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Does a Generator Charge Its Own Battery? (Explained)

Do you ever think of how a generator charges its battery? Well, you might wonder what the facts are. But, if you have your generator, you should know the answer.

There is nothing wrong if you don’t know how to charge the generator battery. We will show you the right way and some tips. You may be amazed to know and will get the answer on how a generator charges its own battery and does happen.

There will be some more practical information that will help you to keep your generator battery good. Let’s get to the answer.

Does a generator charge its own battery?

Not every generator charges its battery. Some particular brands like Honda manufacture generators that can charge their own battery. At the same time, the other brands and generators will ask you to charge the battery manually. Therefore, the right answer would be both Yes and No.

Let’s see whether the following brands of generators can charge their batteries on their own or not –


Two GP models, namely 15000 & 17500, are the generators that can charge their own battery. Apart from that, all the electronics generators or devices from XP can also charge their batteries. 

Portable generators also need to be charged from external outlets.

Other than these two, Generac generators cannot charge their batteries. They offer an extra charger through which you can charge the battery. If you are planning to buy a Generac generator, go for XP models. They will be your best fit in every way.


A predator generator doesn’t charge its own battery. It has come with dc cables, and you can charge it internally. And, all the portable generators need to charge from external outlets through the wires.

However, you may search by the Predator generator and charge it using DC cables. It will be effective, and the battery will last long. It won’t drain the battery.


A Duramax generator charges its battery while running. It doesn’t require any external cables to charge the battery. It is automated and will make the life battery durable.

Moreover, all the Duramax generators are automated. They charge their batteries while running. Therefore, you don’t need to worry about the charging; if you want to get a generator that can auto-charge its battery, go for Duramax.


Most of the Yamaha generators can charge the batteries while running. It’s a common characteristic. However, portable generators cannot be charged automatically.

You must go for external wires and charge from the socket using correct voltages.


Westinghouse generators don’t charge their batteries while running or automatically. You have to charge the battery manually. Then, you can start the generator.

Otherwise, Westinghouse generators won’t run, and you cannot use the electricity.


Honda generators can charge their batteries while running and automatically. You don’t need to charge the battery using any cable.

Honda portable generators are also available. If you want something unique and the best quality generator, you may get Honda as the best option.


Champion generators can charge their own battery while running at an appropriate speed. It has a good reputation for such quality.

However, if the battery gets damaged, you need to manually recharge it and then use it to run the generator. Besides, you have to plug it into the socket to charge the portable generator.


No, the Onan generator cannot charge its own battery. You will get wires or cables to charge the battery. In that case, you have to charge the battery first and then run the generator.

It will be better if you follow the manufacturer’s tips and manual user guidelines. However, the portable generator will require you to use the cable and charge with an external socket.

Does running a generator charge its own battery?

If you buy a generator that has an automatic charging system, it will charge its own battery while running. In that case, running a generator charges its own battery. In most cases, the generator will not charge its own battery while running.

We have already explained some renowned brands. You may go through it and see which brand comes with an internal charging system if you buy any of them. It will charge its battery while running with full voltages.

Apart from that, you have to charge your generator battery manually. You will get a regular cable. You need to plug it in the socket and let it charge for hours.

Here, you can follow your generator’s manual and charge it through the wires or cables. And then start using your generator.

How long does it take a generator to charge its own battery?

A generator takes 2 hours to charge its own battery. This time’s for the AC outlet. That means, if you use the AC outlet to run or charge the generator, it will take only 2 hours. However, if you go for other sockets or plugin systems, it may take longer than 3 hours too.

Moreover, 2 hours will only be applicable if your generator already has a 20% charge. But if it is unused for a long time, it may take 4 to 5 hours. In every case, your battery won’t drain. You can rely on both systems.

How does a generator charge its own battery?

A generator charges its own battery while running with full voltage. When it gets power and electric voltage properly, it will charge its battery afterward. Besides, it has an attached battery that is integrated with some wires.

Through these wires, generators pass the electricity and charge the battery. This is the standard method that a generator charges the battery.

On the other hand, if you have a manual charging system or your generator comes with an external charger, you need to plug it in. It will take the electric flow and charge the battery.

How do you keep a generator battery charged?

You can keep a generator battery charged by following some tips. They are the proven ways to make the battery charge every time.

Charge once a month:

You should charge your generator battery once a month for about 24 to 48 hours. It will help you keep a generator battery charged for a long time. You can surely use the battery for the rest of the month.

Automatic charging generators:

You should buy a generator that can charge its own battery while running. You can just ensure that you don’t let your battery go down. Be sure to have a 50% charge on the battery.

Make it 80-90%:

When you find your generator battery lifeless, you have to charge it for a long time. Try to make it 80-90% and then run the generator. Your generator will charge it thoroughly, and thus you can keep the battery charged.

New battery:

If you have used the generator for several years and find that the battery cannot afford it, it will be best to buy a new battery and keep it charged. The new battery will help your generator to run smoothly.

Check health:

If you find any unusual symptoms on the battery, you should check its health and see if anything is wrong. Sometimes, you may ask the manufacturer and get the required helo.

How to charge a generator battery?

Charging a generator battery is no longer a challenging task. If you have the automated generator, it will charge its own battery. If you have a manual one, you can follow the below steps and charge the generator.

Check the fluid level:

You should check the fluid level of your generator. You can correct the level accordingly and make it perfect. It’s a must-follow tip before you charge the battery.

Connect the wires properly:

Now, connect the red and black wire properly. First, connect the positive red wire from the battery charger to positive thermal. Then, you need to join the black wire of the charger to the battery thermal.

Keep the charger out of the socket:

Before connecting the wires, ensure that the battery charger is out of the plug and socket. If there is any electric flow, it will give you a sock and might cause a serious injury.

Plug the charger:

After connecting the wires, you need to plug the charger into an AC outlet or socket. It will be the best option to charge your generator battery. 

However, you may use other sockets too, but it cannot provide the ideal electric flow to charge the battery soon.

So, these are the four best steps to charge a generator battery. You may follow them if you have an external charging system. What if your generator can charge its own battery?

In that case, you simply run the generator and let it charge the battery for a long time.

Final Thoughts

Most times, a generator doesn’t charge its own battery. Only some selected brands can manufacture the generators to charge their batteries, namely Honda. Other than that, you have to charge the battery manually. You can follow our tips and steps to charge the generator manually.