I looked at battery space and stuff, but eventually settled with buying the batteries "Bac" recommends being camcorder batteries. I think it was a good decision I bought 2 battery packs for only 20$ with overall specs of 4400mAh and 7.6v(8.4v charged). Could have gotten 6600mAh if i bought another pack and would have only been 30$! Thats half the price of batteryspace.