I'm having issues finding the bad cell(s).
Here is a video:
I load the battery pack and monitor two cell groups. The bad cell group 11 (which is actually group 3) and some random one.
It is very clear that cell group 3 (11) is going out of balance when loaded.
I harvested the cells and did a capacity test on all with my liitokala Lii-500s but couldn't notice something obvious.
I did discover one thing but could it be that cell?`
My Lii-500s can display the charge and discharge capacity:
Cell 1: Discharge: 2872 ; Charge: 2832
Cell 2: Discharge: 2890 ; Charge: 2741
Cell 3: Discharge: 2830 ; Charge: 2836
Cell 4: Discharge: 2903 ; Charge: 2910
Cell 5: Discharge: 2781 ; Charge: 2858
Cell 6: Discharge: 2695 ; Charge: 2955
Could it by any chance be an issue with cell 6?
Edit: I measured Cell 6, 3.2V, put it in the charger and set it to discharge at 500mA and it dropped very quickly (less than a minut) to 3.02v. After three minutes down to 2.9v. Took it out, measured about 3.05v, after 30 minutes, 3.15v.