Adam holds a Bachelor's and a Master's degree in Linguistics, and creative writing has always been his greatest passion. For more than 25 years he's been working for several well-known automobile and travel magazines as an editor and expert consultant, but when Adam started his writing path here, at WisePick, it turned out that he's capable of writing practically anything about everything.
Initially being an engineering specialist, Tom has never stopped learning and acquiring other knowledge and skills. Now he’s involved in technical support for a well-known household appliances manufacturer, so no wonder he knows everything about almost everything you buy for your home.
Last updated: June 07, 2021
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Inn just one hour the sun radiates energy that the whole world can use in a year. That is free energy that billions of people on earth are missing out on, but now solar batteries are changing the game. While solar panels transform the sun’s energy into electric power to use in our homes, solar batteries store the tapped power for later use. That means you can store more free energy and buy less from the national grid, ultimately saving lots of money and reducing dependence from power suppliers.
The question is, which are the best solar batteries for your home? There are quite many of them on the market these days and they come in different types and sizes. You are probably familiar with the simplest 12v battery system used in vehicles and RV’s but this should only be an option for small household requirements. However, when looking for a battery system to power your entire house, you need to consider factors such as size, weight, battery type and amperage. That’s how we concluded that the Mighty Max Battery ML4D SLA with its 200Ah, maintenance-free battery and spill-proof design, is our best pick overall.
The products we’ve listed here we arrived at after pulling together a list of 20 best rated solar batteries on Amazon. We looked at reviews of each product to collect customer feedback and then consulted every known expert to determine what makes the best solar battery. And so we have a brief comparison table, in-depth reviews of our finalists and a detailed buying guide. We hope you will be able to make a purchasing decision by the end of this post.
If there is one solar battery that you can rely on to deliver power when you need it most, it has to be this Mighty Max Battery ML4D SLA. The battery has dimensions of 20.75’’ x 8.11’’ x 8.43’’ and comes with screws only, requiring you to purchase other accessories such as a harness and mounting equipment. As you would expect from an AGM battery, this one is maintenance free and features an advanced design for convenient use. No adding of fluid is required at all, unlike a flooded wet cell. Wide operating temperatures combined with a spill proof construction also means you can use it with full confidence with zero chances of injury.
In terms of performance, this 12V battery is one of the most powerful and long-lasting batteries. Its thicker plates it allows to discharge deeper than ordinary batteries, meaning you can have fun and power much longer without the need to recharge the battery. It also resists corrosion better than non-deep cycle batteries, meaning your maintenance task is an easy undertaking.
There is no end to the number of applications this battery can power but just to mention a few include: power tools, motor boats, robots, remote control aircrafts, electric vehicles, golf carts, toys, access control devices, emergency lighting, security, and many more. Ideally any job that requires a 12V battery will be sorted by this battery.
Last but certainly not least, the ML4D utilizes Absorbent Glass Mat (AGM) technology with a low pressure venting system, allowing it to be used in indoor and enclosed areas without leaking.
Another great option to go with, the ExpertPower EXP121000 is an AGM battery that is built for several uses around the home and outdoors as well. These are but not limited to emergency lighting, UPS systems, underwater fish finders and cameras, game feeders, radio control, fire and security alarm, photographic equipment and small toys. The vast functionality of this battery owes to its Absorbed Mat technology that offers a longer service life. In addition, the 12V battery can survive extreme temperatures, both hot and cold.
The battery can be recharged in just 11 hours and has a very long lifespan, at least 3 years. Another thing you will love about this battery is that is fairly compact and is not going to take up too much space wherever you want it. It also benefits from a vibration-free body and maintenance-free design, requiring no fluid fill up.
What’s more? The fact that is a 12V 100Ah deep cycle battery means it can handle quite a huge charge and provide hours of power. We also like the hard shell of this battery, which is non-spillable and highly resistant to the elements. If you have to carry it to somewhere, the 64-pound weight should be manageable and you will appreciate the inclusion of a carry strap for lifting. This product also has UL, CE, DOT, and ISO Certifications, therefore, it has been proven safe and reliable to use in homes and outdoors.
