but its pretty. and eliminates stabby bits. and god dammit it it brings me joy in this terrible world.
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Does that BMS have cell balancing? Which model is that? It looks nice and smallā¦
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Been looking into something like this for my thesis. Iāve found something thatās a bit pricey but I think worth it.
Itās charge only, discharge bypassed
But does it have balancing?
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so doesnāt balanceā¦
shame
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I hired Damon because I know Jack about building batteries and didnāt want to blow up a board Iāve got so much invested in. Especially since there are so many unobtainum parts on the build. Iāll blow up my trampa for a third or fourth time (donāt remember if Iāve blown it up 2 or 3 times already) learning batteries. When he asked what bms I wanted I told him to pick what he thought would be best.
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It might balance, but I have seen others looking like that having no balancing capabilities. Without knowing exactly which BMS it is, and/or having high-res images of both sides, itās hard to say. I donāt see a row of balance resistors on it from this angle, thatās why I asked. This has gotten me in the past.
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If it has balancing, itās on the other side
LoL just wait for Damon to chime in
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Looks too small to balance
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āit will keep your pack balanced because i pre-balanced your cellsā
this literally doesnāt mean anything 
a bms with no balancing will NOT keep a pack balanced.
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Jst have a life of ~20 connections even the Wurth ones
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It balances at the top end of the charge cycle. I think this debate started because of the lack of info on the product page for these.
Discharge protection bypass has zero to do with balancing.
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Actually it does. BMSs with ACTIVE balancing can bring a pack back from gross imbalance. BMSs like these will MAINTAIN balance by doing their thing at the top of the charge cycle if you leave it plugged in until the charger is green. So if you balance the pack first it will stay balanced.
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BMS with active balancing will keep a battery whose parallel groups have mismatched capacities balanced even during use, granted it can keep up with the load.
Active balancing means moving energy around through flyback or full bridge converters.
We donāt see it anywhere except maybe EV because of the sheer size and cost of said DC-DC converters and floating MOSFET and gate drive array.
Basically all the BMS here are that crappy passive balancing that basically just bleeds off current from the highest voltage cells and basically tries to bottom balance the pack constantly. It just burns off the power.
The only thing those are useful for is MONITORING that is, cutting off the output to protect the cells from overcharge or undercharge.
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Active balancers have nothing to do with the discussion here.
A BMS is either balancing or non-balancing (just cuts off charging when first p-group hits ~4.25v).
WTF is āMAINTAIN balanceā? Is it able to balance or not?
Saying the pack will stay balanced BECAUSE you āpre-balancedā (lol) it implies it does not actually balance at the top of the charge cycle?
Youāre reading a fragment of a conversation that probably shouldnāt have been posted to begin with.
They do keep a pack balanced provided the pack is built out of pre-balanced p-groups. After i build my p-groups i balance charge them on a rig i built then weld / wire them into a pack.
What they will not do is fix a pack thatās wildly out of balance. But if a pack goes wildly out of balance, it needs to be repaired or replaced anyway. Chances are there are some bad cells or something else is wrong.
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