The best solar battery in 2024: Peak performance & price


Losing power can be scary, but it doesn't have to be. With a solar system and battery storage, your home can essentially remain powered indefinitely during extended outages.


Not everyone needs a home battery. But if you don't have access to a great net metering program, frequently experience power outages, or just want more independence from your utility company, they can be a great purchase.

There are dozens of batteries to choose from––so how do you select the best one? It generally comes down to the battery's chemistry, performance, customization, warranty, and price. From there, you need to think about why you want a battery, and what you need to power with it.

We'll walk you through our top solar battery picks: Any of them could be a great addition to your home, depending on your needs.


You've done all the hard work on your end! Now it's time to watch it pay off with a brand new solar panel system. Before installation day, your solar company will begin submitting the paperwork required for installation, interconnection to the grid, and any available incentives.

On the day of your installation, you can expect about five to 10 employees of your installation company to be onsite. The crew will include certified electricians and installers who will be up on your roof attaching the panels. Depending on the size and scope of your installation, it will likely take about one to three days to complete.

Following your installation, you'll need permission to operate (PTO) from your utility before your installer can turn on your system, which can take anywhere from a few weeks to a few months. As part of PTO, your utility company will likely send a representative to your house to examine your system and install or update your meter so they can track the solar energy you send to the grid.

Once PTO is complete, you'll receive official documentation to turn your solar panel system on for electricity generation!

Our top battery picks

What are the best solar batteries?

1. Duracell Power Center Max Hybrid


You've long been able to power your TV remote with Duracell batteries––now you can use them to power your entire home. Duracell is one of the most recognizable battery brands in the world, so it's no surprise that it offers a stellar home battery.


There are a few key reasons why we chose the Duracell Power Center Max Hybrid as the best solar battery:

All-in-all, the Duracell Power Center is a top-tier battery. The only thing we don't love is that it can't be DC-coupled, so you'll lose some power during electricity inversions. Its starting size is also pretty big at 15 kWh, so if you don't need that much capacity, it might not be the right battery for you.

  • It provides the highest continuous power, meaning you can power a lot of devices at once.

  • If you're willing to buy multiple Power Center batteries, they'll power your home for days on end.

  • It's on the more affordable end of batteries, based on quotes through the EnergySage Marketplace.

2. HomeGrid Stack'd Series


You may not recognize the name HomeGrid, but the company makes a powerful battery that's particularly good for those interested in going off-grid.

Here's why we like HomeGrid's Stack'd Series:

  • It's the most scalable battery, with the highest maximum usable capacity (systems can be up to 476 kWh!). The average person won't need a battery system this big, but it's great if you have a large home and want to go off-grid. And, the scalability ensures you only pay for what you need even if you need much less than the maximum capacity.

  • It's super efficient. As a DC-coupled battery with 98% efficiency, very little energy is lost.

  • It provides plenty of power––enough to run most household appliances at once.

Unfortunately, if you already have solar and want to add a battery, you should skip this one because it can only be DC-coupled. It also doesn't have the strongest warranty, guaranteeing only 60% of initial capacity by year 10. Other than that, HomeGrid's Stack'd Series is a solid pick.

3. Villara VillaGrid

Villara's VillaGrid battery comes with the longest warranty (20 years!) thanks to its special battery chemistry (lithium titanium-oxide or LTO), which increases its recharge capabilities. The VillaGrid also doesn't contain any carbon, which makes it extra safe. But you shouldn't be worried about the safety of any of the batteries on our list––the rest use lithium-iron phosphate (LFP) chemistry, which is also very stable.


Our favorite things about the VillaGrid:

  • It has the longest warranty, guaranteeing 70% of initial capacity at 20 years.

  • It offers the highest peak power output, making it a great choice if you have power-hungry appliances requiring a lot of start-up power.

  • It's the most efficient battery on our list at 98.5% round-trip efficiency.

The VillaGrid has a lot to offer, but it didn't come in at number one because it's the only battery out of our top five picks that can't support extended outages. Depending on what you're powering, you can drain the 11.5 kWh battery pretty quickly. Its LTO chemistry also makes it less power-dense than the average battery, so it takes up a fair amount of space.


The VillaGrid can come with some sticker shock: It's more than double the cost of some batteries on our list, but it will also last twice as long.

4. Savant Storage Power System

Savant is a luxury smart home company, offering products that make your home comfortable, convenient, and sustainable. Savant's Storage Power System integrates directly with its Power Modules (which make your electrical panel smart) and its Level 2 EV Charger for complete control over your home's energy use.


