We’ll Keep the Light On For You – Finding the Best RV Battery

If you’re new to camping life, you might be wondering what all the hubbub is about RV batteries. Coming from a house or apartment, you’re used to flipping the light switch and having the lights come on. Seldom do you have to worry about where that power comes from–or for how long it will last. But oh, how different RV life can be! 

The trick is that different users put different demands on their power systems. If you’re nearly always plugged in, having great batteries probably isn’t a priority. It’s those RVers who want to explore off-the-grid destinations that will benefit most from the best batteries. 

Let’s dive in and take a close look at the options available and which one might be right for you.

Buyer’s Guide – Picking the Best RV Battery or Best Travel Trailer Battery

What Is the Best RV Battery?

There’s no one-size-fits-all answer. In order to find the best RV batteries for your travel trailer, camper, or RV, here’s a list of a few questions you’ll want to consider.

• How do you use your rig?
• How will you recharge your batteries?
• How much storage capacity do you need?
• Do you need off-the-grid AC power?
• Do you have a generator?
• What type of batteries do you have or want, and what are their service lives?

These variables go together in picking the right batteries for your RV. No one solution is right for everyone, so it requires careful consideration of how you will use your RV and what sort of power requirements you and your family realistically have.

How Do You Use Your Rig?

You are likely plugged into utilities if you’re set up in an RV park or campsite with hookups. In this case, everything in your RV will work just like it does at home which comes in handy if you use your RV for full-time living. Your RV still needs batteries, but most of your power demands come from shore power.

What if you leave the RV park to try your hand at boondocking? Or maybe you are just stopped for the night at a rest stop, and they don’t have a hookup for your power cord? 

Anytime your rig isn’t plugged in, it’s running on batteries. It’s up to you to figure out how often that happens and how much power you need to have in those instances. Is it infrequent, and all you use are a few lights? Or, are you boondocking for weeks at a time and needing the RV to be self-sufficient? 

How you answer those questions will dictate how much thought and design effort you put into your rv electrical system. Most rigs fall somewhere in the middle, where their owners want sufficient power to run a few electronics and toys while towing. They also want to park and live comfortably for a night or two in-between campsites with hookups.

How Will You Recharge Your Batteries?

Think of electricity like water and a battery as a big water jug. You can use the water (power) in the jug (battery), but eventually, it will be empty. If you run out of power, you will need a way to replenish it. This means you either need to plug in and let the battery charger do its job, or you need a generator. 

If you’re into off-the-grid living, you might also want to look into solar panels. Solar panels recharge your batteries any time the sun shines. Ideally, they top off your batteries every day. But even when they don’t do that, they add a little bit more water to the jug so that you can go longer between plug-ins.

How Much Storage Capacity Do You Need?

How big of a jug of water do you need? Figuring out how much battery capacity you should have onboard requires some hands-on research with your RV. You can get some rough ideas from internet articles and YouTube, but no one else’s rig is precisely like yours. Even if it’s close, they might use it differently. 

Your electrical appliances and consumers are thirsty friends and family drinking all the water from the jug. The more of them you invite over, the more they drink. So to figure out how big your battery bank needs to be, you’ve got to figure out how much power they’re all using.

Do You Need Off-the-Grid AC Power?

RVs have a two-circuit electrical system. On one side, there is 12 or 24-volt direct current (DC) power. This comes from the batteries or your tow vehicle’s battery and charger. The DC power circuit is used for most things in your camper, like light bulbs, fans, water pumps, and maybe even your refrigerator unless it’s propane. If you want to plug in a laptop or phone, it will need a cigarette lighter plug or a USB port charger like a car.

The other side of an RV system is the 110-volt alternating current (AC) power circuit. This supplies power to bigger items, like your air conditioner, water heater, microwave, cooktop, and maybe your hairdryer. AC power cannot be made directly from batteries–it usually comes from a power hook-up or an RV generator. 

You can make AC power from batteries with a device called an inverter (sometimes called a power converter). Inverters use DC power and convert it to AC. Inverters can be small–just enough to run a laptop charger. Or they can be huge, like an inverter generator, big enough to run your entire RV system, including air conditioning and heating. A big system takes big power–so you need to have a lot of battery power behind it to make this work.

Do You Have a Generator?

Onboard generators are big, heavy, and expensive. However, they allow you to have virtually unlimited power anywhere you go, which is a blessing if you’re boondocking in the desert during summer or get an early-season hot spell in Florida. The generator means your batteries will recharge, and your air conditioner can purr away. 

Many RVers chose to purchase small portable generators. These are a fraction of the cost of a built-in genny, but they’re also louder and require setting up and storing them for every use.

Many times, you might not want to run a generator. The more you run it, the more maintenance and fuel it requires. Plus, it’s noisy and stinky. Aren’t we boondocking to avoid noises and smells like that?

If nothing else, a generator is a handy and easy way to recharge your batteries. And no matter how good your system is, you will have to recharge it occasionally.

