Hi Piglet,
They are MFA7 which are 12 volt 7 AH, but hey" there shit" they dont have enough cranking power, I just bought a new one and its the same, turns out its just to week to crank it over more than a few times.
Ive put a 47 tooth on both my daughters 200 and my 250 it is better, but most importantly it makes it a much better bike to ride not having to change gears every 60 feet!