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In this best RV battery buying guide we look at the best motorhome batteries, the best 6 volt RV batteries, and the overall best RV battery. We also look at things RV owners should consider when buying an RV battery as well as the specific types of RV batteries available. We discuss installing a battery monitor in your RV to keep up to date with how your battery is faring versus the amount of appliances you are trying to power at the same time. From there, we look at charging a deep cycle RV battery and whether a 6 volt golf cart or 12 volt deep cycle battery is better to use in an RV. Lastly, we investigate the temperature effects on RV batteries as well as answer some of the many frequently asked questions that transpire when RV owners research buying a camper battery or marine RV battery for their motorhome.
The Best RV Battery
These RV batteries from Universal are our top pick. They are hard to beat on price and come fully charged, so they are ready to go the moment you receive them. They are reliable and give a consistent amount of power. This means that RV owners can be confident that when they have several appliances running at once, the performance of each and every one of them will not be affected.
One of its benefits is that it is easily rechargeable. It can also be mounted into any position so it offers RV users a great deal of flexibility and is helpful for fishermen who need a highly capable deep cycle battery for their boats. Another advantage is its ability to absorb shocks without any cuts in power.
Dimensions: 12.17 inches x 6.61 inches x 9.16 inches
UPG #45978 UB121000 12V 100Ah
SLA/AGM maintenance free, spill proof battery
1 Year Warranty
- BrandUniversal Power Group
- Weight60 pounds
VmaxTanks prides itself on specializing in the manufacturing of very high-quality AGM deep cycle batteries. They recharge quickly, especially in comparison to standard RV deep cycle batteries, and more importantly this model can power many appliances in an RV at once.
The key to this deep cycle battery is the design, which has some of the strongest plates out there. They are custom made for the model and make using the battery incredibly easy. It also gives users confidence that they will be able to charge their appliances whenever and wherever they want.
This really is a heavy-duty battery that is built to last.
12 Volt 125Ah Group 31 AGM Deep Cycle Heavy Duty Battery
The custom made bespoke plates are military grade
Float service life span of 8 to 10 years
Designed for 99% recombination capabilities
No dangerous fumes or gases
- BrandVMAX Solar
- Weight75 pounds
One of the biggest advantages with these batteries is that they are incredibly light in comparison to some other deep cycle marine batteries on the market. Plus, they are reliable and the charge lasts an extremely long period of time.
Another benefit that many deep cycle battery manufacturers do not take enough care and attention with is the fact that this model can power many appliances in terrible weather conditions. If you’re on a boat or out and about in your RV when the weather has taken a turn for the worse, this is a huge comfort. Couple that with the fact that it has a reserve capacity of 120 minutes of constant performance, and you have yourself a fantastic RV battery.
12-Volt, 750 Cold Cranking Amps
Size: 10 inches x 6 7/8 inches x 7 13/16 inches tall
Dual SAE & 5/16 inches Stainless Steel Stud Posts. 55 Ah C20 capacity
Can be fixed into any position
Excellent shock proof capability
Cranking Amps – 870 Ampere
- Weight43.5 pounds
ExpertPower is known for using very high-quality materials to manufacture its batteries. This shines through in this rechargeable deep cycle battery, which is efficient and capable of providing power to an RV that demands either a huge amount of electricity or just to power a few small appliances.
What sets this battery apart from the majority of other deep cycle RV batteries is its ease of use. Too often manufacturers take it for granted that RV drivers are far more technologically minded than they actually are and make their batteries impossible to install without the help of a mechanic. Those that buy this battery will not suffer from such issues as it is great, even for beginners.
Makes use of absorbed glass mat (AGM) technology
Has a wide temperature range
12 volt 33 amp/10 hour
Deep cycle sealed lead acid battery with screw in terminals 7.72(l) 5.16(w) 6.34(h) total height 7.09 inch
- Weight23.2 pounds
Odyssey has built a battery for an RV that is as resistant to shocks and vibrations. As a result, it can be used on land, sea or snow and it will still power whatever an RV driver or boat captain asks of it. Furthermore, Odyssey’s confidence in its battery shines through in its two-year, full replacement warranty.
