I've been searching around for some rechargeable 36V battery packs and I can't seem to find one under $200. I found drill batteries are inexpensive and are 18V with 3AH. On top of that I wouldn't need to buy a charger. I could get 4 18V 3AH batteries for around $70. The only thing I'm worried about is that they might not be able to supply the amperage needed to the motors. They seem pretty powerful considering that the drill motors have pretty high torque. Do you think they can supply the amperage necessary to power the two 36V 190KV motors, or do drills just have a really good gearbox that creates most of the torque?

  • \$\begingroup\$ Drills do indeed have a good gearbox for the high torque setting. \$\endgroup\$
    – user16324
    Commented Jan 7, 2021 at 21:16
  • \$\begingroup\$ A big problem is I don't know the chemistry of the drill batteries. A lot of them just say lithium. \$\endgroup\$
    – Jacob Lara
    Commented Jan 7, 2021 at 21:19
  • \$\begingroup\$ You should probably figure out what your current demands are and getting a battery specced to do that. You haven't really told us how much current you think you need. Frankly, your easiest path for something like this would be to find somebody who has done something similar and do what they did. \$\endgroup\$ Commented Jan 7, 2021 at 22:05
  • \$\begingroup\$ Look at the capacity (AH) rating for that 36V mountain board pack. If it's significantly higher than 3AH, then even if your drill batteries do provide enough current, they won't do it for long. \$\endgroup\$
    – TimWescott
    Commented Jan 9, 2021 at 19:00

1 Answer 1


Electric drill motors are geared down to give high torque at relatively low speeds.

You don't give a specification for your motors. But it looks like they draw tens of amps (for example one listed on Amazon draws 24 to 65A. Four battery packs wired in series/parallel only gives 36V 6AH.

Your batteries are only going to last a few minutes at that current, as they will be grossly overloaded. There's also a risk they will overheat and catch fire.


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