How about a UPS battery?
I got mine from Maplin.
Fully charge your packs night before, then just top up trackside.
1.2Ah one easily does me. I've got 3 lipos in 2wd. Even if I take 2000 mah out that's 6000 so half the UPS battery. Much smaller than a leisure battery and lighter too.
__________________
:: AE B5MCE - SP 7.5 v3.0 Brushless Motor - Reedy Shorty Lipo - Savox Servo - Spektrum Rx ::
:: Paint By Turnip Paint ::
|