Types of Batteries and Their Life-Cycle Requirements

Some types of batteries need to be recharged often to last any length of time. These are well-suited for a rig that has a generator and uses it frequently or for one that spends most of the time hooked up to city power. 

Other battery types are more tolerant of being discharged and not fully recharged immediately. These are best for solar recharging or off-the-grid living. Of course, these are the more advanced chemistries, and they tend to be more expensive.

What You Should Know Before Buying RV Batteries

The first and most crucial step in considering batteries for an RV is to remember that there are different batteries for different purposes. If you have a simple system and just need the basics for a few hours, you don’t need the fanciest batteries on the market. The best battery for camper trailer uses won’t necessarily look like the best RV batteries for a Class A motorcoach.

It might seem to be backward. We commonly associate the fanciest toys with the fanciest RVs, but a Class A RV is more likely to have a generator and other charging options. In that case, it is less likely to need the best deep cycle battery for RV uses.

Best RV Battery Technologies, Chemistries, and Types Of Deep Cycle Batteries

6-Volt vs 12-Volt Options

When setting up an RV battery bank, a common question is whether or not you can use 6-volt batteries. You may find reasonable prices on these batteries since they are often used to build large banks for applications like golf carts and forklifts.

Most RVs have either 12 or 24-volt power systems. If you plug in 6 volts, what will happen? Probably nothing at all–lights out.

But it is possible to wire two 6-volt batteries together to make one 12-volt battery. This is called series wiring because wiring the two batteries in series will combine their voltage. Capacity is not doubled, however.

The same math applies if you have a 24-volt system. You could wire two 12-volt batteries in series to provide 24-volt electricity, or you could wire four 6-volt batteries in series.

Battery Capacity – CCA vs AH

Batteries have two different systems for measuring capacity–cold-cranking amps (CCAs) and amp-hours (ah). Cold-cranking amps measure how much surge power the battery can provide to crank an engine. This is the most important for a starting battery.

For the battery in your RV, you are interested in amp-hours. This is the measure of how many amps your battery could provide for one hour of operating. For example, if you have a 100 ah battery, it could provide 100 amps for one hour or one amp for 100 hours. Or it could provide 50 amps for two hours or two amps for 50 hours. You get the idea.

To apply this math to your RV, let’s say that you’ve looked at your electrical system, and your system uses about five amps of electricity every hour. Now say you want to take your RV boondocking for five days without recharging. If you use five amps every hour for 24 hours per day, you will need 120 ah of battery every day. For five days, that makes 600 ah of battery capacity.

Not all batteries can provide their entire rated power. For example, even when labeled for deep-cycle use, lead-acid batteries are rated to be discharged no more than 50 percent. So you’d need a 1,200-ah battery bank in your RV for the boondocking trip described above. 

This is much larger than most people have space to install. Most RVs have between 200 and 500 ah in their house battery bank.

Starting vs Deep Cycle RV Battery

Starting batteries are those used for engine or generator starting. They provide a burst of power to crank an engine, but they aren’t designed to provide much power for long periods. In your RV, they are sometimes called chassis batteries.

The opposite of a starting batter is a house or coach battery. These are designed for deep-cycle use. Their design is made to use power over a long period like you would use for your lights, refrigerator, and other items inside your motor home or travel trailer.

Dual Purpose Batteries

Some batteries are marketed as an in-between option–the dual-purpose battery. These can be used for either starting or house use–but they aren’t great at either one. They’re best reserved for small Class B campers vans where you use only one battery for everything. Even then, this isn’t recommended–it would be much better to install two!

Lead Acid Batteries

Lead-acid batteries are the most common type of battery. Technology has been around since the mid-1800s. Two identical lead plates are separated by a liquid electrolyte (diluted sulphuric acid). The acid is separated as the battery is charged, and various chemical reactions occur. 

The technology of the lead-acid battery is very old and very cheap. However, improvements to the design are still being made today, and you will find many different lead-acid technologies on the market to serve specific purposes. 

Lead-acid batteries are very good at providing a lot of power fast. For example, they make excellent starting batteries for cars with their high cranking power. But they aren’t very good at steadily providing a lot of power, as in running a large item for a long time. They also require being recharged almost immediately. 

If you want the battery to survive, you also can’t discharge it deeply. The rule of thumb is that a lead-acid battery should never be discharged below half of its capacity. In other words, if you’re planning an off-the-grid living solution, you need to plan to install twice as much battery capacity as you need. That way, you’ll never use more than 50 percent.

Other names used to describe lead acids include maintenance-free batteries, gel batteries, and AGM batteries. All of these batteries, despite their differences, are lead plates separated by an acid electrolyte.

Flooded Lead Acid Batteries

The most common battery technology found out there today, and by far the cheapest, are the old-school flooded batteries. The plates inside these batteries are separated by a liquid electrolyte which will burn off during use. Therefore, you must occasionally “top-up” or “water” these batteries with distilled water to keep them functional.

