No BMS . I use a big 600w balance charger and I just use cell monitors while I’m using the board
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You can’t really solder to the packs or I don’t recommend it. You need some “bus bar” clamps to hold the series together. I have other pictures of it on my thread. https://www.electric-skateboard.builders/t/ontario-canada-trampa-diy/100855?u=fallen
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Just be careful with the batteries because they have more than enough amps to instantly kill you or anything else that accidentally shorts them
Yes. They are GREAT CELLS!! I prefer the HP Headways 38120’s because no LIPO but Lipo4 and has that better chemistry with very similar specs…
These are on sale now for $4.5 a pop!
Probably best price/power ratio. Although not conventional cells
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I’ve seen these on youtube by jehu battery guy. He made an electric skateboard with it too. Wonder if a typical vesc can handle all that discharge current. Theoretically, I could just spend less than $50 and get good range. Crazy.
I also notice that on the website it said li-ion but on the video review they all said lipo. 
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I have run a single VESC 6.6 at 120 motor amps using one of these bad boys-https://www.amazon.com/gp/product/B073V2YJPT/ref=ppx_yo_dt_b_asin_title_o08_s00?ie=UTF8&psc=1. Even when it is hot outside, the VESC temperature has yet to exceed 45c. To control the motor temperature, you can install another fan on the side of the motor facing into the windings.
If you buy those 200a lipo cells, don’t forget to install lipo alarms and buy a good balancing charger because the voltage on the older cells will drop quicker than the newer cells.
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From what I read, typical bms will only balance charge when the cells are almost fully charge. So it makes sense to get a high quality balancer for these cells. I’ll stick with li-ion 
Most balance chargers will be able to measure internal impedance, so all you need to do is check each cell. I had access to a function generator and a bunch of other fancy tools so I properly measured all my cells impedance and just cherry picked the packs I built out of the spim08hp packs. Even the difference of 5mohms isn’t that bad ,may result in my one cell being at 3.2 when I cut it off compared to the others at 3.4-3.5 but when you consider the price for 42 of those cells compared to 2 store bought 6s lipos of similar size you can’t beat it. I will admit I’ve kill 2 single cells in my packs but that was more my fault than the batteries
My next battery though is going to be a 12s12p brick of 21700 Samsung 40ts. Will be roughly 2.4kw of energy. Just super expensive
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I want to see that pack. I’m sitting on a similar hoard of 40ts, not sure what to put them on. We could power a neighborhood in the meantime.
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Lol I like how we adopt new cells just as fast as the EV world adopts them. I’m interested in what could come next. Square cells?
Unless you plan a 4wd drawing 360a continuous amps discharge, I wouldn’t use those cells.
At 12p, you can afford to use cheaper lower continuous discharge cells.
Or similar cost cells with bigger than 4000mah capacity at a lower discharge rate.
You can probably look into those newer 26800 sized cells too.
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Yeah anyone have those on order yet? I found the 24/48 packs on AliExpress.
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That what who now?
US $218.00 | (48pcs/lot freight free)QB26800 NEW MODEL 26800 6800MAH MODEL AIRPLANE BATTERY CELL 3.7V 5C 30A EV BATTERY
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