Okay, where can we get the 7.2 volt battery?
You can purchase a battery from Innovation First or build your own from a 7.2 volt rechargeable battery that can be found at many hobby stores. If you choose the latter solution, you’ll need to purchase a new connector housing (P/N A1411-ND) and female contacts (P/N A25562-ND) from Digi-Key. BTW, if you’d like to build a battery extension cable, Digi-Key has the mating connector housing (P/N A1410-ND) and male contacts (P/N A25561-ND) too.