Solar Battery Life: 5 Key Factors for Extended Use and Savings

Solar battery life depends on multiple factors, including the type, model, frequency of use, storage practices, maintenance, and depth of discharge. Everything considered, solar battery lifespan can range between five and fifteen years.

That said, there are some actions you can take to make your solar battery last longer. From proper installation to storage and maintenance, taking the right steps will help you maximize its efficiency and durability.

In this article, we’ll look into solar battery life expectancy more closely, detailing all the factors that affect it. Additionally, we’ll offer a few tips that can help you make the most out of your solar energy storage system.

How Long Do Solar Batteries Last: 5 Factors That Affect Solar Battery Life

Solar batteries typically last from five to fifteen years, which is shorter than the average 25-year solar panel lifespan. However, this can vary depending on the type or model of the battery, as well as the depth of discharge and various other factors.

Let’s analyze this in more detail to understand why some solar batteries last longer than others:

#1. Battery Type

Battery type, or its chemical composition, is one of the key factors determining its lifespan. For example, lead-acid batteries, the most affordable type, have a life expectancy of approximately five years.

However, they’re not as widely used as lithium-ion (Li-Ion) batteries, which make up the bulk of the modern residential solar battery market. These typically last between ten and fifteen years.

That said, there are certain differences between the two subtypes of lithium-ion batteries. According to a recent study conducted by the National Renewable Energy Laboratory (NREL), lithium iron phosphate (LFP) batteries are less affected by the depth of discharge and high temperatures than lithium nickel manganese cobalt (NMC) batteries.

In turn, high charge levels are less likely to impact the lifespan of NMC batteries than that of LFP batteries.

Here’s a summary of all the types’ traits:

#2. Frequency of Use

Solar battery lifespan depends on usage more than age—the more often you charge and discharge it, the shorter it will last. In other words, a solar battery’s ability to hold a charge decreases not so much with time but with use.

If you have an off-grid solar system, your battery charges during peak sun hours using excess solar power and discharges at night when there’s no sunlight to power your home. This daily cycling can take a toll on NMC batteries, but it won’t affect LFP batteries as much, as they tolerate greater depths of discharge.

#3. Storage Type

How you store your solar battery largely impacts its lifespan. If it’s exposed to the elements, it’ll deteriorate much faster than it would in a temperature-controlled environment. This is because both extreme heat and cold can degrade battery performance and shorten its lifespan over time.

For example, high temperatures accelerate chemical reactions in batteries, leading to faster wear and tear. On the other hand, low temperatures slow down electron movements, reducing the efficiency of chemical reactions—this way, a battery drains much more quickly than usual.

That said, the temperature tolerance of a battery varies based on its type. Lead-acid batteries are more sensitive to both heat and cold than lithium-ion ones. For this reason, they should be kept at around 40 to 80 degrees F.

Meanwhile, lithium-ion batteries can handle a temperature range of 0 to 140 degrees F. Still, it’s noteworthy that LFP batteries withstand both high and low temperatures better than NMC ones.

#4. Battery Maintenance and Care

Solar batteries are generally low-maintenance, meaning there’s not much you need to do to keep them functioning properly. That is, unless you notice a problem with your battery’s performance or appearance, in which case you should have an expert inspect it and handle any necessary repairs.

In fact, you might want to consider a maintenance plan for routine professional checkups, even if there are no apparent issues. Keep in mind that dust and debris can damage a battery’s health, just like they can affect solar panels’ performance. For this reason, it’s important to keep the battery’s surroundings and any exposed components clean.

#5. Battery Model and Brand

Solar battery model and brand also influence its lifespan, though to a lesser extent than temperature, usage, and chemical composition. Namely, a higher upfront cost and a reputable brand are usually associated with a longer solar battery warranty, which can indicate better quality and enhanced performance.

In most cases, a long warranty is a sign the manufacturer is confident in their product. It also often means the battery was built using advanced technology and high-quality materials, which translates to better performance and fewer issues down the line.

How to Maximize Solar Battery Life: 5 Pro Tips

Proper installation and optimal charging and discharging practices are some of the ways you can maximize solar battery life.

Let’s look into each of them more closely:

#1. Proper Installation

Proper installation is key for extending solar battery life and making the most out of your photovoltaic system. As previously mentioned, exposing your solar battery to extreme heat or cold will shorten its lifespan, so you need to store it in a temperature-controlled environment, such as a well-ventilated basement or garage.

The storage area must be dry to protect the battery, its wiring, and the connections to the solar inverter and panels from water-related damage. This is because moisture can interfere with the flow of electricity and increase the risk of short circuits on top of corroding battery components.

#2. Maintenance

While solar batteries don’t require much hands-on work in terms of maintenance, that doesn’t mean they don’t need any attention. In addition to keeping the area around your battery clean, you should monitor its performance to make sure there are no drops in efficiency or charge capacity.

Luckily, most modern solar batteries come with apps that allow for remote data tracking. This way, you can keep an eye on your battery’s charging speed, past and current charge levels, as well as energy production and consumption from your computer or mobile device.