But even if you don't plan on getting Savant's full product suite, its battery can still be worth it. All around, the Storage Power System is a solid battery choice. Here's why:

  • It's very scalable, up to 180 kWh. Most people won't even need that much power.

  • It has very high peak and continuous power so you can power multiple devices at once.

  • You can directly integrate it with Savant's product suite for luxury smart home living.

Like HomeGrid, you can't add the Savant Storage Power System to an existing solar panel system because it's DC-coupled. Its smallest usable capacity is also relatively large at 18 kWh, so it may provide more backup power than some homes need. These homeowners could save money by selecting a smaller battery.

5. Tesla Powerwall 3


Tesla recently replaced its Powerwall 2 with the Powerwall 3. So far, most installers and homeowners seem to love it. The Powerwall 3 uses LFP battery chemistry (the Powerwall 2 used NMC, which is less stable) and offers much higher power output. But the biggest update to the old battery is that the Powerwall 3 comes with an integrated hybrid inverter.

Many installers carry the Powerwall 3, so if you're interested, you shouldn't have any trouble installing it.


Here's why we (and the industry as a whole) think the Tesla Powerwall 3 is a great choice:

  • It has solid peak and continuous power ratings, providing ample power for most homes.

  • It can be DC or AC-coupled––but you'll get the most out of it if you DC-couple it with a new solar panel system because it comes with a built-in hybrid inverter.

  • It's relatively affordable.

If you have a shady roof and want panel-level optimization for your solar panel system (e.g., microinverters or power optimizers), you might consider skipping the Powerwall 3. You'll get the most out of the Powerwall 3 by DC-coupling it, which means using the Tesla hybrid inverter that comes with it.

How we developed our best solar battery ranking


To determine which solar batteries are best, we evaluated dozens of battery models quoted through the EnergySage Marketplace. Here's how we compared them:

Battery chemistry

A battery's chemistry refers to the primary compound used to store electricity inside the battery. It's arguably the most important characteristic to compare because it ultimately determines a lot of the battery's characteristics.

Today, most home batteries use lithium-ion chemistry, which can be broken down into three primary categories: Lithium Nickel Manganese Cobalt Oxide (NMC), Lithium Iron Phosphate (LFP), and Lithium Titanium Oxide (LTO).

Battery chemistry

None of the best batteries on our list are NMC––while they're more power-dense than LFP and LTO batteries (so they take up less space per kWh of capacity), they're a little less stable, meaning they don't last as long and are slightly more susceptible to thermal runaway.

LFP

Most of the best batteries today are LFP: they're very safe, last a long time, and are relatively affordable.

LTO

LTO batteries are the cream of the crop (other than being the least power-dense) but have a high upfront price point.

Battery performance


You can think about a battery's performance in a few different ways: how much power it can provide at once, how much capacity it has to store power, and how efficient it is at supplying that power.

Power output

A battery's power rating is usually measured in kW and is typically split into two important categories: continuous power and peak power. Continuous power refers to how much electricity it can consistently output and is important if you want to run multiple devices at once.


For example, a typical compact fluorescent lightbulb uses about 12 Watts (or 0.012 kW) of power, while a 3-ton AC unit will draw 20 Amps, or about 4.8 kW. Not every battery on the market can power an AC unit––but all of the batteries on our list can.


Peak power expresses how much power a battery can provide in short bursts (usually 5-10 seconds)––it's important if you have an appliance like a sump pump that requires a large amount of power to turn on but then runs at lower power.

Capacity

A battery's capacity (or size) is the amount of electricity it can store and supply to your home. While power is expressed in kW, battery size is expressed in kilowatt-hours (kWh), or power multiplied by time. It tells you how long your battery can power parts of your home.


Make sure to look at the battery's usable capacity to understand how much stored electricity you can actually access. A battery with a depth of discharge (DoD) below 100% will have a usable capacity lower than its total capacity, meaning you can't access all of its capacity.


It may seem obvious, but the more power you use, the faster you'll run out of stored electricity. This makes the size of a battery slightly misleading because the length of time a battery's charge will last is directly influenced by how much power it's outputting.

Let's look at the fluorescent light bulb and AC unit again: If you have a 5 kW, 10 kWh battery, you can only run your AC unit for two hours (4.8 kW 2 hours = 9.6 kWh). However, that same battery would keep 20 lightbulbs on for two full days (0.012 kW 20 lightbulbs 42 hours = 10 kWh).

Efficiency

Roundtrip efficiency is a system-level metric that measures how well your solar power system (battery and inverter) converts and stores electricity.


There are losses associated with any electrical process, meaning you'll lose some kWh of electricity when you invert it from direct current (DC) electricity to alternating current (AC) electricity or when you put electricity into a battery and take it out again. A solar battery's roundtrip efficiency tells you how many units of electricity you'll get out of a battery for every unit of electricity you put into it.

