5 Functions of a Car Battery
June 02 2022

Did you know that a car battery can do more than just start your car? For a variety of reasons, it may be helpful to understand how a car battery works. The battery in your car is part of a finely tuned, integrated system that supports the flow of the car. If you think it's just a simple device, think again.


Let's take a look at five functions of a car battery and discover how complex it is.


1. The car's power storage car battery is the car's mobile power.

The usually rectangular, box-shaped battery is the storehouse of energy needed to start your vehicle's motor and keep it charged.

From the outside, a car battery looks like a boring block of plastic with a few connectors on top. But this plastic casing is very durable and usually acid resistant to protect the complex inner workings and materials that do the magic inside. The inside of the battery is home to a chemical solution (usually sulfuric acid) and layers of lead and lead dioxide plates, which react with the acid to produce energy.

Automotive batteries come in different voltage levels, the most common being 12 volts. A standard 12-volt car battery has six cells, each producing 2.1 volts in a fully charged state. Every 0.2 volt reduction in battery charge equates to a loss of approximately 25% of the charge. Therefore, it is critical to always maintain a proper battery charge.

There are a few things to be aware of that can drain your battery and reduce your power storage. You certainly don't want to find yourself late for work one morning, and your car won't start needing to recharge a dead battery. Being aware of these hazards will reduce your chances of being surprised by a dead battery: 

● Don't leave your headlights on!

● Don't leave your headlights on! Most newer models have automatic headlights, so you may not even notice it. But imagine you're driving someone else's car, or offering a courtesy vehicle while your car gets serviced, and it doesn't have automatic headlights. You may forget to turn them on, or you may forget to turn them off! This will quickly drain the battery.

● Make sure all your doors (interior and exterior) are closed and that no lights or electronics are running. These things are called parasitic attractors and they slowly draw energy from the battery when the car is turned off because the alternator is not actively charging.

● Check (or have your mechanic check periodically) your battery connections and terminals regularly. Over time, they may loosen or even begin to corrode. This is easy to avoid, but can damage your car's electrical system if you turn off the engine during your commute.

● If possible, don't leave your car in extreme heat or cold for too long. Whether you leave it parked in the garage or start it up and charge the battery regularly, any moderately aged battery may start to weaken at the harsh temperatures at either end of the thermometer.

● For example, if you find your car won't start or won't start after you've just driven somewhere - you drove to the supermarket and didn't have a problem, but when you return to your car with your luggage, the car will 't start - you may have a bad alternator. To start your car, you need battery power. However, when your car starts, the alternator charges the battery. So if a single driver seems to drain the life of the battery, it's likely it's not getting the power it needs while driving and you may need a new alternator.

● Simple factors such as age and overuse can also drain a battery. If it hasn't been checked or replaced in 3 to 5 years, start paying more attention to it and possibly have it tested.


2. Energy to start the engine By virtue of its energy storage, the battery contains enough energy to start the engine.

Acid and pole plate materials (lead and lead dioxide) interact in a specific sequence to produce positive and negative charges and byproduct materials. These components create a chemical reaction that produces electrons (or electricity) that flow out of the battery to start the car. Interesting fact: If you have ever used an on-board charger to charge your weak car battery, the reason it works is because the sequence of events is reversible. The charger feeds energy back into your battery. Standard 12-volt car batteries have varying degrees of power strength. the CCA (or cold start amperage) rating indicates the battery's ability to start the engine in cold conditions. Depending on the type of battery you have and the climate you live in, you may or may not have enough battery power to start your car's engine.

Many people think "more is better" so they automatically assume that a battery with a higher CCA is the right one. The right CCA for your vehicle will depend greatly on the climate you live in. A high CCA is perfect for colder climates where engines may have trouble starting. Batteries with a higher CCA have more plates and add more solution.

But this design is not a panacea. Adding more plates means they have to be thinner and tighter. In hot climates, this is not ideal because it leads to corrosion and fluid loss. CCA is the most suitable rating for North America and Europe, where it often gets cold. In other parts of the world where it is consistently hot, MCA and HCA are a better measures.

It is important to note that the available power of the battery increases at higher temperatures because the chemical reaction rate is higher. CCA (or cold-cranking amperes) measures the available current at -18°C. mca (marine start amplifier) measures the available power at 0°C, which is more helpful in warmer climates where cold weather is rare. With this rating method, the battery starting power is increased by about 20%.

