Note that mine arrived with a small Philips head screwdriver, but you actually need a torx driver. Luckily I had one on hand from previous phone disassemblies...
I bought one of these - it took over a month to arrive but it appears to work well and is much higher capacity than the original.
http://www.ebay.com/itm/New-Portable-Replacement-Battery-for-Motorola-EB41-XT894-XT898-2850mah-Golden-/401138426325?hash=item5d65b6a1d5:g:DTkAAOSwvg9XY51u