What Constitutes A Life Cycle for Lithium Batteries?

Cycle life or life cycle is defined as the number of cycles (with a 100% DOD) a cell can perform before its capacity drops to 80% of its initial specified capacity and then starts to reduce visibly its performance.

The cycle life of batteries is the number of charge and discharge cycles that a battery can complete before losing performance. The cycle life of Li-ion batteries is affected significantly by the depth of discharge. 

The depth of discharge is the amount of a battery’s storage capacity that is utilized. For example, a battery that is discharged only by 20% of its full energy capacity has a much greater cycle life than a battery that is discharged more deeply by 80% of its capacity so that only 20% of its full energy charge remains. 

Which is why we recommend 20% SOC discharge on all Hubble Lithium batteries and 100% SOC recharge to reach bottom and top balance. The cycle life is given in a number of cycles. Factors influencing cycle life are the average state-of-charge (SoC), the range of SoC during the cycles, and the depth of discharge when starting with a fully charged battery. 1 Cycle would be full to flat and back up to full again.