Internal Impedance - The opposition exhibited by a circuit element (cell or battery) to the flow of an alternating current (a.c.) of a particular frequency as a result of resistance, induction and capacitance.
Service Life - The period of useful life of a battery before a predetermined end-point voltage is reached.
Earthing system TT - Earthing system in which the neutral and the exposed conductive parts are directly earthed. The installation must be de-energized immediately in the event of an insulation fault.
Electrode - The site, area or location at which electrochemical processes take place.
Thermistor - A temperature sensitive resistor, usually made from specially processed oxides.
Rated Capacity - The number of ampere-hours a battery can deliver under specific conditions (e.g., rate of discharge, end voltage, temperature); usually specified by the battery manufacturer.
Tolerance in % - Limit for allowable variations for a given quantity, expressed as a percent of the rated value.