What makes it stand out?
Uses AGM technology for high performance.
Wide operational temperature, allowing it survive in extremely hot or cold conditions.
The Vmaxtanks SLR125 is another Absorbed Glass Mat deep cycle battery with a capacity of 125Ah. It is built tough, maintenance-free and has a 10-year lifespan, which sounds like a lifetime. This one is perfect for a various applications indoors and outdoors including emergency lighting, RV, toys, robots, camera and photography equipment.
Made out of military custom-made plates with robust tin alloy grids, the SLR125 has a slight margin of performance over some models. You can an average of 300 cycles with a 100% discharge depth or over 3,500 cycles with a 10% depth of discharge. A sealed construction ensures non-spill, leak-proof operation in any position without the loss of service life, while a valve regulator reduces gas accumulation inside the battery, yet it has 99% recombination capabilities.
This SLR125 also benefits from a low discharge rate of just 1 – 2% per month at room temperature, meaning it can be left idle for some time and still be able to provide lots of power when you decide to use it in the future. It certainly outperforms many AGM batteries.
It does have a wide temperature range from -4°F to 140°F, allowing it to be functional in chilly cold or very hot conditions. That range is for discharging, with the operational range when charging being from 14°F to 140°F. Let’s not forget the primary benefit of AGM technology, which lies in the battery’s ability to withstand vibrations. When it comes to charging, any quality AGM charger will suffice. There is also a clever strap built into the casing for when you will need to lift it up. Overall, this battery is a decent choice for RV.
Why did it make our list?
Military grade custom made plates.
Long service life – up to 10 years.
No dangerous fumes or gases accumulating inside.
Sealed body for leak-proof operation.
Broad temperature range.
Very low discharge rate per month.
What is not ideal about it?
May need venting to prevent build-up of explosive gases.
Dropping the voltage below 80% can affect its lifespan.
The Renogy RNG-BATT-LFP-12-170-BC is our choice for a Li-Ion model. However, this one comes at a seriously hefty price but it lasts 10x longer than an ordinary wet lead-acid deep cycle battery. It also benefits from fast charging, maintenance-free operation and reduced weight at just 46.3lbs, a fraction of what the other models on this list weigh.
This Renogy is a 12V 170Ah deep cycle battery with an integrated battery management system. This not only protects the battery for thousands of cycles but also keeps it running at peak performance. In addition, the cell features overcharge and over-discharge protection plus short circuit protection as well as a built-in cell fuse, making it a truly plug ‘n’ play. The robust construction features an explosion-proof stainless steel battery case and fire retardant additives.
Even with regular 100% depth of discharge, you can still make use of the full capacity of this battery without destroying it. The operating temperature for discharge is -4°F to 140°F, while the ideal discharge temperature ranges from 32°F to 113°F. This cell is also compatible with a variety of charge smart chargers and charge controllers, thus you should find it convenient to charge.
The compact build combined with the low weight of this battery make it perfect for building a power bank with multiple batteries in parallel. It also makes a great replacement for old flooded, AGM batteries. If you can match up the price of this Lithium Ion battery, it is certainly the very best in its class.
Why is it special?
Lasts 10x longer than regular lead-acid models.
Wide temperature range for both charging and discharge.
When it comes to establishing a home off-grid with flooded batteries, the Trojan J305E-AC is one of the best solar batteries available on the market. This battery is the best choice if you want to run large appliances such as air conditioners and refrigerators. Trojan batteries pass through rigorous tests to ensure that users will never experience problems and this one is a good example. Its terminals are corrosion-resistant and the reservoir is quite large that it will hold its charge for many years to come.
The thing with flooded batteries is that they do require regular maintenance, though the task is easy to do. On the other side, this battery is meant to last at least 10 years and that’s where the real value lies. It is also backed with a 4-year warranty for peace of mind. In addition, the battery can operate in extreme conditions such as high or low temperatures, remote areas and other challenging situations.
