Somehow you have found yourself looking for a deep cycle battery but you not sure which one to get. Technical jargon has never been your forte but still, you want to get the best deep cycle battery. This article will answer the question: what is a deep cycle battery? It will give you a list of the best deep cycle batteries on the market, and explain how to charge and maintain your battery once you’ve bought it.
What it a deep cycle battery?
A deep cycle battery is a battery that is repeatedly deeply discharged from the majority of its capacity to deliver steady power over a long period of time. These batteries differ from car batteries, or starting batteries, in multiple ways. For one, an automobile battery will produce a powerful surge of energy for a few seconds and then the alternator takes over while a deep cycle battery will give a steady stream of energy. The second difference is that automotive batteries will discharge a small amount of their capacity but a deep cycle battery can regularly discharge a majority of its capacity without damaging itself.
There are multiple applications for a deep cycle battery from boats to standby systems to even recreational vehicles (RV) and more. This article will give deep cycle battery reviews for three applications, namely RVs, solar power systems, and marine.
Best Deep Cycle Battery Reviews
Best RV Deep Cycle Batteries
XS-Power-D3100: High Energy Density
The battery model is an excellent deep cycle battery for RV with 1360 cranking amps and 110 amp-hours of discharge capacity. These batteries are constructed with an absorbed glass mat (AGM) design that prevents hazardous leaks while providing high energy density to ensure a powerful battery. This battery on sealed using a reinforced ABS plastic that makes in resist extreme heat as well as intense vibrations. This makes the XS-Power D3100 a simple solution that performs well in a hatch area or trunk. This battery can also be used for high-end audio systems that require 4000 – 5000W. The main issues of this battery are its hefty weight and price otherwise this is the best RV deep cycle battery.
- Three-year warranty
- Mountable in any position
- Resists vibrations and high temperatures
- No maintenance
- Reserve capacity of 237 minutes
- Very heavy battery
Battle Born 100 Ah: Safe and Reliable
This is perhaps the best RV deep cycle battery. The Battle Born 100Ah is an American product made with Lithium Iron Phosphate (LiFePO4). This battery delivers a lifetime capacity of 300 000 Amp-hours and between 3000 – 5000 charge/discharge cycles. It can charge to 99% in less than 3 hours and can even be charged with lead-acid battery chargers. This lithium-ion technology makes the Battle Born incredibly reliable and safe. Lithium-ion batteries are better for the environment than the usual lead-acid batteries. Plus, they last longer and outclass all other batteries. They are very light, weighing 29 pounds and they don’t require any extra hardware to install. In addition to RVs, this battery is excellent for trailers, golf carts, boats, and off-grid systems. But don’t think these are cheap deep cycle batteries. Like most other things, the latest technology is always very pricey and the Battle Born has a serious price tag.
- Ten-year warranty
- Long battery life with 3000 – 5000 cycles
- Maintenance free
- Mountable in any position
- Energy efficient and super quick charging
- Very expensive
Odyssey PC680: Excellent Multitasker
The battery sports a durable design that incorporates the spill proof AGM (absorbed glass mat) that shields the battery from shock and intense vibrations. The PC680 is a good multitasker deep cycle battery that provides an intense starting power and decent deep cycling. This Odyssey battery produces cranking pulse of over 2250 amps for 5 seconds, multiple times larger than conventional batteries. Odyssey’s battery can stay up to 2 years unconnected without charging but if you do charge it, it is quite quick. Charging to 100% takes only 4 – 7 hours. However, it has a low cranking rating and reserve capacity, especially compared to the rest of the options on the list. It is that it is a small deep cycle battery that is a moderate performer at a low price. The battery is only 15 lbs and compact compared to its competitors.
- Affordable battery
- Fast recharging rate of 100% in 4-7 hours
- Long cycle life up to 400 cycles
- Leak-proof and maintenance free
- Extreme temperature and vibration resistance
- Low CCA rating
- Low reserve capacity with 24 minutes
- Power of the battery significantly drops in a short amount of time
Renogy 50 AH: Small but Powerful
This deep cell battery from Renogy uses lithium-iron phosphate technology to provide a powerful solution in a small package. The battery is much lighter than other lead-acid batteries of 50Ah, weighing just under 15 lbs. If you value deep cycle battery life then this battery is for you. This small battery can produce thousands of cycles thanks to the built-in protection system. Plus, it is a low self-discharge of less than 3% every month which means you have a very good storage device. It is a robust device that is both fire resistant and explosion proof and can still operate in a wide range of temperatures. This is a premium product, so be prepared to fork out a lot. But the thing is you get a lot for a lot. The Renogy battery has minimal maintenance, fast charging, and lasts much longer than the ordinary lead-acid battery.
