Lead-Acid Storage Batteries for Uninterrupted Power Supply (UPS) Applications

Lead-acid storage batteries are a vital part of any UPS installation. They supply the emergency power to the load in the event commercial power is interrupted or lost. Today's UPS batteries are specifically designed for their intended applications and differ significantly from those used in communication and switchgear service. Design considerations include plate thickness, separator and retainer materials, system voltage window and specific gravity of the electrolyte. The actual installed capacity of a UPS battery for high rate application can only be accurately determined prior to shipment if the battery is factory tested from float. Laboratory tests indicate that cells that have delivered their full fifteen minute capacity when discharged from open circuit will suffer significant capacity losses, forty percent or more, when discharged from a float condition simulating actual field operation.