This Trojan is a 6V 339Ah that will provide excellent power to any large household appliance. You can expect up to 100 hours from one full charge. The battery measures 12.3’’ x 6.8’’ x 14.4’’ and weighs 83 lbs. On top of long-lasting performance, the J305E-AC is a great option for anyone on a budget. It happens to be the cheapest in this post, yet a reliable off-grid solar power system.
What makes it stand out?
Operates in extreme conditions.
Runs large appliances.
Pretty much affordable.
Which disadvantages must you keep in mind?
Regular maintenance is a must.
Things to Consider
Why to choose solar battery as your energy source
With over 1 million people in the US enjoying the use of solar energy, it is only a short time before the rest of the world catches up. There are many benefits to owning a solar battery. These reasons include but are not limited to:
Solar batteries power your home even during blackouts that may render others helpless. All you have to ensure is that you make use of the sunlight and fill your batteries.
Allows you to make the most of what nature provides. Instead of releasing the energy back to the grid, you can store it for later use.
Gives you control over the amount of electricity you use at night. By using the stored energy you can save money on your energy bills.
Sometimes spikes in energy prices are unavoidable due to different factors. By using solar power you can avoid these spikes and save money that can be used on other things.
The world is embracing clean energy and we must try our best to do so. By using renewable energy we reduce our carbon footprint and its effects on the planet.
There is no limit as to the number of batteries you can buy therefore you can always prepare for a stormy day.
Solar batteries are portable and thus can be moved from one location to another easily. You can transition between your properties or charge appliances with them.
Solar batteries types
There are quite a number of solar battery types that you can access in the market. All of these types come with different advantages are pitfalls. These battery types include:
Lead acid batteries
These batteries have been used for the past 15 decades and they have proven to be effective. They are not expensive and they can be recycled when they reach the end of their journey. These lead acid batteries are divided into flooded and sealed batteries.
Flooded batteries, such as the Trojan J305E-AC, work by submerging the cells into water for them to work. These types of batteries are submerged in water and therefore corrosion is unavoidable and maintenance is needed. One will have to check the levels of water regularly to ensure the panels are submerged under enough water. The area of storage needs to be well ventilated as these units do produce gas.
Sealed acid batteries possess capabilities such as they don’t lose charge when they sit idle. They are also the best when you are away most of the time and you cannot be hands-on with the system. These batteries are safe and they are spill-proof therefore you can be sure that they are in good condition. You can select whether to pick the absorbent mat type or the gel sealed acid batteries.
Lithium batteries are all the rage in the market. After making their debut in the market back in the 1970’s, these batteries became well known for their long life span, low maintenance nature, excellent recharge and high discharge rate. These benefits don’t come cheap though, as we have seen with the Renogy RNG-BATT-LFP-12-170-BC.
These are quite expensive and are hazardous to dispose of. There are brands that still use NiCad because of its non-freezing and low self- discharge abilities. They may not be the best in terms of efficiency but they can be a temporary measure.
Solar battery maintenance tips
Solar batteries are not entirely cheap and therefore you have to take care of them so that they can serve you for longer. Some valid maintenance tips include:
For flooded lead acid batteries corrosion is something to be worried about. Corrosion prevents the terminals from working properly and to be honest, it is an eye sore. Apply a sealant that hardens all around the wire lugs, nuts, terminals and bolts. Completely coating these parts will prevent the acid from corroding the metal.
Petroleum jelly makes a good sealant when you cannot afford the fancy sealants sold in the shops.
Exposed wires need to be sealed off to prevent any damage. This can be done with rubber spice tube or a heat-shrink tube.
Clean the battery tops with water to clean away acid splashes that cause corrosion. The units should be placed over a drainage while doing this to ensure that the water from the rinse flows away.
Avoid placing your batteries in extreme hot or cold areas as they will lose energy. It is recommended to place them in thermally sound structures.
Seek units that come with temperature compensators. These features adjust according to the temperature to ensure the batteries charge optimally.
Make use of low charge disconnects by using low voltage disconnect systems.
Let the batteries enjoy a state of full-charge to allow equalization. This is to be done every 2-3 weeks.