Flooded lead-acid batteries are everywhere. They are the basic, cheap car batteries you see for sale in big-box stores. You probably have one under the hood of your car, but they’re also used for things like golf carts and house banks in RVs.

Sealed LA Batteries

An alternative to the flooded lead-acid battery is one that is sealed and dubbed “maintenance-free.” Of course, anything that states it is maintenance-free is likely overstating things, but they mean that you don’t have to add electrolyte fluid to the batteries–ever. Another term for these batteries is VRLA or valve-regulated lead acid.

Gel Batteries

Some batteries add a silica gelling agent into the battery acid to make it thick. These gel batteries don’t allow the fluid to leak out, so the batteries can provide more consistent power in moving applications. They also can be mounted in spaces where leaking battery acid might cause problems.

Absorbed Glass Mat (AGM) Deep Cycle Battery

Lead acid AGM batteries, or absorbed glass mat batteries, are a similar design to the gel battery. This is a unique design of a deep-cycle power battery. An AGM uses a glass mat instead of using a liquid or gel electrolyte between the plates.

That means there is no chance for spillage so the battery can be mounted on its side or in awkward spaces. Generally, AGM and gel batteries are better for deep-cycle applications because they have excellent discharge performance.

Pros and Cons of Lead Acid Batteries for RVs

Pros

• Inexpensive
• Widely available
• Many sizes and capacity options
• Good for starting applications–lots of power quickly
• Extremely stable and forgiving to different charge sources and voltages

Cons

• Very large and heavy
• Only half of the capacity is usable
• If not fully recharged daily, it will lose capacity
• Lengthy recharge time–requires slow and steady recharging to reach full capacity (float charging)

Lithium Deep-Cycle RV and Travel Trailer Battery

Lead isn’t the only metal that can produce an electrochemical reaction. Many modern rechargeable batteries use lithium, which contains far more potential energy than lead. Lithium batteries are a much newer technology and more expensive, but they provide enormous benefits. A lithium battery provides far more power, weighs less, and can be discharged very deeply without damage. 

No matter what the precise chemistry is, lithium batteries are in a league of their own. They have less in common with a typical lead-acid battery than you might think. They require careful management of their charge and discharge sources. The battery will have definite operating limitations, such as the maximum charge voltages and currents, maximum output currents, and minimum operating temperatures. 

Exceeding the limitations of any battery can lead to a fire or explosion. Even lead-acid batteries can “off-gas” explosive hydrogen fumes. But exceeding the limitations on lithium systems is even more hazardous because lithium has the potential for a thermal runaway. Once started, the impending fire is nearly impossible to extinguish. This is why lithium batteries are banned from certain shipping types and on airplanes. 

The good news is that lithium technologies are constantly improving, and the ones you might install in your RV are incredibly safe. For example, lithium iron phosphate or LiFePO4 is exceptionally stable, safe, and is not prone to thermal runaway. 

Lithium-Ion vs Lithium Iron Phosphate

There is a lot of confusion about lithium batteries, which isn’t surprising considering how new and disruptive the technology is. Many consumers are familiar with the term “lithium-ion technology,” but it is applied somewhat randomly to different battery technologies.

In truth, there are many lithium-ion battery chemistries.

• Lithium Iron Phosphate (LiFePO4 or LFP) — deep-cycle RV and marine batteries, regarded as a safe and stable technology
• Lithium Cobalt Oxide (LCO) — laptops and phones
• Lithium Manganese Oxide (LMO) — power tools, some electric vehicles
• Lithium Nickel Manganese Cobalt Oxide (NMC) — e-bikes/scooters, power tools
• Lithium Nickel Cobalt Aluminum Oxide (NCA) — Tesla batteries, are regarded as more dangerous than other technologies
• Lithium Titanate (LTO) — electric vehicles, UPSs, solar or wind storage, street lights, telecom systems

The technologies in other lithium-ion batteries, like those used in Tesla vehicles, mobile phones and computers, and other consumer electronics, tend to be less-safe lithium-ion technologies that must be monitored carefully. These items have built-in circuitry to prevent thermal runaway conditions, but those complex machines sometimes fail. 

Regardless of precise chemistry, any lithium system will require a network of monitoring software and hardware to ensure that no overcharge or overcurrent conditions occur. Some batteries have all of this built-in, and others require a networked computer system known as a battery management system (BMS). The batteries sold for RV use have this technology built right into the battery.

Pros and Cons of Lithium Iron Phosphate RV Batteries

Pros

• Lightweight
• Provides long service life with very deep discharges of over 90 percent
• Can accept or provide high current for long periods of time
• Can recharge extremely quickly with no float-mode
• Does not require full recharges between use 

Cons

• Expensive
• Requires careful charge monitoring, sensitive to over voltage and over current situations
• Sudden BMS battery cutoff can destroy engine alternators
• It May require special chargers that have lithium settings due to higher charging voltages
• Limitations on use below freezing temperatures–heated batteries available for these applications

Calculating Battery Capacity Needs

Besides picking the batteries you want to use, you’ll need to buy enough of them. How many batteries do you need to buy? Well, it all depends on your energy use–or, more specifically, how many amp-hours (ah) you use every day.

