Accumulator
An electrochemical device that can transform electrical energy into stored chemical energy and by reversing the process, release energy again. >> Secondary battery.

Acid density
The charge state of an automotive battery can be determined by measuring the >> sulphuric acid density in kg/l. This is done using an acidmeter.
The following characteristic factors apply:

Acid density 1.28 kg/l: battery is fully charged.
Acid density 1.20 kg/l: battery is half charged.
Acid density 1.10 kg/l: battery is empty.

Acid filling machine
For the filling of batteries or battery cells with acid. Two main systems are used: Level filling and volumetric filling.
Special models are used for the production of >> VRLA batteries.

Acid levelling machine
Levels the 6 battery cells of an starter battery after the >> container formation.

Acid mixing plant
Plant for mixing concentrated >> sulphuric acid with de-ionised water to the requested density.

Active mass
>> Mass, active.

Addition Agent
Material added to a past mix in small amounts for a definite purpose, such as expander ingredients in the negative paste mix.

Aging
Permanent loss of capacity due to repeated use or the effects of time.

AGM
Abbreviation for Absorptive Glass Mat. This is a mat of microglass fibres which is used for fixing the sulphuric acid in lead accumulators for maintenance-free applications.

AGM battery
>> Maintenance-free battery with fixed electrolyte.

Air leakage tester
Machine for automatic testing of the tightness of a finished battery.

Alloy
Material of metallic properties having two or more elements in a highly dispersed form.

Ampere hours (Ah)
Product of the current strength (measured in amperes) and the duration (in hours) of the current. The quantity of electricity (capacity) of a battery or cell is usually expressed in
ampere hours. Ah is the abbreviation.

Ampere (A)
Basic unit of electrical current strength.

Anode
The positive electrode at which oxidation takes place in a liquid solution, i.e. the anions (negatively charged ions) are discharged (loss of electrons). Depending on the current direction,
each of the two electrodes can become an anode in secondary cells. The negative electrode is then the anode when discharging.

Antimonial Lead
A lead alloy containing >> antimony. It is used for casting battery grids and small parts.

Antimony
A metal used to harden lead.