Investing in solar panels sends you in the right direction toward energy independence, but installing a solar battery can take you there. A battery offers stored energy when you need it, such as during a power outage or when the sun clocks out for the day.
But what solar battery should you buy? This article explores our top six picks and why we chose them to help you select the best option for your home.
Need a solar company to install a battery in your home? Read our guide on the best solar companies to get a quote today.
4.4
Installs high-quality Maxeon panels
Outstanding customer support
Best-in-class warranty lasts 40 years
3.7
Affordable prices
Excellent selection of panels and services
Locations in 22 states
4.3
No payments needed for 18 months
Provides in-house financing
Offers top brands like LG and Trina
3.9
Highly rated customer service
Provides 24/7 panel monitoring
Solid A+ rating with the BBB
What Are the Best Solar Batteries?
The best solar batteries stand out for exceptional warranties, value, capacity, innovative smart technology and more. Here are our top picks in the solar industry:
What Should You Look for When Shopping for Solar Batteries?
Shopping for solar batteries is no easy feat. You’ll need to consider several factors to ensure you get one that meets your needs and expectations. Because solar batteries are expensive, it’s important to take the time to find the right fit. Here are a few top things to look for as you shop for solar energy storage:
Capacity: The capacity of a battery system is one of the most important factors to consider, as it will determine how much power you can save for later use. Battery storage is measured in kilowatt-hours (kWh). Ensure you choose a battery with a large enough capacity to meet your expectations. For example, if you want to go off the grid with solar power, you might need more than one battery to ensure you have plenty of stored power for when you need it.
Power rating: Each battery has a power rating, which tells you about the rate at which the battery discharges or releases stored energy. Batteries with higher power ratings can release energy faster, ensuring they keep up with higher energy demands.
Performance metrics: Pay attention to the performance metrics on each battery, as these will play a crucial role in your experience. For example, the battery’s depth of discharge (DoD) and round-trip efficiency are important metrics to look for. The depth of discharge refers to the amount of energy you can use before the battery needs recharging, and the round-trip efficiency is how much of the stored energy you can use as output energy. The higher these metrics are, the more you’ll be able to take advantage of the system’s capacity.
Note: If you’re looking for a solar generator (a mobile solar solution to power your electronic devices), see our review of best solar generators.
Compare the Top-Rated 6 Solar Batteries
Choosing the best home battery can be daunting. The table below outlines the basics of our top picks to help you narrow down the options for your home.
| Solar Battery | Price | Price Per Watt | Capacity in kilowatt-hours (kWh) | Continuous Power Rating in kilowatts (kW) | Warranty |
| Tesla Powerwall 2 | $9,000 – $13,000 | $1.55 – $2.24 | 13.5 | 5.8 | 10 years, 70% capacity guarantee |
| Sonnen Eco | $6,100 – $20,000 | $2.03 – $2.50 | 5 – 20 | 3 – 8 | 10 years, 70% capacity guarantee |
| Enphase IQ | $9,000 – $15,000 | $3.90 – $7.03 | 3.36 – 10.08 | 1.28 – 3.84 | 10 years, 70% capacity guarantee |
| SunPower SunVault | $12,000 – $28,000 | $1.76 – $3.5 | 12 – 24 | 6.8 – 8 | 10 years, 70% capacity guarantee |
| Generac PWRcell | $10,000 – $18,000 | $2.95 – $2.69 | 9 – 18 | 3.4 – 6.7 | 10 years |
| Panasonic EverVolt | $15,000 – $20,000 | $2.08 – $3.26 | 11.1 – 26.65 | 4.6 – 9.6 | 10 years, 60% capacity guarantee |
Tesla Powerwall 2
3.9
Our Rating
With an exceptional warranty, high round-trip efficiency, and a high depth of discharge, the Tesla Powerwall 2 earns our pick for the best overall battery. However, it only comes in one size. If you only need 5 kWh to power your home, you’ll have to pay for a larger battery than you need. On the other hand, if your home needs more power than the Powerwall 2 provides, you’ll need to get a second one, doubling your costs.
The Tesla Powerwall 2 offers perks, like integration into the Tesla app with custom controls. It’s compatible with new or existing systems or as a stand-alone backup power system, making it a sound option for homeowners with existing solar setups that want to try energy storage.
