Wanted: Active 16S LiFePO4 cell balancer

Looking for the above. Or 2x 8S would do. Passive balancer would do OK too.
Based in Jhb.

What voltage do LiFePO4 balancers operate at?

On some OEM BMSs you can set the voltage and that is a full topic for discussion on its own ! e.g. do you balance lower than your cell charge voltage or below it ?
In my case I am trying to balance at 3.5V but the desired charge voltage per cell is 3.6V. This is only whilst I try to get all the cells top-balanced. The cells are from 2x scrapped Pylontechs. so it is not easy as with prismatics to get to the cells themselves to put them in parallel to top balance them. The voltages on the pack are a bit too uneven and hence why the balancer (albeit at a very low current) would try to discharge the cells which reach the balance voltage first and thus give the ones with lower voltage to catch up. Yes not very efficient but is effective.

Indeed! Paralleling cells is for the hobbyist. You can’t really do this with the number of cells you are dealing with…
Does the active balancer feed current into the cells to adjust their voltage? (as opposed to the discharge only version)
Couldn’t you salvage the BMS from the Pylontechs as well??
How about this one: 8S 24V 60A BMS | Centurion | Gumtree South Africa

Rich, the active balancer takes power from the cell/s that the voltage is higher than the rest and feeds its power to the lower voltage cells. Neat and energy efficient ! The passive one is dumb and only discharges the cells that have reached the threshold voltage.
The reason I was given the 2x Pylontechs is that they had been struck by lightning and the BMSs were both kaput. The forum member who kindly gave them to me had his insurance company replace the 2x Pylons. Thanks for the link for the BMS from LBSA. I aleady do have a 16S which I use and with the interface to the laptop app I can monitor the voltage on each cell. It is this unit - https://lithiumbatteriessa.co.za/collections/bms/products/lbsa-100-15s-16s-48v-lifepo4-smart-bms-with-display-and-bluetooth-functionality. The BMS does have a balancing function but the power that it can dissipate is really too small - I read it is approx 66 mA discharge current - way too small. I have seen other members of this forum use a bulb (I am using a 50W halogen) across a cell to lower the voltage and this does work. I hooked up a timer that discharges a connected cell for a selectable period. This is to prevent me forgetting that a cell is being discharged and possibley damaging it !

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Hello,

Would something like this work…

I got these to help my Daly BMS - never used. Since then, have acquired a JK BMS with 2A balance so happy to pass on… Let me know if you interested

Cheers

Thanks - will PM.