There are few things as annoying or as frustrating as an RV owner than finding your battery completely dead.
That always – ALWAYS – means that you’re going to have to breakout the battery charger, hook it up to your RV, and wait (sometimes a short while, sometimes a long while) until the battery gets up to 100% again.
Making things a little bit worse, of course, is that you can’t “jump” the battery in your RV the way that you can a truck or car battery.
No, you’re going to have to go through the whole charging process – and how long that takes is going to be dictated by a handful of different things.
In this detailed guide we run through (almost) everything you need to know about charging your battery from completely dead back to 100% and how long that’s going to take.
We run through the different types of batteries you might have to charge, the biggest difference between 6 V and 12 V batteries, what “deep discharge” means in relation to these kinds of batteries, and then hit a couple of tips and tricks to speed up the process for you.
Ready to get started?
Let’s get into it!
How Long Does It Take to Charge an RV Battery?
While there is no universal rule dictating exactly how long it takes for an RV battery to charge, you can generally expect this process to take 10 hours at a minimum – and maybe 40 hours (or more) for the battery to reach a 100% charge.
As we mentioned a second ago, a lot of this has to do with the size of the battery, the type of the battery, how much juice really was left in that battery before you tossed it on a charger, and more.
Even the kind of charging system you are using will have a major impact on how quickly this process is going to take.
Just remember that at the very least it’s going to probably take 10 hours to get your battery a halfway decent charge. It might take four times as long (up to 40 hours or longer) in certain situations.
12v (Group 24)
It’s not super common for RV batteries to come in this variety, but some of the older RVs on the road today (especially some of the smaller ones) may have this kind of battery tucked inside.
This battery is going to require a minimum charge time of about 4 to 5 hours. You can speed things up a little bit by keeping the battery plugged into a trickle charger whenever it isn’t in use, but other than that you’re looking at a relatively short charging timeline (at least as far as RV batteries are concerned).
12v (Group 27)
These batteries have a bigger capacity and are a little more powerful, offer a little more range, and are generally going to need a little more time to get up to a full charge.
These batteries are going to need at least 10 hours (sometimes 12 or more) to go from completely dead all the way up to a minimum baseline. They can then continue to charge while “on the go”, though that may or may not be something that you are capable of doing while you are traveling around.
You find a lot of these batteries in RVs that have a little bit of sized them (midsized units, really), though the really big RVs usually go with a bigger battery.
12v (Group 31)
This is the kind of battery that you can find in really big RVs, a battery that is going to require at least 15 hours to charge to a minimum level – and then will need anywhere between 25 and 30 (or more) hours to get up to a full charge from there.
Dual 6v Batteries
Some people like to run dual 6 V battery configurations in the RVs that they are traveling around it. This provides a little bit more “autonomy” – allowing you to break your power bank into 26 both sections as necessary – but both batteries will have to be charged up independently.
The thing about these batteries is that they are going to take a long time to charge, even when you are using faster chargers that can pump out 25 A.
Charging on a traditional five amp charger is going to take you 25 to 30 hours (maybe a little bit longer than that). You can speed things up quite a bit by throwing these dual batteries on a 25 amp charger – but even then you’re still looking at more than seven hours of charge time just to get up to a baseline level.
What’s the Big Difference Between 6v and 12v Batteries?
As a general rule of thumb, it’s going to be your 12 V batteries that are responsible for running your “household on wheels” appliances.
This is going to be the powerpack responsible for keeping your refrigerator running, operating your stovetop or range, powering the microwave and coffee maker, and making sure that things like your water pump and other core systems have the juice they need.
12 oh batteries are also usually going to be used to power all of your “general-purpose” electricity needs as well. This could be your lighting, your TV, and other extra accessories that draw juice.
6 V batteries are usually bigger (and lighter), with larger accumulator plates and more spaced out cells for deeper discharges. They take a long time to power up but can provide you with more consistent, more reliable, and more long-lasting juice when you need it most.
That’s never a bad thing, especially if you are going to be traveling away from RV parks and other traditional hookups where you can recharge.
What Does “Deep Discharge” Mean?
When people are talking about “deep discharge” capabilities on RV batteries they are usually talking about batteries that can power core components longer than other batteries – pushing out more power over a longer stretch of time on a single charge.
This is why it’s so important to invest in quality deep charge batteries when you are powering up your RV.
It’s a big part of why people like 6 V deep charge batteries running a dual battery set up configuration. The battery plates are thicker, the ampere hours are longer, and you have a larger reserve capacity with these kinds of batteries.
Shoot for this deep discharge options whenever you can (regardless of the voltage you go with).
What’s the Fastest Way to Charge RV Batteries?
Now that we have that squared away, let’s get into the fastest way to charge your RV batteries so that you aren’t wasting any time moving forward.
Charge from the Converter
One of the fastest and most consistent ways to speed up the time necessary to charge your batteries is to charge directly from your converter.
This basically transforms your RV itself into a generator, flooding your batteries with all the power that they need and helping to cut charging times in half (and sometimes speeding things up even more).
It isn’t at all unreasonable to expect to be able to charge your batteries completely in 3 to 4 hours when it could have taken 10 or more with this approach.
Use Shore Power
This is a little bit of a controversial take, but there are lots of RV owners out there that have started to charge their batteries using “shore power” – a fuel-efficient way to get your batteries charged up without having to change up the RV power sourcing inside of your home on wheels.
Shore power is probably going to charge your batteries in a hurry, but it’s also going to run the risk of draining your shore power, too.
Truck Alternators Work, Too
There are even some RV owners that have started to charge their batteries up directly from a truck alternator.
This is definitely not something you’d want to do with a small compact car alternator, but bigger trucks – full-size and up – generally have enough “oomph” in their alternators to make this happen.
A lot of people have timed truck alternator recharging as being just as fast (if not even a little bit faster) than charging their batteries with shore power.
If you’re in a hurry this might be the way to go!