Phosphoric Acid Fuel Cell(PACF)

PAFC-1980

Supply For Electrode:

Positive-oxygen (or) air

Pores-Electrolyte &Electrode get a contact in electrochemical reaction

Catalyst-accelerate

the reaction

Platinum-best catalyst for both

electrodes & premium fuel cell.

Nickel-negative electrode

Silver-positive

electrode

Catalyst-platinum/nickel/silver

deposited on the outer surface.

During the usage of cell the

catalyst gradually lost its activity.

Inactivaion-impurities(sulphur) in the fuel

At the Negative electrode:

Hydrogen gas

Hydrogen ions+electrons

H2 2H+ +2eˉ

Electrons from negative electrode flow through the external load to

positive electrode.

H+ ions migrate

negative to positive through

electrolyte.

On reaching the positive electrode-

interact with O2 to produce

water.

½ O2+2H+ +2eˉ

H2O

H2+1/2 O2

H2O

Operating temperature=150°C-

200°C

At Atmospheric Pressure the ideal emf of

1.23V at 25°C –

reduces to 1.15V at 200°C.

The actual value less than this & decrease

with current

Rated value of current-voltage

lies between

0.7V-0.8V.