Why is there a difference in performace between manufacturer and generic batteries?

Question

I bought a generic Li-Ion battery for my OLYMPUS EVOLT E-510. camera. It was rated at 7.2 volts and 1500 mAh which is what original Olympus battery is rated for.

It lasted a fraction of the time my original Olympus battery (BLM-1) before requiring recharge. Thinking it was a bum battery, I bought another and the same thing happened?

Original Olympus batteries cost over $40 whereas generics cost $16.

Anyone else had a bad experience with generics?

Answer 1

Original batteries for all the major camera manufacturers have electronics on board that control the power used by your camera, so it is used most effectively.  There is a distinct possibility that a generic battery will over heat when being charged (because the do not have the proprietary control circuits on board) which can not only shorten the batteries life (as well as you have found, charge holding) and in some unusual cases cause a fire or even explode.

Think of the extra $22 as insurance.