Just finished building what is hopefully another half decent push
stick. The prior one, the yellow one (also pictured on my page),
worked well and was fun, but it needed a better battery. The
controller came unglued, so I took the opportunity to make another
push stick (actually three more, including two problematic
The current version with the red and black handle area uses a 5.5
amp hour lithium-ion weed eater battery. Need to practice with it,
but it should be the same as before. The battery includes a charge
level meter that should be useful when on the road.
These (videos of) inline skating push sticks are similar.
Good luck and have fun.