Specific Energy - The ratio of the energy output of a cell or battery to its weight (Wh/kg). This term is used interchangeably with gravimetric energy density.
IR Drop - A voltage drop associated with the electrical resistance (R) of a battery or current flow (I). The voltage drop is the product of the current (in amperes) and the resistance (in ohms).
Voltage Delay - Time delay for a battery to deliver the required operating voltage after it is placed under load.
Constant Resistance Discharge - A battery discharge regime whereby the resistance of the equipment load remains constant throughout discharge.
Backup time - Time during which the UPS can supply the rated load with nominal-quality power while the mains are down. This time depends on the battery and the efficiency of the UPS. Typical backup ranges from five minutes to several hours.
Energy Density - The ratio of the energy available from a battery to its volume (Wh/L) or weight (Wh/kg).
Charger - Device associated with the rectifier and used to supply the battery with the electrical power (DC current) required to recharge and/or float charge the battery, thus ensuring the rated backup time.
