Cycle Life : Temperature vs. Charging/Discharging Rate Test

The life of a battery depends on 4 major factors. The battery can last up to 8 to 10 years if following is strictly followed.

  1. The temperature — Ideal temperature of battery pack should be maintained between 25℃ to 30℃ during charge and discharge cycle
  2. Charge and discharge current — it is measured as C rating. Ideal Charging current should be 0.2 C and discharge current at 1C (depends on quality of cell and cooling system if any)
  3. Depth of discharge (DOD) — DOD should be less than 80%
  4. Balancing of the cells — All the cells should be balanced. The difference between highest and lowest cells voltage should be ≤ 0.010 Volt

In this post we will see the effect of temperature and charge — discharge rate.


Test results achieved under following parameters

Temperature（℃）：45, 60

Parameter ：1C CC (constant current) & CV (constant volt) charging until 3.65V，cut-off at current till 0.05C， @1C CC. Discharging until 2.0V.

**Cycle life is defined as the no. of cycles obtained until the retention rate hits 80%.


Temperature Charge & Discharge Rate 3 cycles 50 cycles 100 cycles 150 cycles 200 cycles 50 cycles 100 cycles 150 cycles 200 cycles
45℃1C6031579456775588550396%94%93%91%
60℃1C5996562653084954458694%89%83%76%

Temperature of 45℃ and charge /Discharge rate of 1 C

There is a trend of 2% drop in retention for every 50 cycles after first 50 cycles. Estimated that there is totally 20% drop in retention after 500 cycles, which means retention is 80%. So that is the cycle life. This is continuously charging and discharging test in the lab(non-stop, no cooling for battery).

When it is charging and discharging with 8-12 hrs. which is halved of non-stop use and with on and off some idle time, We estimated cycle life will be about 750 cycle life.

Temperature of 45℃ and charge /Discharge rate of 0.5C

Estimated there is 1% drop in retention for every 50 cycles after first 50 cycles as discharging rate halved, and that there is totally 20% drop in retention after 1000 cycles, which means retention is 80%. So that is the cycle life. This is continuously charging and discharging test in the lab( non-stop, no cooling for battery).

When it is charging and discharging with 8-12 hrs which is halved of non-stop use and with on and off some idle time, We estimated cycle life will be up to 1500 cycle life.

Temperature of 60℃ and charge /Discharge rate of 1C

The retention rate already hit 80% level from the lab test, which is the cycle life of max 200 cycles by definition. This is continuously charging and discharging test in the lab( non-stop, no cooling for battery).

When it is charging and discharging with 8-12 hrs which is halved of non-stop use and with on and off some idle time, we estimated cycle life will be up to 300-350 cycle life. At this such high temperature, cycle life may improve but limited.

Temperature of 60℃ and charge /Discharge rate of 0.5C

Estimated it hits 80% level at 300 cycles although discharging rate halved but temperature is high. This is continuously charging and discharging test in the lab( non-stop, no cooling for battery).

When it is charging and discharging with 8-12 hrs which is halved of non-stop use and with on and off some idle time, we estimated cycle life will be up to 400-450 cycle life. At this such high temperature, cycle life may improve but limited.