I still believe the 12 bit adc is a major issue with Chargery current measurement. Chargery is redesigning the BMS and now using a 16bit adc.
Take a look at a popular current monitor IC. The
INA226 uses a 16 bit adc. The LSB step size is 2.5 uV. Using a 300A, 75 mV shunt, current granularity is 10 mA. That's a reasonable step size.
From my measurements (see chart), Chargery's current resolution appears to be 250 mA (with 300A, 75mV shunt). The difference between 16 bits and 12 is a factor of 16. If we scale the 10 mA resolution (with 16 bit adc) to a 12 bit unit then we should get 10 mA * 16 = 160 mA. So yeah, you're right. Chargery could have done a better job designing the current measurement. They could have gotten 160 mA.
Still, why settle for 160 mA (if correctly designed) when you could get 10 mA resolution?