What Does a Car Battery Do and How Does It Work?

WhatsApp
Telegram
Facebook
Twitter
LinkedIn
Pinterest
Reddit



Traditional lead acid car batteries may get overlooked nowadays with the frenzy over lithium-ion EV batteries, but these little guys are invaluable marvels of engineering which have helped power vehicles for decades.

Without the complex chemical reactions inside your vehicle’s 12V battery, you wouldn’t even be able to turn on your car or much less turn down your power windows. Read on to explore the ingenious ways in which your car battery works and how it teams up with the car’s alternator to make your car a better place to spend time.


How Does a 12V Car Battery Work?

The car battery works with chemical reactions. At its most basic, it transfers electrons between the anode (negative terminal) to where they actually want to be: the cathode (positive terminal). For example, the lead acid battery most vehicles use gets its name from the fact that it uses lead dioxide (and pure lead) plates dipped in a mixture of water and sulfuric acid.

These batteries actually have six cells that produce around 2V each, which is why car batteries are commonly referred to as 12V batteries, even though they’re not exactly 12V. These six cells are each comprised of lead dioxide plates (positive cathode) and lead plates (negative anode) that are dipped in the sulfuric acid/water mix in order to create chemical reactions that will eventually help the battery release electricity.


Keep in mind that the battery consists of six cells, and each one has various plates. But, at the core of this process is the interaction between the positive and negative terminals. When the lead dioxide of the cathode interacts with the sulfate in the acidic mixture, oxygen ions are released into the mixture where they interact with the hydrogen to produce water. Meanwhile, on the negative side, sulfate reacts with the lead in the anode, creating a lead sulfate layer in the anode and releasing electrons.

These electrons accumulate in the negative terminal and most definitely do not want to be there, but they can’t travel through the electrolyte solution, so they’re routed out through the negative terminal and through a circuit until eventually reaching the positive terminal. This is the core principle of the functionality of the car battery, as every other auxiliary device in your vehicle connects to this circuit.

But this only works while the car is off; otherwise, what’s actually powering your vehicle’s electronics is the alternator. The battery is essentially in your car to power the starter when the vehicle is off, but once the starter roars the engine to life, the alternator takes over. The alternator also charges the battery through a reversal of the processes which led to its discharge.

What Does an Alternator Do?

As previously stated, the alternator is basically doing the job people would think the battery is constantly doing. Remember, the battery would quickly drain itself if it had to power all of your windows and radio and basically any other electronic device in your vehicle. So, the solution to this is quite ingenious.

Engineers installed an alternating current generator in your vehicle powered by the engine instead of the battery. It produces enough electricity to power all of your vehicle’s electric bits. The great thing about the alternator is that it also recharges the battery while the vehicle’s engine is on because the battery does experience quite a heavy depletion after doing its job of cranking the engine.


The only problem with the alternator is that it produces alternating current, which needs to be converted to direct current. To sort this problem out, the alternating current is processed via a rectifier, which allows the alternator to pump out the required direct current.

When an alternator is going bad, you’ll begin to notice signs of this all over. For example, your vehicle’s electronics won’t act correctly, and your lights might suddenly dim. Under these conditions, your vehicle might start to throw a bunch of codes, and even if you hook it up to an OBD2 app, it probably won’t identify that the problem is actually the alternator or battery.

Worse yet, many vehicles use advanced modules which are calibrated to work with very minute tolerances. If your alternator or battery is failing, the entire car might start acting erratically and throwing codes completely unrelated to the actual problem: the failing battery or alternator.

Is a Car Battery the Same As an EV Battery?

No, they’re not the same as the battery in your EV. Lead acid batteries are significantly different from the lithium-ion batteries present in your EV. First things first, as you’ve already learned, the composition of lead acid batteries mostly consists of lead and a water/sulfuric acid mix. On the other hand, lithium-ion batteries are made up of materials like lithium, cobalt, and graphite.

Not only this, but lithium-ion batteries have a superior energy density than lead acid batteries, which is especially ideal in performance EVs and electronics, where space and weight considerations are supremely important.

Lead acid batteries also suffer from inferior life cycles compared to lithium-ion batteries. What this means is that you can recharge and discharge a lithium-ion battery many times more than you could a lead acid battery. This is obviously a huge plus for use in EVs, where the battery comprises the most important and expensive component, and a subpar life cycle would render it useless. Lead acid batteries also require regular maintenance to keep them going, whereas lithium-ion batteries are relatively maintenance-free during their lifespan.

It’s easy to see why lithium-ion batteries are used in EVs over traditional lead acid batteries. If electric vehicles used lead acid batteries, they would be insanely heavy and lack power.

Lead Acid Batteries Still Have Their Place

Regardless of the drawbacks associated with lead acid batteries, they do have their place in the automotive landscape. Their relatively cheap cost compared to lithium-ion batteries ensures that they will continue to be used in gasoline-powered vehicles and other applications where the upfront cost is an important factor.

These batteries have been powering vehicles for many years, and even though lithium-ion technology is the shiny new thing, lead acid batteries will always have their place in automotive history.



Source link

Share it with your friends

WhatsApp
Facebook
Twitter
LinkedIn
Pinterest
Reddit
Crowded Hell

Crowded Hell

Leave a Reply

Your email address will not be published.