Most cameras today use rechargeable batteries. While it is said that lithium ion and such types of batteries can ideally last a lifetime, there are several things you may be doing that are quickly hastening this said lifetime. Here are some tips to extend your camera battery's life.
Camera batteries should never be stored at high temperatures. All manufacturers have specific instructions on the packs regarding this. Unfortunately, not everyone gets into the habit of enjoying the manufacturers' literature and getting these instructions.