Best solar batteries for your home in 2025

None of the best batteries on our list are NMC. While NMC batteries are more power-dense than LFP and LTO batteries (they take up less space per kWh of capacity), they're a little less stable.They don't last as long and are slightly more susceptible to thermal runaway, which can cause overheating, fire, or an explosion.

Most of today's best batteries are LFP. These batteries are very safe, last a long time, and are relatively affordable.

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

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

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

1. From your solar panels (DC) to your home (AC)

2. From your home (AC) to your battery (DC)

3. From your battery (DC) back to your home (AC)

Power is lost during each inversion, 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.

With a DC-coupled system, electricity is stored directly in your battery before going to your home. 

With this setup, power is only inverted once: from your battery (DC) to your home (AC).

DC-coupled systems use the same inverter (a hybrid inverter) for the solar panels and battery, so they're much more efficient. However, they don't make sense if you're adding a battery to an existing solar panel system. They're best for new solar-plus-battery systems.

Roundtrip efficiency 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.

A battery's capacity (or size) is the amount of electricity it can store and supply to your home. More specifically, usable capacity tells you 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.

While power is expressed in kilowatts (kW), battery size is expressed in kilowatt-hours (kWh), or power multiplied by time. Thus, battery size tells you how long your battery can power parts of your home. Just remember that the more power you use, the faster you'll run out of stored electricity. Here’s an example: 

A typical compact fluorescent lightbulb uses about 12 Watts (or 0.012 kW) of power, while a 3-ton AC unit draws 20 Amps, or about 4.8 kW. If you have a 5 kW, 10 kWh battery, you can only run your AC unit for two hours (4.8 kW x 2 hours = 9.6 kWh). However, that same battery would keep 20 lightbulbs on for two full days (0.012 kW x 20 lightbulbs x 42 hours = 10 kWh).

A battery's power rating is usually measured in kW and divided into two categories: continuous and peak power. Continuous power refers to how much electricity a battery can consistently output, which is important if you want to run multiple devices simultaneously. 

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.

Warranties cover a battery’s integrity and output for a specific duration, usually around 10 years. As with any warranty, read these documents closely: There are often clauses that can void your warranty if you don't follow them.

Each time you drain and charge your battery, it slightly reduces its ability to hold a full charge. Many brands promise that your battery maintains 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.

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 your battery can move through during its lifetime, while cycles measure how many times you can charge and drain it. 

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 cycle's 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.

Batteries with high usable capacities last a long time (if you don't use too much power at once). 

The average home needs a battery system that's at least 30 kWh to run for a full day without recharging. But most people just choose a few critical loads to power with their battery during outages, in which case you can get away with a smaller battery (about 10 kWh).

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

If you want to power most of your appliances simultaneously, look for a battery with a high continuous power rating.

Choose a battery with a high peak power rating to power appliances that require high start-up power (such as a sump pump). 

As a reminder, using more power will drain your battery faster. If you need a lot of power, make sure your battery’s usable capacity can support these power outputs over time.

AC-coupled batteries are usually the way to go if you already have solar and want to add storage. While 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. 

If your roof is shady, you should also consider an AC-coupled battery. Microinverters maximize solar production by converting electricity at the panel level, but they aren’t compatible with DC-coupled batteries. Instead, DC-coupled batteries require a hybrid inverter that works for both solar and storage.

If you plan to install your battery outside, ensure its enclosure is outdoor-rated. Your installer can help you determine which batteries are suitable for outdoor use and which are better suited for indoor use. 

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