You can probably use a sealed, pre-made battery for a 1/18, Mini-Z,Tamtechcar,some type of long &flat radio receiver battery pack, or evenbuild one from individual cells. The original battery required is only a 7.2V 600mAh Ni-CD. With so many types of batteries nowadays, something like Ni-MH, Li-Po, Lion, or Life, with a higher voltage and mAh will be suitable for more powerandlonger playing time, depending on your ESC.