Why can't you recharge batteries instantly?

22nd July 2009

Asked by: Kenny Millar, Kirkintilloch

When you recharge a battery you're replacing the electrons it released to power your gadget. But, like cars squeezing along a busy road, there is a limit to how many electrons can flow through the connectors, so you couldn't simply recharge the battery instantaneously. The other limitation is heat - the higher the charging current, the hotter the battery and charger.