In my experience I’d say yes, but an expert on the matter may say otherwise…
My opinion is that it is worth having a large high amp output bms in order to have over discharge cell level protection along with short circuit protection. Plus the bms will protect against over charging while regen braking.
This is pretty defeating. Been waiting a few weeks and my $60 Bestech is dead the same day I install it.
I still think something else is wrong. The Bestech are factory tested before they ship it. I have never got one DOA.
I’ve got working bms if u want one
Please pm me details!!
I thought I sent u one
I tried searching around, but didn’t find anything. What’s the preferred way to bypass the BMS for discharging? The main reason I want a BMS is so I can put just one plug on my enclosure and the BMS takes care of balancing the cells as they are charged. I don’t really care about over current or them being balanced on the fly or while riding…
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Stay tuned… I am doing a 12s4p build which is almost complete… No BMS. Yet I will have balance charging. I will be placing (2) 6s balance leads, one on the first set of 6 x 4p packs and another on the second set of 4p packs. There will be a single xt 60 or 90 plug for the entire 12s4p pack that will serve as the charge port. That circuit will connect to an antispark as well by splitting the +/- but that is a small detail.
The big deal will be No BMS. I bought a 12s (truly 12s charger) + a server power supply that can deliver 75A to the 12S charger off of ebay.
Here is a preview for now of the 12S charger/port:
Charger:
Charger plugin 12S card:
It really wasn’t more expensive than a 12S 48V 60A BMS + dedicated laptop style brick which will cost you $120-$165 based on your shipping options.
It’s a one time investment. The only downside is… if I sell the board, the other guy will need to have a 12S charger too. But I don’t intend to sell the board 
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I’m a sucker for prebuilt packs… No assembly from me = less chance of a problem for me
Edit: dang I love it when I fill the whole front page with my name 
ok so Im using a 10 4p battery but I can’t afford to buy a 80 a bms would a 40a 10s bus work for charging my battery safely.
The esc that I’m using controls my battery discharge
If you’re gonna use the BMS only for charging, you’re safe. A low amperage means that the charge will take more time.
I do have a question too regarding BMS. Is it okay to buy a 10S BMS for a < 10S battery ? Just not plug the last wires and that’s it ?
I’ve been using my Vanguard battery with bms only for charging, I don’t have any safety feature enabled by doing this, so I wouldn’t suggest people do it unless, like me, you know exactly when your batteries are drifting and immediately take measures to fix the issue.
This is the procedure I use to check battery status:
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Check the SOC at the end of my daily commute, if it’s 71% as soon as I arrive and goes up to 74% before o plug it to the charger, battery is good and balanced.
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Check the SOC everyday as soon as I unplugged from the charger, it must be 100%, if it’s lower battery drifting is happening
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Charge my battery everyday with a lab power supply at 41.5V on my 10S4P and see if the current is drops at 0.02A at end of charge, if it still outputs 0.3A or higher for more than 30 minutes, one cell or a full pack is bad.
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Open the enclosure once a month a measured each pack looking for drifting, check for broken connecting wires, or crooked balancing wires, write down the differences in an excel sheet.
If don’t want to go through all this hassle just use bms for charging and discharging and let it do its job.
For me I like doing this and enjoy it very much.
Im not an expert on this topic but in a video I watched the guy said that that would not work and you need to get the bms for the right voltage of your battery even if its just charging
Im using a esc that discharges dual 35 a continues per motor and I have two 32a rated motors will this cuase problems with over heating or just kill my motors
Was your board that caught on fire also bypassing the BMS?
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Yeah that makes sense. Thanks
Im using a esc that discharges dual 35 a continues per motor and I have two 32a rated motors will this cuase problems with over heating or just kill my motors
Yes, it was determined the cause of fire was a loose bullet conector making sparks on a neoprene rubber.
I wonder how would a BMS prevent a fire on this case
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