In addition, these batteries feature a high round-trip efficiency and depth of discharge, so customers get the most out of the battery’s capacity. They come with a quality warranty that doesn’t feature a cycle clause, so coverage doesn’t end before the 10-year warranty does.
The Tesla Powerwall 2 is sleek and efficient, and it pairs well with any solar system. You can even use it as a stand-alone home power backup (without using a solar power system). You can also daisy chain multiple Powerwalls together to expand energy storage as backup power for your home. For example, you can install 10 or more Powerwalls to generate backup power for a month or more, depending on your energy use. And through Tesla’s mobile app, you can toggle how and when to use the stored energy.
The one major drawback of the Tesla Powerwall 2 is its availability in only one size, which might be too large or too small for your home. The tesla battery is also more expensive than other brands — and this higher expense will compound if the size of your house requires more than one battery.
Tesla offers two primary battery options: the Powerwall 2 and the Powerwall+. The two batteries are nearly identical — the difference being the inverter. The Powerwall 2 is just a solar battery. The Powerwall+ features an integrated solar inverter with the battery.
Tesla sells these models to complement its solar roof and solar panel systems. Tesla designed the Powerwall 2 for an existing solar system. If you just need a power backup for your home, the Powerwall+ is the bet
| Solar Battery Model | Capacity (kWh) | Continuous Power Rating (kW) | Depth of Discharge (DoD) | Round-Trip Efficiency |
| Powerwall 2 | 13.5 | 5.8 | 100% | 90% |
| Powerwall+ | 13.5 | 5.8 | 100% | 90% |
Both of Tesla’s batteries come with a solid warranty, lasting 10 years. Unlike many battery manufacturers, Tesla doesn’t restrict its warranty with a cycle clause. Instead, the warranty comes with no throughput, unlimited cycles, and an end-of-warranty capacity of 70%.
You can only buy the Tesla Powerwall 2 directly from Tesla in select states. However, you can find the batteries through a list of Tesla-certified installers and solar companies, including ADT Solar, Palmetto Solar, and Sunrun.
Sonnen ECO
4.6
Our Rating
With multiple features, including the ability to customize and compatibility with or without solar, plus a good price, the Sonnen Eco is a great battery pick for value. However, it’s larger than other batteries on our list and has lower continuous power ratings.
Our reason for liking Sonnen Eco’s battery is its value for the price. The system is highly customizable. It comes in 2.5-kilowatt-hour increments, allowing you to pick in-between battery sizes that aren’t often available. Compared to other brands, Sonnen Eco has the most power capacity sizes, ensuring you get the right fit for your home. This lets homeowners not overpay for a system that’s too big for their home.
Sonnen Eco also has an alternating current (AC) battery, so you don’t necessarily need a solar panel system to use it. Instead, you could use it to harvest electricity when it costs the least and when power costs the most.
Sonnen’s solar batteries are larger than other models on our list. That can be a problem for homeowners with limited space, especially if you want to install more than one. In addition, these batteries show a lower continuous power rating than several other options on our list.
Sonnen sells batteries in seven sizes ranging from a 5-kWh system to 20-kWh system. The company makes each size with 2.5 kWh modules, so sizes jump by increments of 2.5.
| Solar Battery Model | Capacity (kWh) | Continuous Power Rating (kW) | Depth of Discharge (DoD) | Round-Trip Efficiency |
| Eco 5 | 5 | 3 | 90% | 90% |
| Eco 7.5 | 7.5 | 4 | 90% | 90% |
| Eco 10 | 10 | 8 | 90% | 90% |
| Eco 12.5 | 12.5 | 8 | 90% | 90% |
| Eco 15 | 15 | 8 | 90% | 90% |
| Eco 17.5 | 17.5 | 8 | 90% | 90% |
| Eco 20 | 20 | 8 | 90% | 90% |
Sonnen batteries come with a 10-year, 10,000-cycle warranty that guarantees an end-of-life capacity of 70%. The warranty ends when the battery reaches the 10-year mark or completes 10,000 cycles, whichever comes first.
Sonnen partners with various solar companies throughout the country, and the company vets each installation to ensure quality installations. You can find the full list of Sonnen’s solar partners on its website, which lists each installer option by state.
Enphase IQ
4.4
Our Rating
Packed with tech features to improve overall experience, the Enphase IQ battery is perfect for smart tech. Its system-monitoring features promote a seamless experience, even during power outages. However, these batteries are only compatible with Enphase microinverters, which can be a problem for homeowners with existing solar systems.
