What Is the Difference Between the Battery and Alternator?

We’ve all been there – stuck and unable to start the car. You go to turn the key or press the button, but absolutely nothing. When a car can’t start up, your immediate thought should be to check the battery. Another component to consider is the alternator and both of which are vital electrical components. Read on to learn more about the differences between the two parts.


The car battery is a major power device that turns chemical energy into electrical energy. That energy is used to start the energy. However, none of that process would be possible with an alternator. This piece of the electrical cycle changes mechanical energy into electrical energy. In other words, the alternator resupplies the battery with power. 


One thing to point out is that your car battery uses chemical reactions, while the alternator does not. Additionally, an alternator has moving parts, such as the belt. Whereas, the battery is a singular device with wires and terminals. More importantly, the battery stores potential energy as chemical energy, whereas the alternator cannot store energy at all. That is why your engine needs to be on and running to charge the battery.

How to Differentiate Them When You Have Starting Problems

Knowing how to tell if the battery or alternator is affecting your car start-ups is a good skill to have. You can start off by visually inspecting the battery to see signs of swelling or acid leaks. However, if your electrical accessories like the windshield wipers and lighting are not working, it is likely your alternator. Plus, a failing alternator may allow you to start your engine and then shut off right after.


If you are looking for dependable battery or alternator repair, please bring your car, SUV, or truck to Strande’s Garage today.