How to judge backward battery

When the battery floats, how to judge the backward battery? Generally, the terminal voltage of the backward battery is low at the time of discharge, so the backward battery should be measured in the discharge state. If the terminal voltage is the lowest in the three consecutive discharge cycles, it can be classified as the backward battery in this group. If there is a laggard battery, the battery pack should be recharged equitably. For example, if the floating charge voltage is less than 2.16 v, it should be taken seriously.