Batteries generate electricity by chemical reactions that move electrons from one terminal to the other. Ordinary alkaline batteries use a potassium hydroxide gel as the conductive electrolyte, and the reactions in the gel generate a small amount of hydrogen gas.
Since the battery is sealed, the pressure in the cell gradually builds and eventually causes tiny ruptures along the seams of the metal casing. The potassium hydroxide reacts with CO2 in the air to form a harmless crust of potassium carbonate, but the potassium hydroxide itself is caustic and can cause skin irritation. Take your leaking batteries to the recycling centre in a plastic bag.
Read more:
- How do solid-state batteries work?
- How are batteries recycled?
- Why do batteries explode?
- Why can’t you recharge batteries instantly?
Asked by: Lucinda Cox, Sussex
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