Home        Store        Learn        Blog

Know Li-ion battery Capacity

Hi ,
Can anyone help me to know the backup capacity of Lithium-ion battery by discharging process using balance charger?


Hi @sudheeshk ,

I’m not sure I understand your question, can you please restate it? What do you mean by “backup capacity”?


I believe he is trying to know the capacity of each battery. Generally as we do multiple charge - discharge cycles then the endurance of operations reduces as battery capacity reduces. Wanted to know standard methods to benchmark all the batteries to plan replacements etc…

Hi @sudheeshk and @kappa,

I see, understood. To determine the present capacity of the battery versus the original rated capacity, you should use the same method that Samsung uses to rate the cells. As far as I can gather from the datasheet, the method they use to rate the cells at 3000 mAh is as follows:

  • Charge to 4.20 +/-0.05 v @ 0.5C with a 100mA cutoff (CC-CV)
  • Discharge to 2.50 v @ 0.2C
  • Execute test at 23°C

Note that the ambient temperature and charge/discharge rate during the test can have a significant impact on the result, so the above method should be used for a totally accurate comparison.

There are some good graphs showing cycle life and how discharge rate affects usable capacity of the cells in the datasheet.


Thanks for your reply Adam.Can we do this test using Blue robotics Battery Charger/discharger ?