Lectures

I Introduction to Battery and Fuel Cells

A What is an electrochemical cellB Batteries Energy and Powerdensity efficiency

C Fuel Cells Phosphoric acidFuel Cell AKalineFuelCell

I A Electrochemical cell

Cats Two electrodes cathode and AnodeWE and CE if peoplewant tostudy thekinetic at one electrode

Electrolyte glowg ionsExternal conductor glowgelectrons

external circuits

Representation

DÉITE

Electrode mobilespecies electrons conductivity to to to stemeg Metal semiconductor

Electrolyte mobilespecies ionsMoelectrons conductivity to toto stem

eg dissociated salt moltensalt polymer Mayion FAA

Digerencebetweenelectrochemicalreactionandchemicalreation

Electrochemical run chemical rane

Ha 102 HDHffito

DAnode Cathode

generateelectricity generate heat

tf to

electron pass throughpotential differencebetween twonuclei

electronpass throughpotential difference between2 electrodes

B Batteries

A self contained electrochemicaldevicewhich storeselectric

energy

Discharged reaction LiCe t 2hi Coo Ce t 2hiCoq

CathodeAnd

tDT e

graphite

somekindofoxide electrolyte can be some sortof

ethylene carbonate

Primary Non rechargeable

Secondary Rechargeable

Metric

where Q1FMmemoles greactant beingconsumed

electrons

foreachreactant

teas

etime

eg 3 I means the cell is fullydischarged in f hour

Epicencydischarge Columbia

On a charge basis go 81change

Efficiency

On an energy basis 9 8É

Examplesof battery

Primary

Levanche 2ndMnai I

Secondary

i t111

I 1 I 1 ICFuelCells_An electrochemical cell which converts chemicalenergy of a

fuel into electricity Not self contained device

Typically O and Halcyon M based substancesHarnessenergy from oxidation reaction

Example Ha10 fuel cell

FI IT ccathode

Tete

Halo fuel cell can operate in acid or basic conditions

phosphoric acid fuel cellalkaline fuel cell

PEM fuel cell AAEM fuel cell

filly available

EDE is typicallymade upof Pt C on carboncloth

POIs Disadvantage ORR is

i

Thwinaadiccondition

Basic conditionGDE can be non precio

KOH metal

j ÉÉ4th Disadvantage AEMhas

1 low ionic conductivityCd accumulation ifOzis taken fromambient air