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Making battery balancer?

Who knows electronics?

I’ve got 48 lg hg2 cells for a 12s4p pack and want to omit the bms. They are the safest li-ion chemistry and don’t even have a gas release valve and my pack will be big enough I won’t be fully charging it.

Anyway I plan to have both sides of the 4p accessible so I can monitor and balance by discharging. I’ve seen this but it’s just for monitoring:

With my simple understanding of ohms law I feel I could reduce the circuit resistance and that will incrwse the current …thereby discharging any high voltage cells in the pack. No?

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Why not get a smart BMS, which stops at 4.15 and balance cell’s there. And bypass discharge?

I want to keep it simple and feel this pack is big enough and the cells safe enough to do it this way. …no more room on the deck

Just increasing current draw will only cause the lower voltage cells to discharge more current, and that will cause issues potentially damaging your battery pack. Unless you get a 12 cell balance charger your going to need a BMS. I highly recommend a bms as it allows just plugging in a single connector and you don’t have to worry about balancing the cells.

Now I bulk charge 12s and balance through the addition of battery medic-like devices connected to the balance leads. I like it because I can keep all my batteries connected in series on the board and use one plug to charge. I want to do the same with this li-ion pack but make the dischargers/monitors that I will attach to the 4 cells in parallel

I want to increase current draw from the 4p to balance

It would work… As long as you don’t over charge or discharge too crazy then the parallels would stay pretty much where they are I would check them once every hundred miles and manually balance them every so often.

Like I said it would work but it’s not ideal but I’ve seen it done before on E bikes

I don’t know people act like batteries are so sensitive. When you charge the pack just make sure to charge at a pretty low amp rating… Like 1-2 at most

I’m trying to find if I can change the circuitry and maybe Idecrease some of the resistance on a voltmeter so I can connect across the 4,get the voltage, and be discharging at once