BMS wireing charge/discharge

Hi there. Hope you folks Can help me. I have Got ny hands on a bms and Would only use it to charge, not discharge. My bms does NOT have a P-… is that Strange? Can i do it This Way?

Just connect the Battery - to the VESC Directly instead going through the BMS. This will discharge directly. the C- will only connect to the Charger. But your Regen charging will then also bypass the BMS.

I would stay safe and keep the BMS connected. Is 45A not enough for your setup ?

Thanx for speedy reply! I have 10s2p Li-on 18650 batterypack. I use a vesc. I have some concerns about the 45A when regenerativ-Breaking. That is why i was thinking about leave the bms out when discharge, and only use it for charging. Think it would work??

No, there are different kinds of BMS,

  1. charge and discharge different port (C- = charge, P- = discharge)
  2. charge and discharge same port (in your case C- = charge and discharge)

Do you have specs for the BMS, or what’s the dimensions? Maybe you can use it for discharge, too.

No reason to worry


Here is the bms that i have.

Looks good, I would use it for discharge, too. It would shut off at 130A (±10A) which is more than you will ever discharge, especially with 2p. But you limit that in the settings anyway. Also you have to limit the batt regen to 4-5A ech vesc because of 2p. No way you will ever reach 45A.

Connect Battery (-) to BMS B- Connect Battery (+) to charge port (+) and use it for positive discharge Connect BMS C- to charge port (-) and use it for negative discharge

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Think you so much!!

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It seems to be Working fine! Thanks again! Just a quick question…: I have a 12v charger… Can i use it, or will it fry?

Do you mean 12V input or output voltage? For 10s you need a 42V Li-ion charger.

Og sorry. Of course output. I order one strait away Thank again