How Long Do I Need to Run a Generator to Charge RV Batteries?


If you own an RV, you might have the idea that how important it is to charge the RV batteries.

In order to charge these batteries, you need to either connect your RV to a power outlet or run your generator.

Factors Affecting the Charging Process

When charging the batteries of your RV through a generator, there are numerous factors to consider.

The first one is the number of batteries installed in your RV.

Secondly, you should be aware of the total amperage required to charge these batteries. For instance, if the generator produces 5 amps and the batteries need 8 amp, it won’t charge them.

In addition, you should use a powerful AC to DC converter to charge the batteries with your generator.

It’s a fast and reliable method you should always try to follow.

Another aspect is how discharged your batteries are and what is their condition (old / new, etc.)

If you want to charge them directly with the DC current offered by the generator, it would take a lot of time while charging the batteries. Moreover, it costs more in terms of fuel expenses.
How Long Do I Need to Run a Generator to Charge RV Batteries

Battery Amperes and Charging time

The overall charging time depends on the amperes required by your battery.

For instance, a battery with a 105 amp-hour capacity can take hours for a complete charge when using a small generator.

If you are using a high-output battery charger with your portable generator, you can charge your battery within less time.

To put it simply 300-watt generator can power the 10-amp chargers.

Moreover, a 600-watt generator offers sufficient power to operate a 30-amp charger. On the other hand, you can also use the battery converter of your RV for fast charging with your generator.

Safety Precautions to Take

Prior to charging the RV batteries, make sure to take the required safety precautions. This involves the inspection of the electrical and battery system.

By following these safety practices, you can ensure the protection of your RV’s electric system. Moreover, it also protects the RV against breaking out of the fire.

To avoid any damage to your batteries, take a look at their condition. If you are using the liquid acid batteries, make sure to fill the electrolyte to the desired level.

The freshly charged batteries appear to show full amperes, yet this isn’t the case. In fact, the batteries are charged quickly if they are fully drained out.

When the batteries are close to a full charge, the process of charging tends to become slow. Moreover, you should also try to prevent overcharging your batteries by checking the charge after a while.


When you are in need to charge your RV’s batteries, the best way is to connect it to the power outlet. It is the most effective, fast, secure and cost-effective way to charge the batteries.

However, if you don’t have any access to a power outlet, the alternative option you can try is using a generator.

The time taken by the generator to charge the RV batteries may vary on several parameters – there is no magic formula to find the exact time it would take.

But broadly. depends on the power offered by the generator, condition of the battery, how discharged they are and the amperage of the batteries.

About Joyce Brown

Joyce writes on how things work and product reviews, especially related to solar energy. She holds a degree in renewable energy and is passionate about making the world a better place. She is a hardcore vegan and loves to cook.