Power source (alternate) - Backup source used in the event of a mains failure. The connection time and the duration of the source depend on the type of source used. (back)
UPS (parallel without redundancy) - A UPS made up of several (n) parallel-connected UPS units with equal output ratings (P) and each equipped with its battery, for large loads. The total output is equal to the number of units multiplied by their individual output (n x P). In this configuration, no UPS unit is redundant.
Depth of Discharge - The ratio of the quantity of electricity (usually in ampere-hours) removed from a battery to its rated capacity.
Volumetric Energy Density - The ratio of the energy output of a cell or battery to its volume (Wh/L).
Polarization - The lowering of the potential of a cell or electrode from its equilibrium value caused by the passage of an electric current.
Energy - The output capability of a cell or battery, usually expressed in watt-hours.
Metal Hydride - An intermetallic compound or alloy in which hydrogen has been absorbed; also, the negative electrode in a nickel-metal hydride battery.