Why can I get more power out of a dying battery by taking it out then reinserting it? © Getty Images

Why can I get more power out of a dying battery by taking it out then reinserting it?

Scrooge McDuck spent an inordinate amount of time pacing around his mansion reinserting empty batteries into his appliances.

Asked by: Daniel McLaughlin, Pudsey

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A battery uses a chemical reaction between two materials to produce electrical charge. What you’re seeing are its last gasps as the energy from the electrochemical reaction peters out. When you disconnect the battery, a small amount of charge trickles to the terminals. It’s enough for a momentary surge of voltage when you reinsert it. But, by now, the dying cell is too lacklustre to sustain the flow of charge.


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