So my eyes hurt from all the googling I have been doing tonight. I am modding my Z2 for warpless use and need to power it using something slightly smaller than the 4-AA pack. I know I can run parallel 9v, but I don't want to sacrifice lasting power if I can avoid it. Then I saw this video and it looks like the guy modded a small cell phone battery. Anyone know how that is done, or know of some easily modifiable rechargeable packs that I could drop in?