When it comes to solar batteries there is no cutting corners. You may find yourself spending a good chunk of your money. You can get a reliable unit ranging from $200 to a whopping $5000+ depending on the capacity of the battery. Consider the amount of power you need and make an informed decision.
Features to consider while buying the best solar batteries
Below are a few features that we believe you should consider before purchasing solar batteries.
Power and capacity
There are two factors to consider here. These factors include the amount of power it can store and how much power can be discharged. The amount of power that can be stored /discharged by the batteries is measured in Kwh (kilowatt hours). The manufacturer always provides this information therefore, you can compare with your power needs and purchase accordingly.
You have to consider how much voltage you need for your battery bank before installation. This is because it will be hard to alter the system once it is installed. If you do not need too much power, the standard 12V used in cars and boats will work well. If you need more power than that then you can consider getting 24V-48V systems. Getting a higher DC voltage results in lower costs as there are few modules to connect in one series.
DoD – depth of discharge
Depth of charge basically refers to the amount of charge available in the batteries for use. Usually all batteries reserve a fraction of the charge because of their chemical constitution. The higher the depth of charge the more power you have at your disposal to utilize. Many solar battery brands provide this information. For example, if a manufacturer presents a 10kw battery with a DoD of 90%, this means that you should not use up more than 9kwh before recharge. Following the manufacturer’s information prevents damage to the battery’s constitution.
Battery life cycle
The kind of batteries you install in your system should be able to serve you for 5-15 years, with the Vmaxtanks SLR125 being the longest lasting model among our finalists with a lifespan of 10 years. Before purchasing the batteries you should consider the environment’s temperature and battery quality. Lead acid batteries work well but they suffer from low discharges. Lithium batteries may work better in this field and thus may be more preferable.
Round trip efficiency
This refers to the overall energy that can utilized over the amount of energy used to store it. Usually relayed in percentages, the conclusion is the higher the round trip efficiency the more economical energy you get from the batteries. If you charge the batteries with 5kwh you can only use 4 out of the 5kwh which translates to 80% efficiency.
The battery size affects the amount of energy that can be stored. If you need plenty of energy then you should consider a larger unit while Simple power needs require a small unit. Consider the size of the area being covered and purchase accordingly.
Make sure that you dispose of old batteries in an environmentally safe manner. If there are parts that can be replaced, replace them instead of throwing the battery away. In many cases it is the metallic parts that may need replacement after facing corrosion.
The warranty is the manufacturer’s way of guaranteeing that your battery works as designed and it will keep working for a number of years before any performance drop. The warranty will vary in length depending on the brand that you purchase. If you experience any mishaps, the manufacturer is liable for solutions.
To calculate the power used over time requires the multiplication of power consumption by the running hours. For example, a 20W appliance running for 2hrs will take 40W from the battery. Do all this for all you’re your appliances and sum them up. If they take up more power than the expected battery size then you need a bigger size.
Yes, even the batteries with the longer lifespan will require replacement at a certain time as they r performance. Depending on the battery type you may need to replace them annually or after every two years.
The negative/ positive charges of the solar panel are connected to the corresponding charge controller. The charge controller in turn connects its negative/positive wires to the battery and voila!
There is no doubt that a solar battery is a great back-up plan for when there is a blackout or when you need to power appliances and electric devices off-grid. It also gives you the ability to store free energy coming from solar panels. Having reviewed the best solar batteries currently available, we believe you are now in a position to choose one that suits your needs.
Our top choice is the Mighty Max Battery ML4D SLA. We like the design and spill-proof construction, its low self-discharge rate, maintenance-free battery and a long service life. Above all, it definitely can run a wide range of appliances and tools.
Our second recommendation is the ExpertPower EXP121000. UL, CE, DOT and ISO certified, rest assured that you are purchasing a tried and tested model. It also boasts a short charging time, wide operational temperature and won’t be affected by the elements.
Lastly and if you are searching for a low-cost solar battery, the Trojan J305E-AC is your go-to product. A 10-year lifespan is unbelievable for the price of this battery, while you will be able to run both large and small electric tools.