Why does a non-rechargeable battery run out after powering a device?
Show answer & explanation
Answer: Its energy-releasing chemicals change into discharge products
It loses a supply of loose electrons stored inside — A battery is not a container of loose electrons that gradually empties. Chemical reactions drive electrons around the external circuit while ions move inside the battery. Once the cell cannot sustain that process, the device stops working.
Its outer metal contacts must completely rust away — A battery can run out even when its contacts are clean and intact. Corrosion can cause a separate connection problem, but ordinary discharge changes the chemicals inside the cell.
Its energy-releasing chemicals change into discharge products ✓ — Discharge uses chemical reactions that turn stored chemical energy into electrical work. As the materials change, the battery eventually cannot sustain enough voltage and current for the device. That does not mean every last bit of reactant has vanished.