The old Bosch PSR960 battery was certainly dead. Not a big surprise as I have not used and charged it correctly all the time. I have pondered buying a new battery but the price of a battery was almost as high as for a new tool.
I had some spare NiMH batteries and a holder for them so I decided to build a new battery for the drill. Using NiMH is better than LiIon because I can reuse the same charger although LiIon would probably be more powerful and lighter. Even with NiMH I boosted the capacity . from 1500 mAh to 2500 mAh
I removed the old NiCd cells and cut the bottom of the battery in order to make room for the holder. I have soldered the wires to the pack and placed the heat sensor on a cell. To keep them from moving (and be able to replace a cell if it would be the case I fixed them in place with some silicone.
It worked... I have a working screw driver.
