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BQ34Z100-G1: Remaining capacity increase during relaxation

Part Number: BQ34Z100-G1

Hello team,

We are developing a 14S6P lithium-ion battery pack, BQ34Z100-G1 was used to estimate SOC of the pack. The mass production stage is close but we still get a problem that almost the same as in this thread https://e2e.ti.com/support/power-management/f/196/t/892256?tisearch=e2e-sitesearch&keymatch=BQ34Z100-G1

But instead of decreasing SOC as that thread, our problem is increasing SOC while pack is in relaxation, the current is zero, the pack voltage and the temperature do not change.

The DOD0PassedQ have negative value because of ghost current, whenever DOD0PassedQ decrease 1, the True RC will increase 1. The DOD0 cannot be updated (DOD0 Time do not reset to zero) when pack in relaxation mode, I known that it will cause SOC increase. Why DOD0 cannot be updated?

As I understand, DOD0 should be updated every hour when pack in relaxation mode. And when the DOD0 updated, the True RC should be re-corrected even if before that the ghost current cause it get incorrect value. am I right? 

The phenomenon seem disappeared when pack was run for 1 cycle. Why? 

Our production steps are as follow:

1) Program golden data-flash image file.

2) Calibrate 

3) Attach BMS into the cells

4) Send RESET command

5) Send IT Enable command

The increase SOC phenomenon seem never happen when we process attaching BMS into the cells before flashing the IC but because of production performance we cannot change the procedure.

During attaching BMS to the cells, power source to the BQ34Z100G1 is unstable. Is it cause the problem?

More information, we used two 0.5 mOhm resistors in parallel (0.25 mOhm equivalent) for current sensing. is it too small? 

Could you please help us?

Thank you in advance.