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What is the lifespan of a water battery?

Water and electricity don’t mix, or at least that is what we’ve been told, right?

Asked by: David Williams, Lytham St Annes
Batteries convert chemical energy into electricity using electrolytes. These are ionised fluids whose molecules have a net electrical charge. Water batteries contain powder that becomes an electrolyte when water is added. They have a life of about 1000mA hours, meaning a 10mA LED can be run continuously for about 100 hours.

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