Are you wondering how to properly store your RV or boat? Do you have a vehicle that will be sitting for a while? If the answer is yes to either of these questions, a battery maintainer might be an essential tool to keep in your storage tool kit. 

But what does a battery maintainer do exactly? Keep reading to learn when to use a battery maintainer, its advantages and disadvantages, and how to choose the best one for you. 

Let’s get started!  

What Is a Battery Maintainer?

battery maintainer is essentially a small battery charger that sends small amounts of energy to your battery. Doing so lets the battery sit for long periods of time without any activity and lets the battery retain a full charge. They can also help extend the life of your battery by preventing damage to your battery. 

The battery maintainer sends a trickle charge to your battery and can sense when it’s fully charged. At this point, it shuts off to avoid overcharging the battery, making it perfect to use when your batteries will be sitting for awhile without any use.

Battery maintainers can be a device that plugs into the wall or can work with a small solar panel.

solar battery maintainer
When you see a single small solar panel on a vehicle its usually for battery maintenance.

When Should I Use a Maintainer?

Most of the time battery maintainers are used on starting batteries for engines. Because these batteries do not charge unless the engine is running, they need a maintenance charge, hence the name.

If you have any type of vehicle sitting for two months or longer, a battery maintainer will help keep your battery charged, that way, you can instantly start your car, truck, van, or motorhome when the time comes. 

But why does the battery die when you aren’t using it? It’s because of something called parasitic drain and self-discharge. Anything connected to the battery, such as a vehicle’s computer and its electronics, will use a tiny amount of charge. While very slight, this small amount of energy can completely drain your battery over time. 

In addition, batteries have what’s called self-discharge. Due to the chemical nature of the battery, batteries lose stored energy over time, even with nothing connected to them. This problem is much greater with lead-acid batteries than lithium, however, and why a battery maintainer is critical on a lead-acid battery.

What’s the Difference Between a Battery Charger and Battery Maintainer?

You might be asking yourself, “Can’t I just use a battery charger? What’s the difference between the two?”

A normal battery charger does not stop sending voltage to a battery regardless of its state of charge. For some batteries, this can be detrimental to the battery over long periods of time. Some battery chargers have a smart mode that senses storage and will lower the voltage or shut off like a maintainer.

On the other hand, battery maintainers shut off once the battery reaches its complete charge. When the battery starts draining again, the maintainer will kick back on, making it ideal for long periods of use. 

rv battery maintainer

What Are the Advantages of a Maintainer?

Given what we’ve discussed so far, the advantages of a battery maintainer are pretty obvious–they keep your battery safely topped off so you can hit the road (or water) whenever your heart desires. 

They’ll also extend your battery life by keeping it from dying for good during cold spells. And luckily, they’re meant for long-term use, giving you extra peace of mind while your vehicle or boat sits.

Overall a small battery maintainer is much more cost-effective than a full-size charging system just for keeping a battery topped off.

What Are the Disadvantages?

Battery maintainers are fantastic for many reasons, but, of course, they have their downsides as well. For instance, you might not need one at all. If you’ll be driving your vehicle for at least 30 mins once a month, you can probably avoid the unnecessary expense and go without.

Battery maintainers are not chargers and should not be used if the vehicle has any significant loads on it. Make sure all electronics and lights are off or the battery maintainer may not do its job and you will still end up with a dead battery.

rvs and boats in storage need battery maintainers

Is It Safe to Leave a Battery Maintainer on All the Time?

So, can you really leave your battery maintainer on all the time? Fortunately, the answer is yes! Battery maintainers are designed for constant and long-term use. When used correctly, they should be perfectly safe to use as long as you need. 

It’s not a bad idea to check the maintainer every once in a while. While it shouldn’t cause any harm to your batteries, it could short out at some point. Every month or so, just check in to make sure the maintainer is still kicking. 

Do They Work with Lithium-Ion Batteries?

It depends. If you’re using a high-quality battery like our line of Battle Born Batteries that have their own built-in BMS, then a battery maintainer will keep it charged. It is likely that it will not keep it completely full, however, if the maintainer is specifically designed for lead-acid.

If, however, you are using a lithium battery without a BMS, then do not try and connect a battery maintainer as it could cause an unsafe scenario.

Thankfully, most lithium batteries don’t need battery maintainers, so this isn’t something you need to worry about. Lithium batteries have a much lower self-discharge rate and, if disconnected, will not go dead even when in storage.

→ Click here to learn more about Lithium-Ion Batteries.

How to Choose a Battery Maintainer

The main factor you should consider when choosing a battery maintainer is your battery’s voltage. Find a maintainer that will properly charge your specific battery. 

For example, the 1.25A 12V battery charger and maintainer by Battery Tender is a popular model. It can charge most power sport vehicles but doesn’t have the power to charge a car battery. 

There are also battery maintainers that can charge multiple batteries at once. If you have more than one battery in the same or different vehicles, you might consider one of these. 

Are Battery Maintainers Worth It?

Whether or not a battery maintainer is worth the expense ultimately depends on your need for one. After all, they serve a specific purpose–to keep your batteries safely charged over a long period of time. 

If you have a vehicle or boat that’ll be sitting for months on end, the answer is yes; it’s absolutely worth it to have a battery maintainer for starting batteries. You’ll have the peace of mind that your battery is safely charged, and you won’t have to buy new batteries as often! 

If however, you have a bank of lithium batteries for house power, then a battery maintainer is not the best option. Storing them charged and disconnected is your best bet.

What do you think? Are battery maintainers worth it? Let us know in the comments below! 

Want To Learn More About Electrical Systems and Lithium Batteries?

We know that building or upgrading an electrical system can be overwhelming, so we’re here to help. Our Reno, Nevada-based sales and customer service team is standing by at (855) 292-2831 to take your questions!

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