Question:
How to get accurate voltage of the battery up to 1mV?
Answer:
Using VFOCV to measure the voltage is more accurate. The VFOCV can reach the real value of the voltage more quickly if set RCOMP0=0x0000. It needs about several minutes if the initial value of VFOCV is not quite far from the real value. If the VFOCV is too far from the real voltage, software reset the IC first.