How Long Do Solar Panel Batteries Last? The Answer Revealed

Solar batteries allow you to make the most of the energy from your solar panels. A battery stores excess energy generated by your panels, and you can use that energy to power your home when necessary. For example, stored energy is useful after dark, during power outages or during cloudier periods when your panels aren’t generating enough energy to power your home.

Without a solar panel battery bank, all the extra energy from your panels is sent to the grid and distributed to others. One of the most common questions people have about solar batteries is how long they last. Although there’s no specific number that answers the question, there’s a general lifespan range and several factors that impact battery longevity to consider.

What’s the Average Lifespan Range for a Solar Battery?

In most cases, solar batteries last between five and 15 years. Many solar panel systems last between 20 and 30 years, which means that you’ll likely need to replace your batteries at least once. A professional can tell you how many batteries you may need for your system.

How Do You Know When To Replace a Solar Battery?

Once a battery wears out, it’ll lose its ability to hold a charge. As the battery approaches the end of its useful life, you’ll probably notice that it holds less and less power. For example, you may notice that you no longer have enough power to last through the night.

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What Factors Affect the Life of a Solar Battery?

You can help maximize the useful life of your battery when you know what can potentially shorten its life. There are five key factors that affect the longevity of solar batteries.


Although some types of batteries require little maintenance, some require more. If you have a battery that requires professional inspection, you may expect to spend $150 or more each year. Maintenance helps prevent some problems. Even with maintenance, there may be issues that require repairs sometimes. Also, some other parts may need to be replaced. Depending on several factors, repair costs often vary between about $100 and $3,000. A professional can give you a more specific estimate range based on your needs.


There’s an ideal operating temperature for each solar battery, and you’ll usually find that information in the owner’s manual. Maintaining that temperature is important to both boost performance and protect the battery. Solar batteries must be kept in ideal locations. In areas with extreme outdoor temperatures, keeping solar batteries indoors is better. For example, most solar batteries perform well in Colorado during the colder months if they’re in well-insulated garages or in basements.


There are several types of solar batteries, and they have different chemical compositions. These are the main types and their features.

Lithium-Ion Solar Batteries

These batteries tend to have a longer lifespan than their competitors, which is one of the reasons why they’re the most popular choice. Lithium-ion batteries often last a decade or longer. They’re also smaller and weigh less. Due to increased demand and production in recent years, lithium-ion batteries dropped significantly in price from their original cost. Additionally, they require less maintenance than other types of solar batteries and don’t require as much charging as others.

Lead-Acid Solar Batteries

For several decades, these batteries have been key parts of off-grid energy system planning. Lead-acid batteries are inexpensive in comparison with other types. However, they have a shorter useful life. Although they can last longer, some may only last up to five years. In comparison with lithium-ion batteries, lead-acid batteries have a lower depth of discharge. This means that the power the battery releases in relation to its full capacity is lower. For example, a lithium-ion battery may have a DoD of 80% or higher, and a lead-acid battery may have a DoD of 50%. Their lower DoD and shorter lifespan are the key reasons lead-acid solar batteries aren’t as popular as lithium-ion batteries today.

Saltwater Solar Batteries

As their name suggests, saltwater batteries are powered by the electrolytes in saltwater. Since they don’t contain heavy metals like other types, these batteries are often preferable to people who are committed to using ecofriendly products. Saltwater batteries are easy to recycle. Some sources say these batteries can last 5,000 charging cycles or potentially longer.

Nickel-Cadmium Solar Batteries

If you’re looking for a commercial solar battery, this is a suitable option. Nickel-cadmium batteries aren’t used for residential systems. Utility companies and larger entities can benefit from these batteries. In large-scale applications, they tend to be durable enough to stand up to extreme temperatures well and have a longer lifespan.


How much a battery is used is one of the most influential factors in determining its longevity. The more you use and recharge the battery, the shorter its lifespan is. Popular solar batteries today are deep-cycle batteries. This means that they can handle long, frequent and deep charge and discharge cycles. However, they should not be drained completely each time. Using batteries beyond their maximum recommended DoD frequently can shorten their life. Use frequency can vary based on several factors as well. For example, a person using a solar battery with an off-grid system uses the battery more than a person with a grid-tied system.


Warranties show a manufacturer’s level of confidence about how long a battery may last. Although quality is a factor, the type of battery is a key factor that determines the length of a warranty. For instance, because lithium-ion batteries tend to last longer, the warranties for them tend to be longer. Many lithium-ion batteries have 10-year warranties. Alternately, warranties for lead-acid batteries aren’t as long since these batteries tend to have shorter lifespans.

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How To Maximize Solar Battery Lifespan

Now that you know the main factors that influence how long a solar battery lasts, it helps to know how to use solar batteries in a way that promotes longevity. These are some tips to accomplish that.

Keep Your Batteries Charged

If you have multiple batteries, don’t leave some on a shelf to store for long periods of time. Leaving them in storage without charging them for a long time can lead to damage and shorten their useful life.

Rotate Your Batteries

When you have several batteries that you use together, make sure to rotate them. This is because batteries can charge differently. For example, the batteries on the outside may charge better than the ones in the middle. If you rotate them evenly, they should also wear more evenly over time.

Charge Your Batteries Correctly

Undercharging and overcharging are both detrimental to solar batteries. Trying to keep batteries charged can seem confusing since there are different types. However, each manufacturer has specific charging instructions. You can also use a charge controller to prevent improper charging.

Limit Your Batteries

Many people prefer to use multiple batteries in an array. Although it may seem like more batteries will lead to more power, having too many batteries in your array may reduce their lifespan. With fewer batteries, there is less wear and less resistance. A professional can tell you the ideal number for your needs.

Use Larger Cables

To correctly connect a solar battery with the rest of the system, you’ll need interconnect cables. If you use larger ones, there’s less electrical resistance. Larger interconnect cables also help promote a longer lifespan by reducing wear on your battery. With cable size, you need the right AWG number for your system’s voltage, and you need the correct length for your needs.

Be Mindful of the DoD

Remember that using a battery past the listed DoD percentage can degrade it faster. Capacity is measured in kWh, which is kilowatt-hours. For example, if you have a battery with a capacity of 16 kWh and use 10 kWh when it’s fully charged, the DoD is about 63%. Imagine that the manufacturer lists a maximum DoD of 80%. If you had instead used 14 kWh of that battery’s full capacity, you would have exceeded the DoD.

Use the Right Batteries

To improve battery performance and longevity, it’s important to use the right type of battery or batteries for the application. For example, you need a battery with the right voltage rating for your specific needs if you want to maximize its useful life. A professional can analyze your home or commercial building to determine the right solar products and ideal batteries.

Follow Maintenance and Temperature Guidelines

After a professional determines where to put your solar batteries, be sure to maintain the temperature in that area in accordance with manufacturer recommendations. For example, if you go on a winter vacation and keep solar batteries in your garage, make sure there’s ample warmth to protect them. Also, be sure to follow professional recommendations for any maintenance on your batteries. Some batteries require regular cleaning, and some types require professional inspection periodically.

Final Thoughts

If you want to make the most of your solar energy, batteries can help you accomplish that. Impact Energy is here to answer any other questions you have about using solar batteries. If you have any further questions, feel free to reach out to us at (888) 240-1131 or email us at