1. How Batteries Work

2. A Battery  A battery is an electrochemical cell known as a voltaic cell --a chemical reaction releases moving electrons

3. Whats going on  The chemical reaction that generates electricity in a battery is known as oxidation-reduction reaction  OXIDATION – A substance loses electrons  REDUCTION – A substance gains electrons

4. 2 Types of Batteries  Dry Cell  Wet Cell  Both have electrolytes a liquid substance which acts as a medium to conduct electricity.

5. Wet Cell  A wet cell electrolytes are contained in a liquid.

6. A Dry Cell  A dry cells electrolytes are contained in a low-moisture paste.

7. Each Battery Contains - Anode-oxidator releases electrons - Anode-oxidator releases electrons + Cathode-reducer gains electrons These are known as electrodes

8. Separator or Bridge  Every Battery needs a bridge which prevents the buildup of excess charge at the two electrodes  Without the bridge the charge buildup at the electrodes would prevent the oxidation-reduction reactions from continuing

9. Normal A Battery

10. Batteries vs Wall Socket  Batteries produce Direct Current (DC)  Electrical Outlets produce Alternating Current (AC) where the electrons move back and forth

11. How do I recharge my phone  nickel-cadmium and lithium can be recharged  the chemical reactions in a rechargeable battery are reversible: when the battery is discharging the reactions go one way and the battery gives out power  when the battery is charging, the reactions go in the opposite direction and the battery absorbs power.