In addition, it is not unusual for these batteries to last almost a decade, which is an incredibly long period of time even for some of the best deep cycle batteries on the market. Couple that with the fact that it has a 70-percent longer cycle life when compared to conventional deep cycle batteries, and the result is an extremely reliable and consistent sealed lead battery.
Faster recharge: capable of 100 percentage recharge in 4 – 6 hours
Ability to be mounted anywhere with a non spill design
The non spill design protects against high impact shock and mechanical vibration
Also resistant to high temperatures
- Weight15.4 pounds
This VmaxTanks battery can hold a charge for an incredibly long time, despite powering many appliances within an RV. It is also designed so that any knocks or big vibrations that an RV takes, it can withstand them with ease and without any impact on performance.
One reason why is the VMAX approach to the battery plates. They are high performance as well as thicker than the majority of other battery plates on the market. The result is a better quality battery that lasts longer.
It does mean that this battery is also heavier than most others. However, VMAX includes a handle on the hardware so that users can carry it as their needs require. In addition, there’s a tough and durable protective casing so that the battery remains as good as new for a longer period of time.
Dimensions: L=7.7″ W=5″ H=6.1″
Also available as a battery kit
VMAX heavy duty lead tin alloys provide an extra margin of performance and service
Maintenance Free Operation
- ModelVMAX857 TM
This is a compact deep cycle marine battery that holds its charge for a long time. Both RV drivers and fisherman alike rave about this battery that packs a powerful punch despite its petite size. It’s compact design makes it incredibly easy to use as well as very convenient in a variety of situations.
Additionally, this UPG deep cycle battery comes fully charged, so customers can use it straightaway, making it even more convenient. Like the previously listed VmaxTanks battery, it comes with a built-in handle, so it is easy to transport from one vehicle to another.
Used in UPS backup systems, spotlights, flashlights, exit lighting & other equipment
35 Amp hours
- BrandUniversal Power Group
- Weight22.6 pounds
The way that this DieHard battery has been manufactured makes it easy to use within a variety of vehicles. For example, it is shock resistant due to its enhanced electrolyte suspension system, which is built to protect internal components.
DieHard has also tried to take into account the current day increase in temperatures, so that the battery performance is not affected. This is a rare characteristic of RV batteries yet an important one given that we often take our RVs through many different climates in a year, and those climates are subject to change rapidly. We want our batteries to last as long as possible, so it’s great to know that this DieHard battery should last.
BCI Gp 49, CCA 850, 92 AH rating
Reserve Capacity (RC):170 ; Cold Cranking Amps (CCA at 0 deg.F):775
Spill proof design provides added protection
Optimized power full-frame positive and negative plates prevent life robbing electrical shorts
- Weight60 pounds
Renogy batteries have many devoted followers who use them in their RVs or for marine purposes. Fisherman can use their boats safely, knowing that the battery will last an incredibly long time both in terms of charge but also in terms of life cycle. This is thanks to the heavy-duty lead calcium grids that only allow mild corrosion.
RV drivers can be confident that they can use several appliances at once with ease. It has a low self-discharge range, which provides reliable performance as well as the ability to work in suboptimal temperatures of below 25 degrees.
Patented design ensures that gel electrolyte is distributed evenly throughout the inner battery
Triplex Sealed Construction prevents electrolyte leakage
Equipped with explosion-proof safety valves
- Weight67 pounds
This is a great deep cycle battery to use either in a boat or an RV. Users find that they can power a handful of appliances at once with no difference in their performance versus when the appliances are connected to a fixed line grid. Plus, it charges extremely quickly.
Remarkably, it comes with a massive eight-year, full replacement warranty, which is almost unheard of in the RV battery market. They’re a fantastic investment given how long they can run without the need for recharging, especially considering the power that they can produce. Plus, their self-discharge rate is amongs the best available. RV owners have been known to leave this battery for a year and still come back to find it almost fully charged.
