If the battery is a AA or AAA rechargable replace with the newer type NI-MH
instead of NI-CAD. NI-MH
doesnt get the memory effect. Look at the ma rating (milli amp). The higher the number the longer it should go on a charge. Some are out there with a 2400ma rating. Just a few years ago 1600ma was the highest.
Batterys still have power even if the camera will not work. Cameras are energy hogs and shutdown at a set level. The batterys will still run a walkman or other low power device for a few hours or even longer. Running down NI-CADs like this before charging will increase the life.
Some cameras have special batterys that only work in there brand stuff. They may be NI-MH
or Lithium Ion. Not much you can do then but buy another of THERE batterys. Most cell phones are Lithium Ion type.