Batteries & fuel cells

Gives vivid description of batteries and fuel cells and their respective types

1. ELEMENTS OF ELECTRICAL ENGINEERING A PRESENTATION ON : - BATTERIES And FUEL CELLS Prepared by :- SHINDE ROHIT

2. Presentation’s content :- Batteries The Battery Connecting battery in series How a battery works? Disposable and Rechargeable Batteries The lead Acid Battery Tha Disposable Battery Fuel Cells Fuel cells How they works? About Fuel cells Fuel Cells to Replace Batteries Why Fuel Cells so Uncommon

3. Battery A cell consists of two electrodes of different metals immersed in a weak acid Multiple cells can be stacked in series to make a battery The positive terminal is called the anode and the negative terminal the cathode

4. Connecting Batteries in Series Batteries connected end to end will have a voltage equal to the total voltage of the individual batteries Disposable dry cell batteries have a typical voltage of 1.5 V + + + 1.5 V 3 V

5. How a Battery (Cell) Works Both electrodes slowly dissolve in the acid At the anode, electrons are used in chemical reactions as the metal dissolves At the cathode, electrons are absorbed into the electrode as the metal dissolves The net result is a buildup of electrons at the cathode

6. Disposable and Rechargeable Batteries A rechargeable battery can be connected to an electric current so that dissolved metals reform on the electrodes Examples: lead acid, nickel cadmium, lithium, etc. The chemical reactions that power a disposable battery cannot be reversed Examples: alkaline dry cells, etc.

7. The Lead Acid Battery Two electrodes, one of lead, the other of lead dioxide (PbO 2 ) immersed in sulfuric acid Lead ions ( Pb ++ ) dissolve, leaving two electrons behind Two electrons flow through the circuit and are used to help lead dioxide dissolve

8. Disposable Batteries A typical disposable battery contains a carbon (graphite) and a zinc electrode The electrolyte is a paste of ammonium chloride Disposable batteries may leak if too much of the zinc can is dissolved

9. Fuel Cells In a fuel cell hydrogen is “burned” by mixing with oxygen in such a way that it creates a voltage across two electrodes Only water is produced as a by-product Hydrogen can be fed in directly or as part of larger molecules such as methane (natural gas)

10. How They Work ? Hydrogen molecules give up their electrons to the first electrode Electrons pass through the circuit to the second electrode Electrons are returned to the molecules when hydrogen and oxygen combine to make water

11. About Fuel Cells Fuel cells have been around for 100 years Fuel cells can be made to burn other molecules, such as methane, propane, etc. Hydrogen can be extracted from gasoline before being fed into a fuel cell Fuel cells cannot store energy , so they must be used in conjunction with a storage battery

12. Fuel Cells to Replace Batteries Fuel cells can be used to power a laptop Micro fuel cells have been developed that are small enough to fit into a cell phone Fuel cells weigh less and last much longer than rechargeable batteries

13. Why are Fuel Cells so Uncommon? Methods are being developed to store hydrogen in a porous material rather than as compressed gas Fuel cells require expensive catalysts How do you pump compressed hydrogen at a self-service gas station? What happens to the hydrogen tank in an accident?

14. THANK YOU……