Charging up your RV batteries can take a frustratingly long time, so you need to keep a close eye on them. Trust me, RVing is not as fun when your hobs are dead, your heating is shot, and your showers are freezing cold!
The fastest way to charge your RV batteries is to turn off all your appliances and let your alternator charge them as you drive. But not all RV owners use an alternator. If you’re charging with solar or shore power, you’re going to need a different approach.
This article will tell you everything you need to know about how to charge your RV batteries quickly. I’ll also give you some tips for taking care of your batteries in the long run, so you don’t waste your hard-earned money by wrecking them in the first month!
I know that RV power systems can seem intimidating; I used to feel exactly the same way. But they’re really not that complicated if someone explains them to you properly. I hope I can be that someone for you!
Fastest Way to Charge RV Batteries
The fastest way to charge RV batteries depends on your power source.
There are four main types of power sources you might be using (or perhaps you’ll be using a combination of these).
- Alternator (charges batteries as you drive)
- Solar power
- Mains electricity / shore power
- Generator (probably diesel)
- Wind turbine (quite unusual, but some full-timers use this)
No matter your power source, you will charge your batteries a lot more quickly if you turn off all your appliances first.
By the way, you can overcharge your batteries, so be careful. You need to keep an eye on how much they’re charging or get a battery manager that does this for you. (I’m not talking about employing someone to watch your batteries. It’s an electrical device!)
Alternator
If you have an alternator, your batteries will charge quite efficiently as you drive. This is great if you’re going on a road trip.
However, if you tend to park in one place for a few days at a time and don’t do much moving around, you might find that your batteries run down.
Solar Power
I run my van conversion entirely on solar. It can be really effective in sunny climates, and your batteries will charge as you drive if your panels are fixed to the roof.
To charge more quickly with solar, you want the sun to hit the panels directly. So, don’t park in the shade!
We attached our solar panels to some hinges that my husband welded together, so we can turn our solar panels at a 90-degree angle and catch the sun as it rises and sets. This makes our batteries charge much more quickly!
On a nice, sunny day, solar can charge our batteries in a few hours. In a rainy month, they might not fully charge for weeks (especially if we are using the power faster than the sun can replace it).
If you are using your RV in a hot climate and want to stay in the shade to keep cool, you can get a folding solar panel that you store in your RV. Take it out when you arrive at your camping spot and then position it in the sun while you chill underneath a tree.
A decent battery bank is essential if you’re charging via solar because you don’t have any control over the weather.
Mains Electricity
If you have an electrical hookup, you shouldn’t have to worry too much about your batteries running out. However, if you use a lot of appliances at once, you could still draw more power than you get coming in.
If you need your batteries to charge quickly, you can take them out of the van and plug them into mains electricity in your home (or a friend’s home if you’re full-time like us!).
We have done this a couple of times in the winter when we wanted to make sure we’d be good for the next rainy week in the mountains.
When I say quickly, I’m still talking several hours, so you need to think about your power in advance.
Generator
You can charge your RV batteries with a generator, too. It typically takes longer than charging from shore power or an alternator. Solar can be more or less effective depending on the size of your panels and the strength of the sun.
A generator is a good option if you’re off-grid and want to make sure you don’t run out of power.
However, it could take all day to charge your batteries, and the generator will be noisy and annoying for the people and animals around you.
Wind Turbine
Just like with solar, the effectiveness of wind turbines will depend on the weather. Wind turbines can be more effective than solar for people who park their RVs full-time in windy climates.
For example, in the Scandinavian winter, when the sun hardly ever rises, wind power would be more sensible than solar.
Just like with the other power sources, you want to turn off all your appliances to help the batteries charge as quickly as possible.
Other than that, you can only cross your fingers and hope for a blustery day.
Types of Batteries
If you’re still a bit mystified by the power system in your RV, this next section will hopefully make you feel more confident.
I don’t mean to be patronizing, but I’m going to explain it as simply as possible because it helped me when my friends explained this stuff to me in the same way.
