Accumulator

An electrochemical device that stores electrical energy converted into REDOX chemicals and by reversing the reaction (charge x discharge), release electrical energy in DC form.

Acid density (concentration)

It is the acid content in an aqueous solution.
The specific weight of the electrolyte at a given temperature.

The state of charge of a lead-acid battery can be calculated by the acid density in g/cm3. It can be measured by an densimeter or in MF batteries it can be estimated by the built-in visual hydrometer.
This last also helps checking the acid level by the color readings.

Acid stratification

It is a sulphuric acid gradient produced inside a battery to which repeated cycling has been applied. This must be avoided, otherwise it will damage the battery. The stratification takes place usually when the battery is used for stationary stand-by energy supply. Some tips to avoid the stratification include recirculating the electrolyte, increasing the cyclic recharging voltage or sometimes physically shaking the battery if possible.

Ambient conditions

There are outside influences affecting battery temperature as well its performance and service life, for example: vibrations to which the battery is submitted, temperature variations surrounding the battery, air humidity, etc.

Ampere hours (Ah)

The quantity of energy capacity of a battery or cell.
It is proportionally related to the active paste quantity present in the battery cell.

Ampere

Basic unit of electrical current strength.

Automotive battery

An accumulator of electrical energy specifically designed for starting combustion engines.