How to Calculate the LiFePO4 Battery Cycle Life?

There is no accurate way of calculating the exact LiFePO4 cycle life. This is because of the several factors that cycle life depends on. However, you can get an idea of cycle life by calculating the battery runtime.

To calculate the runtime, you need to find the watt hours of the battery. This is done by multiplying the Ampere hour capacity of the battery with its rated voltage.

For instance, for a 100 Ah battery rated at 12V,

Watt hours = Rated Voltage x Amp hour capacity

Watt hours = 100x 12 = 1200 Wh

This value is then multiplied by the battery’s Depth of Discharge. Considering a depth of discharge of 80%,

Usable Watt hours = DoD x Wh

Usable Watt hours = 0.8 x 1200 = 960 Wh

To calculate battery runtime, you can divide the usable Wh with the applied load. Therefore, if you want to find the runtime when running a TV of 100 Watts,

Runtime = Usable Watt hours / Applied Load in Watts

Runtime = 960 Wh / 10 W = 9.6 hours