Understanding Automotive Batteries: What They Are and How They Work

Automotive batteries are a key component in any vehicle that uses an internal combustion engine. They store chemical energy and convert it into electricity when triggered by the ignition switch.

The primary function of a battery is to deliver electric current for short periods to power your accessories and start your engine. It also regulates voltage by slowing the rate of current development.

It Provides the Juice

The battery provides electricity to power the major components of your car. These include starting the engine and lighting up the other electrical devices. It also recharges itself with the energy generated by the alternator inside the engine.

Traditional automotive batteries are usually made of lead-acid and have either a wet or dry cell design. Wet cells have a liquid mixture inside and feature a cover that can be removed to add more distilled water when necessary. Dry cells do not have a liquid and instead use an absorbent glass mat to retain electrolyte. Both battery types are class 8 hazardous materials and require special handling for shipping and transport.

Newer battery tech is transforming the way cars are powered. Lithium-ion and nickel-metal hydride batteries are now being used to replace older lead-acid units. These batteries can handle higher power draws, like those from electric-powered accessories. They can even provide power in the event of a sudden failure of the alternator.

It Absorbs Voltage Spikes

While the Automotive Battery is not the main source of energy for the car’s electrical system, it does provide extra power when needed. For example, when accessories like a stereo amplifier draw more power than the alternator can deliver in one sitting, the battery will give the system a quick boost to prevent the accessories from draining the alternator.

The battery also absorbs sudden drops or surges in power, known as voltage spikes. This is especially important if the vehicle has many high-powered accessories that call on the battery for additional energy.

Automotive batteries come in wet-cell and dry-cell types. The difference has to do with the type of liquid inside the cell: Wet-cell batteries have a port that can be opened to add fresh, distilled water. Dry-cell batteries (also called gel cells) use a thickening agent that eliminates the need to add water. Both types are class 8 hazardous materials and require special handling and shipping protocols.

It Helps Keep Electric-Powered Accessories Running

Aside from providing the jolt of electricity needed to start a car’s engine, the Automotive Battery also powers all of its electric-powered accessories. That includes everything from the headlights and radio to power seats and windows.

In addition, the battery can help stabilize voltage spikes that occur when you turn on or off accessories with a heavy electrical draw. This helps protect solid-state components like computer systems and ignition systems.

Car batteries are regulated as Hazard Class 8 — a designation that covers corrosive materials. Specifically, the acid inside of a typical automotive battery is sulfuric acid, which means that proper disposal and handling is required.

It Helps Start the Engine

The battery provides the physical cranking power necessary to start your car’s engine. This is measured in cold-cranking amps (CCA).

Inside the battery are rows of cells, each of which contains plates made of lead and lead dioxide, immersed in an electrolyte solution composed of one-third sulfuric acid and two-thirds water. When you turn on your car, the starter motor triggers a chain reaction that produces an electrical current to fire the spark plugs and create combustion.

The engine also helps keep your battery charged by creating electricity through a belt-driven alternator. This electricity is sent back to the battery and replenishes its charge through a voltage regulator. You should never use your battery to run accessories when the engine isn’t running, as this will drain its charge and significantly shorten its life. A battery that is low on fluid will lose its ability to hold a charge, so check its condition regularly. The fluid level is visible through a translucent part of the battery case.