Conduct an Energy Audit

To figure this out, you need to start with how many amp-hours of energy your electrical devices use when they are on and how long you run them. Make yourself a table, and include everything you want to have electricity for. Items that cycle on and off, like an electric refrigerator, are a little more complex. You’ll have to estimate how long it stays on every day. The goal is to get a realistic idea of how much power you use.

You’ll also need to know how many amps each electrical unit uses. This is usually listed in the appliance’s specifications. 

You can make all electrical calculations with the formula Volts x Amps = Watts. 

If you have a 4-watt light at 12.5 volts, it draws 0.32 amps (4/12.5=A). Many phone and laptop chargers tell you how many amps or watts they draw on the plug.

If your RV has a battery monitor, it can tell you how many amps are flowing through your system at any given time. Simply turn everything off at the breaker panel and then turn items on one at a time. Then, record how many amps each circuit uses when the appliance is running. Alternatively, you could measure each circuit individually with a multimeter. 

Here’s a look at what your energy usage table might look like in the end.

Electrical Consumer	Power Draw (amps)	Total Run Time (hours)	Total Energy Used Per 24-hours (amp-hours)
Overhead lights (LED)	2	6	12
Fans	8	0 to 4	0 to 24
Refrigerator (12-volt)	6	10 to 16	60 to 96
Water pump	4	0.2	0.8
Phone charger, USB	1	2	2
Television	4	1.5	6
Laptop (charging + inverter)	6.5	2	13
Totals	—	—	93.8 to 153.8 amp-hours (1173 to 1922 watt-hours)

Figuring Battery Bank Needs

Now that you know how much power you will use, you can start thinking about how long you want your batteries to last between charges. Start by assuming that you will have no recharge capability.

This is where different types of campers and RVers begin to separate themselves. For example, a boondocker building an Overlanding trailer for week-long adventures might want to be off-the-grid for long periods. On the other hand, a Class A motor home might spend most nights plugged in, and when they don’t, they have a generator onboard to recharge their batteries. 

 As mentioned prior, you can’t count on your 100 amp-hour battery providing 100 amp-hours. A 100 amp-hour lead-acid battery really only provides 50 amp-hours of power. Lithium batteries are better at being deeply discharged and can use 80 or 90 percent of their rated power.

Figuring Out Overall Bank Cost

Most battery buyers want to determine how much battery they are getting in amp-hours and divide it by the cost. This figure, dollars per amp-hour, is a good starting point to compare the initial cost of the battery. But it’s only part of the story.

Batteries are also rated for a specific number of duty cycles before they need to be replaced. A duty cycle is one discharge and then recharge. So the more cycles a battery can perform, the longer it will last. 

If you aren’t actually discharging your batteries before recharging them, or you are continuously recharging them, then your batteries will last a very long time. This is why cheap lead-acid batteries can keep going for years. However, even cheap batteries can get the job done if they aren’t deeply cycled and charging sources are readily available. 

So the final step to planning your battery bank is to put all of these pieces together. It’s unfair to look at one battery and say, “Well, this one has 100 amp-hours of capacity and only costs $150.” You need to go deeper and address all of the various elements. How many of those 100 amp-hours can you use? How many times can you use those cycles?

When you look closely, the battery technologies are more closely priced than you might at first believe. Lithium batteries are costly, but they are long-lasting–rated for 4,000 or 5,000 cycles. Plus, each cycle delivers 80 or 90 percent of its rated power in amp-hours–so you need half as many of them.

Compare the lithium battery to a basic lead-acid battery, and you will find that the lead acid may be rated for 2,000 cycles at 50 percent discharges. Is it worth it to pay twice as much for the lithium battery? Chances are it will provide much more power for many more years than lead acid. 

The math must make sense for you, however. In the example above, Class A rarely left power hookups and always kept their batteries topped off. Cheap old-school lead-acid batteries will work fine and will continue working fine for decades for this rig. 

Only spend the money on fancy batteries if you want the performance of fancy batteries. A different couple in the same make and model Class A might want to go boondocking. They might have laptops and electronics and install 400 watts of solar panels on the roof. Spending money on lithium batteries will be a massive upgrade for them. They don’t need to worry about recharging their battery bank every day, and their solar panels will charge the lithium much faster than they could charge lead acids. 

If they have a big enough bank of lithium power, they might even be able to run things like the air conditioning without turning on their generator.

What Size Battery For Travel Trailer? Or a Motor Home?

Battery bank capacity and battery size are separate issues. Depending on your camper or trailer, you very well might have a pre-determined space inside your battery compartment. You might be limited to how many batteries fit in there and what size they can be. You can likely modify the setup or add another compartment, but physical space constraints exist in every setup.

