1. C5 - Fuel CELLS AND rechargeable Batteries nathan marshak

2. Instead of recharging, you add fuel Lower environmental impact Expensive. FUEL CELLS Secondary cells are rechargeable. Store small amounts of energy Cheap. BATTERIES C.5.3 - DESCRIBE HOW A HYDROGEN-OXYGEN FUEL CELL WORKS

3. C.5.1 - DESCRIBE HOW A HYDROGEN-OXYGEN FUEL CELL WORKS REACTION FOR ACIDIC ELECTROLYTE (e.g. Phosphoric Acid) Positive: 2O 2 + 4e - + 4H + --> 4H 2 O Negative: 4H 2 --> 4H + + 4e - Overall: 2H 2 + O 2 --> 2H 2 O

4. C.5.1 - DESCRIBE HOW A HYDROGEN-OXYGEN FUEL CELL WORKS REACTION FOR BASIC ELECTROLYTE (e.g. NaOH) Positive: H 2 + 2OH - --> 2H 2 O + 2e - Negative: O 2 + 2H 2 O + 4e - --> 4OH - Overall: 2H 2 + O 2 --> 2H 2 O

5. Nickel-Cadmium Battery C.5.2 - DESCRIBE THE WORKINGS OF RECHARGEABLE BATTERIES

6. Nickel-Cadmium Battery C.5.2 - DESCRIBE THE WORKINGS OF RECHARGEABLE BATTERIES REACTION AT NEGATIVE ELECTRODE (CADMIUM) REACTION AT POSITIVE ELECTRODE (NICKEL) OVERALL REACTION

7. C.5.2 - DESCRIBE THE WORKINGS OF RECHARGEABLE BATTERIES Used in cars to start it. Battery charges while car is running. Amount of charge left can be measured Heavy Lead Acid Battery

8. C.5.2 - DESCRIBE THE WORKINGS OF RECHARGEABLE BATTERIES

9. Lighter than NiCd Consumer devices More voltage than NiCd, Shorter lifespan than NiCd Lithium-Ion Battery

10. C.5.2 - DESCRIBE THE WORKINGS OF RECHARGEABLE BATTERIES Lithium-Ion Battery Positive: LiCoO 2 --> Li 1-x CoO 2 + xLi + +xe - Negative: C + xLi + + xe - --> CLi x Overall: LiCoO 2 + C --> Li 1-x CoO 2 + CLi x

11. CHARGINGDISCHARGING C.5.2 - DESCRIBE THE WORKINGS OF RECHARGEABLE BATTERIES