Effects of Discharge Cut-off Voltage Level on Available Battery Charge Capacity and Battery Life

The capacity of lithium-ion batteries decreases after each cycle. This decrease varies depending on the chemical structure of the battery, the magnitude of the current drawn from the battery, and the depth of discharge. To prevent deep discharge damages, the discharge cut-off voltage level is provided by the manufacturer. Exceeding this critical voltage level will decrease the discharge capacity of the battery. Therefore, to prevent damage to the battery, the battery voltage is continuously monitored during discharge processes, and operation at a voltage below this critical discharge cut-off voltage level is prevented. Conversely, if desired, drawing current from the battery can be stopped at voltage levels greater than the discharge cut-off voltage level determined by the manufacturer. However, in this case, the battery's full charge capacity cannot be utilized. Consequently, the preferred discharge cut-off voltage level will either affect the battery's lifespan or result in less utilization of the battery capacity in each cycle. This article presents a study investigating how the discharge cut-off voltage level affects the battery charge capacity. The study examines the available charge capacity and the decrease in charge capacity according to the cut-off voltage.