WHAT DOES THE NUMBER OF CYCLES MEAN?

The number of cycles refers to the number of charging and discharging cycles that a battery can undergo before its capacity decreases significantly. A charging cycle comprises a complete charging and discharging process, i.e. charging the battery from 0% to 100% and then discharging it back to 0%.

Meaning of the number of cycles

• Battery service life: The number of cycles is an indicator of the service life of a battery. The higher the number of cycles, the longer the battery will last before it needs to be replaced.
• Capacity loss: With each charging and discharging cycle, the battery loses some of its original capacity. This is a natural ageing process of the battery chemistry. After a certain number of cycles, the capacity can decrease to such an extent that the battery can no longer be used efficiently.
• Depending on the application: The number of cycles required depends on the application. For example, traction batteries in electric vehicles require a high number of cycles in order to function reliably for many years.

Example

A typical lithium-ion battery, for example, might have a cycle count of 500 to 1,000 cycles before its capacity drops to approximately 80% of its original capacity. After this number of charging cycles, the battery will still function but will no longer be able to store as much energy as it did at the beginning.

In practice, a battery's actual service life can be influenced by factors such as the depth of charge and discharge, temperature, charging speed and other conditions of use. Batteries that are regularly deeply discharged or exposed to extreme temperatures can lose capacity more quickly and thus have a lower number of cycles.