LiFePO Balancing

233

02:27:17

The idea is to shunt some current around a LiFePO cell once it is charged to 3.3V. The shunt starts to let current flow at 3.3V and increases up to 75mA at 3.65V when the cell should stop charging. This will also serve to release over charge which can happen as the battery cools off.

LiFePO info:
http://www.powerstream.com/LLLF.htm

TLVH431 Equivalent circuit includes: op-amp, 1.24V ref, and NPN. 

Balancing will cause all the cells to be full charged at about the same time. During discharge the smallest capacity cell will trip the disconnect since its voltage will drop first, and will also determine the overall battery capacity.

Self-discharge is almost non-existent in LiFePO4, but this will have 80uA

published 11 years ago

flowDAQ

11 years ago

This was set for LiPO but now it is LiFePO

flowDAQ

10 years ago

update so it works over range 3.33 to 3.65V

necasworld

10 years ago

I cant open this on my tablet

flowDAQ

10 years ago

Haha, I find it hilarious that anyone would think I care about such a problem.

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