Causes of UPS Battery Failure

Without scheduled servicing, an Uninterruptible Power Supply system, better known as a UPS, will fail. You are particularly at risk of a UPS battery failure. As such, you will be at risk of losing vital data. Herein will explore the causes of UPS battery failure. If you have any queries, please contact us.

A common failure for the VRLA Battery is experiencing an open circuit failure, more often than not, caused by dry out. The typical structure of a UPS system is a battery system connected in a SERIES, thereby supply high current to its UPS System DC Bus. Unfortunately, if one string opens, the system cannot supply current. This means when one battery cell fails, it can bring down the entire system.

Battery Failure Caused By Temperature

Temperature variations or incorrect temperature is the most common cause of UPS battery failure. You can only get optimum performance and the manufacturer’s stated average life if the battery operates within the 22-25 ºC range. When the temperature drops below 22 ºC the battery will sustain damage while underperforming. On the other hand, operating at a temperature above 25ºC will increase battery capacity while drastically shortening battery life.

Generally speaking, every 8 ºC temperature rise cuts the battery life in half. As such, operating the battery at a temperature of 35 ºC can reduce the expected 5-10 years of battery life by half.

UPS Batteries Do Not Last Forever

Unfortunately, UPS batteries do not last forever. Even when you follow the recommended user guidelines to the letter, the UPS batteries will lose their ability to deliver power and you will be forced to replace the battery eventually. When you are buying UPS replacement batteries, ensure you buy from reliable sellers such as the UPS Battery Shop.

Battery Discharge Cycle

The number of discharge-recharge cycles is a major contributor to the reduction of battery life. Moreover, the amount of energy that a battery delivers whilst it discharges will directly influence the reduction in battery life it experiences.

The deterioration of the battery contacts is another common cause of this form of reduction of life. The constant discharging of batteries will cause the batteries to age prematurely. You should consider the short UPS activities such as compensating for sags and swells as part of battery discharge cycles.

Preventive maintenance that entails battery voltage testing, thermal image scans test to identify abnormal or hot conditions visual inspection, and retesting and re-torquing the battery terminal connections will help negate this kind of loss of life in batteries. Importantly, the test will help us determine whether a battery replacement is necessary.

Scheduled battery maintenance is important to ensure the reliability and dependability of your UPS. Preventive maintenance helps to keep the connections corrosion-free, in good working order, and also helps in identifying batteries before they fail.


If you do not take care of your UPS batteries, they will most likely fail to serve your needs as they will keep failing. Regular maintenance and the replacement of dead batteries in critical in the proper functioning of the UPS. UPS maintenance will give you insights into the state of the battery. In turn, this will help you prevent emergency failures, giving peace of mind.

UPS batteries cannot last forever, even those from Source UPS. However, the proper care, storage, and maintenance will increase the longevity of the batteries and help you identify problem areas such as failing batteries before an emergency occurs.