineeringPlate Facile Liquid Water Removal 1 3 9 3 4.6 High Med High Priority ResearchPlate Improved Plate Formability 3 1 3 9 5 High Med High Priority ResearchPlate Increased Plate Strength 3 3 0.9 High Low Technoloy at LimitPlate Metal Coating materials/process 3 9 3.9 Low Med High Priority ResearchPlate Metal or Carbon Joining Method 3 9 4.2 Med Med EngineeringPlate Metal Plate Substrate Alloy 3 3 1.8 High Med EngineeringPlate Minimize Plate Web Thickness 3 3 1.5 High Low Technoloy at LimitPlate Plate Corrosion Resistance ( metal only) 9 3 3 Low Med High Priority Research

Stack Cost

Durability Fuel Economy

StrategicFilter

Technology Area

Driver Criticality Understanding Opportunity

Catalyst Carbon supported Pt 9 High LowCatalyst New High Activity Catalyst 9 Low HighCatalyst Less Platinum 8.2 High MedFCS Efficient Air Compressor Technology 7.2 High MedFCS ( vehicle) Less Gross Power 6.6 High HighMembrane Conductivity @ <20% RH 6.6 High LowCatalyst Pt Dissolution Resistant Catalyst 6.3 Med MedMembrane Low N2 Cross over membrane 6.3 Med LowFCS Less Expensive Humidifiers 6 Med HighGDL Improved GDL Pore Structure 5.4 Med HighGDL GDL low Cost Substrate Materials 5.4 Med MedGDL Maximize GDL Stiffness 5.4 Med LowMembrane Fundamentally less expensive polymers 5.1 Low HighPlate Improved Plate Formability 5 High Med

Critical Research Needs

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Strategic Filter

1. Criticality• The criticality is the sum of the magnitudes of all the effects (good

or bad) of using a technology path.

2. Understanding• A measure of how much we know about a technology option

• Advantages, failure modes and trade-offs

3. Remaining Opportunity

Impro

vem

en

t

Effort

• How much improvement remains to be made along each technology path.

• If a path is fully mature we reach the “Technology Limit” and further improvement will require a “breakthrough” or the exploitation of a different path.

Technology Limit

Opportunity

Status

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Map of the Technology Mine (Cost)

•Technology At Limit Exploit in present design: diminishing returns

•High Priority Research Focus of academic and corporate research

•Research Lower urgency research

•Development Engineering Focus of in house and supplier engineering

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The Biggest Driver for Materials

•Technology At Limit Exploit in present design: diminishing returns

•High Priority Research Focus of academic and corporate research

•Research Lower urgency research

•Development Engineering Focus of in house and supplier engineering

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Some Statistics

Technology at Limit23%

Research17%

High Priority Research

22%

Engineering 38%

Opportunity

med46%

low32%

high22%

Understanding

Medium38% Low

13%

High49%

1. We should focus on the 23% that are most critical.

2. Overall understanding of the opportunities is good.

3. There are many good opportunities for cost reduction

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The Most Critical Research

These areas of research and development need to be the focus.

New durable high activity catalysts.

Enable low cost system

Enable high current density via plate and GDL

Lower cost cell materials

12

3

4

11

1

1

2

22

2

3

3

3

2

4

4

Technology Area


Catalyst Carbon supported Pt 9 High LowCatalyst New High Activity Catalyst 9 Low HighCatalyst Less Platinum 8.2 High MedFCS Efficient Air Compressor Technology 7.2 High MedFCS ( vehicle) Less Gross Power 6.6 High HighMembrane Conductivity @ <20% RH 6.6 High LowCatalyst Pt Dissolution Resistant Catalyst 6.3 Med MedMembrane Low N2 Cross over membrane 6.3 Med LowFCS Less Expensive Humidifiers 6 Med HighGDL Improved GDL Pore Structure 5.4 Med HighGDL GDL low Cost Substrate Materials 5.4 Med MedGDL Maximize GDL Stiffness 5.4 Med LowMembrane Fundamentally less expensive polymers 5.1 Low HighPlate Improved Plate Formability 5 High Med

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The Mature Technologies

These technologies have reached their maximum capability.

• Gen 4 stack will utilize them at their maximum.

• It’s time to look for alternative paths or breakthroughs.

