The document discusses fuel cells, including: 1) A fuel cell generates electricity through an electrochemical reaction between a fuel (typically hydrogen) and oxygen, with water and heat as byproducts. 2) Fuel cells have several types but all consist of an anode, cathode, and electrolyte; they operate by separating the fuel from the oxygen to prevent combustion. 3) Applications include stationary power systems, transportation such as fuel cell vehicles and buses, and portable power devices, with each fuel cell type suited to certain uses.

1. Shroff S.R. Rotary Institue of Chemical
Technology (SRICT)
• Name- RAJ PAREKH
• Branch- MECHANICAL,SEM-1
• Enrollment no-140990119029
• Topic- Introduction to fuel cells

2. What is a Fuel Cell ?
 Fuel and air react when they come
into contact through a porous
membrane (electrolyte) which separates
them.
 This reaction results in a transfer of
electrons and ions across the electrolyte
from the anode to the cathode.
 If an external load is attached to this
arrangement, a complete circuit is formed
and a voltage is generated from the flow
of electrical current.
The voltage generated by a single cell is typically rather small (< 1 volt), so
many
cells are connected in series to create a useful voltage.

3. A Fuel Cell Converts Chemical
Energy to Electrical Energy
Fuel
Hydrogen
Air or
Oxygen
Load
Anode Cathode
Electrolyte
e-
Catalyst Catalyst
H
+
Gas Diffusion
Layer
Gas Diffusion
Layer

4. Some History…..
Fuel cell principle first discovered
by William Grove in 1839.
Grove used four large cells, each
containing hydrogen and oxygen,
to produce electric power which
was
then used to split the water in the
smaller upper cell.
Composition of Fuel Cell
Anode
Cathode
Electrolyte
Catalyst

5. • About Anode
− Negative post of the fuel cell.
− Conducts the electrons that are freed from the hydrogen
molecules so that they can be used in an external circuit.
− Etched channels disperse hydrogen gas over the surface of
catalyst.
• About Cathode
− Positive post of the fuel cell
− Etched channels distribute oxygen to the surface of the
catalyst.
− Conducts electrons back from the external circuit to the
catalyst
− Recombine with the hydrogen ions and oxygen to form
water.
• About Electrolyte
− Proton exchange membrane.
− Specially treated material, only conducts positively charged
ions.
− Membrane blocks electrons.
• About Catalyst
− Special material that facilitates reaction of oxygen and
hydrogen
− Rough & porous maximizes surface area exposed to hydrogen
or oxygen

6. Working of Fuel Cells
• The Fuel gas (hydrogen rich) is passed towards the anode
where the following oxidation reaction occurs:
• H2 (g) = 2H+ + 2e-
• The liberated electrons from hydrogen in anode side do not
migrate through electrolyte.
• Therefore, they passes through the external circuit where
work is performed, then finally goes into the cathode.
• On the other hand, the positive hydrogen ions (H+) migrate
across the electrolyte towards the cathode.
• At the cathode side the hydrogen atom reacts with oxygen
gas (from air) and electrons to form water as byproduct
according to:
• The overall cell reaction is
H2 + 1/2 O2 +2e - H2O + Heat
fuel + oxidant product + Heat

7. Working of Fuel Cell
Electrical power
production by fuel cell
Rotating shaft connected to generator for
electricity production

8. Fuel Cell
Type
Electrolyte Anode Gas Cathode Gas Temperature Efficiency
Proton Exchange Membrane
(PEM)
solid polymer membrane hydrogen pure or atmospheric oxygen
75°C
(180°F)
35–60%
Alkaline
(AFC)
potassium hydroxide hydrogen
pure
oxygen
below
80°C
50–70%
Direct Methanol
(DMFC)
solid polymer membrane methanol solution in water
atmospheric
oxygen
75°C
(180°F)
35–40%
Phosphoric Acid
(PAFC)
Phosphoric Acid hydrogen
atmospheric
oxygen
210°C
(400°F)
35–50%
Molten Carbonate
(MCFC)
Alkali-
Carbonates
hydrogen,
methane
atmospheric
oxygen
650°C
(1200°F)
40–55%
Solid Oxide
(SOFC)
Ceramic Oxide
hydrogen,
methane
atmospheric
oxygen
800–1000°C
(1500–1800°F)
45–60%

9. Advantages/Disadvantages of Fuel Cells
• Advantages
− Water is the only discharge (pure H2)
• Disadvantages
− CO2 discharged with methanol reform
− Little more efficient than alternatives
− Technology currently expensive
• Many design issues still in progress
− Hydrogen often created using “dirty” energy
(e.g., coal)
− Pure hydrogen is difficult to handle
• Refilling stations, storage tanks, …

10. Each type of fuel cell is particularly suited to
certain applications:
• PEM: most versatile, used for portable power,
transportation, and stationary power
• DMFC: used for portable power
• SOFC: primarily used for stationary power, in
development for transportation (e.g. semi trucks)
• MCFC: power plants
• AFC: power and water production for space
vehicles (e.g. Apollo and Space Shuttle
spacecrafts), in development for more general use
• PAFC: stationary power, power plants

11. Galvanic cell (battery)Hydrogen fuel cell
Open system
Anode and cathode are gases in
contact with a platinum catalyst.
Reactants are externally supplied,
no recharging required.
 Closed system
Anode and cathode are metals.
Reactants are internally consumed,
need periodic recharging.
Fuel Cell Vs. Battery
Basic operating principles of both are very similar, but there are several
intrinsic differences.

12. Fuel Cells in Use: Stationary Systems

13. Fuel Cells in Use: Stationary Systems
Fuel cell system for submarine

14. Fuel Cells in Use: Transportation Systems
XCELLSiS fuel cell bus prototypes
Buses are most commerciall
advanced applications of fue
cells to date.
Are currently being used by
many American and Europea
cities.

15. Fuel Cells in Use: Transportation Systems
Many of the major car companies are developing fuel cell car prototyp
which should come to market during the next decade. The cars use eith
pure hydrogen or methanol with an on board reformer.

16. 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)

17. SOLAR FUEL CELLS ?

18. THANK YOU