With time, you’ll learn to recognize normal operating patterns so that you can notice any issues before they turn into major problems.

#3. Optimal Charging and Discharging Practices

Charging and discharging practices can either shorten or prolong solar battery life, so it’s important to follow the manufacturer’s guidelines for the state of charge and depth of discharge.

1. State of charge (SOC) helps determine how full or empty your battery is. If the battery is at 100% SOC, that means it’s fully charged; in contrast, if it’s at 0% SOC, it’s empty.
   
2. Depth of discharge (DOD) is the opposite of SOC. Simply put, it’s the amount of the battery’s power that’s been discharged. For example, if your battery is at 60% SOC, the DOD is 40%.

In general, it’s best to keep the charge level between 20% and 80%. This applies to deep-cycle batteries as well, even though they’re designed to handle repeated charging and discharging. Letting the charge level drop below the recommended DOD level too often can wear out your battery much faster, and so can overcharging.

#4. Charge Controller

A charge controller is an important tool for maximizing solar battery life, as it prevents overcharging and undercharging. Without it, solar panels can send too much or too little power to the battery, charging it above the SOC level or draining it below the DOD level. As previously mentioned, both can speed up wear and tear, thereby shortening solar battery life.

By balancing the power flow, the charge controller keeps the battery in its ideal charge range, helping it perform better and last longer. It also prevents extreme fluctuations in voltage, preserving battery health.

#5. Healthy Number of Cycles

As previously mentioned, the more cycles a battery goes through, the shorter it will last. Whenever you charge it or use the energy it’s stored during the peak sun hours, it counts as a cycle.

As a general rule of thumb, you shouldn’t run more than one cycle per day. However, if you have a smart export tariff selling excess solar energy back to the grid at a higher rate, you’ll profit more with two daily cycles.

That said, running more than two cycles per day may not only shorten your solar battery life but also lead to long-term problems due to premature wear and tear.

Solar Battery Efficiency and Performance Over Time

Solar battery efficiency and performance decrease over time, which means your battery’s ability to store and deliver energy will decrease as it ages. This happens due to a number of factors, including charging cycles and chemical wear. In general, a battery with a warranty of ten to fifteen years will lose about 20% of its capacity over that time.

These are the signs of a deteriorating battery:

• It takes a long time to charge and discharges more quickly than it used to.
• Your computer and mobile devices charge slowly, indicating a drop in the battery’s output.
• The battery is corroding, leaking, or showing other visible signs of wear and tear.

Now, let’s see how you can extend an aging battery’s performance:

• Reduce the load on it, especially at times when you use the most electricity.
• Replace the components of your solar system, such as the solar generator and wiring, that are worn out.
• Try equalizing and reconditioning to balance the charge between the cells and restore some of the battery’s capacity.

How to Choose the Best Solar Battery for Your Needs

To choose the best solar battery for your needs, you need to consider the following factors:

• Capacity. This is the amount of power a battery can store. You can use a solar battery calculator to determine the capacity you need based on your usage and the amount of electricity your system produces.
• Depth of discharge (DOD). The higher the recommended DOD level, the more of the battery’s power you can use without damaging it. Therefore, aim for a high DOD (80% or 90%) to make the most out of your energy storage.
• Cycle life. This is the number of charge cycles you can run before the battery’s capacity starts dropping. The higher the number, the longer your battery will last.
• Cost. Solar battery prices vary depending on their quality, which means that a higher price usually indicates better features.
• Size and space. Some batteries are smaller, while others need more room. Naturally, you should make a choice based on how much storage space you have.
• Brand reputation. A reputable brand means a reliable product, a long warranty, and good customer service. Browse through the Portable Sun selection of batteries to find options from trusted manufacturers known for quality and excellent support.

Final Thoughts

Solar battery life depends on various factors, from its type and model to usage and maintenance practices. While its lifecycle is bound to come to an end after a certain number of years, you can definitely take some steps to prolong it and get the most out of your solar energy storage.

Starting with proper installation and following the manufacturer’s recommendations for charging cycles, you’ll see the results of your care and enjoy clean, renewable energy for a long time.

Solar Battery Life FAQ

#1. How long will a 10kWh battery last?

How long a 10kWh battery will last depends on many factors, including its type, usage, and temperature. On average, most solar batteries last ten to fifteen years with proper maintenance and care.

#2. Can a lithium battery last 20 years?

A lithium battery can last 20 years under ideal conditions, although its lifespan usually ranges between 10 and 15 years. However, the solar battery time (how long it takes to discharge) will decrease as it ages.

#3. How to know when to replace a solar battery?

To know when to replace a solar battery, you should monitor its performance over time. If there’s a noticeable drop in capacity or problems with charging, it may be time for a replacement.

Disclaimer: The content on Portable Sun is for informational purposes only. Electrical work can be dangerous—always consult a qualified professional. We are not liable for any injuries, damages, or losses from installation or use. Always follow local regulations and safety guidelines when handling electrical components.