Spoiler Alert: It Depends on Your RV Battery Situation
Many people wonder if they should leave their RV battery disconnect switch on or off when placing their rig in storage. The answer? It depends. This article will discuss what this switch does, when you should use it, and how to install one if your rig doesn’t already have it. Let’s get started!
What is an RV Battery Disconnect Switch?
The first question we should answer is, “What is an RV battery disconnect switch?” After all, you should know how your tiny home-on-wheels works, and the battery disconnect switch might be something you find yourself using regularly.
The battery disconnect switch is exactly what you might guess: a switch that disconnects the battery from the RV. It does this by interrupting the connection between one of the battery cables and the house battery, leaving your lights, fans, and other 12-volt appliances without power. Usually, the switch is placed on the negative cable, but this isn’t always the case.
Should the RV Battery Disconnect Switch Stay On or Off in Storage?
When should you use this switch? The simple answer is to use it whenever you put your RV in storage. This keeps the batteries from being drained between camping trips. That said, there are some other things you should know before you do this.
Long-Term Storage is Different
Using the battery disconnect is a great idea when storing your rig for several days or even a few weeks. That said, if you are storing the RV for longer, you probably want to consider taking additional steps.
Even disconnected batteries will drain over time when sitting unused. This means that if you store your rig with the batteries in it for a long period of time, you will likely return to an RV with no battery power. So instead, it’s recommended to remove your batteries during periods of long storage and connect them to a battery tender to keep them up and ready to go.
The exception to this is lithium-ion batteries. In the case of these batteries, you should drain them to somewhere between 50% and 80% charge, disconnect the batteries using the disconnect switch, and fully recharge the batteries the next time you use them. This is because lithium-ion batteries can hold their charge for up to a year. Of course, if your RV will see below-freezing temperatures, you might want to take your lithium batteries somewhere warm in order to prevent cold-weather damage. Lithium batteries are best stored in a cool location but not freezing.
Leaving the Battery Connected May Be Fine
There is one situation that makes leaving your RV battery connected while in storage okay. If you will be leaving your RV plugged into power while storing it, and you have a smart converter charger with a trickle charge mode, leaving your RV batteries hooked up should be totally fine.
That said, there are drawbacks to staying plugged in all the time that you should consider before going this route. These include an increased electric bill, danger of electrical fires, and danger of cold-weather damage to batteries.
Other Times to Use an RV Battery Disconnect Switch
You might also use the switch to disconnect the battery when working on the RV electrical system or drilling into walls. This is a good idea but isn’t the only step you should take when doing such jobs. This is because activating the battery disconnect switch may not actually remove all power from your rig’s electrical system.
To ensure there is no electricity in the system, you must also unplug the RV from shore power. Additionally, some rigs have a secondary house battery that keeps a few things up and running even when the disconnect switch is activated. In these cases, you may need to disconnect the second battery manually.
Lastly, be sure you disconnect the coach battery if you’re working on a motorhome, as this might be a source of power for some items in the rig.
How to Find Your RV Battery Disconnect Switch
Not sure if you have an RV battery disconnect switch or wondering where you might look for it? Most battery disconnect switches are located on the RV control panel. This is where your tank meters, slide switches, and other RV controls are located. Look for a switch that is marked “aux battery,” “battery disconnect,” or something similar.
Installing an RV Battery Disconnect Switch
Not all RVs come equipped with RV battery disconnect switches. If you look around your motorhome or trailer and find you don’t have one, you can always just disconnect the battery manually when necessary. Another option is to install a battery disconnect switch yourself. This is both affordable and relatively simple, making it a worthwhile project for those who plan to disconnect the battery often.
The video below gives excellent, detailed instructions on installing a switch like this one on a trailer.
You will need to run either your negative or positive cable to the switch. In this video, Brian from DIY Outdoor Life uses the positive side and then runs a new piece of wire of the same gauge from the switch to the battery. All in all, it should take just a few minutes, even if you’re a beginner.
As you can see, an RV battery disconnect switch is handy, but you definitely want to educate yourself before using it. Now that you know what the switch is for and how to use it properly, go ahead and put it to work for you. If you don’t have such a switch already, consider installing one yourself!
Great article
what about when you have solar? It seems the panels will keep the batteries topped off.
M
As long as the solar charger you are using is a smart charger with a charge profile that matches the battery type you are using, that is most likely good. You will need to check periodically to ensure the panels are clear of obstruction. If you live in an area with lots of snow, panels may be more trouble than removing the batteries and maintaining them though.
I thought the failure to mention solar power was a glaring problem with this article.
My rig has solar which keeps my two lithium batteries always at 100% while in storage. I’m assuming that this is ok to do.
Good question Ron, and thanks for reading. The storage method in the article remains the same with or without solar in the case of lithium batteries.
Lithium batteries don’t need to be kept on a trickle charge and hold their charge very well for up to 6 months, and while lead-acid sulfates if undercharged for a long time, lithium has a tendency to get damaged easily by overcharging. If you have solar with a smart enough charge controller, you may get away with it, and the battery’s BMS should prevent overcharging. However, when storing, if your lithium batteries are subjected to freezing temps in the winter, charging them in those temperatures can damage the battery. Therefore, when storing, the recommendation by the solar industry is the same as the storage advice in the article, “In the case of these [lithium] batteries, you should drain them to somewhere between 50% and 80% charge, disconnect the batteries using the disconnect switch, and fully recharge the batteries the next time you use them. This is because lithium-ion batteries can hold their charge for up to a year. Of course, if your RV will see below-freezing temperatures, you might want to take your lithium batteries somewhere warm in order to prevent cold-weather damage.”
In the case of flooded lead-acid or AGM batteries, keeping the solar on with a good charge controller would be the ideal option, as it would be like connecting it to a trickle charger.
I have a fifth wheel 42 ‘ when I get my camper sat up with all the electric do I turn off my battery or leave it on
Leave it on Sandra. Your 12V DC house batteries are the “brains” of your system, running the control panels and such even though the 120 V AC are the brawn.
Should there not be a comment regarding the importance of closely monitoring electrolyte levels in wet cell batteries if they will be on constant charging by either a charger, trickle charger and/or solar charger?