What BMS Amperage & manufacturer best suited?

I am building my first battery pack, a 12s4p molicel 21700 with a stormcore 60 ESC and have a BMS question. I’m thinking I may want to get a smart BMS mainly to see how hot the battery is getting. Is the LLT the best option and which continuous charge model would I need? I’m planning on 6374 motors and they have a max amperage of 85A, does that means the BMS needs to be that amperage X2 at 190??? I know it a noob question but I’m a bit confused on what continuous amperage the BMS needs to be, seems like 20A is the stanard, but It can’t hurt to have a bit extra and go with a 30A BMS model, right? Am I thinking correctly on this? Any help much appreciated!!

In general we bypass the bms for discharge. The bms is used for charging only in most diy boards. Discharge via BMS or Bypass BMS? [SRO]

Max motor amps are different from max battery amps. They are independently configured in your vesc based esc (stormcore). Battery amps occur at your batteries voltage. Motor amps occur at or below your batteries voltage (determined by your motors current rpm). It’s more complicated than that, but in general that’s why you can have higher motor amps than battery amps.

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Also read this Battery Amps, Motor Amps and Duty Cycle... Please Explain


If you’re going with a LLT, get the 20 amp 12s standard bms and bypass it, like Avi mentioned.

+1 for bypass

thanks guys, I’ve researched a lot in here but sometimes it’s easier just to ask the question, and get good links for reading!

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one last thing, can I get an app that works with iphones for it, I saw somewhere it’s only android compatible?

There are several ios and android apps.
I have not used the iOS ones, my guess is this one would be good GitHub - smagicld/xiaoxiangBMS: iOS app for Xiaoxang BMS. All the android apps are terrible.