There are four main types of batteries that people use in their RVs:
- 12 Volt Lead-Acid Batteries
- 6 Volt Golf Cart Batteries
- Gel Batteries
- Lithium Batteries
Six-volt batteries can be wired into a series of two batteries to create a “12-volt” system.
However, you won’t get any more amp hours by doing this. So, two 6-volt 50 amp-hour batteries wired in a series will give you the equivalent of one 12-volt 50 amp-hour battery.
If you want more amp hours, you need to wire your batteries in parallel. This means your voltage will stay the same, but your amps go up.
Volts Versus Amp-Hours
Batteries have a certain voltage and a certain number of amp-hours. Most RVers will have 12-volt batteries, with perhaps 100 amp-hours. The number of batteries depends on your budget and storage space!
Amps
Amps refers to how much current you have. More amp-hours means you have more time to run appliances (or you can run more devices simultaneously, but the more things you are running, the more quickly your batteries will run down).
Voltage
Volts are essentially the ‘strength’ or ‘pressure’ of the power. A higher voltage means you need a different type of appliance. (Plug a 12-volt appliance into your house and it’s going to go BANG.)
Charge Depth
Gel batteries, 12-volt lead-acid batteries, and 6-volt golf cart batteries must all remain above 50% of their charge.
If you let them get below this, they will start breaking down and stop holding a charge efficiently. You’ll end up in a constant battle to keep your batteries charged!
However, lithium batteries can go to 0% without damaging the system.
Lithium batteries are more expensive, but you actually have twice as many amp-hours to use. You see, a 100 amp-hour gel battery is good for only 50 amp-hours before it must be charged again.
If you’re thinking, Man, I just charged these batteries full and they’re empty again after an hour, it could be that you let your batteries run too low and they started to sulphurize.
Lithium batteries also charge four times faster and last about three times longer than the other kinds.
So, yes, they are expensive, but they are worth the extra cost if you can afford them. (If you can’t afford them, don’t worry. I get by just fine with my gel batteries.)
Taking Care of Your Batteries
Gel batteries and lithium batteries are both pretty low maintenance. They are easier to store because you don’t have to worry about the corrosive gas coming out of the vents or the distilled water sloshing about.
Lead-acid batteries need to be kept clean so they don’t corrode. You can clean the top of them with baking soda and water, but you need to be careful and wear thick gloves. You also need to add more distilled water when it runs low.
Lead-acid batteries can be annoying to maintain, but they are a lot cheaper because of this.
How long does it take to charge RV batteries?
It depends on the type of battery and your power source.
It takes at least several hours to charge batteries from the mains, but it could take several days to charge them via solar panels in the winter.
How can I make my RV battery charge faster?
The best way to make your RV battery charge faster is to turn off all appliances until they are charged. If you are having trouble charging quickly enough with solar or your alternator, you might want to consider plugging your batteries into the mains.
Can you charge an RV battery too fast?
Charging your RV battery quickly is OK, but overcharging it is not. So, either you need to keep a close eye on your system and disconnect the power source when your batteries are full or you need to install a battery manager that will do this for you.
Do RV batteries discharge by themselves?
Yes, your RV batteries will discharge by themselves. Even if you aren’t using them, they will lose about 5% of their charge a week. So, if you have parked your RV for the winter, it’s a good idea to go for a drive or plug the batteries into shore power at least once a month.
Final Thoughts
Many factors affect how quickly RV batteries charge. Some of these factors are simply out of our control. Make sure you plan ahead to avoid being stuck without power when it matters, and remember to keep your batteries above 50% charge unless they are lithium.
Generally speaking, you want to set aside a good day to charge your batteries if they are running low, so don’t just plug them in for 20 minutes and think you’re good to go!
I hope you found this article helpful, and I wish you many happy adventures in your RV!
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Rachel Horne
Rachel is a freelance adventure writer and founder of Highly Sensitive Nomad. When she isn’t writing, she can be found wild camping in the mountains and swimming in the lakes of Europe.
