Cordless batteries eventually fail, but replacement batteries can be quite expensive, especially for older models. To save money, look into rebuilding the battery.
By the DIY experts of The Family Handyman Magazine:May 2002
To rebuild a battery, the cells inside the housing have to be replaced by a battery rebuilder.
Replacing a dead battery for an old cordless drill can sometimes be a problem. First, find a factory-authorized service dealer (check online or contact the manufacturer) and ask about the replacement price. Brace yourself; it might shock you. A new 12-volt battery for an old drill of mine was almost half the price I'd originally paid for the drill. Next I called a battery dealer. They quoted me a price of about a third less to rebuild the battery, including a six-month warranty. Rebuilding consists of opening the battery pack and replacing the ten 1.2-volt cells (10 times 1.2 volts equals 12 volts) with new ones.
Find rebuilders online or in the Yellow Pages under “Batteries.” They'll tell you if they can do the job. If the drill is still working well, I'd rebuild the battery pack.
Have the necessary tools for this DIY project lined up before you start—you’ll save time and frustration.
Avoid last-minute shopping trips by having all your materials ready ahead of time. Here's a list.
