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Simple Multi Cell Battery protection, 8 cell LiFePO4

Foreword:
Connect Cells in Series, with just a little bit difference in capacity, and discharge them leads in some problems,
the weak ones (least capacity) will be discharged first, and then pulled to zero and even all the way into reverse polarity,
depending on your systems low voltage cut of, if any att all.. many powersupply systems today handle a huge input voltage range
so killing cells is very easy. that is why this simply circuit come handy
It measures the voltage individually on each cell, when the first one is way below emply, it will turn off futher discharge.
There is a few mA idle current usage from this circuit, but the cells I use are 10Ah and the pack is in regular usage,
so it is not going to be drained measurable faster, you do the math 2mA versus 10000mAh capacity = no problem

Here is the schematic, it is easy to modify for any other cell voltage or even pack voltage
so it can be used for a number of higher voltage packs, use the idea and modify from here.
This circuit is fully tested and working.

Installed in mock-up mode, on the back side of my simple voltage indicator

Nice pack for a robot, all is offcourse home made

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Thomas Scherrer OZ2CPU 2019
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