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Sizing RV Battery Bank


Choosing a battery bank size for your RV is crucial in having enough power to go off-grid camping. The first thing to consider when you are sizing RV battery bank is to determine how much space and weight carrying capacity you have available. Most battery types are heavy and take up a decent amount of room. Extra weight in your RV may require the need to be balance loads in your trailer or motorhome. In some situations, the extra weight of the battery bank may reduce some of the items you can take on the road with you.

Go Power Lithium Battery]

Go Power Lithium 100 Ah Battery

Some batteries will require outside venting: Please see our Battery choices and types for mobile solar arrays article for more information on choosing the right type of batteries for your RV.

Many Travel trailers will have the batteries on the tounge which limits total number and can create an extremely heavey tounge weight. Other batteries are loacted on one side of a camper and can create an unbalanced towing situation.

Unboxing the Go Power 100 ah battery:

When you receive your Go Power battery, it should clearly be labeled with the Go Power Brand and should have a set of terminal bolts or lugs available in the box. These are used to secure the fused battery cables to the battery.

Unboxing the Go Power 100 ah battery for the battery bank]

Once you are able to figure out how you can install, mount and safely operate batteries in your RV it is time to determine battery bank size. Most RV applications operate at 12 volts so you will most likely only parallel battery connections between them. Deep cycle marine batteries are rated in amp hours when they are designed for deep discharge. The amp hour rating of most batteries allow a user to estimate how much power a battery contains. The actual useful power depends on battery type and drain rate or the speed at which you draw power from the batteries.

A higher drain rate will drain more power than a lower drain rate. Even if your load is only 2X as much, you could actually reduce the power in the battery by 3X or 4X as much depending on load.

You want to keep most battery banks charging as much as possible. This keeps them topped off and running properly. This can be acomplished using your converter & generator, grid power, or rv solar kit.

These each offer different ways to recharge your battery bank. If you have a really good RV solar system. You can get 30 amps of charging in the full sun. In a 10 hour solar day, you could have 300 amps of charging power. Having enough battery bank to handle a 10% charge rate would be ideal. For example, if your charger is 30 amp, an ideal battery bank would be 300 amp/hours. While it may be hard to always achieve this, try to shoot for a 10% charge rate if weight, budget, and space allow. As you can see, sizing RV battery bank can be a bit of work, but it will protect your batteries and provide reliable power when boondocking off-grid in your RV.


The Go Power 100ah workhorse battery can grow to a bank of 500 ah at 12 volts. They cannot operate at voltages greater than 12 volts.

Battery Cables and fuses are important

It is extremely important to use the proper size battery cable and also always fuse the cable connected to the battery. Some times it is also nessecary to use battery mount connections when connecting multiple batteries.

The 250 ah lithium battery from Go Power is a workhorse

The 250 ah lithium battery from Go Power has been a top seller. This battery can create a very strong 12 volt battery bank. Running four of these batteries in parallel will get you up to 1000 amp hours of storage.

400 ah lithium battery priced to move

When searching on Amazon we found this 400 ah battery that looked pretty interesting. Not familiar with the brand, but the pricing was excellent.