Technology Area


Catalyst Carbon supported Pt 9 High LowCell Design Self Hydrating Cell 4.2 High LowCell Design Robustness of design to MFG tols 2 High LowCell Design Minimize Port Areas 1.5 High LowCell Design Minimize transition areas 1.5 High LowCell Design Low Force Seals 1.5 High LowFCS Less Expensive Intercooler 0.4 High LowGDL Minimize GDL Thickness 1.3 High LowMembrane Conductivity @ <20% RH 6.6 High LowMembrane Minimize Membrane Thickness 2.8 High LowPlate Precise Plate Mfg Tolerances 1.9 High LowPlate Increased Plate Conductivity 1.8 High LowPlate Minimize Plate Web Thickness 1.5 High LowPlate Increased Plate Strength 0.9 High Low

FRM5101460

Examples and Targets

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Catalyst

Carbon Supports - High surface area carbon supported Platinum catalysts have been the main technology in automotive PEM for the generation 1,2 and likely 3 stacks however they have essentially reached the limits of performance and durability and new path need to be explored for generation 4.

Activity vs Durability - For Pt based structures mass activity can be enhanced by increasing the surface area or by altering the electronic structure of the surface. Both options need to be pursued but the impact on durability is critical.

Processing - During the development of new catalyst systems we need to simultaneously develop the processes to synthesize them at low cost and possibly to deposit them directly onto MEA with as few intermediate steps as possible to ensure high material yields.

Technology Area


Cost Criticality

Understanding

Opportunity

Classification

Catalyst Carbon supported Pt 9 9 9 9 9 High Low Technology at LimitCatalyst New high activity catalyst 9 9 9 9 9 Low High High Priority ResearchCatalyst Less platinum 1 9 9 9 8.2 High Med High Priority ResearchCatalyst Pt dissolution resistant catalyst 9 3 9 6.3 Med Med High Priority Research

Catalyst Non carbon catalyst support materials 9 3 3 3.9 Low High High Priority Research

Catalyst Catalyst coating technology 1 3 3 2.3 Med Med Engineering Catalyst Catalyst primary process 3 1.2 Low High ResearchCatalyst Freeze tolerant catalyst structure 3 1 1 Med Med ResearchCatalyst Catalyst recycling process 1 0.4 Low High Research

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Cathode Catalyst Pathways

StabilizedPlatinum Alloys

Catalyst-Support

Interaction(Non-Carbon)

Pseudo BulkCatalyst

Non PreciousMetal Catalyst

Proprietary Process

Support Structures

Thin film Pt-alloy Structures

Various Materials

High Surface Area Metal oxides

Core Shell Catalysts

Work Streams

Create stable alloys that retain high performance

Improve activity w/ more robust support materials

Replace platinum with w/ cheap catalytic materials

High activity & stability

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Mass Activity/ Specific Activity

C=Carbon; HSC=High Surface Area Carbon

Ex-situ Activity Summary normalized to Pt baseline

1.0 1.4 1.64.5

23.8

10.3

????

1

1.9 2.1

3.42.6

3.9

????

0

5

10

15

20

25

30

Pt/C b

asel

ine

Pt-allo

y "A

" HSC

Pt-allo

y Sta

bilize

d HSC

Pt Allo

y "B

"/C

Pt/Met

al O

xide

Pt-Met

al O

xide/

C

Adv C

ore

Shell

High S

urfa

ce A

rea

Oxide

Sp

ecif

ic A

ctiv

ity

0

1

2

3

4

5

6

Sp

ecif

ic M

ass

Act

ivit

ySpecific Activity ( x Pt baseline)

Mass Activity ( x Pt baseline)

4x Mass Activity Target

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Membrane

Driver PFSA membranes are quite mature and it is becoming apparent that further improvements will be limited. They are however quite capable and are expected to be viable in future generations when the cost of producing them is reduced significantly.

Cross-over - In order to enable cost reduction in the fuel cell support systems a large reduction in the Nitrogen cross over is needed. Unless a change in the basic polymer is used to achieve this thinner membranes may not be practical.

Hydration - A great deal of effort has been put into reducing the resistance of membranes at low RH however this has increased the basic cost of the materials. Fundamental studies have shown that zero RH conduction cannot occur for sulphonic acid based membranes.