The Enphase IQ is aptly named. It has numerous smart features for an elevated experience. For example, it shows off an integrated high-tech Enphase inverter, well known in the industry as a quality product.
It also has monitoring technology — on par with Tesla’s — that switches between power modes to ensure homeowners get the most out of their battery. The monitoring tech automatically switches the battery into the correct power mode based on the situation, such as turning on during a power outage.
You can check the battery’s performance through a mobile app that gives you more visibility and control over systems than other solar batteries. The Enphase IQ is also compatible with gas and solar generators, making it a suitable pick for more home scenarios.
Enphase IQ batteries are only compatible with Enphase microinverters. This battery won’t work If your solar setup utilizes a different option. Also, extra warranty coverage comes at a higher cost.
Enphase IQ batteries come in four primary options: IQ 3, IQ 3T, IQ 10, and IQ 10T. These batteries feature integrated solar microinverter technology and AC coupling, making them an ideal fit for existing Enphase setups.
| Solar Battery Model | Capacity (kWh) | Continuous Power Rating (kW) | Depth of Discharge (DoD) | Round-Trip Efficiency |
| IQ 3 | 3.36 | 1.28 kW | 100% | 96% |
| IQ 3T | 3.36 | 1.28 kW | 100% | 96% |
| IQ 10 | 10.08 | 3.84 kW | 100% | 96% |
| IQ 10T | 10.08 | 3.84 kW | 100% | 96% |
Enphase offers a modest 10-year warranty with an end-of-warranty capacity of 70%. But it has a cycle clause of 4,000 cycles and a throughput clause, which measures the battery’s total lifetime energy generation.
The IQ 3 models feature a throughput clause of 9.8 megawatt-hours (MWh), whereas the IQ 10 models have a higher clause of 29.4 MWh. Your warranty will end if your battery produces this amount of energy before the 10-year mark.
The Enphase IQ battery is available through various chain solar companies, including ADT Solar and local installers. Enphase designates its certified installers as platinum, gold, and silver (ranked by numbers of installations completed) and presents options by location on its website.
SunPower SunVault
3.5
Our Rating
With an impressive 24 kWh capacity on its base model paired with an expansion battery, SunPower’s SunVault Storage solar batteries are an excellent choice for homeowners who need more energy storage. You might need just one battery to satisfy your energy needs because the SunVault battery is so large. But unlike other solar batteries, the SunVault is only compatible with SunPower’s solar setups.
The SunPower SunVault delivers the best battery capacity on our list, 24 kWh capacity and 8 kW of continuous power (when you combine the base model with the expansion model). If you were to choose many other brands on the market, you’d need to combine more than two batteries to achieve this capacity. Compared to other solar batteries like Tesla, the SunPower SunVault delivers higher total capacity at lower cost.
Given the superior capacity of these batteries, the SunVault battery is ideal for larger homes or homeowners who want to switch to off-grid living.
Unlike most battery manufacturers, SunPower doesn’t disclose depth of discharge information about its SunVault batteries. That makes it tricky to compare the battery to others. Also, these systems are only compatible with SunPower solar systems.
SunPower has two SunVault models to accommodate homeowners. including a base unit (the SunVault Base, rated at 12 kWh), and an energy expansion battery (the SunVault Energy Expansion, also rated at 12 kWh). The SunVault Energy Expansion is a secondary solar battery that you can use as a power expansion with the SunVault Base for a combined capacity of 24 kWh. The SunVault Base includes the Hub+, which includes the solar inverter and Wi-Fi module.
| Solar Battery Model | Capacity (kWh) | Continuous Power Rating (kW) | Depth of Discharge (DoD) | Round-Trip Efficiency |
| SunVault Base | 12 | 6.8 | N/A | 85% |
| SunVault Energy Expansion | 12 | 6.8 | N/A | 85% |
SunPower SunVault batteries have a standard 10-year warranty and a 70% end-of-warranty capacity guarantee. However, the warranty includes a 4,000-cycle clause for every model and varying throughput clauses based on the model. The SunVault Base has a 38 MWh throughput clause, and the SunVault Energy Expansion has a 76 MWh clause.
SunPower’s batteries, like its solar panels, are available exclusively through the company or authorized dealers. To buy a SunPower battery, you need to contact SunPower to find an authorized dealer.
