The document provides an overview of fuel cells, including their construction, working principles, types, and applications. It describes different fuel cell technologies such as phosphoric acid, alkaline, proton-exchange-membrane, direct-methanol, molten-carbonate, and solid-oxide, highlighting their efficiencies and operating conditions. Additionally, it discusses the advantages and limitations of fuel cells, emphasizing their potential for transportation, stationary power, and micro power applications.

1. FUEL CELL AND IT’S
MICRO- APPLICATIONS
A Presentation By:-
Mihir Kulkarni
10CH027
Manas Orpe
10CH030
Guided By:-
Prof. P.N. Dange
Schematics of reactant flow in a MCFC

2. WHAT IS A FUEL CELL?
 It is a galvanic cell or electrochemical power
source
 it generates electrical energy with water and heat
as its by-product
 both the reactants and the products are liquids or
gases

3. CONSTRUCTION & WORKING OF A FUEL CELL
 Has two electrodes, anode and
cathode
 An electrolyte, which carries
electrically charged particles
from one electrode to the other
 A catalyst, which speeds the
reactions at the electrodes.
 Overall reaction is split into two
partial reactions : oxidation and
reduction

4.  Process begins when Hydrogen molecules enter anode
 Catalyst coating separates hydrogen’s negatively charged electrons
from the positively charged protons
 Electrolyte allows protons to pass through to cathode, but not
electrons
 Instead electrons are directed through an external circuit which
creates electrical current
 Oxygen molecules pass through cathode
 Oxygen and protons combine with electrons after they have
passed through the external circuit
 Oxygen and protons combine with electrons to produce water and
heat
CONSTRUCTION & WORKING OF A FUEL CELL

5. TYPES OF FUEL CELL
1] Phosphoric acid fuel cell (PAFC)
 Electrolyte is phosphoric acid
 Efficiency is 40 to 80 percent
 Operating temperature –
150 to 200oC (300 to 400o F)
 Output - up to 200 kW
 PAFCs tolerate a carbon
monoxide concentration of
about 1.5 percent

6. 2] Alkaline fuel cell (AFC)
 Operate on compressed
hydrogen and oxygen.
 Generally use solution of
potassium hydroxide (chemically
KOH) in water as their
electrolyte.
 Efficiency is about 70 percent
 Operating temperature is 150
to 200o C, (about 300 to 400o F)
 Cell output ranges from 300
W to 5 kW.

7. 3] Proton-exchange-membrane fuel cell (PEMFC)
 Work with a polymer electrolyte in
the form of a thin, permeable sheet
 Efficiency is about 40 to 50 percent
 Operating temperature is about 80o C
(about 175o F)
 Cell outputs generally range from 50 to
250 kW.
 Reactions :
Anode (oxidation): H2  2H+ + 2e-
Cathode (reduction): ½ O2 2H+ +2e-  H2O
Overall : H2 + ½ O2  H2O

8. 4] Direct-methanol fuel cell (DMFC)
 Specific content of
chemical energy of about
6 kWh/kg
 Operating temperatures
are in the range
50-120 C,
 Power outputs between
25 watts and 5 kilowatts
 Reactions :
Anode (oxidation) : CH3OH + 60H-  5H2O + 6e- + CO2
Cathode (reduction) : 3/2 O2 + 3H2O + 6e-  6OH-
Overall : CH3OH + 3/2 O2  CO2 + 2H2O

9. 5] Molten-carbonate fuel cell (MCFC)
 Use high-temperature
compounds of salt (like sodium or
magnesium) carbonates
(chemically CO3) as the electrolyte
 Efficiency ranges from 60 to
80 percent
 Operating temperature is about
650o C (1,200 o F)
 Output upto 2 megawatts (MW)
 Reactions :
Overall reaction : CO + ½O2  CO2
Oxidation reaction : CO + CO3
2-  2CO2 + 2e-
Reduction reaction : ½O2 + CO2 + 2e-  CO3
2-

