"It’s well understood that the battery in a UPS is the most vulnerable part of the system. In fact, battery failure is a leading cause of load loss. Knowing how to maintain and manage UPS batteries will extend their life and save data center managers time and trouble in the future.Improvements in battery technology have been evolutionary rather than revolutionary. Capabilities such as advanced charging regimens, software management for accurate remaining life information and firmware adding intelligence to batteries have reduced, but not eliminated, the risks inherent in any battery. As a result, it’s prudent if not essential to take a close look at what may be increasing the risk of unexpected load loss from a failing UPS battery. After all, even large installations with many batteries are vulnerable to the failure of a single battery."
Read on for the detailed overview. Link.