The cases in which most batteries come are standardized throughout the industry. To some extent, this convention comes from the auto industry. Your car or truck comes with a specific size (physical dimensions) battery installed. To replace it, you need to replace it with one of the same “groups.”

Here’s a table of common battery groups and their physical dimensions. These are all estimates since each deep-cycle battery’s specifications are unique.

Battery Group	Dimensions in Inches (L x W x H)	Approximate Amp-Hour Capacity
U1	7.7 x 5.1 x 6.3	35 ah
22NF	9 x 5.5 x 8.2	55 ah
Group 24	10.25 x 6.6 x 9	75 ah
Group 27	12.1 x 6.6 x 8.5	90-100 ah
Group 31	12.9 x 6.75 x 9.3	100 ah
Group 30H	12.9 x 6.75 x 9-12	100 ah
Group 4D	21 x 8.5 x 10	200 ah
Group 8D	21 x 11 x 9	250 ah

So, which size batteries are the most common in RVs? The most widely used sizes are those Group 27 and 31 batteries that average 100 amp-hours capacity.

Best Battery for Camper Trailer Features

Brands That Make The Best RV Batteries

Trojan

Trojan makes a full line of deep-cycle batteries in every technology–flood lead-acid, gel, AGM, and lithium-ion. Their primary market has always been rechargeable vehicles, and they are found as OEM equipment in many golf carts and floor machines. For old-school technology, Trojan is the go-to brand for deep-cycle lead-acid batteries.

Optima

Optima batteries are physically different than other lead-acid technologies. They use high-quality spirally-wound lead plates instead of the typical flat plates. This increases surface area and produces a robust battery, but it is expensive to produce. Optima batteries are excellent choices for starting batteries or for dual-purpose batteries in things like Class B camper vans.

Renogy

Renogy is one of the biggest sellers on Amazon of batteries and renewable power systems. They manufacture gel, AGM, lithium iron phosphate batteries, solar panels, and an assortment of chargers and inverters. Unfortunately, the company receives many mixed reviews for inconsistent quality and poor customer service. 

Renogy is a US company that began as a small project by students of Louisiana State University. Their products are aimed at DIYers and are very well priced.

Battle Born

Battle Born Batteries are assembled in Reno, Nevada. They’re one of the market leaders in lithium iron phosphate battery technologies applied to RV and marine use. Their batteries are drop-ins that feature a built-in onboard BMS (battery management system).

ReLiON

Battle Born’s main competitor, ReLiON batteries, also designs and assembles its products in the US. They make high-quality LiFePO4 batteries in various sizes, including models designed for starting use and use in freezing temperatures.

Other Batteries Brands

There are thousands of brands of batteries out there. You might be familiar with some brands, especially in the automotive lead-acid battery market. Delco, Ever Start, and Interstate Batteries are just a few that make these everyday batteries. Quality varies, but generally, a deep-cycle battery will provide consistent results. 

When shopping for lithium, you’ll undoubtedly stumble upon dozens of brands that no one has ever heard of. Chinese companies are flooding sites like Amazon and eBay with hundreds of options. Unfortunately, most of these use low-quality components and won’t deliver the same level of performance or longevity that you want when buying lithium.

Low-quality and unreliable BMS safety systems could even pose a fire hazard. In other words, don’t assume that lithium batteries of the same chemistry provide the same levels of performance or reliability.

Special Use Considerations

Once you disconnect the shore power cord, RV life is different from living in a home. Batteries are just one part of the differences. Here are a few of the special considerations you might want to ponder before upgrading your battery bank.

Recharging

How are you going to recharge your batteries? Will you rely solely on your vehicle’s alternator? Are you interested in installing solar panels? How do you know if solar panels will help you? Imagine yourself boondocking for a week–no hookups and no other humans in sight. How much power do you need, and how will you recharge? Will you need a generator?

Does A Generator Charge An RV Battery?

This is a common question that new RVers have. A generator is designed to provide a lot of power when you’re away from a power hook-up. But does it recharge your batteries?

The answer is yes and no. A generator creates AC power for your wall outlets and big appliances (i.e., cooktop, water heater, or aircon). All 12-volt DC things (i.e., lights, fans, or sometimes refrigerator) are still running off the batteries.

Of course, just as when you plug into shore power, a generator can be used to power a battery charger. If this is the case, then yes, your generator can charge your batteries using a battery charger.

Solar Charged RV Batteries vs Normal Batteries

If you’re interested in solar power, you might want to consider that when you buy your batteries. Solar panels and their controllers can charge any sort of battery, but they work best with lithium. Here’s why.

Solar panels produce a finite amount of power each day. That power wanes as the sun’s angle gets lower–in other words, you get only a few good hours every day around noon and very little power at any other time. If you need to recharge your batteries a considerable amount, then you’re going to need a lot of solar panels catching those few hours of sun. The top of your RV is only so big.

