The battery of an uninterruptible power supply (UPS) provides the backup power to critical devices whenever the main source of power goes out. This makes the battery one of the most important components of a UPS.
When a UPS battery is stored, it normally discharges at a rate of between 3% and 10% per month depending on the rating of the battery and the temperature of the place where it is stored. When the surrounding temperature is 25°C, the discharge rate is at 3% per month. This increases to 10% per month when the temperature of the storage area is at or more than 30°C.
It is essential to recharge a UPS battery within six months. However, if the ambient temperature is more than 30°C, it is necessary to recharge the UPS battery every three months.
This is indispensable since large crystals or heavy lead sulfate may form on the battery plates if the UPS battery is left uncharged for a long period of time. This situation is called sulfation and may result in premature damage to the battery.