Oh right ok,
It's a 4x4 drill box (with a new weapon to be fitted but that's not hugely powerful)

I just that I used a 7500mah battery (it was a lead acid so that could be something to do with it) but that only lasted like three battles, and I figured a better battery with a higher discharge rate would out put more power so would last considerably less time, especially if you can't run it till its flat.

I'll look into the better battery's though, the only problem is my charge would take more than an hour to charge them so they may not be fully charged between battles? How do they cope with only being 3/4 charged? Would that be ok?