Litium ion battery 28v at a local dealer here in Maine is 125 bucks or so. I imagne they can be had for alittle over a 100 online somewhere.
Anyone see the car they made on Discoveries Monster garage powered by a few hundred 28v Milwaukee batteries [Linked Image]. The battery cost was unreal, can't remember the exact figure. The car went well though, 94 mph, 1/4 mile