Guilty as Charged! RV Battery Use & Management

The T@b is the first RV many of us ever own. I thought I would pass along a few things I wish I had known, from day 1, about battery life and maintenance. These are things dealers should educate new RV owners about, but most often do not. I am hoping some of our battery experts will jump in and correct anything I might have wrong or add to what I have in this post. People have different views on what works best, but here is what I have found the most helpful, to me.

The Basics

• Your battery requires active management, unlike your car battery. This is not unique to the T@b. RVs, including the T@b use 12v deep cycle marine batteries, by default.
• You must ensure that you maintain the proper water levels (for lead acid batteries.) You can pick up a hydrometer and do a YouTube search for checking the battery levels in your battery. It is pretty simple stuff.
• Some people want to move the battery inside of their T@b to manage their tongue weight or for other reasons of convenience. This is OK if you have an AGM or a very well ventilated lead acid battery. Lead Acid batteries must always be well ventilated.

• You must make sure your battery does not discharge below 50%. This is unlike the lithium ion batteries you are used to using with your consumer electronics devices. A simple voltmeter will help you keep track of that.  You will ruin your battery if you let it go below more than 50% too many times. I am in the process if installing a more sophisticated battery monitor, the Victron BMV-700 to give me more detailed information. I chose the Victron model because of its high user ratings the fact that there were considerably fewer wires to deal with during installation.

• There are things that will cause a phantom battery drain. They include the LP Detector, Smoke detector, Jensen, and even the USB/12v outlets. They are very small drains, but over time will discharge your battery. When the T@b sits idle, you must maintain the charge. You can install battery cut-off switch to prevent phantom power drain as well as to prevent your TV battery from being run down when you park for a while to eat, shop, or whatever else crosses your path. I installed the Blue Sea Mini Battery On/Off Switch. There are plenty of videos on YouTube to walk you through that.

  

  You can also keep it maintained by plugging it in at home (using a pigtail adapter) or by using a solar panel to keep it charged. I have the Goal Zero Maintainer, which is a solar trickle charger. Lastly, you can opt to pull the battery from the T@b and charge at home, using a battery tender.

Most dealers install something like a 100ah Interstate Group 24 battery. This is sufficient to use for running the lights and a little use of the fan or water pump. It is not great, on its own for boondocking for more than a night or two. If you plan to boondock, you will want either 120 watts or more of solar, to upgrade the batteries to 2 6v golf cart batteries, upgrade your 12v battery or add a second 12v battery, or to use a generator. You can do any or all of these options to extend your use. The golf cart batteries will increase your amp hours from 100 to 225. I will post more about my dual golf cart battery set up in another post.

Fuses

There is a 30 amp fuse connected directly to the battery. Make sure to check this fuse when troubleshooting 12v power issues in addition to the fuses in the convertor. FYI, to tell if a fuse is blown, pull the fuse and look at the wire that goes between the 2 prongs inside of the fuse. If that is broken, the fuse is blown. On the T@b there is a fuse on the battery (positive wire) and fuses are also found in the converter, which is located on the driver side bench. I picked up a multi-pack of fuses that glow when they blow so it makes it easy to identify whether a blown fuse is your problem or not.

Battery Management

The fan, Jensen, water pump, outside light and light above the kitchen sink (at least on my 2015) seem to use the most power. You can help extend your battery life by using other battery operated lights. The 3 way fridge on battery should only be used for short periods of time (15 min) or if being charged by the TV. There is a pretty broad range of TV charging efficiency when it comes to battery charging and using the fridge. My 2011 Jeep Wrangler Unlimited Sahara, can’t quite keep up with charging and fridge use. The 2 way fridge uses less battery than the 3-way, but will still be a huge power draw. There are a few threads on this topic. Search for: Normal battery drain.

I supplement my battery use with Goal Zero battery packs and lighting. I like that I can use these items without worrying about running down the T@b batteries and they give me the flexibility of charging and working outdoors.

I have also started using AA battery operated fairy lights. They really provide a nice ambient light and I don’t have to worry about running down the T@b battery. I also enjoy using solar powered colored Luci lights to decorate the outside of my T@b.  They are fun and provide a little soft light without making your neighbors feel like they are camping on the Vegas strip.

I have created a little Power Consumption worksheet  to help me “budget” my battery usage.

When I purchased an RV, I had no idea that I would need to learn so much about watts, volts, and fuses. But, if you learn it in bite-sized chunks you will find it quite manageable. You might even enjoy the challenge!