12 volt Drop in Lead Acid Replacement
100 amp continuous output
200 amp surge output – 30 seconds 1/2 second surge output for higher loads
3000-5000 cycles – Acceptable Charging voltages 14.4 to 14.6 volts
- BrandBattle Born Batteries
Best RV Battery Buying Guide & FAQ
Things to Consider When Buying RV Battery
Buying an RV battery can be a little overwhelming given the plethora of options on the market claiming to be the best RV battery, but also given their importance seeing as they run so many different appliances in your motorhome. Add to this that an RV battery often goes by many different names - the deep cycle battery, the coach battery, or the RV house battery, to name but a few - and you have yourself a very confusing prospect.
Here are some things we think you should consider when researching what RV battery is right for you:
- Life expectancy - how long your battery will or should last when running a number or appliances within your motorhome repeatedly. This obviously changes varying on how often and how much you use your battery.
- Power - how much power your battery can give out before appliances stop working at their optimal level. This is measured in amp hours or reserve capacity. Amp hours delineate how many amps the battery can discharge in a 20 hour period. RC refers to the number of minutes a battery can go for when providing a 20 amp output. In short, more is better when looking at the potential power of a potential battery.
- Types - Deep cycle batteries or RV batteries come in several types. One is flooded lead acid and another other is the valve regulated acid battery. Most RV batteries are flooded lead acid. The reason you need to take these types into consideration is that the valve regulated lead-acid battery will need little to no maintenance while the flooded lead acid ones do. Depending on what you use your battery for, one can be more suitable than the other. The Valve regulated sorts are better to use in water vehicles or if you are looking for a deep cycle marine battery or marine RV battery. There are now also Absorbed Glass Mat batteries that use a sealed fiberglass sponge that work to diminish the amount of electrolyte that is lost when charging.
- Size - The size of a battery largely changes the amount of AH or RC a battery has. This means that the bigger the physical size of the battery, the more power it tends to have. However, as discussed later in this guide to buying the best RV battery for your motorhome, buying the biggest battery is not always necessarily immediately better.
- Models and Prices - you obviously need to buy a battery that fits in with your budget but also answers all your needs and requirements. RV batteries are not cheap so it pays to do some research first.
Types of RV Batteries
As mentioned, there are several types of RV battery on the market. They can be a little confusing but owners should try to understand the differences so that they purchase the best type for their purpose.
For starters, there is a flooded RV battery. They are also known as a wet cell battery and are fairly common. Their design and mock-up mean that they do require some maintenance in the form of being topped up with water to act as the electrolyte. They are popular as they hold their charge fairly well especially when considering the price. However, they are not the strongest in terms of internal construction and design.
Next is an AGM battery or an absorbed glass matte battery. It is a fairly new type of lead-acid battery, which is the common characteristic across all motorhome batteries or a group 27 deep cycle battery. They’re popular as they are maintenance free as they are designed to be both spill proof and shock resistant.
Lastly, RV owners could look at a GEL cell battery for their camper battery needs. Unlike the previous two types, they use silica or sand as opposed to sulphuric acid within it as the electrolyte. They’re not great when a quick or very powerful charge is needed but they do have a stronger internal construction in comparison to the flooded battery.
Below are our top 10 RV batteries that we think are the best of the best from what is available on the market. Our top pick, above all others, is the Universal UB121000-45978 which is an exceedingly capable and reliable battery that can be used easily.
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Installing A Battery Monitor in Your RV
Some RVs claim that they come equipped with a monitor that allows owners to keep on top of how much power they are demanding from their battery and as a consequence how much energy their battery has left. Unfortunately, the monitors installed are often not able to do this accurately so owners should look into installing a battery monitor of their own into their RV.
The reason being is that this will allow you to know when is a good time to charge your battery versus when it is still so full of charge that it will do it a disservice to try recharging it. On the flip side of this, if RV owners let their deep cycle RV battery go below 20% full, this is where they could actually do their battery damage by continuing to use the appliances in their RV and run the battery down even further.
