Customizing cell chemistries: range of values for adjustable parameters

Hi! Very cool project here. I know your BMS’s are designed for Li-ion chemistries, and are customizable by adjusting settings in firmware.

I am doing some research into next-generation water-based batteries (closer to lead-acid in terms of tech, than to Li-ion). Some of these chemistries, while potentially cheaper/more sustainable/longer-lasting than lead-acid or Li-ion, also require a BMS to prevent overcharge (less for safety, more for preventing degradation.)

My question is what is the range of adjustable parameters to modify cell chemistries in the BMS C1? Say, for example had a 1.3 V battery. Could we have a 16s pack with a cell HVC of 1.3 and pack voltage of 16*1.3=20.8 V? LVC would also be adjusted accordingly.

I know a different board design may be optimal for such lower cell voltages, but I’m curious if the BMS C1 could be a starting point for experimenting with lower-voltage, emerging water-based chemistries. Thanks!

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In principle that should be possible. The only limitation could be the bq76952 chip.

I’ve just had a look at the reference manual. The chip’s lowest protection voltage threshold is 1.012 V (both for undervoltage and overvoltage). If that’s low enough, I think it should work for your application.

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Thanks for the informative reply, I also had a look at the datasheet and if we can disable the undervoltage protection, I think it may work. From the datasheet:

The BQ76952 device integrates Cell Undervoltage Protection (CUV), monitoring the voltage of every cell
using a comparator-based circuit, and triggering a CUV alert or fault when a cell voltage falls below the
CUV threshold. The CUV threshold is programmable from 1.012 V to 4.048 V in 50.6 mV steps and is
set by the Protections:CUV:Threshold configuration register. The CUV protection is enabled using the
Settings:Protection:Enabled Protections A:[CUV] configuration bit