Battery is done, it was a lot of work… now the question is : should i use it for discharge or charge only? I don’t want it to fail like it happened before on my eskate…
Most guys used BMS only for charge. If you asking about BMS.
I use it for charge AND discharge and work very well. By my side, I have work 8 years on battery and it’s a lot safer!
If it has a high amp rating then you can use it on discharge too! Id slap an aluminum heatsink on it to keep it cool when riding hard. I’ve been using mine to charge and discharge without any issues so far (24s 150a Smart BMS).
Thanks for your answers. Yes it’s high amp rating (320A) so i can use it without any problem. What are the risks of not using a BMS for discharge ? i guess it’s to avoid over discharge on the cells but if i properly set the minimum voltage on my VESC is it not enough ? I have 12S so i will set my VESC to cut at 36V (3V per cell)
Been using vesc without bms for 1 year without issue with (safe) good settings. But now i am using 150A rated bms for 6 months and i am very happy With it, managing balancing and settings with bluetooth is a must have ( also can set temp cutoff and so on)
I even did 1hour and half rides without issues. Never had to test the overcurrent function hopefully 
Hi. Some news of my build :
I finished the battery with integrated BMS and then I realized something strange : you can turn on the BMS but there is no way to turn it off. If you want to turn it off, you need to do it in the Bluetooth app, and turning off will also reset to factory settings. So if you don’t turn it off, the BMS stays in “stand by” mode, and i’m not really confident about it. I don’t want to risk a BMS failure when the battery is in the house or in my van so i decided to remove the BMS. I will use 2 voltage controller instead (with alarm) when riding.
When i removed the BMS i realized that my cable connections were not great. That’s how i did it first, with double 10AWG cables :
I want to do it better.I still have some 6AWG and a roll of flat copper wire. I had a little test to solder them together :
I tried to pull as hard as i can and it looks like the soldering is strong enough.
My plan is then to solder the copper band on all the battery lenght like this :
I need advice from the battery experts on this forum. Do you think it’s a nice and safe way to do it ?
Thanks
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Few weeks ago were similar discussion about BMS and someone proposed to use some on/off switch.
Check this thread for example
and this thread also:
From what i’ve seen in datasheets the braided copper sleeves have really low copper area - it’s basicly 40 somewhat very thin wires and a million crossings.
Therefore I think your 2xawg10 is probably higher area. You should check this.
Also your connections will not be 100% balanced due to the voltage drop from first to last parallell group on the connection line. If you don’t run super high battery currents like +300A i’d not worry about this though.