A battery monitor allows users to, therefore, see before this happens, or even allows them to ensure that they do not charge their battery before necessary. They don’t take up much space and are an investment into lengthening the life of your RV battery so that you can use it for longer, thus making the financial outlay less of a burden.
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Charging An RV Deep Cycle Battery
Charging an RV deep cycle battery is obviously key to keeping an RV up and running as well as pleasurable to use. This is because every single appliance and system in an RV runs off its deep cycle battery so that if it is dead, you won’t be able to use it. Batteries can take a little while to charge and it is a good idea to keep on top of charging them, especially if you use your RV a great deal every week or so. Here are the steps on how to charge your battery so that you always get a smooth and consistent use from your vehicle.
Steps To How To Charge An RV Deep Cycle Battery
- Firstly, it is important that you turn off your RV completely and ensure that you have turned on the emergency brake. While charging your RV’s battery should not be dangerous, setting the emergency brake will help stop any unnecessary injuries.
- Find your RV battery. Remember that your RV could have more than just the one battery, particularly if you have a larger vehicle. Additionally, the location of your battery can really vary from one model and make to the next, so consult your owner manual if you are having problems.
- By using a wrench, start to remove the battery cables from your RV battery. It is best to wear heavy duty gloves for this and be sure to take away the negative side first. This is designated by the black cable. The red cable is the positive cable and should always be removed second.
- Now is a good opportunity to clean your battery and its connections of any substance build up that could affect performance. A baking soda paste made from baking soda and water is a good cleaning solution for this. All you need to do is add the paste to the connections on your battery and then use some wire wool or a wire brush to take the paste away as well as any of the dirt. From there, remove any excess paste with a clean duster and some water. Then, use vaseline on top of the now clean connections so that they are protected from any corrosion.
- Once cleaned, refill the battery with distilled water if is needed. You can check this by opening the cap on top of the battery. Remember to use a funnel for this step so as not to get the water everywhere.
- Now attach your charger to your battery. To do this, make a positive connection initially by linking up the red sides first. Then do the same with the black, negative side. Alternatively, you can make a negative connection with a metal piece and clamp for grounding.
- Turn your battery charger on and allow the charger to do its job and recharge your RV battery in its entirety. There should be a light that will work as an indicator when the battery is full of charge once again.
- Now remove the charger by unplugging the connections.
- Start to connect the battery back to the RV. When reconnecting, it is important to remember to make the positive connection first. This will mean reattaching the red or positive cable first and using a wrench to secure it in place properly. From there, reconnect the negative side in the same fashion.
- If you have more than one battery in your RV due to its size, you will have to follow all these steps again to ensure they are charged too.
Choosing Between A 6-Volt Golf Cart or 12-Volt Deep Cycle Battery
It is sometimes necessary to choose between a 6-volt golf cart battery or a 12-volt deep cycle battery for your RV. Some RV experts argue that having two 6 volt batteries to run your RV is far better a decision than having just the one 12 volts deep cycle battery. Other experts disagree. The battery size you choose can be determined by a number of things that essentially boil down to RV make and model as well as an RV owner’s own personal choice.
To make that personal choice, RV owners will need to know the difference between the two as well as their similarities. For starters, they are both made of lead acid and contain 2.1-volt cells. However, the 6-volt battery has three cells within it in comparison to the six cells that the 12-volt battery has. This means that the 6-volt battery has more space in each cell than the 12-volt battery. This has a repercussion of the plates within the smaller battery being larger or thicker and so they are meant to last longer as well as have the ability to give out energy for longer than a 12-volt deep cycle battery. This is the main reason why some experts argue the case for having two 6 volt batteries as opposed to just the one 12 volts.
However, owners need to take into account the space that they have available in their RV too as sometimes this can mean a 12-volt deep cycle battery is a far better option. Different RV models will have different spaces available for the battery physically to fit. Often the 12 volt is actually the only option available, therefore.