Membrane Conductivity @ <20% RH 3 9 9 6.6 High Low Technoloy at LimitMembrane Conductivity @ >80% RH 3 3 3 2.4 High Med ResearchMembrane Conductivity @ 20% to 80% RH 3 3 3 2.4 High Med High Priority ResearchMembrane Fundamentally less expensive polymers 3 3 9 5.1 Low High High Priority ResearchMembrane Less expensive PFSA precursors 3 1.2 High Med EngineeringMembrane Low H2 Cross Over Membrane 3 9 3 4.5 Med Low ResearchMembrane Low N2 Cross over membrane 9 9 6.3 Med Low High Priority ResearchMembrane Manufacturing Process 1 3 1.4 High Med EngineeringMembrane Membrane Loss ( degradation) 9 1 2.2 Med Med EngineeringMembrane Minimize Membrane Thickness 1 3 3 3 2.8 High Low Technoloy at Limit

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Additive Technology

Low cost PFSA membranes

Hydrocarbon membranes

Block Co-polymer

Low cost SSC PFSA

Free Radical Scavengers

Water Retention Additives

Work Streams

Improve membranes by adding special function materials.

Lower membrane cost, improve performance & durability.

Cost and better gas cross over.

Homo polymer

Reinforcement

Low cost LSC PFSA

Membrane Pathways

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Dry Conduction Progress

Membrane resistances for different RH's

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1

0 20 40 60 80 100

Membrane RH (%)

Re

sis

tan

ce

(O

hm

.cm

2)

Supplier A

Supplier B

Supplier C

Target

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Dry Conduction Progress II Log Scale

Membrane resistances for different RH's

0.001

0.01

0.1

1

0 10 20 30 40 50 60 70 80 90 100

Membrane RH (%)

Re

sis

tan

ce

(O

hm

.cm

2)

Data from materials reported in the 2008 DOE Hydrogen program review

• Improved materials all have the same sensitivity to RH.• Overall resistance at all RHs improved• Without a change in conduction physics target at <30% RH unlikely to be met

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Proton dissociation –Needs Water

Vassiliki-Alexandra Glezakou, et.al. Phys. Chem. Chem. Phys., 2007, 9, 5752–5760

RSO3H : (H2O)n RSO3-+ H+(H2O)n

Based on these models for the equilibrium:

RSO3H : (H2O)n RSO3-+ H+(H2O)n

When n>3, the ion pair structure, RSO3-+ H+

(H2O)n is more stable than the neutral complex

(H2O)n. Ionization could happen.

• High proton transport rate in PFSA membranes requires a high degree ionization

• At RH <30%, the number of water molecules in a typical PFSA n 3.

• Insufficient water in the membrane can cause a low proton conductivity and poor durability

n=2 n=3

- +

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N2 Cross Over Effect on Parasitic Load

Nitrogen Cross Over

0

1

2

3

4

5

6

7

Target HC Block Co-Polymer

PFSA 1 (~25 um)

No

rma

lize

d t

o T

arg

et

Normalized H2 Pump Power

0%

20%

40%

60%

80%

100%

120%

0 0.2 0.4 0.6 0.8 1

Nitrogen Mole Fraction

% o

f Max

imum

The amount of gas that needs to be pumped back into the stack inlet is proportional to the nitrogen cross over rate.

The power required to pump this nitrogen is waste and requires extra cells to produce it.

The recycle circuit is typically purged to get rid of the accumulated nitrogen which inevitably wastes hydrogen.

Incremental improvements in nitrogen crossover directly benefit the cost and fuel economy of Fuel Cell Vehicles.

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Gas inlet: Ambient atmosphere , T 95 C

0

20

40

60

80

100

120

0 20 40 60 80 100 120

Cost US$/m2 (volum 850k m2 per year)

Mem

bra

ne

per

form

ance

& d

ura

bil

ity

Random HC polymer

Block HC polymer+ reinforcement

LSC PFSA+reinforcement

LSC PFSA

low cost SSC PFSA+reinforcement

SSC PFSA from Supplier C

SSC PFSA from Supplier D

HY5 target

lower cost

imp

rov

e p

erf

orm

na

ce

Cost-Performance Gaps

Gas inlet RH 30%, T 95 C

0

20

40

60

80

100

120

0 20 40 60 80 100 120


Me

mb

ran

e p

erf

orm

an

ce

& d

ura

bili

ty

Random HC polymer



LSC PFSA




HY5 target

lower cost

imp

rove

perf

orm

nac

e

Gas inlet RH 80%, T 85 C

0

20

40

60

80

100

120

0 20 40 60 80 100 120


Mem

bra

ne

per

form

ance

& d

ura

bil

ity

Random HC polymer



LSC PFSA




HY5 target

lower cost

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Bipolar Plates

Driver Plate technology is quite mature due to significant investment by researchers and a competitive environment with the suppliers. Plate assemblies can be made with good quality and strength at thicknesses well below 2mm and it is now the flow field and not plate material that limits further reductions.

