Getting a battery pack built for me. Need a few questions answered

ESK8 Electronics
#1

So I bought 40 18650 Samsung cells. I was told 10s4p would be the best configuration for my single motor build. I have the Enertion R-SPEC 6372 motor.

Because I don’t have any knowledge or a workplace or even the tools to put a pack together, I’m getting someone I know to do it for me. He said he would help but he asked me a few things…

"I see you have no pack protection circuit, I’d strongly suggest we include this rather than run the risk of your pack going the way of low priced hover boards.

Do you know the maximum current you expect to draw from your motor? This will help us decide on the nickel strip we use for welding as well as an appropriate battery protection circuit.

We can also help with a charger."

Before I reply to him I’d like to know what a pack protection circuit is? And about the maximum current, what does that imply? Thank you in advance.

#2

He’s talking about a BMS pretty much. It helps prevent damage to your cells by managing discharge/charge currents and prevents voltages from getting too high or low. You should be good with a 60-80A max current BMS depending on your weight, terrain, and gearing reduction. For reference the VESC, if you’re using it, handles 50A continuous (240A burst).

#3

Oh thought he was talking about a Bms, just didn’t call it that haha. So I should say I want a 60-80 Max current or?

#4

Sounds like your friend knows what he’s doing. You want a BMS (battery management system) 60-80 amp continuous current capability. you will have to order it from China or get it on eBay. If you get one on eBay, get it from seller called Supower. They have quality. At 10s you probably won’t pull over 30amps from the battery. But its a good idea to over build.

#5

Sweet. So I’ve replied to him, see what he says next. When he asked what Max current I want, 30 should be right yes?

#6

60-80 like we said :stuck_out_tongue: You could probably get away with lower, but there’s a chance your system will shut off if you ride the motor hard.

#7

Max current could mean peak current. You should think in terms of continuous current. The cells your using should be 20amp continuous X 4p so the battery pack will handle 80 amp continuous You can use a 60 amp continuous BMS How heavy nickel strip you use depends on the capability of his welder

#8

Thanks! And thanks to @Jinra too! I’ll let you guys know how it all turns out . I have everything, my motor is en route to my place, the VESC is at the post office and I just ordered an enclosure from @MasterCho so things are finally arriving!