System configuration

A battery's coupling refers to its configuration relative to your solar inverter and electrical panel. There are two ways batteries can be coupled: alternating current (AC) coupling and direct current (DC) coupling.

AC - Coupled

In an AC-coupled system, the electricity flows from your solar panels to your home before being stored in your battery.


In this setup, the power in your battery will have been inverted three times before you use it:


During each inversion, power is lost––so it's not very efficient. However, it's the easiest and cheapest setup if you're adding batteries to an existing solar panel system.

  • From your solar panels (DC) to your home (AC)

  • From your home (AC) to your battery (DC)

  • From your battery (DC) back to your home (AC)

During each inversion, power is lost––so it's not very efficient. However, it's the easiest and cheapest setup if you're adding batteries to an existing solar panel system.

Warranty

The primary metrics to look at when comparing battery warranties are the length and the end of warranty capacity. It's also worth checking if the warranty includes a throughput or cycles clause.

Length

Your battery's integrity and output is covered during the duration of the warranty length. But make sure to read the warranty documents closely: There are often clauses that can void your warranty if you don't follow them.


Most popular batteries come with a 10-year warranty. Some of the best warranties are 15 or even 20 years long.

End of Warranty Capacity

Each time you drain and charge your battery, it slightly reduces its ability to hold a full charge. Many brands promise that your battery maintain a certain percentage of initial capacity by the time your warranty term is up. To calculate the warrantied capacity at the end of the warranty term, multiply the end of warranty capacity percentage by the battery's initial usable capacity.

Throughput or cycles clause

Some battery companies include a throughput or cycles clause so you don't overuse your battery during the warranty period.

These clauses are similar to a car's mileage warranty. Throughput tells you how much electricity you can move through your battery during its lifetime. Cycles measure how many times you can charge and drain your battery.

To convert a battery's expected or warranted throughput into full cycles, divide its throughput (expressed in kWh) by its usable capacity. Then, you can estimate its expected lifespan by dividing that cycles number by the number of days in the year.
A 20,000 kWh throughput warranty on a 10 kWh battery means 2,000 expected cycles, or a cycle per day for 5.5 years.

Price

Batteries vary a lot in price. But generally it costs about $9,000 after the federal tax credit to install a 10 kWh battery that will back up your essential devices. Choosing a more expensive battery can be worth it: Villara's VillaGrid lasts twice as long as the average battery! Just make sure you understand why the battery is more expensive than average to ensure that it's worth it.

How to choose the best solar battery

While we think the Duracell Power Center is the best battery overall, that doesn't mean it's right for you. Some batteries are ideal for certain setups, but won't work in others. It's important to choose the battery that's best for your home, considering your solar setup and why you want a battery.

How long do you need backup power?

Batteries with high usable capacities will last a long time (if you don't use too much power at once). The average home needs a battery that's at least 30 kWh to run for a full day without being recharged. But most people just choose a few critical loads to power with their battery during outages, in which case you can generally get away with a smaller battery––about 10 kWh.

If you want to go off-grid or power your full home for days on end, you'll likely need 60 kWh or more unless you don't use much electricity.

What do you want to power?

If you want to power most of your home at once, look for a battery with a high continuous power rating. If you want to power appliances requiring high start-up power (like a sump pump), choose a battery with a high peak power rating. Just remember, as we explained above, using more power will drain your battery faster. So make sure to support the high power output with a high usable capacity battery system.

Do you already have solar–and how shady is your roof?

If you already have solar and want to add a battery to your system, go with an AC-coupled battery. While they're less efficient than DC-coupled batteries, they're much easier to retrofit to an existing solar panel system and will save you a lot of money.

You might also consider an AC-coupled battery over a DC-coupled battery if you have a shady roof. Because DC batteries need to be paired with a hybrid inverter that works for both solar and storage, they don't work with microinverters, like Enphase, which convert electricity at the panel level to minimize shading impacts.

Some DC battery setups can be paired with power optimizers, which mitigate electricity losses from shading by conditioning the electricity at each panel. This can be a great workaround to get a DC-coupled battery even if you have a shady roof.

Where will you put your battery?

If you want to put your battery outside, make sure its enclosure is outdoor-rated. Your installer will be able to help you figure out which batteries can go outside, and which are better suited for indoors.

Some batteries can also be mounted to walls, while others have to stay on the ground––this can take up a fair amount of space. Like we explained above, when it comes to lithium-ion batteries, LTO batteries take up the most space per kWh capacity, and NMC batteries take up the least space. LFP batteries are somewhere in the middle.