Need suggestions for a Sondors dual battery conversion.

Chris Zanotti

New Member
Hey everyone,

I was wondering if you could suggest some guidance for wiring two batteries onto one Sondors fat bike? I have a running bike, and I can mount a small spare battery anywhere.

However I am weak on wiring, and I don't want to set the bike on fire.

Anyone done this before?

Anyone want to show off?

Thank you!



Well-Known Member
Weak on wiring? Don't do it then. The safe way is to stop, disconnect battery 1, and then connect battery 2.

Running two batteries in parallel is no big deal when they are flashlight batteries, but when you have two powerful units of 40Volts or more, big currents can flow if you connect them together unless they are at the same voltage. You really need to understand battery technologies too. Can't mix certain types, ever. If you wish to use a switch, it has to be a pretty hefty one to handle the current from one battery. Sure, people do this all the time, but it's not as simple as it looks.


Well-Known Member
Weak, good, or great skills, every good battery pack maker will negate your warranty for doing that. A switch would be a better option, but there are very very few that are up to spec.