Science
How do batteries work?
Batteries work by converting stored chemical energy into electricity. A chemical reaction pushes electrons from one terminal (negative) to the other (positive) through your device, powering it along the way.
See it in motion.
Watch a 2-minute animated lesson that shows exactly how batteries works.
Step by step
- 1A battery has two electrodes (anode and cathode) and an electrolyte between them.
- 2A chemical reaction frees electrons at the negative terminal.
- 3Electrons flow through the circuit (your device) to the positive terminal.
- 4Rechargeable batteries reverse the reaction when charging.
Frequently asked questions
- What's inside a battery?
- Two electrodes (anode and cathode) and an electrolyte that lets charged particles move between them.
- How do rechargeable batteries work?
- Charging forces the chemical reaction to run backwards, restoring the stored energy.
- Why do batteries die?
- Repeated reactions degrade the electrodes and electrolyte, so they hold less charge over time.