Also, 6-volt batteries are lighter, obviously. Given that a 12-volt battery can weigh up to 110 pounds, owners need to take into consideration their ability to handle the battery given that they will have to move them every so often to charge them, amongst other reasons.
How Temperature Can Affect RV Batteries
Temperature can have a huge bearing on batteries and their ability to perform. This is because one of if not the only, reason behind why a battery will stop working is down to something called sulfation. Sulfation is why sulfate grows on the plates of your battery. It is very common and will occur each and every time you use your battery and then every time you charge it back up too.
However, sulfation is bad for your battery if it grows too quickly. This can happen if you store your battery somewhere that is far too hot as when they are kept in too high a temperature, the battery can actually start to dispel some of its charge which is when sulfation occurs. It is good to keep in mind too that every time the temperature increases around your battery by 10 degrees, this increase will cause your battery to start discharging at twice the rate it was before. If in doubt, room temperature is a good storage amount that should not affect your battery or the rate of sulfation that occurs.
Best RV Battery FAQ:
Q: What’s an RV Deep Cycle Battery?
A: So what exactly is an RV battery? An RV battery, in short, is what your RV uses to run everything within your RV that you will most certainly use on a daily basis. This includes water pumps and appliances like TVs, coffee machines or refrigerators. As they are used by so many things within your vehicle, they are designed so that a level amount is discharged to your vehicle over long bouts of time. This is in direct comparison to the starting battery which gives out large but short amounts of energy for short periods of time so that the engine starts from the crank having been activated.
By design, RV deep cycle batteries are meant to give out anything in between 50 to 70% of its charge - though this obviously varies according to what brand the battery is and how it is made. RV batteries are chargeable too so that they can be reused over and over again when their energy levels have been topped up by their owners.
In comparison, to the starter battery, an RV deep cycle battery looks different too in that they have very thick set plates that are not spongey or soft like the starter battery. Instead, the plates are completely solid making them have a much smaller surface area so that they would not be capable of the short bursts of power that the starter battery provides, even if the owner wanted it to. These thick plates also allow the battery to have its charge whittled down to about 20% if necessary.
They can also be used to power smaller vehicles like golf carts or even electric wheelchairs.
Q: How do I install an RV battery?
A: Installing an RV battery should be easy but it can take a little getting used to, to ensure that all the necessary steps and precautions are taken.
- Start by turning off all appliances in your RV - this includes anything like lighting or items that use the RV battery to run.
- Note down what position your battery is in when in the tray to gauge its polarity.
- Remove the old battery by disconnecting the negative cable first. At this stage, check that the carrier or battery casing and other hardware does not have any signs of rust or corrosion.
- If your battery is not maintenance free, you will need to check as well that there is the necessary amount of electrolyte inside. If not, top up your battery with properly distilled water until the right level is reached. The acid level of your battery should never be needed to be filled by you. Clean the terminal posts.
- Place the new battery into the tray so that it is in the same position as checked in previous step 2.
- Connect cables to the new battery and activate the hold-down hardware.
- Test the battery by switching on the lights.
Q: What RV batteries are made of?
A: RV batteries are primarily made of lead acid that is included in the battery’s cells. They are also made up of plates as well as lead and lead oxide. The lead oxide is covered in an electrolyte that is made up of sulphuric acid and water. It is these component parts and ingredients that give RV batteries the ability to store electricity. The amount that the battery can store is determined by the size of the plates as well as the amount of electrolyte included.
Q: How does a lithium-ion battery work?
A: A lithium-ion battery works due to the transference of positively charged lithium ions from one part of the battery to another. These are called the anode and cathode. Other parts a lithium-ion battery are the separator, the electrolyte and two current collectors that collect a positive and negative charge each. It is the electrolyte that transfers the positively charged lithium ions from the anode to the cathode. This happens through the separator and back again giving an electrical current. The separator importantly stops electrons from flowing into the battery. The current collector then allows the electric current to flow through whatever device the battery has been hooked up to so it is then powered.