- Good battery life with over 2000 cycles
- Very safe and low Maintenance
- Energy efficient and super quick charging
- Very expensive
Best Solar Deep Cycle Batteries
Mighty Max Battery 12V 100AH: Off-grid Solar Design
This Mighty Max battery uses AGM and valve regulated design to give a great product that provides long service life and good performance with little maintenance. What makes these solar deep cycle batteries stand out from the rest is that they are specifically designed for off-grid solar. You will not need to worry about fluids or where to mount these batteries since they are spill proof thanks to the AGM. But the battery is quite heavy at 64 lbs. It’s not as big as other batteries, but it’s not very compact. On top of that, there are no mounting accessories that come with the battery. There is a warranty though only for one year, which seems a bit short when all things are considered.
- Can be used indoors and outdoors
- Mounting flexibility
- No maintenance
- Low-priced deep cycle batteries
- Doesn’t come with mounting hardware
- If left idle, some batteries may not hold a charge
WindyNation BattaMax: Strong Resistance
When you’re looking for the best deep cycle battery for solar, the BattaMax must be considered since it is designed for off-grid systems. First, the battery delivers power with a low self-discharge rate every month. Second, it is spill proof and subsequently able to be mounted in multiple positions. The BattaMax has a thick plastic exterior that resists shock, vibrations, and even acids. This is the main reason it has a life expectancy of 3 – 5 years. With the depth of discharge, you can expect 200 – 1200 cycles depending on whether you fully discharge or only discharge about 30%. This battery is backed by a, rather short, full 1-year warranty. And the other nice thing about this product is its price. WindyNation’s battery is one of the cheapest deep cycle batteries on the market and yet you get all this.
- A good number of discharge cycles
- Durable and robust build
- No maintenance
- Powerful battery with 240 min reserve capacity
- Heavy battery at 64 lbs
- Short warranty
Renogy Deep Cycle AGM: Reliable Budget Model
This is not a lightweight deep cycle battery, but if you are on a budget then this could be an option for you. For a 100Ah deep cycle marine battery the Renogy is in the sweet spot of not too expensive yet not cheap either. This battery uses absorbed glass mat technology to ensure no spills and leaks, making it maintenance free and mountable in multiple positions. If you choose this battery, you will see that this is a very efficient solar battery, converting 21%-24% of solar power to energy. The battery also has 600 cycles at a 50% depth of discharge (DOD) rating.
- Maintenance free
- Mount it in any position
- 2-year warranty
- Not the cheapest option
- Quite a heavy battery
- Reported to take several days to charge
Vmaxtanks SLR125: Long Battery Life
This company expects the SLR125 to last a whopping 8 to 10 years. First, the battery military grade plates and a rugged exterior. Next, it uses an AGM design that not only provides reliable starts but also makes the battery spill-proof. You can also count on the SLR125 to hold its charge when left unused since it only discharges at 3% per month. It has fast recharging which makes it a great choice for solar, wind, and emergency power backup systems. You won’t have to worry about any hazardous fumes or gases since the battery does not vent. Though you will need to vent the battery to prevent an explosion. The battery is 75 lbs which is a lot and an important consideration to where you will store it.
- Long life span
- Mountable in any position
- A great option for RVs too
- Reliable battery with excellent quality
- Poor construction of the handle
Best Marine Deep Cycle Batteries
VMAX MR127: Electrolyte Suspension Support
This is one of the best deep cycle marine batteries meeting the trifecta of performance, price, and value. While the battery is a little more expensive than most it is value for money when you learn that the battery has 200 minutes of reserve capacity and a 100Ah capacity. The MR127 is an exception deep cycle battery because it uses an electrolyte suspension system. This is also why it is reliable and lasts long. It is very durable due to a thick plastic casing that shields it from wear and tear while also resisting vibrations. While the thick casing serves a purpose, you have to keep in mind that it is why the battery weighs a substantial 67 lbs. With a capacity of 100Ah, this deep cycle battery can supply enough power for large motors, RVs and renewable energy systems like solar and wind.
- Fast charging time
- Mountable in multiple positions
- Reliable use
- Heavy battery
- Costs more than most batteries
Interstate Batteries DCM0035: Small and Affordable
This battery is very easy to mount and transport. It is only 23 lbs and pretty compact which is perfect for small motors for several hours of normal use. But it doesn’t have the same capacity as its heavier competitors. The DCM0035 only has a capacity of 35Ah, which is too little for certain applications. The battery uses AGM technology and so you know it is maintenance free, spill proof and can withstand vibrations. This makes it possible to mount the battery in almost any position. The small deep cycle battery is from Group U1 or GT9L and despite its size, it has a thick durable plastic casing that prevents major damage to the battery. If you are on a budget, this is a good option for you. The DCM0035 is way cheaper than 100Ah batteries so if you need a need enough power for small equipment then this is the right battery for the job.
- Cheap deep cycle batteries
- Light and compact
- Fast charging
- Low capacity of 35Ah
- After a year of use, they don’t easily hold a charge
- Long term damage caused by overcharging
ExpertPower EXP1233: Compact Versatile Model
This is a lightweight deep cycle boat battery that is an excellent option for applications that don’t need that much power. The 33Ah rating can give a user between 10 – 17 hours of use from a single charge, which is quite impressive. This battery is not just light but compact and you can easily install it into most spaces. It uses AGM valve regulated technology to make it a versatile battery that can be used both outside and inside.
