Energy Density - The ratio of the energy available from a battery to its volume (Wh/L) or weight (Wh/kg).
Power Surge - Voltage above 110% of rated RMS voltage for one or more cycles.
Capacity Retention (or Charge Retention) - The fraction of the full capacity available from a battery under specified conditions of discharge after it has been stored for a period of time.
Hertz - The standard unit of frequency. A frequency of one complete cycle per second is a frequency of one hertz.
Reactance (subtransient Uscx %, for generator) - Relative measurement (%) of the internal impedance of an AC generator during harmonic phenomena. This reactance, also called the longitudinal subtransient reactance of the generator, is sometimes identified as X"d. For most common generators, the value ranges between 15 and 20%. It can drop to 12% for optimized systems and to 6% for special devices.
Electrode - The site, area or location at which electrochemical processes take place.
Reversal - The changing of the normal polarity of a battery due to overdischarge.
