RV batteries: types, key specs, and how to choose the right one

Shopping for RV batteries for the first time? The options can feel overwhelming fast — lithium, AGM, flooded, 6V, 12V. This guide cuts through it in plain English so you can find the best RV batteries for your setup and buy with confidence. A1 SolarStore carries a full range of deep cycle RV batteries for every setup and budget.

What is an RV battery — and is this what you need?

Your RV runs on two separate battery systems. The chassis battery starts the engine, just like a regular car battery. The house battery (or battery bank) powers everything else when you're parked without a hookup — lights, fridge, water pump, phone charger, TV.

This guide is about house batteries. If you want to run appliances while camping off-grid, you're in the right place.

House batteries are deep cycle batteries. Unlike a starter battery that fires a big burst of energy for a second or two, a deep cycle battery releases energy slowly over hours. It's also built to be discharged and recharged many times.

Types of RV batteries

There are four main types. Here's how they compare:

Flooded lead-acid (FLA)

The cheapest option up front. Lead plates sit submerged in liquid electrolyte, which means you'll need to top them up with distilled water every few weeks. They're heavy, their usable capacity tops out at around 50%, and they don't last as long as the alternatives. Serviceable for occasional weekend use when budget is the main constraint.

AGM (Absorbent Glass Mat)

Sealed, no maintenance required. The electrolyte is held in fiberglass mats — nothing to spill, nothing to top up. AGM batteries charge faster than flooded, handle road vibration well, and work in a wider temperature range. They're the most common choice for RV house batteries, and it's not hard to see why.

Gel

Gel batteries are sealed like AGM but use a silica-thickened electrolyte instead. They're more sensitive to fast charging and high heat, which limits flexibility. You won't see gel recommended much for RV use these days — AGM covers the same bases with fewer restrictions.

Lithium (LiFePO4)

Lithium iron phosphate batteries cost more up front, but the performance difference is substantial. They weigh roughly a third of an equivalent lead-acid battery, can safely discharge to 80–100% without damage, and last 2,000–4,000 cycles. A well-maintained lithium battery can run 10–15 years. For anyone spending real time off-grid, the math usually works out in lithium's favor over the long run.

Which RV battery is right for your situation?

6V vs. 12V batteries

Many RVers prefer two 6V batteries wired in series rather than a single 12V. The reason: 6V deep cycle batteries (originally designed for golf carts) have thicker lead plates, which translates to better cycling performance and longer life. Two 6V batteries in series still give you a 12V system, but with more raw capacity than a comparably sized single 12V unit.

Key specs to look at before you buy

How to size your battery bank: Add up daily watt-hours for all your appliances, divide by 12 (your system voltage), then double that number if you're using lead-acid batteries (to stay within the 50% discharge limit). Most weekend campers manage fine with 100–200 Ah. Full-timers often need 400 Ah or more.

FAQ

Whether you're looking at an RV battery replacement or building out a new bank from scratch, the right choice comes down to how often you camp and how long you want it to last. Browse A1 SolarStore's selection of batteries for RV use and find the right match for your rig.