Motorcycle Battery Terminology

A few terms that are used when dealing with motorcycle batteries.
This motorcycle battery terminology page lists the term with a brief description of what it means (the page is in alphabetical order if you scroll down the page)…..

Absorbent Glass Mat [AGM] – A sheet of microglass fibres that is used between individual battery lead plates to insulate them.

Accumulator – An electrochemical device that can transform electrical energy into stored chemical energy and by reversing the process, release energy again (basically a posh word for a battery).

Acid density – The charge state of an automotive battery can be determined by measuring the acid density in kg/l. This is done using an acid siphon.
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 level indicator – A component for displaying the level of electrolyte (battery acid) in a battery cell.

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

AGM – Abbreviation for Absorbent Glass Mat.

Ampere hours [Ah] – Measurement 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.

Battery – One or more electrochemical cells electrically coupled into a single unit and equipped with attachments for external electrical connections.

Capacity – The available quantity of electricity of a battery or cell measured in ampere hours.

Cathode – The negative electrode at which reduction processes take place in a liquid solution, i.e. where cations (positively charged ions) are precipitated (gain in electrons). In secondary cells, each of the electrodes can become cathodes depending on the direction of the current. The positive electrode is the cathode when discharging.

CCA – Cold cranking amps.

Cell – The smallest unit of a battery, consisting of a positive and a negative electrode, a separator and the electrolyte.
It stores electrical energy and forms the fundamental cornerstone of a battery if it is placed into a case and equipped with electrical connectors. The capacity of a cell is determined by its size.
The cell voltage, however, depends on the electrochemical system of the element.

Charging – Feeding electrical energy into a battery.

Charging current – The current flowing at the time a battery is being charged. It depends on the charge state, the charging method and the temperature.

Cold Cranking (cold cranking amps) – Cold Cranking Amps is a rating used in the battery industry to define a battery’s ability to start an engine in cold temperatures. The rating is the number of amps a new, fully charged battery can deliver at 0° Fahrenheit for 30 seconds, while maintaining a voltage of at least 7.2 volts, for a 12 volt battery. The higher the CCA rating, the greater the starting power of the battery (for example, a YTX12-BS battery has more starting power than a YTX9-BS battery).

Current – The movement of electrical charges in an electrical field. Battery technology only uses direct current.

Cycle – Charging followed by discharging, usually repeated at regular intervals.

Deep discharge – State in which a cell is fully discharged using low current, so that the voltage falls below the final discharging voltage.

Direct current – Current, whose polarity does not change over time (e.g. current from an electrochemical power source like a motorcycle battery).

Discharging – Drawing electrical energy from a battery in which chemical energy is converted into electrical energy.

Distilled/Purified water – Distilled or demineralized water for compensating the water losses in batteries requiring maintenance.

Electrode – A conducting structure within the cell in which electrochemical reactions take place (for example lead plates in a motorcycle battery).

Electrolyte – Also known as battery acid. Usually a fluid within the cell that allows ion movement between the electrodes.

Electrons – Elementary particles with a negative charge.

Failure – A state in which a battery no longer functions satisfactorily. There are several forms of failure.

Free electron – An electron that has broken free of it’s atomic bond and is therefore not bound to an atom.

Galvanic element – Current source whose electrical energy is released through electrochemical processes (another posh word for a battery!).

Gel – Electrolyte jellified through the addition of silicic acid to sulfuric acid.

Heavy duty – Battery type with an above-standard cycle stability and shock resistance. Commonly used in construction and farm machinery and in some motorcycle batteries.

Initial charge – The initial charge is the first charging process after the electrolyte has been poured into a dry precharged battery. It has the purpose of bringing the cell or battery to full initial capacity (this is why it is IMPORTANT to give a motorcycle battery a charge with a motorcycle battery charger before it’s 1st use!).

Lead battery – An accumulator (battery) in which the electrodes consist primarily of lead, whereas the electrolyte consists of diluted sulfuric acid.

Lead sulfate – Chemical compound produced on the positive and negative plates of a lead battery during discharge. It is the result of a chemical reaction between the sulfuric acid and lead dioxide of the positive electrode or the metallic lead of the negative electrode.

Load – Describes the current in amperes with which a fully charged battery can be loaded over a defined period and at a defined temperature without the voltage falling below a pre-specified cutoff voltage.

Maintenance free battery with fixed electrolyte – Lead-acid battery in which the electrolyte is held in place in a gel or microglass mat (AGM). The battery is sealed and is equipped with valves. It is highly stable and exhibits good cycling characteristics.

Negative terminal – Negative pole of a battery.

Nominal voltage – The battery’s average voltage during discharging with a low current strength.

Overcharging – Charging beyond the fully loaded stage. This can result in battery damage.

Oxidation – Release of electrons through the cell’s active mass to the external electric circuit. During the discharging process, cadmium is oxidized at the negative electrode of the nickel-cadmium cell or sponge lead is oxidized at the negative electrode of the lead cell.

Plug – Component with venting ducts for sealing a cell opening.

Rated capacity – The capacity in Ah (as defined by the manufacturer) under defined discharging conditions (current, temperature).

Service life – The length of satisfactory performance measured in years or charging / discharging cycles (usually a maximum of 3 years for a motorcycle battery).

Short circuit, inner – The cells can also experience an inner short circuit in the case of fine short circuits. This will generally result in high self-discharging and will be reflected in a sharp reduction in capacity.

Short circuit, outer – Low-impedance electrical contact between the battery poles. High temperatures can result in the battery being destroyed.

Specific gravity [SG] – Ratio of the weight of the electrolyte to the weight of an equal volume of water at a specific temperature. Specific gravity (or SG for short) is sometimes used to indicate the charge state of a battery.

Terminal – Polarity-specific component on the battery for making a (detachable) connection with the consumer (point on a battery where you connect your motorcycle to it).

Valve – A device allowing gas to escape when inner pressure is too high, while preventing air from entering.

Volt – Unit of measurement for electrical voltage. Abbreviation V. Named after the Italian physicist and doctor Count Alessandro Volta.

Maintenance free battery

The information provided on this page is ‘to the best of our knowledge’ and should not be taken as 100% accurate!!

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