why do batteries run down when you aren't even using them?

Question

so whenever i come to use my camera th batteries are flat!

Answer 1

Batteries are basically stored energy, and this energy can leak away, even when not in use. Wikipedia can explain it better than me:

"This is known as the "self discharge" rate and is due to non-current-producing "side" chemical reactions, which occur within the cell even if no load is applied to it. The rate of the side reactions is reduced if the batteries are stored at low temperature, although some batteries can be damaged by freezing. High or low temperatures will reduce battery performance.

Rechargeable batteries self-discharge more rapidly than disposable alkaline batteries; up to three percent a day (depending on temperature). Due to their poor shelf life, they should not be stored and then relied upon to power flashlights or radios in an emergency."

Answer 2

Im not sure on the technical reason, but I know, especially with rechargeable batterys, something about how they work makes this discharge over time when they are left unused.

This happens with normal batteries too, but over years, not days/weeks like rechargeables.

Answer 3

Nothing is isolated, even if u fill air in tyre of car.........it gets redeced day by day...bcoz of small amount of leakage

same for Batteries...............batteries have internal resistance which itself causes current to flow and bcoz of that reason it gets flat even u dont use it. :)