What Is the Difference Between RV Battery and Marine Battery

Batteries act as electrical storage devices. It powers electric devices with the help of a reaction called electrochemical oxidation-reduction. In other words, it transfers the stored electrons from one material to another with the aid of an electric circuit.

Batteries are categorized into three different sectors: household, industrial, and vehicle.

What we’re going to be discussing today are vehicle batteries, specifically, RV and marine batteries.

RV and Marine Batteries are often used interchangeably. In fact, the distinction between them may leave users feeling confused. Is there really even a difference? Can you use a marine battery for your RV, and vice versa?

Learn more about how these batteries, while related, are remarkably different.

What Is an RV Battery?

RV batteries are what power everything that requires electricity when operating your rig. Some people don’t realize that RVs are powered with two different battery systems: the starting battery and the house battery.

Starting batteries are used to start and run the engine, just like typical cars. Because it delivers short, high-current bursts to operate the machine, it only discharges about 2 – 5% of its overall capacity.

The house battery, on the other hand, is what basically powers everything electric inside your RV – things like overhead fans, lights, coffee makers, the AC, etc. – even when the RV isn’t running. It may also be referred to as the coach battery, the house battery, or the RV battery.

These types of batteries expel less energy compared to starting batteries, which subsequently allows it to last for a longer time. Up to three or four times as long, and even longer if you’re maintaining it well.

RV house batteries are designed to be discharged and recharged repeatedly and last longer than a standard battery due to it having thicker plates.

There are two types of RV house batteries that are advertised in the market.

Both of the above are designed to sustain power over a long period of time and run until it’s 80% discharged or more.

Deep-cycle batteries are a type of lead-acid battery, and lithium batteries are, well, made of lithium.

Lithium batteries are much easier to maintain than deep-cycle batteries and have a longer lifespan. It can charge up to 5,000 cycles, whereas deep-cycle batteries have an average cycle of 400-1,500.

Due to this, they cost approximately three times as much as deep-cycle batteries, which is why it’s not often used by some campers.

What Is a Marine Battery?

Marine batteries, as its name suggests, are designed specifically for powerboats. They have plates that are heavier than standard RV batteries. Their construction is sturdy to withstand the strong vibrations and pounding that often occur on a powerboat.

It often comes in three different types:

A flooded battery uses sulfuric acid and lead plates. Unlike gel and AGM batteries, it has vented wet cells that allow excess gas to be expelled into the atmosphere. Because it isn’t sealed, it handles overcharging better than the two batteries mentioned above.

A gel battery handles the highest number of charging cycles, is spill-proof, submersible, and is practically maintenance-free. These batteries, despite high-quality standards, need to be regulated carefully to avoid damage. 

An AGM Battery uses highly porous glass mat separators. It’s considered the ‘best’ out of all three batteries because it has outstanding starting power and charge acceptance. It’s best for boaters who require fast recharging.

RV Batteries vs. Marine Batteries: The Primary Differences

Here are the most notable differences between the two:

Weight

A marine battery has thicker plates than standard RV batteries. It has greater antimony content, which allows it to provide continuous power output over long periods of time.

Voltage Stability

Marine batteries are almost 100% stable in terms of voltage. RV batteries, specifically dead-cycle lead batteries, may show a constant drop over its discharge.

Sloping voltages may not be a huge concern for RVs, as you may recharge it with a generator any time if it does occur. Marine batteries can’t have such incidents happen, especially when at sea.

Cost

Marine batteries often cost more than RV batteries, which is why some owners may be tempted to use an RV battery instead of a marine battery for their powerboats. Marine batteries will last longer and are more reliable than lead-acid batteries found in RVs. 

Some Exceptions

Is it safe to interchange RV and marine batteries?.

Marine batteries can be used to power RVs, as long as it has enough reserve to power your rig and has a slow enough discharge capacity.

On the other hand, you need to be careful when using RV batteries in your powerboat as there is a change of spilling acid when it’s operational, especially when you hit waves or have a lot of vibrations on your boat.

Lithium batteries are a great alternative option for powering boats because of their discharge and cycle lifetime.

Consider: Marine-RV Batteries

If you’re looking for a battery pack that you can use for both your RV and your boat, your best option is to purchase a Marine-RV battery.

These batteries are a hybrid of starting and deep cycle batteries. Its lead sponge plates aren’t as thick as those that are found in deep-cycle batteries but are coarser and slightly heavier than starting battery plates.

Marine-RV batteries often maintain a higher peak capacity between charges. This results in greater vehicle reliability and lower operating costs. It’ll allow you to keep your RV and/or boat to run smoothly for longer periods.  

Many RV-Marine batteries are less expensive than a battery that’s dedicated to just RVs or boats. Because they’re a split between the two, there may be a slight dip in quality and would require you to change it more often.

Takeaway

RV batteries tend to be much cheaper than marine batteries, and it may seem like a great way to save money. However, there’s a high chance that the battery won’t work as efficiently as marine batteries, and vice versa.

Marine batteries are made to be stronger, heavier, and designed to meet the needs of a modern boat. If you want your battery to last for several years of continuous use, we recommend you to buy a separate battery for each.