Voltage-Keyed - A system which incorporates a mechanical identifier on batteries and devices to ensure only batteries of the correct voltage are connected to the device.
Cycle Life - The number of cycles under specified conditions which are available from a secondary battery before it fails to meet specified criteria as to performance.
COS phil - A measure of the phase shift between the fundamental current wave and the fundamental voltage wave observed at the terminals of a non-linear load.
Hertz - The standard unit of frequency. A frequency of one complete cycle per second is a frequency of one hertz.
Percent load - Ratio between the power Pu drawn by the load and the rated output Pn of a UPS system (Pu/Pn). Sometimes referred to as the load factor.
Spiral Wound - An electrode structure of high surface area created by winding the electrodes and separator into a spiral-wound, jelly-roll configuration.
Polarity - In electricity, the condition of being positive or negative.