Generac PWRcell
4.3
Our Rating
As a top choice among consumers, the Generac PWRcell is worth considering as a battery solution. This battery features high round-trip efficiency, customizable sizing, and protective features that promote durability. But the depth of discharge is lower than other batteries on our list, including Tesla and Sonnen.
The Generac PWRcell is a consumer favorite. It’s packed with features at a reasonable price. For example, customers can tailor their storage setup with the PWRcell, creating systems as large as 36 kWh of backup storage. Its batteries come in four sizes — 9, 12, 15, and 18 kWh. And you can daisy chain various battery sizes to get the exact capacity you want for your home. For example, if you need 26 kWh to power your entire home for 24 hours, you can buy 9 and 18 kWh PWRcells to get to 27 kWh.
These batteries feature one of the highest round-trip efficiencies on our list. As an added bonus, the protective battery cabinet provides extra durability for indoor and outdoor installations.
While higher-than-industry-standard of 80%, the depth of discharge percentage on these batteries is lower than other batteries on our list. These batteries also aren’t compatible with all existing solar setups. If you like them, ensure you verify compatibility before you buy.
The Generac PWRcell comes in multiple sizes to accommodate varying energy needs. Each system features 3 kWh battery modules, so system capacity increases in three increments. For even more battery capacity, you can install multiple PWRcell cabinets, increasing your energy storage up to 36 kWh.
| Solar Battery Model | Capacity (kWh) | Continuous Power Rating (kW) | Depth of Discharge (DoD) | Round-Trip Efficiency |
| PWRcell M3 | 9 | 3.4 | 84% | 96.5% |
| PWRcell M4 | 12 | 4.5 | 84% | 96.5% |
| PWRcell M5 | 15 | 5.6 | 84% | 96.5% |
| PWRcell M6 | 18 | 6.7 | 84% | 96.5% |
Generac’s 10-year solar battery warranty is comparable to many other manufacturers. Each battery comes with a throughput clause ranging from 22.6 MWh to 45.3 MWh based on the battery. The company doesn’t provide information about its end-of-warranty capacity guarantee — if there is one.
Generac PWRcells are widely available through various solar installation companies and Generac-certified partners. Its batteries are also available directly through the company’s website.
Panasonic EverVolt
4.1
Our Rating
If you’re hoping to transition to off grid living or have lofty energy demands, the Panasonic EverVolt is a wise pick. These batteries are modular and customizable. They let you add battery units to reach your desired system size. However, the end-of-warranty capacity guarantee (60%) is lower than that of competitors, including Tesla and Enphase.
The Panasonic EverVolt is a top contender on our list, particularly for homes with larger solar systems with higher energy demands or homeowners who want to transition to off-grid living. You can string together up to six batteries for 102 kWh of total storage, ample energy for homes of varying sizes. This is perfect for larger homes that use a lot of electricity and for homeowners worried about powering their house during lengthy power outages.
In addition, these batteries come in multiple options, including AC coupled and DC coupled. With AC-coupled systems, solar energy is converted to AC (alternating current) power then DC (direct current) power for storage in the solar battery. It’s then converted to AC again to power your home.
On the other hand, DC-coupled solar systems only have one conversion (converting DC from the battery to AC to power your home). Because each conversion has an efficiency loss, DC-coupled systems are more efficient.
Unfortunately, Panasonic doesn’t release depth of discharge information for its EverVolt batteries. This makes it tricky to compare options to ensure you get a good fit for your home. Also, its end-of-warranty capacity guarantee is lower than that of competitors.
Panasonic offers a handful of EverVolt models like many solar battery manufacturers, including two standard options and two plus configurations. AC-coupled and DC-coupled models are available, ensuring there’s something to accommodate both types of solar system setups.
| Solar Battery Model | Capacity (kWh) | Continuous Power Rating (kW) | Depth of Discharge (DoD) | Round-Trip Efficiency |
| EverVolt | 11.4 | 4.6 | N/A | 90% |
| EverVolt Plus | 17.1 | 5.5 | N/A | 90% |
| EverVolt 2.0 | 17.1 | 7.6 | N/A | 90% |
| EverVolt Plus | 26.65 | 9.6 | N/A | 90% |
The Panasonic EverVolt comes with a 10-year warranty, comparable to the industry standard. It features a 60% end-of-warranty capacity guarantee, lower than other options on this list. In addition, the throughput warranty varies between 30.2 MWh and 45.3 MWh based on the model.
