So if i will have a setup like 10S4P based on SAMSUNG INR18650-25R, 2500 mph (decelerated 20A) i need to buy 80A BMS? When it’s like 10S3P = 60A? What about series number, if BMS will be dedicated for 12s, it’s still fine to use it with 10s?
the series number HAS to match the battery you are building but the max amp dis charge does not have to match your max discharge and would be better if it was lower. so you could use a 60A bms on a 10s4p set up no problem but not a 10s4p set up on a 12s bms.
I’m thinking of repacking/rebuilding a Yuneec 7s3p battery to hold 10s2p. Who can I trust to tab my battery?
I’m also looking for advice on 10s BMS. I might just do it myself because the Yuneec battery pack is tight on space.
@delta_19 A fair few BMS’ allow you to setup a battery with a lower cell count than what it is rated for
I’m making a 10S2P battery and have one 36V 10S BMS that can handle 80A discharge. How would I go about wiring the bms to the 20 cells? I’m trying to keep the battery as flat as possible.
You have to write your balance connectors to each pack of series.
Check this for more details. http://www.electric-skateboard.builders/t/connecting-a-bms-quick-guide-how-to/6122
You shouldn’t plan on an 80A discharge current on 2p if you’re running 18650 cells. 18650’s normally output about 20 per cell (40a in 2p) but you should really plan on using it for 10a per cell.
I’d recommend adding another 1 or 2 parallel groups in your pack. Even with a higher discharge pack you’ll probably need a 60A BMS at most, or just bypass the BMS for discharge.
will using the 80A BMS have a negative effect on the cells? I thought that getting a bms that can handle more than the 18650 cells output is fine.
There was a very helpful diagram on that thread, thank you 
it’s fine but why spend the extra money and space? if you want a smaller pack getting a lower discharge bms will save space as well
I’m planning to add 2 more 10S packs later, just planning for the future.
you’ll most likely be fine with a 60A bms don’t think you’ll need 80.
Bigger packs last much longer. I would recommend at least 3 parallel. Street boards won’t pull more the 30A from what I have read so 80A is way over kill. Usually people only pull 5 amps when riding.
well then, I’ll downgrade when I can.
This may interest you:
If you already purchase the 80A bms just use it. Overkill is not bad or anything if anything its a good thing cause things then run cool. Heat is wasted energy and just damages things. Also I do not get the BMS paragon is selling. It is only rated for 20A continuous. For e-skate 40 amp is the bare minimum. 60A will work for everything and 80A also would work just as well if not better.
I would feel bad if you got a new BMS even though it would work perfectly fine.
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Yea if you already have a bms it’s no problem. Just know you can go smaller and be fine. Paragon’s bms is a good choice too if you bypass it for discharging.
yeah, I already have the 80A bms, it’s 2 times the size of a normal one but that shouldn’t be too big of a problem because my deck can accommodate it.
Great! Again there is no need to downgrade to 60A unless you want something a little smaller. Overspecing your board will make it last longer in the end
Just wondering if anyone knows the BMS’s charging procedure when charging these li-ion cells. For example can it regulate the inputted voltage and amperage so that you’re not frying your battery, and does it balance each cell while charging like a normal hobby battery charger would? BMS’s seem very convenient but if they’re charging the battery in an incorrect manner I wouldn’t want to use one.