Factors affecting battery life

Ambient temperature has greater impact on the battery. Over-high ambient temperature can cause battery to overcharge and generate gas, and over-low ambient temperature can cause undercharge of battery, both of which can affect the battery life. Therefore, the ambient temperature is generally required to be about 25°C, and the UPS floating charge voltage value is also set according to this temperature. In practical applications, battery is generally charged in the range of 5°C~35°C. Temperatures below 5°C or above 35°C will greatly reduce the battery capacity and shorten the battery life.

The impact of discharge depth on battery life is also significant. The greater the battery discharge depth, the smaller the number of cycles of use. Therefore, deep discharge should be avoided during use. Although the UPS has a battery low-potential protection function, when a single cell is discharged to about 10.5V, the UPS will automatically shut down. However, deep discharge of the battery may also occur if the UPS is under light-load discharge or no-load discharge.

During storage, transportation, and installation, the battery will lose some capacity due to self-discharge. Therefore, before being put into use after installation, the remaining capacity of battery should be judged according to open circuit voltage of the battery, and then the battery should be replenished by charging in different ways. Spare batteries should be recharged every 3 months. Quality of battery can be judged by measuring open circuit voltage of battery. Taking a 12V battery as an example, if the open circuit voltage is higher than 12.5V, it means that the stored power of battery is at least 80%. If the open circuit voltage is lower than 12.5V, the battery should be recharged immediately. If the open circuit voltage is lower than 12V, it means that the stored power of battery is less than 20% and the battery is unserviceable.

The battery charge and discharge current is generally expressed as C, and the actual value of C is related to the battery capacity. For example, for a 100AH battery, C=100A. The optimum charging current of Xiendi lead-acid maintenance-free battery is about 0.1C, and the charging current cannot be greater than 0.3C. Excessive or low charging current will affect battery life. The discharge current is generally required to be between 0.05C and 3C. UPS can meet such requirement in normal use, but accidental circumstances should also be prevented such as battery short circuits.