Whenever you drive your car, absolute power is necessary. Without a power source, your car will not work at all. Power is needed to start the ignition sequence, turn on your headlamps, and activate your warning and safety lamps. Every modern vehicle relies on a battery to perform all these tasks. With a good battery, the power is definitely yours.
What are Auto Batteries?
Car batteries are also called starting-lighting-ignition (SLI) batteries. Unlike conventional dry-cell batteries, auto batteries are rechargeable units charged by the alternator mechanism when the car is running. Most auto batteries power three important features of your car while the rest of the power comes from the alternator:
Ignition sequence. For the engine to start, it needs a source of electricity. The alternator cannot work unless the engine is running. The battery, which stores power to activate the ignition sequence, is the most reliable source of electrical sparks needed to activate the spark plugs and the ignition system.
Lighting and safety. The headlamps, interior lamps, indicator lights, and horn all need electricity to work properly and safely. Lamps and other safety features of your car need a reliable power source, that comes from the battery.
Starter motor. For the moving parts of your engine to start and function efficiently, the entire engine relies on the starter motor. The starter motor needs a constant, reliable source of power to start the engine, that can only come from the battery.
How Auto Batteries Work
Like dry-cell batteries, auto batteries store and discharge electrical current through a chemical reaction. The metal plates and electrolyte acid inside the battery undergo a chemical change when the circuits are closed. The reaction causes electrons to be discharged from the battery, and the electrons are then passed through conductors in the terminals to be converted to electrical charges that your car can use.
When the battery recharges, the chemical process is reversed, and the plates return to their original state. The process repeats itself until the battery plates degenerate, or the battery acid decomposes. Batteries last a very long time, although they need to be replaced when they deteriorate.
A battery has four important parts:
Battery case. The case holds the components and parts of the batteries together. A case also acts as an insulator to prevent voltage, acid, and other chemical by-products from leaking out. Earlier types of batteries had very thick cases, usually made from rubber or rubberized plastic. Today’s batteries have a thinner case made of hard plastic or polymer compound. The thinner case makes it possible for manufacturers to add more acid to the battery, and expand the surface area of the plates.
Metal plates. Certain metals discharge electricity when submerged in an electrolyte solution. Most batteries use lead plates separated by plates of lead oxide, although other high-performance and high-capacity batteries use other metallic compounds.
Battery acid. For the metals to release electrical current, they need to be submerged in a solution that allows them to undergo chemical change. A very corrosive acid is used to transform the plates and allow them to release electrons. The acid is usually a mixture of sulfuric acid and water.
Terminals. Batteries need terminals and conductors to release electricity. Like in a conventional battery, there are two terminal poles in an auto battery: one positive pole and one negative pole. Conductive material like copper or steel is used to make battery terminals. Conductor metals are treated with special chemicals to prevent major corrosion damage when some of the battery acid or acid vapors leak out from the battery case.
Types of Auto Batteries
The most common and readily available battery used for almost all cars is a lead-acid battery. There are different types of lead-acid batteries available on the market:
Flooded batteries. Also called “wet-cell batteries,” flooded batteries are the most common types of batteries used by cars. A flooded battery uses plates submerged in liquid acid. Conventional wet-cell batteries are cheap and easy to make, and are used in almost every vehicle.
Absorbent glass mat (AGM) battery. AGM batteries use special woven glass fibers to hold the battery acid. AGM batteries are very expensive, and are used for high-performance applications and in vehicles like motorcycles. The design of the AGM battery makes it possible to use purer lead compounds and higher concentrations of acid.
Gel battery. Unlike flooded batteries, the acid in gel batteries are mixed with silicates to keep the acid from evaporating or spilling out. Gel batteries can withstand heat better than conventional wet-cell batteries, and eliminate the problem of corrosion and leakage.
Absolute power may corrupt people absolutely, but this is certainly not the case for cars. With the right power and kind of battery, you’re assured that you’re backed up with the right amount of power for just about every destination you can think of.