Dual 500W Hub Motors + DIY Battery/BMS + ESC Malfunction (Video)

In this 1 minute video you’ll see my issue. Do you know what’s going on here? Why is the board turning off when a load is applied? Why can’t it turn back on unless I plug it in for a second to reset it?

Is my BMS too weak for my Duel 500w Hub Motors?


At 30V (dead) you’d pull 33A to power dual 500W motors so if it’s a 20A BMS you’re easily popping it. Odds you actually get 1kW from that is basically zero but still you can easily exceed the BMSs rating. Get the appropriate BMS (aim for 40A or so) or bypass your existing one (connect the ESC negative directly to battery negative, remove the P- connection)

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If I was as smart as you when I was a kid, you all would work for me now. But nooooo. :rofl:


Thank you so much for your feedback, ZachTetra! I can’t thank you enough for your insight. I went ahead and ordered this BMS to replace the one I have now.


My instincts are saying that my battery might not have enough cells in parallel either? Do you think my 10s2p battery is enough to run these motors? I could attempt a 10s3p but I may have to rethink my enclosure quite a bit. I would love a tip on where to buy rugged enclosures if you have any resources there. Thanks, bro!

Honestly I don’t really trust those cheap BMSs, I would just use them to charge and balance the pack but pull current straight from the battery to the ESC (it’s called bypassing).

Those cells are only rated for 10A a piece so you can pull 20A max but the pack will get hot and have far less performance than you would expect. Honestly you should have done a longer planning stage, maybe asked the forum before you comitted to those parts.

If you use a 10s2p then I am very fond of the Meepo V3 enclosure for batteries and ESCs, it’s only $50 shipped and they are very nice, but you already seem to be hurting for length so maybe not that. You can always try to find a waterproof case like a Pelican or something, but you will be limited on height and might need some risers to have sufficient clearance

Fascinating! I’m committed to using a BMS because this is for an 8 year old.

So, I buy them both? How do I find out the size of the interior? Will my 10s2p battery fit? 3p? How deep is the battery enclosure! Thanks again, ZachTetra!

That is up to you, I used to have a 10s1p and single ESC in just the battery enclosure but I don’t think there is more room than that. Meepo sells a 10s2p 40T battery that fits in the enclosure, and they list the battery size, you can easily fit a 10s2p 18650 if it’s built right, I have seen someone fit a 10s4p 18650 but it requires a lot of material removal and a gasket, so 10s3p might be possible without a gasket (will need to remove all the internal structure though, it’s still strong but not rectangular is all)

The ESC will limit power and cut out at low voltage on its own, there is no need to have the shut down feature in the BMS. In the event something happens it’s better to have the battery functional so you can slow down, if the BMS cuts out from max regen current on a hill he will not be able to stop. Honestly he doesn’t even need a dual motor, if you run single motor it would be a lot easier, he can work up to a nice dual board in a couple years

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