There are a lot of advantages to lithium batteries, but the biggest one is that they are always ready to accept any amount of charge. Lead-acid batteries, on the other hand, require a specific charge profile. They accept a lot of current until they are 80 percent charged, and then they accept less and less. To charge a lead-acid battery to 100 percent takes many hours of low-current charging. This is hard to do when you’re catching the sun.

Finally, remember that you should recharge lead-acid deep-cycle batteries to 100 percent every day to achieve their rated life span. If you don’t have enough solar panels to make that happen, your battery capacity will gradually wane.

This is not the case with lithium, which can charge any amount without losing capacity. In other words, if a weak solar day only gets you from 50 to 70 percent at the end of the afternoon, no harm is done.

RV Batteries for Cold Weather vs Hot Weather

If you use your RV during cold weather spells, you’ll want to pay special attention to your battery’s limitations. Many battery chemistries, lead-acid and lithium, cannot be charged in freezing conditions. This temperature limit refers to the battery cells, which are ideal inside your RV and heated to some extent. If you have exterior battery compartments, you’ll want to pay extra attention.

Some lithium battery companies get around this by integrating electric heating elements into the battery cases. That way, when a charge current is detected, the battery warms itself before charging.

How to Maintain/Upkeep an RV battery?

You need to consider not only how you are going to recharge your batteries when using them heavily and cycling them, but also how you are going to maintain them. Like many other discussions about batteries, this one also depends on what type of batteries you have.

Lead-acid batteries are the most sensitive. Everyone has experience with a car that has sat too long and won’t start. Lead-acid batteries self-discharge quickly. And as we have discussed, a battery that discharges below 50 percent may not come back and could be permanently damaged.

For these reasons, you need a battery charger and maintainer that will keep your battery safely at 100 percent during storage periods. If you have solar panels, these will likely perform the job since you will be using very little power. If you have access to shore power during storage, you can use a simple battery charger with a storage setting appropriate to your batteries.

Lithium batteries work differently. First, they don’t self-discharge much. Second, they should not be stored at 100 percent–it’s preferable to store a lithium battery between 50 and 70 percent charged.

This is easier said than done since most solar controllers and battery chargers are designed to keep a battery at 100 percent. The best thing to do is to leave the chargers off and make sure the system does not get too low. Speak with your battery manufacturer about their recommended storage settings with the equipment you have. A little bit of planning can go a long way in keeping those expensive batteries in tip-top shape.

Service Life – How Long Should RV Batteries Last?

If you do everything right, how long should an RV battery last? Many people get five years or more out of lead-acid batteries, but it’s tough to tell the correct answer. After all, how batteries are used and maintained varies radically from one owner to the next.

Best RV Deep Cycle Battery Options Reviewed

Drop-In Lithium Batteries – Best Battery for Travel Trailer or Off-the-Grid RV

Drop-in lithium iron phosphate (LiFePO4) batteries offer so many benefits that it’s easy to see why many RVers are leaping into lithium batteries. They are expensive. But when you compare the specs side-by-side with lead-acid options, you’ll see that these batteries last so much longer, and you get so much more power out of every charge that the price is much closer than it first appears.

Of course, they aren’t for everyone. These batteries are popular with RVers who are off-the-grid more often than not. If you’re plugged in most of the time, high-quality lead acids will last practically forever. However, if you regularly drain your batteries or use solar power to squeeze out a few more days of boondocking, then lithium will make your life a lot better.

Battle Born LiFePO4 Deep Cycle RV and Camper Batteries

Battle Born is the go-to name in LiFePO4 batteries right now. They offer outstanding customer support, a great warranty, and a fantastic price for a first-rate product. Battle Born Batteries are designed and assembled in the US with top-quality components. Their main product is a simple 12-volt, 100 amp-hour, the deep-cycle battery that can be used for many different types of uses. 

Pros

• Lightweight
• Rated for 90-percent depth of discharge
• Rated for 3,000-5,000 cycles
• Industry-leading 10-year warranty
• Designed and assembled in the US
• UL-listed

Cons

• Not recommended for starting battery use
• Expensive
• Operates at slightly different voltages from lead acids and may require special chargers
• Should not be charged in freezing temperatures

Stats

• Integrated BMS (battery management system)
• Weight: 29 pounds
• Maximum current: 100 amps (200-amp surge for 30 seconds)

ReLiON RB100-LT Low-Temp LiFePO4 Battery

Battle Born’s primary competitor in the market is the lesser-known ReLiON battery. It has very similar specs but sells for a few more dollars. ReLiON markets its batteries to a broader range of users, including RVers, boaters, golf carts, electric vehicles, and other heavy equipment users.