- Inexpensive battery
- Only 23 lbs
- Long use from a single charge
- Indoor and outdoor use
- Not an option for intensive applications
- The low rating of 33Ah
- Need to be careful not to overcharge
Optima Batteries 8016-103: SpiralCell Technology
This battery has 750 cold cranking amps, 120 minutes of reserve capacity and 55Ah capacity, meaning it is powerful and consistent. It uses a technology called SpiralCell which are simply spiral-wound lead cells with a lead oxide coating. This design makes the battery more useable as you can recharge them more times more than other batteries. It is designed to withstand severe vibrations thanks to a casing that is several times more resistant than similar batteries. You also won’t have to stress about maintenance since the battery is spill-proof and it can be mounted almost anywhere. In short, this is potentially the best marine deep cycle battery for its price point.
- Reserve capacity of 120 minutes
- Can be recharged more times than regular batteries
- Two-year warranty
- Can be used as a starting battery
- Drain quickly
Maintaining a Deep Cycle Battery
Deep cycle battery maintenance is very important to know if you are going to own one. Even if a number of batteries say they are maintenance free, you will still have to do regular checks and interventions to maximise the life of your battery and its performance. Keep reading to find a list of useful hacks to ensure your deep cycle batteries you several years.
- Charge new batteries
- Clean dirt and debris
- Regularly check for bulges and cracks
- Check the fluid level
- Do not discharge below 80% capacity
- Always use batteries of the same size, age, and usage level
- Regularly test your batteries’ specific gravity and voltage
- Do not leave batteries inactive for several months
- Battery maintenance changes with age
- Use the right equipment to charge your batteries
Before you use your new deep cycle batteries you should charge them. Not all batteries are fully charged from the manufacturer. Also, since batteries lose charge with time and you do not know how long they sat in the store, it is imperative that you charge your battery before you use it.
Make sure you clean your batteries and ensure there is no dirt or debris that will build up on the battery terminals and hinder their effectiveness.
Physically inspect your battery if the are any cracks or if the battery has bulged out. Bulges and cracks indicate problems like freezing, lack of battery fluid or a problem with the alternator. The easiest way to prevent all this is to wipe the battery with a paper towel.
Deep cycle batteries should have their fluid level checked. They should be watered with distilled water after charging except if the plated were exposed before charging.
Shallow discharges should be made to prolong the life of your battery. Beyond 80% of discharge, sulfation speeds up and the deep cycle battery will work harder than it should. Ultimately, this will end up in a shorter battery lifespan.
If you are going to be using multiple batteries, you have to ensure that they are all of the same size, age, and usage level otherwise you will face some problems. If you replace one battery with a new one, the other older batteries will drain the newer one to their level since they cannot keep up with it.
It is crucial to measure your battery’s specific gravity and voltage to make sure it is operating correctly. If you need to test sealed batteries then you will need a load tester, otherwise, test your battery, you will only need a DC voltmeter and a hydrometer.
Batteries lose charge with time and so leaving them inactive for several months could result in them passing their threshold of discharge. Charge it at least once a month to keep the voltage up in warm weather, but in cold weather, you can go 2-3 months between charges.
You will have to change your battery maintenance routine with time. With time there is more use, wear and tear, and exposure to detrimental factors. And thus, older batteries will need more care and you will have to keep that in mind.
Ensure you use the right sized charging source for your battery. An over-sized charger will result in excess gassing, thermal runaway, and even explosions. However, an undersized charger won’t charge the battery no matter how long you charge it for.
Ways to Charge a Deep Cycle Battery Properly?
First, you need to know that after you have bought battery you will have to charge it. It is crucial that you know how to charge a deep cycle battery properly because you can literally cause an explosion if you don’t. Also, please use the right sized charger as mentioned above. Now follow the steps below:
- Only work in an area that is well ventilated since battery gasses may be released while you’re charging it.
- Wear protective gloves and eyewear so that there is no irritation to your skin or eyes.
- Connect the battery charger to the correct terminals, i.e. red clamp to “+” on the battery and black clamp to “-“on the battery.
- Next, plug the charger into the wall receptacle.
- If your charger is able to charge multiple types of batteries then select the option that matches your battery.
- Press start and leave the battery to charge. The charger will notify you with an indicator light when it is done.
- Turn off the charger, then disconnect the battery and use or store it as you feel fit.
How Long does a Deep Cycle Battery Last?
To determine how long a deep cycle battery lasts, you have to keep in mind several factors. You will have to consider the cell chemistry, depth of discharge, how you take care of the batteries when you’re not using them and if you leave them idle and for how long. All these and more culminate to your overall battery life. But with vigilant care, you can have your batteries for well over 5 years.