Terms used in conjunction with a cell or battery that utilizes lead and lead peroxide as the active plate materials in a diluted electrolyte solution of sulfuric acid and water. Nominal cell voltage about 2.1 volts.

A higher oxide of lead present in charged positive plates and frequently referred to as lead peroxide.

A lead salt formed by the action of sulfuric acid on lead oxide during paste mixing and formation. It is also formed electrochemically when a battery is discharged.

The duration of satisfactory performance, measured as usage in years or as the number of charge/discharge cycles.

Main aircraft battery built with safest chemistry in Lithium ion batteries, a cathode material of lithium iron phosphate which inhibits oxygen generation. Lithium ion aircraft batteries must be integrated into the control software and electronics of the aircraft system with redundant built in safety features.

An instrument which measures the battery voltage with an electrical load on the battery to determine its overall condition and its ability to perform under engine starting conditions or essential power requirements.

Withdrawal of small amounts of current for long periods of time from a cell or battery, usually longer than 1 hour.