While ReLiON makes a battery nearly identical to the Battle Born 100 ah, the RB100 offers a unique option if you camp in cold weather. Traditional LiFePO4 batteries cannot be charged when the cells drop below freezing. This battery is optimized for cold weather with an integrated heating element. It uses a little bit of power to keep the battery at the optimum temperature for charging, allowing you to use it down to -4º F/-20º C. If you live in a cold area or plan on winter camping, this is the lithium powerpack for you.

Pros

• Can be charged in temperatures as low as -4º F/-20º C
• Standard Group 31 size
• UL and CE-certified
• Available without cold weather performance–RB100 battery
• Also available in 200 or 300 ah sizes, as well as 24-volt options
• Engineered in the US

Cons

• Extremely expensive

Stats

• Integrated BMS (battery management system)
• Maximum charge or discharge current: 100 amps (200 amp surge)
• Warranty: five years

Renogy Smart Lithium Iron Phosphates

Renogy offers several different models of LiFePO4 batteries. The advantage of this one, beyond its low price point, is that it offers a variety of connectivity options that allow you to monitor your battery’s performance. 

While the BMS (battery management systems) built into Battle Born and ReLiON batteries are good, they provide no external clues about what is wrong. If they shut off, your batter suddenly stops working–but you won’t know why. The Renogy Smart LiFePO4 batteries solve this problem by providing communication options, but you’ll need to purchase the monitoring panel or Bluetooth dongle separately.

Pros

• Manually-selectable “shelf mode” for storage
• Built-in auto-balancing function
• Integrated network port connects the battery to separate monitor or Bluetooth module for monitoring
• Renogy monitoring screen provides state of charge and fault information directly from the battery B087TMZMP6
• Self-heating batteries also available for low-temperature operations

Cons

• Cannot be wired in series
• Communication ports add complexity and reduce weather-proofing 

Stats

• Integrated BMS (battery management system)
• Minimum 4,000 cycles at an 80-percent depth of discharge
• Max charge: 50 amps
• Max discharge: 100 amps
• Lowest possible charge temperature: 32º F/0º C
• Warranty: five years

Best Deep Cycle Battery for RV – Standard Lead Acid Options

If lithium batteries are still a bit too expensive for your liking, keep in mind that RVers have been using deep-cycle lead-acid batteries for decades with few problems. If you remember to keep them charged and not let them discharge too deeply, you can get five years or more out of a set of high-quality lead acids.

Best Travel Trailer Battery – Renogy AGM 100 or 200 ah

Absorbed glass mat (AGM) batteries are an excellent option for most RVers. They are cheaper than lithium but more expensive than standard flooded lead acids. They provide performance similar to lead acids, but they are completely maintenance-free and will not leak or gas.

Many makers produce great AGM batteries, but the Renogy AGM battery options are inexpensive and have excellent specifications. In addition, they’re available in either 100 or 200 ah hour sizes.

Pros

• Maintenance-free
• Low self-discharge rate
• Available in 100 or 200 ah sizes
• High-current output–up to ten times battery capacity
• Can be installed on its side if necessary
• Reliable lead-acid performance without watering, leaking, or gassing
• Economical option with excellent performance

Cons

• Do not discharge below 50 percent
• Heavy
• Cycle lifespan not documented

Stats

• Weight: 124 pounds (200 ah model)
• Max charge current: 60 amps
• Warranty: two years

Best Camper Van Battery – Optima Dual Purpose Battery 55 ah

Optima batteries are uniquely designed, with spiral-wound lead plates in round chambers. Their lineup of batteries is divided by the color of the plastic tops. Red tops are for vehicle starting batteries, yellow tops are starting batteries for vehicles with heavy electrical loads, and blue tops are starting or dual-purpose batteries for RVs and boats.

The BlueTop 55ah Optima battery with the light grey case is perfect for small Class B camper vans looking to work off one or two batteries. It allows for deeper cycling than a typical automotive starting battery while providing up to 750 cold-cranking amps (CCAs).

Pros

• Perfect for Class B camper vans
• Dual-purpose–starting and deep-cycle battery
• Excellent build quality and vibration resistance
• Longer life than other lead-acid designs
• Maintenance-free and spill-proof design
• Can be mounted in any position

Cons

• Low capacity
• Expensive compared to other lead acid technologies

Stats

• Group size: 34
• Size: 10.06 x 7.94 x 6.88 inches
• Dual purpose battery: starting with deep-cycle capabilities
• Cold cranking amps: 750
• Capacity: 55 amp-hours
• Warranty: 3 years

Trojan T-1275 Flooded Lead Acid 12-Volt Deep-Cycle Batteries (Set of 2)

The biggest name brand in large-capacity flooded lead-acid batteries is Trojan. The company is the go-to for golf cart-style battery packs, and they make a variety of options to suit any need. 

The T-1275 is a sizeable 12-volt battery that packs 150 ah into one case. Unlike other options on our list, the T-1275 is a standard flooded wet lead-acid design. As a result, it requires watering and must be mounted securely in a vented compartment due to the possibility of leaking and gassing. Trojan sells the HydroLink watering system for easier watering–see it in the accessories section below.