Cost - While several suppliers are predicting cost which approach the targets, a significant gap remains with respect to joining/sealing methods, as well as corrosion protection coating technology and production cycle times.

Water Management - At high current densities much higher gas and liquid water fluxes must move through the channels. Water remains a big driver for flow resistance and poor flow distribution.

Technology Area


Cost Crit Under. Opp Classification

Plate Increased Plate Conductivity 3 1 3 1.8 High Low Technoloy at LimitPlate Precise Plate Mfg Tolerances 1 3 3 1.9 High Low Technoloy at LimitPlate Carbon plate Cycle Time 3 1.2 Med High EngineeringPlate Carbon raw materials Processing 3 1.2 Med Med EngineeringPlate Facile Liquid Water Removal 1 3 9 3 4.6 High Med High Priority ResearchPlate Improved Plate Formability 3 1 3 9 5 High Med High Priority ResearchPlate Increased Plate Strength 3 3 0.9 High Low Technoloy at LimitPlate Metal Coating materials/process 3 9 3.9 Low Med High Priority ResearchPlate Metal or Carbon Joining Method 3 9 4.2 Med Med EngineeringPlate Metal Plate Substrate Alloy 3 3 1.8 High Med EngineeringPlate Minimize Plate Web Thickness 3 3 1.5 High Low Technoloy at LimitPlate Plate Corrosion Resistance ( metal only) 9 3 3 Low Med High Priority Research

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Carbon or Metal: No Clear Winner

Coated Metal

Carbon Composite

• Inherently corrosion resistant.

• Conductive surface.• 200 um web thickness.

• Better FF, seal, and backside geometry possible.

Inherent Advantages

Needed Improvements

• Strength/toughness

• Process cycle time

• Raw material costs

• Low cost joining method

• High Strength/Toughness

• 100 um web thickness

• Inexpensive forming process

• Inexpensive substrate

• Coating Cost/Process

• Welding/joining cost

• Surface contact resistance plate to plate

• Available formed shapes.

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Pressure Drop Vs Water

2

2V

D

LfP Re

64f

22

Re)(

D

VLfP

VD

Re

Effect of Water on Pressure Drop and Apparent Friction Factor

64

74

84

94

104

114

124

134

0 50 100 150 200 250 300 350 400 450 500 550

Reynolds Number Vapour Included (Re)

f*R

e

Dry f*ReWet f*Re ~ 10 to 30 % more liquid waterAdvanced Flow Field #1 Wet Advanced Flow Field #2 Wet

For a smooth wall circular pipe

Gen 4 flow field advancements reduce pressure drop of advanced cells by ~30 %

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Power Density Progress

Stack Power Density and Cell Pitch

0

500

1000

1500

2000

2500

1990 1995 2000 2005 2010 2015

Year

Sta

ck V

olu

met

ric

Po

wer

Den

sity

(kW

/L)

0

1

2

3

4

Cel

l P

itch

(m

m)

Power Density (volumetric) Cell Pitch

Mk5 Mk7 Mk8 Mk901 Generation 1 Generation 2

Current density

Generation 3 Generation 4

Current density and cell pitch

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Conclusions

• There are many open paths to make further progress on Fuel Cell System costs.

• There has been a great deal of progress in many key areas: o Our understanding of the options is good.o There are quite a few mature technologies that can be

exploited in the generation 4 cars.

And thus:o Resources will be focussed onto paths with the most

remaining opportunity and highest impact on cost.

• This focussed research and engineering effort will enable us to meet commercial fuel cell targets

FRM 5101460 AFCC Research Needs Analysis for Generation 4 Vehicles.

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Transcript of FRM 5101460 AFCC Research Needs Analysis for Generation 4 Vehicles.