Q: What is an "amp hour"?
A: The amp hour delineates how much capacity there is in a battery for energy to be stored. Or, in short, how much energy it can provide. It is often shortened to AH.
Q: How to calculate amp usage in an RV?
A: Sadly, this is not an easy thing to calculate when looking at how much amp usage you will need from your RV. You need to go around every single appliance that uses some sort of electricity that is powered by your deep cycle RV battery and figures out how many amps it uses per hour.
From there, you need to tot up how many amps all the appliances use together so you come to an answer that equals how many amps your RV would be using if it had all your appliances and electrical outlays on at the same time. Obviously, this isn’t always going to be the case, but by calculating your RV’s amp usage in this manner, you are calculating the amount that it will use in the worst case scenario.
Q: How long should an RV battery last?
A: This question is quite difficult to answer given that it totally depends on how much you use your RV. That being said, it is not unheard of for a 12-volt battery to last around 48 hours if RV owners use their battery power thoughtfully. This means not leaving the lights on all the time or having the heating on when no one is inside.
Q: Why does my RV battery smell like rotten eggs?
A: Even the best RV batteries can smell like rotten eggs sometimes. The reason being is that there is a shorted cell within it. This may have occurred due to battery fluids becoming too hot in a charger that was not suitable for your RV battery.
Q: What is Specific Gravity and how should I check it?
A: Specific gravity is also sometimes known as relative density. It is a way of measuring and gauging how dense or how heavy a liquid in when compared to water. It is a unitless measurement that is designated by a ratio. The temperature should also be kept in mind when checking specific gravity as this can change the density of liquids.
Specific gravity can be checked in several ways.
Using a hydrometer
- Pour some of the liquid you want to test into a beaker and ensure that a hydrometer is able to float freely in it.
- Check that your liquid is neither too hot or too cold to ensure that the calibrated hydrometer can take an accurate reading. This is often around 16 degrees Celsius.
- Put your hydrometer into the beaker of liquid and allow it to come to stand still.
- Take the reading from the hydrometer that is marked out at different places for different specific gravity. The reading will either be a ratio or a decimal number. If it reads 1.3 it means that the liquid you are testing is 1.3 times more dense as water at that temperature.
Using weight to determine specific gravity
- Weigh the liquid for which you want to know the specific gravity. To do so, weigh your beaker first and then weigh the beaker again once you have poured in a specific volume of your liquid. Then minus how much your beaker weighed.
- Follow the same steps with water using exactly the same volume of water to gauge the weight.
- Now calculate the ratio of the unknown liquid to water. This is your specific gravity measurement.
Q: How can I store batteries?
A: The best way to store your RV battery or you deep cycle marine battery is to dry it off and place it in a dry, cool spot in your house or garage that is well ventilated. You need to ensure that the temperatures of where you choose don’t go below freezing. If for some reason, your battery does freeze, it is imperative that you do not try to charge it as it could explode.
Any temperature between 0 and 27 degrees Celsius, of 32 degrees Fahrenheit and 80 degrees Fahrenheit should be fine.
Our Top Pick
Without a doubt, our top pick is the Universal UB1121000-45978. It is a 12-volt battery that can hold 100 AH making it able to answer a great deal of demands asked of it by RV owners. Helpfully, it is maintenance free as it is designed with the latest AGM technology that makes it a spill proof battery that is able to keep a hold of all the electrolyte it is first designed with. Additionally, not only is it rechargeable it can be mounted into any position so that it can be put wherever there is space - this is great to know given that it is a 12-volt battery so it is larger than the 6-volt golf cart variety. On top of all this, it is resistant to vibrations and shocks so that users will not see a drop out in their connection if their RV is going over some tough terrain.
Plus it comes at an affordable price point alongside a one year warranty that should put all RV owner worries aside. They should not have any worries however as we believe it to be the best RV deep cycle battery that money can buy.
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