No Name | Custom Deck | Caliber M Trucks | Undecided | Undecided | 36 Volt Battery | VESC

ESK8 Builds
1

Hi everyone, I am currently building a battery using Molicel P42A cells in 10s2p configuration. Below are the specs for these cells:

  • Size: 21700
  • Style: Flat Top
  • Nominal Capacity: 4200mAh
  • Continuous Discharge Rating: 45A
  • Nominal Voltage: 3.6v

MY CONCERN: I am unsure what kind of BMS and VESC to use, and I don’t know exactly what to look for when researching them.

Here is what I have found so far for the VESC: https://a.co/d/1qWxKdK

Here is what I have found for the BMS:
https://a.co/d/dcKsYq2

This is a second BMS I was also considering:

If these two items that I selected would end in something disastrous, please advise me with the correct information and I greatly appreciate your help, thank you.

2

The most concerning thing to me, is everything you didn’t ask. Skate batteries are not easy or straightforward to build safely and there is a lot of outdated information online. Making batteries for skateboards is extremely dangerous.

How do you plan to make the P-packs? would be my first question. Where is your instruction coming from? How old is it? Does it involve soldering cells? Is it limited to YouTube?

VESC 4.12 is really outdated, but would work at 10S

That no-name Amazon BMS I would not use

That MBoards BMS is just a rebranded Daly BMS. Ask what the balance current is. Also, it says Sold Out. Never plan a build around using unobtainium. Daly 10S BMS are available on AliExpress though.

If you’re not given a balance current, assume a BMS doesn’t balance, and DON’T GET IT.

I would stick to Daly if you plan to use a “dumb” BMS.

4

You have some valid concerns. I assure you I know what I’m doing as far as assembly goes.

I spoke previously to a support member at Mboards who notified me they have the BMS linked in stock, and that they just haven’t updated their website.

I found the BMS the Mboards clone is made from, and the balancing current is 30 +/- 5 mA.

5

You should still ask them and have them tell you, even if you think you know. Many BMS look identical but have different layouts & settings. Plus, you want it written so if it doesn’t balance, then at that point it’s defective, because you asked, and didn’t assume.