Pros

• Very inexpensive
• Two 12-volt T-1275s will provide 300 amp-hours of capacity, compared to 225 amp-hours for two six-volt T-105s

Cons

• Flood lead acid batteries need watering
• Can leak or off the gas
• Heavy

Stats

• Group size: GC12
• Weight: 85 pounds
• Recommended uses RV, marine, cabins, golf carts, solar & wind energy, floor machine, man lift, aircraft tug & truck.

6-Volt Lead Acid Batteries – Trojan Battery T-105 Plus Four-Pack

Some RVers find that building a large battery bank with 6-volt batteries is more economical than 12-volt units. When you wire two 6-volt batteries in series, you get one 12-volt battery with the capacity rating of one of the batteries. In other words, you double the voltage but keep the same amp-hour rating.

Six-volt batteries generally start as those made for golf carts, and Trojan is the go-to name brand. These are standard flooded lead-acid cells that require regular maintenance and watering.

Pros

• Inexpensive
• Large storage capacity
• Available shipped in sets of two, four, or six

Cons

• Require two batteries wired in series to make a 12-volt system
• Flood lead acid batteries need watering
• Can leak or off the gas
• Heavy

Stats

• Size: 10.3 x 7.11 x 11.07 inches each
• Capacity: 225 amp-hours each (112 ah usable)
• Weight: 62 pounds each
• Warranty: 18 months

Best Battery and Power Accessories for RV Life

Batteries are just one part of a balanced RV power system. Here’s a look at a few other things you might want to look into to make living on the road a little more comfortable.

Battery Monitor – Victron Energy BMV-712 Smart

If you’re going to take care of your batteries, you must know their state of charge (SOC). This number is a percentage, with 100 percent meaning completely topped up and 0 percent meaning empty. It works just like a fuel gauge. 

We’ve discussed how important it is not to let your batteries get below 50 percent (lead acids) throughout this article, and you can only do this with a SOC indicator. The voltage will give you some indications, but it’s not very accurate because it drops with every piece of equipment you run.

If you are installing lithium, a battery monitor is required. Lithium’s voltage does not drop as the battery depletes, unlike lead-acid batteries. Instead, it remains constant (around 13.2 volts) from 80 to 30 percent. You are very low on power once it starts dropping noticeably and gets below 13.0 volts.

Battery Charger and Maintainer – Victron 15-amp Bluetooth Battery Charger

Since most RVs spend a lot of time in storage, a good battery charger is essential. To maintain their rated life span, lead-acid batteries must be maintained by a float charger at 100 percent during storage periods. Since you don’t want to overcharge the batteries, this requires a well-designed charger. Unfortunately, that would also cause long-term damage.

This Victron charger allows you to program settings for any battery, including lithium. 

Inverter – Renogy 1000W Inverter

If you want to use AC appliances on the road, you’ll need to either run a generator or use an inverter. An inverter converts DC battery power to the wall outlet, 110-volt AC power. 

Inverters come in every size for every need. This middle-of-the-road Renogy inverter is priced well and provides 1,000 watts of AC power. This is enough to charge any computer or run most small power tools or blenders. 

However, it’s not quite enough for big items like cooking or heating appliances. If you’d like to run your Instant Pot or electric grill, consider upgrading to the 2,000-watt model.

Both of these inverters are hardwired to your batteries and should be carefully installed. Pay special attention to the size of the cables used and comply with all codes and standards. The Renogy installation manual helps with cabling recommendations.

Solar Panels and Controller – Renogy 200W solar panel kit with MPPT controller

If you’re looking to get into solar, Renogy makes some easy kits to make it happen. This 200-watt kit comes with an MPPT solar charger. There are many options when it comes to panels and controllers, but an all-in-one kit like this makes a great starting point.

Lead-Acid Watering System – Trojan HydroLink Battery Watering System

If you have a big bank of flooded lead acids, a watering system can make your life a little easier. Trojan sells these kits based on their golf cart installations, but many RVers and even boaters have modified these systems to work with their house banks. 

Summing Up – RV and Travel Trailer Battery Choices

Batteries are a lot more complicated than many give them credit for, and picking the wrong batteries or treating your batteries poorly will cause frustration in the end. Here’s a review of our tips for setting up the best RV deep cycle battery system.

• Ensure that you have sufficient capacity in your battery bank to meet your needs for the length of time you want to be “unplugged”
• Know how deeply your batteries are discharging–invest in a good battery monitor with a state of charge (SOC) indicator
• Never discharge lead acid batteries more than 50 percent and invest in a good charger/maintainer
• If you are plugged in every night, high-quality lead acids will serve you well for years
• Deep-cycle AGM lead acids are a good compromise for most travel trailer battery needs
• If you want to boondock off the grid or install solar power, lithium iron phosphate RV batteries are worth a look

FAQs (Frequently Asked Questions)