Panasonic EverVolt batteries are widely available through various dealers. The company works with pre-approved installers, so you can find them through an extensive custom network of installers.
How Do Solar Batteries Work?
The purpose of solar batteries — storing excess energy — is a simple concept. But how does it happen? It starts on your roof or wherever your solar panels are. When sunlight hits the solar array, panels convert visible light into an electrical current.
The DC power that the system produces will either remain as DC power or get converted to AC power, depending on your home’s setup. Your solar array’s power generally goes straight to your home to power everything in it.
One of two things happens when the system produces more energy than your home needs. If you don’t have a battery, the energy will flow back to the grid, a process called net metering. With a battery, the process looks different.
Instead of going to the grid, extra energy from your solar array flows into the battery and charges it. The rate at which the battery charges depends on the amount of extra energy produced, current electricity demands, and the size of the system.
In the end, the energy is in the battery. When night falls and your solar array stops producing energy, you’ll pull from the grid or use the energy stored in your battery. Or perhaps there’s a power outage, and you need this reserve power to keep your home running until power gets restored. This is where your battery comes in. When your home needs power, the system will discharge to supply it.
You can also use the energy from your solar battery during peak power times, which stresses the grid (find out what grid stress entails), and when some utilities charge more for power).
Wondering how solar batteries work? This video explains the technology in depth.
Are There Different Types of Solar Batteries?
Solar batteries come in four main types:
- Lead acid
- Lithium-ion
- Flow
- Nickel-cadmium
Each option has its perks and drawbacks, so some options are better for specific scenarios than others.
Lead Acid
Lead-acid batteries work by creating a charge differential between lead and sulphuric acid. This battery is the oldest on the scene and comes in two separate types: sealed and flooded. The sealed lead acid batteries feature a unique design that reduces toxic gas release into the atmosphere.
The second type, a flooded lead acid battery, is similar to traditional car batteries but bigger. Both types have a shorter lifespan and depth of discharge than other options (lithium-ion, flow, and nickel-cadmium) and require more regular maintenance. Because of this, they’re usually the cheapest of the bunch. But today, they’re no longer popular among solar companies.
Lead-acid batteries are for homeowners that want to create a DIY solar energy storage system with car batteries.
Lithium-Ion
Lithium-ion batteries are the most common type of battery in today’s solar market. Like all batteries, they use an anode and cathode to create and hold a charge between lithium ions. These batteries are relatively new compared to lead-acid batteries and are a staple in residential settings. Their popularity stems from a few key benefits of lithium-ion batteries, including a longer lifespan, less required maintenance, and a lighter design than lead-acid batteries.
They also feature a higher depth of discharge, which translates to a better usable capacity. However, there’s a risk of thermal runaway with these batteries, which means they can catch fire if installed improperly.
Lithium-ion is the technology behind all the solar batteries on the market today.
Flow
Flow batteries use the flow of two liquids with different additives to create an ion exchange and store an electric current. These batteries are another new solution in the solar battery game, so there’s room for improvement. They have a lower storage capacity than other battery options, and no solar batteries on the market use this newer technology. However, they have a few impressive features.
For example, they have 100% depth of discharge, meaning you can use the entire stored energy. They’re also water-based, so they’re nontoxic.
Nickel Cadmium
The fourth type are nickel-cadmium batteries, also known as Ni-Cd or nickel batteries. These batteries have been around for a while and can operate at extremely high temperatures compared to other battery management systems. That makes them popular in commercial settings.
However, they’re highly toxic, and they’re banned in numerous countries. Currently, no solar battery uses nickel-cadmium technology as lithium-ion has battery storage capacities and safety.
4.4
Installs high-quality Maxeon panels
Outstanding customer support
Best-in-class warranty lasts 40 years
3.7
Affordable prices
Excellent selection of panels and services
Locations in 22 states
4.3
No payments needed for 18 months
Provides in-house financing
Offers top brands like LG and Trina
3.9
Highly rated customer service
Provides 24/7 panel monitoring
Solid A+ rating with the BBB
What Do the Solar Battery Specs Mean?
As you sift through your options for a battery storage system, you’ll learn about various specifications of each battery. Learn what they are and what they mean. Among them:
- Depth of discharge (DoD): Expressed as a percentage, this number tells you the amount of the battery’s capacity you can discharge frequently without damaging or significantly reducing its lifespan. The best solar batteries usually boast DoD percentages of 90% or higher.