Then there is the HCA (Hot Start Amplifier) which measures the power available at 26.7°C or 80°F. A good rule of thumb is that the warmer the conditions, the better the battery will start. the HCA would be the ideal rating method for use in arid and tropical climates.

That said, it's not as simple as choosing the best battery for your climate based on CA measurements. Every vehicle has a different load - or the amount of power flow required by the battery. Size is not always the best indicator either. A small car's engine may need as much starting power as a large SUV because it must start faster.

Every vehicle choice, from power windows to heated seats, places demands on the amount of current required by the battery. Fuel type is also a factor. So just because you live in a cold climate and you have a new car with all the bells and whistles, does that mean you should choose a battery with the highest CCA?

Probably not. A higher CCA is associated with possible starter damage and can shorten the life of your battery. Ask your local auto shop which battery will provide you with the best balance of power and endurance while maintaining all of your car's functions in the weather you encounter most often.

3. Provide power to the ignition system 

When you turn on your car's ignition, either by turning the key or pressing a button, you are sending a signal to the battery telling it to initiate the chemical reaction we just talked about to produce enough current to make the starter start the engine.

Basically, the battery's job during this part of the process is to dissipate a powerful, short burst of power. The coil then produces the high voltage needed to start the starter, which travels through the distributor to the spark plug and ignites the fuel in the combustion chamber.

There are various types of ignition systems, but most of the road vehicles we know today have a mechanically timed ignition consisting of multiple components that make up the circuit. There are many processes working in concert, some at the same time, and it happens very quickly, but it starts with the battery. We all enjoy the ease and convenience of the modern automobile thanks to a simple battery that acts as a catalyst for a series of fascinating processes and energy exchanges.

4. Used with alternators for power electronics

 You probably already know the first three functions, but did you know that a battery can also work in tandem with an alternator to power the vehicle's electronic processes?

That's right - the alternator (which works by "alternating" current and converting mechanical energy into electrical energy) is the component that keeps the radio, air conditioning, USB and auxiliary connections, and lights running. But if the alternator is overwhelmed, the battery must provide reliable backup power. When too many processes consume the alternator, the battery maintains the power flow by providing an energy boost.

Essentially, the alternator is the generator. The battery provides the initial burst of energy for the starter to start the engine. Nonetheless, the alternator is what keeps the electronics running and charges the battery. This is why a car battery usually doesn't run out of power while the car is running, because it is actively charged by the alternator. (But if your battery dies, don't worry Mach1 Services can help you!)

If you are a discerning person, you may want to know exactly what is happening under the hood of your car to make that alternator (alternator) run. The alternator has a wheel on it that spins once the car's engine starts running. The engine spins a set of wheels, and then the wheels spin on the alternator. It's like a mousetrap game.

With its stator, rotor, diodes, voltage regulator and cooling fan, the alternator works constantly while your car is running to maintain the flow of energy through the engine and the vehicle.

Interesting fact: Although alternators were used as early as World War II, they did not become standard in production cars until the 1960s.

Alternators can last up to seven years in good condition and with proper use, but they are also one of the most common causes of "car trouble". If the alternator dies, your car will quickly run out of battery power and die.

Alternator repair costs can range from $300 to over $1,500, depending on the vehicle and the exact cause of the problem. Warning Signs of Alternator Failure (Caution).

● Dashboard battery icon illuminates or system message says "Repair Battery Charging System"

● Dimmer than usual lights (interior and headlights) and heated/cooled seats not working properly

● Grinding sounds - the alternator has many parts, such as pulleys, bearings and belts, which wear out over time

● Smell of burning rubber - this could be the alternator belt being melted by other misaligned parts

5. Batteries help regulate voltage It is well known that power surges can damage electronic equipment. 

Well, your battery can prevent sudden power spikes from damaging your car's internal computer and ignition system from being damaged. In addition to the various types of fuse elements and circuit protection devices used throughout the vehicle, the car's battery can help regulate the power going into the electrical system. The alternator has a voltage regulator that converts the current into a current that will not damage the car's electronics. The purpose of this regulator is to always maintain the highest possible amount of voltage in the circuit. It can send signals to the alternator to generate more or less power, depending on the needs of the vehicle. Any excess power will recharge the battery. Having the battery as a backup to the alternator will protect your vehicle's system. If you suddenly disconnect the alternator from the battery, the resulting voltage surge could damage your vehicle. However, if your alternator dies and your battery takes over, the complete circuit and battery ensure slower, more regulated changes in power levels.