10. 6] Solid-oxide fuel cell (SOFC)
 Use a hard, ceramic compound
of metal (like calcium or
zirconium) oxides (chemically, O2)
as electrolyte
 Efficiency is about 60 percent
 Operating temperatures are
about 1,000o C (about 1,800 o F)
 Cells output is up to 100 kW
 Reactions :
Reduction reaction : ½O2 + 2H+ + 2e-  H2O
Oxidation reaction : H2  2H+ + 2e-
Overall reaction : H2 + ½O2  H2O

11. APPLICATIONS
 Transportation
 Stationary Power Stations
 Telecommunications
 Micro Power

12.  Transportation : All major automakers are working to
commercialize a fuel cell car.Automakers and experts speculate
that a fuel cell vehicle will be commercialized by 2010.
 Stationary Power Stations : Over 2,500 fuel cell systems have
been installed all over the world in hospitals, nursing homes,
hotels, office buildings, schools and utility power plants.
 Telecommunications : Due to computers, the Internet and
sophisticated communication networks there is a need for an
incredibly reliable power source. Fuel Cells have been proven to
be 99.999% reliable
APPLICATIONS

13. APPLICATIONS
 Micro Power :
• Consumer electronics could gain drastically longer
battery power with Fuel Cell technology.
• Cell phones can be powered for 30 days without
recharging.
• Laptops can be powered for 20 hours without
recharging.

14. ADVANTAGES
 Physical Security
 Reliability
 Efficiency
 Environmental Benefits
 Battery Replacement/Alternative
 Military Applications

15. ADVANTAGES
 Physical Security : Both central station power generation and
long distance, high voltage power grids can be terrorist targets in
an attempt to cripple our energy infrastructure.
 Reliability : Properly configured fuel cells would result in less
than one minute of down time in a six year period. U.S.
businesses lose $29 Billion a year from computer failures due to
power outages.
 Efficiency : Because no fuel is burned to make energy, fuel cells
are fundamentally more efficient than combustion systems.

16. ADVANTAGES
 Environmental Benefits : Fuels cells can reduce air pollution
today and offer the possibility of eliminating pollution in the
future.
 Battery Replacement/Alternative : Fuel Cell replacements for
batteries would offer much longer operating life in a packaged of
lighter or equal weight.
 Military Applications : Fuel Cell technology in the military can
help save lives because it reduces telltale heat and noise in
combat.

17. LIMITATIONS
Economic Problems :
 Manufacturing cost of fuel-cell power plants is very high.
 The most important components of all p.e.m.f.c. and d.m.f.c.’s is
very expensive, about 700 $/m2.
 Total cost of a 5-kW p.e.m.f.c power plant is be about 1200 $/kW.
 In comparison cost of an analogous I.C. engine is 500-1500 $/kW.

18. LIMITATIONS
The Problem Of Lifetime :
 Satisfactory lifetime for smooth operation.
 3 years lifetime for small plants in portable devices.
 5 years for electric vehicles.
 10 years for large stationary multi-megawatt power plants.
 Samples of single p.e.m.f.c and stacks have been successfully
operated for several thousands of hours.
 But not enough data available for general use of these type of fuel
cells.

19. RENEWABLE ENERGYACT : FOR INDIA'S FUTURE NEEDS
 Solar water heating to be made mandatory throughout the urban
areas of the country by 2012, in a phased manner.
 Widespread application of co-generation concepts (heat and
power) for lighting, heating and cooling

20. REFERENCES
 Fuel Cells: From Fundamentals to Applications, S. Srinivasan,
Springer, New York, 2006
 Fuel Cell History Part 1, G. Wand, “Fuel Cell Today” June 16,
2006
 Handbook of Fuel Cells: Fundamentals, Technology, Applications
(four volumes), W. Vielstich, A. Lamm, and H. Gasteiger (editors),
Wiley, Chichester, UK, 2003
 "Confusion and Controversy: Nineteenth-Century Theories of the
Voltaic Pile," pp. 133-157 in F. Bevilacqua and L. Fregonese,
 Nuova Voltiana: Studies on Volta and his Times, vol. 1 (2000)