I know what you mean, Aviator. With tools that contain a lot of batteries, sometimes the cost doesn't "pencil out". These old electric screwdrivers have only either 2, ro 3 pak cells. At $1.50 each for AA size, the 3 cell cost is $4.50 which is quite tolerable. Another point, the LSD (low self discharge) can't deliver quite the current that Nicd, standard NmH, or Lipos can. I did this same LSD replacement with an old Craftsman cordless drill and though it works ok, the rpm is noticeably lower than it used to be. Cost, as Aviator said, was high, about $22. Cheap compared with Lipo, but rpm suffers. BUT, when I use it after storage, IT WORKS!

http://www.menards.com/main/electric...354-c-6309.htm

A little storybefore I did the replacement, I bought a little Lithium Ion screwdriver for $19 thinking I'd get around the NmH self discharging THAT way. But that screwdriver was geared way too high, the RPM was too high to really work well. It was WASTED money!

Now, BACK TO RC! These LSD batteries make GREAT flight and ignition packs! Charge, go to the field and fly, pack it up, and fly the following week WITHOUT TOPPING OFF the batteries!