Had a 9v screwdriver that would no longer take a charge. Was going to rebuild battery pack but it was custom fit for the handle (pita to replicate). I had a bunch of RC car batteries left over from days gone by so I put the two together. From two things I had no use for sprung forth a handy tool.
To make this work you'll need a battery pack. I used a 7.2 volt one I had laying around. You can pick them up on ebay for about7 or 8 bucks but you will need a charger. If like mine the charger circuit was shot. Yeah maybe I could have fixed that, but was above my pay grade. Mine was a 9 volt driver but the 7.2 battery works great.
Step 1: Open it up
I split it open and removed the battery pack. I laid the new pack in and cut one side of the handle as far as the current circuity would allow.