demonstrations:12v_car_battery_dissection
12V Car Battery Dissection
Materials: ★★★ Requires materials not commonly found in school laboratories
Difficulty: ★★★ Requires a more experienced teacher
Safety: ★★★ Only to be attempted with adequate safety procedures and trained staff
Categories: Electrochemistry
Alternative titles: Lead-Acid Car Battery Structure
Summary
A car battery is a lead-acid electrochemical cell that converts chemical energy into electrical energy. It consists of lead plates and sulfuric acid electrolyte, which react to provide the current needed to start a vehicle and power its electrical systems.
Procedure
- Observe the structure of a lead-acid car battery, which contains six cells producing about 2.1 volts each, for a total of ~12 volts.
- Identify the positive and negative plates made of lead compounds.
- Note the sulfuric acid and water electrolyte that reacts with the plates to generate electricity.
- Locate separators, which prevent direct contact between plates while allowing ionic flow.
- Trace how the connectors, grids, and terminals direct the flow of electricity to the vehicle’s starter and accessories.
- Understand that when the car is running, the alternator recharges the battery by reversing the chemical reaction.
Links
Hacking Open A Car Battery (for Lead and Acid) - TKOR:
📄 Anatomy of Car Battery - auto batteries: https://www.autobatteries.com/how-batteries-work/anatomy-of-car
Variations
None
Safety Precautions
- Always wear safety glasses and gloves when handling car batteries.
- Sulfuric acid is highly corrosive; avoid spills and neutralize with baking soda if they occur.
- Batteries can release hydrogen gas—keep away from sparks or flames.
- Lift carefully; car batteries are heavy and can cause injury.
- Dispose of or recycle batteries through proper hazardous waste or recycling programs.
Questions to Consider
- Why does a 12-volt car battery contain six separate cells? (Each cell produces ~2.1 volts, and six in series provide ~12.6 volts.)
- What chemical reaction allows the battery to generate electricity? (The lead plates react with sulfuric acid to produce lead sulfate, water, and electrons.)
- Why does heat shorten battery life? (High temperatures accelerate chemical breakdown and corrosion of the plates.)
- How does the alternator keep the battery charged? (It supplies an electrical current that reverses the discharge reaction, converting lead sulfate back into lead dioxide and lead.)