1. H2-O2 FUEL CELL
By Mrs. Anuja Kamthe

2. H2-O2 FUEL CELL FUEL CELL Introduction A fuel cell
Principle, construction and working
Advantage, disadvantage and application

3. 1. Introduction
What is fuel cell?
A fuel cell is a device that converts the chemical energy from a fuel into electricity through a chemical reaction with oxygen or another oxidizing agent.

4. Every fuel cell has two electrodes, one positive and one negative. The reactions that produce electricity take place at the electrodes
The Hydrogen Oxygen fuel cell transform hydrogen and oxygen into electric power, emitting water as their only waste product.

6. Electrical power production by fuel cell
Hydrogen
Oxygen

7. CONSTRUCTION H2-O2 Fuel cell
It consist of two inert porous carbon plates which are acting as cathode & anode
25% NaOH or KOH solution which is placed between the two electrodes is acting as an electrolyte.
Hydrogen gas is continuously bubbled at anode while Oxygen gas is continuously bubbled at cathode

8. Working
When Hydrogen gas reaches the anode surface the following oxidation reaction occurs:
H2 (g) + 4 OH - (aq) H2O(l)+ 4e-
The liberated electrons from anode then passes through the external circuit where work is performed, & then finally to the cathode where following chemical reaction takes place
O2 (g) + 2H2O(l) )+ 4e OH - (aq)
Hence Net reaction:-
H2 (g) + 2O2 (g) H2O(l)

9. 5. Advantage, disadvantage and applications
Advantages
Zero Emissions: a fuel cell vehicle only emits water vapour. Therefore, no air pollution occurs.
High efficiency: Fuel cells convert chemical energy directly into electricity without the combustion process. As a result, Fuel cells can achieve high efficiencies in energy conversion.
High power density: A high power density allows fuel cells to be relatively compact source of electric power, beneficial in application with space constraints.

10. Advantages
No Pollution: a fuel cell generators are free of noise, vibration,
thermal pollution.
Exchangable: Fuel cell systems are modular & hence parts can be replaced easily
Water : A. hydrogen oxygen fuel cell generates a drinking water of portable quality .(On Apollo moon flight this water was used by astronaut for drinking
Saves fossil fuel.
No recharge: Fuel cell systems do not require recharging.

11. Disadvantages
It is difficult to manufacture and stores a high pure hydrogen
It is very expensive as compared to battery
High cost of pure hydrogen
Life span of the cells are not accurately known
Lack of infrastructure for distributing hydrogen.
Liquification of hydrogen requirs 30% of the stored energy

12. Applications
Portable applications
They used in portable appliances and power tools
They can be used in small personal vehicles
They are used Consumer electronics like laptops, cell phones can be operated
They can be used in Backup power

13. 2. Transportation applications
They can be used for transport application in the following areas,
Industrial transportation
Public transportation
Commercial transportation (truck, tractors)
Marine and Military transportation

14. 3. Power distribution application
Fuel cells can be used for the distribution of power in various fields such as,
Homes and small businesses
Commercial and industrial sites
Remote, off-grid locations (telecom towers, weather stations)