The care and procedures necessary to keep a battery in usable condition, such as reconditioning and water addition to electrolyte of a vented cell.

A portion of the battery case enclosing the vent caps or vent valves. Sometimes with ports that can be connected overboard for ventilation.

Differences in performance characteristics between products of the same design, attributable to process deviations within expected tolerances.

Directed movement of an ion of the electrolyte under the influence of an electric field.