- Continuous power: This number, expressed in kilowatts, tells you the amount of power the battery can generate in a standard, non-peak operating condition. Most solar batteries feature continuous power ratings of 5 kW or higher, which is sufficient for most situations.
- Round-trip storage efficiency: This number, expressed as a percentage, tells you the efficiency of the charge and discharge of the battery — how much you get out based on what you put in. The industry standard is 80%, but higher numbers indicate better performance.
- Cycle life: This tells you the number of charge and discharge cycles a battery has before it reaches the end of its life. But pay close attention because specifications vary. Some manufacturers express cycle life in full cycles, while others count partial cycles as complete. Most solar batteries come with a cycle life of 4,000 to 10,000 cycles. More is better.
- Megawatt-hour throughput: This specification tells you the total energy you can expect the battery to move through over its lifetime and is expressed in megawatt-hours (MWh). Some manufacturers specify a certain throughput that, once met, ends the warranty.
Read also: Different Solar Panel Systems
So, What’s the Ideal Solar Battery for Your Home?
The best solar battery bank differs for every homeowner because needs and expectations vary. As you shop for a solar battery backup system, prioritize your needs and shop according to those: size of your home, energy demands, budget, and expectations. Find the battery that checks the most important boxes.
Once you decide on a particular make and model, we recommend obtaining energy storage system quotes from several local providers. This will ensure you get the best price possible.
FAQs about Solar Batteries
Is There a Difference in Solar Batteries?
Not all solar batteries are created equal. You’ll see different specs from varying brands. Different types of solar batteries have particular features and specifications.
How Many Solar Batteries Are Needed to Power a House?
The number of solar batteries you need to power your house depends on multiple factors, including the size of your home, energy demand, and energy goals. For example, if you want to transition to off-grid living, you’ll likely need a few batteries to ensure you have all the power you need. Conversely, if you only want supplemental backup power for outages or long periods with no sun, one or two batteries might do the trick. But you’ll also need enough solar panels to charge the batteries.
What Is the Best Solar Battery for a Power Outage?
Most solar batteries handle lapses in power from an outage, but the best battery option for you hinges on your needs. You need to consider the size of your home, use habits and needs, and budget.
Methodology: How We Rank Solar Batteries
At Today’s Homeowner, we strive to bring you the most transparent, accurate information for your home improvement projects. We want you to have all the information you need to choose the solar battery that’s right for your home energy needs. That said, our ratings are based on publicly available information about each solar battery and online customer reviews.
A solar battery can earn a maximum of 100 points across seven categories converted to a five-star scale. We researched dozens of solar batteries to develop the following formula:
- Battery Capacity (20 points): An average household uses about 30 kWh per day, so you need a battery that can store as much energy as possible. Most solar batteries have a battery capacity of 10 kW, but the best solar batteries have 12 kW or more.
- Battery Chemistry (15 points): Not all types of solar batteries are created equal, which is why we look at the battery chemistry of each solar battery. A battery's chemistry affects its performance, and lithium-ion batteries tend to be the best in the industry. Batteries with this type rank higher in this category.
- Depth of Discharge (20 points): The depth of discharge is incredibly important to the performance of a solar battery. The depth of discharge indicates how much of the battery has been discharged compared to the total capacity of the battery. The best solar batteries have a depth of discharge of 100% and score highest in this category.
- Round Trip Efficiency (20 points): Round-trip efficiency is how much of the energy your battery receives relative to the amount of energy it can use in your home. A good round-trip efficiency is about 90%, but the best solar batteries have a round-trip efficiency of 96% or more.
- Off-grid applications (5 points): The purpose of a solar battery is to help you save money and energy by not relying on the grid. All of our top solar batteries can be off-grid, but the batteries designed for off-grid applications perform the best in this category.
- Warranty length (10 points): A good warranty can save you hundreds, if not thousands, of dollars in repair costs if your solar battery fails unexpectedly. Given that most solar batteries last between five and 15 years, the solar battery companies that offer a warranty of 10 years or longer perform the best in this category.
- End of warranty capacity (10 points): At the end of your solar battery's warranty, it should be able to hold a certain percentage of its original battery capacity. Most solar batteries have an end of warranty capacity of 60%, but the best solar batteries have 70% capacity or more capacity at the end of the warranty period.
We monitor company data on an ongoing basis to keep rankings and information up to date.
