This is how i take them apart.
cutting wheel on a dremel and i make a slice going length ways. The cover is only .010 thousandths of a inch thick so you dont have to cut very deep.
i just pry the tube open with a little screwdriver. The battery ground is soldered to the end cap just yank it off and the guts slide out.
Thats pretty much all there is too it. This was a bad battery that ab357 sent to me. Looks like one of the diodes on the protection/mosfet circuit board is fried.