Lithium-ion solar cells are the most popular choice for home energy storage because they have a long lifespan, low maintenance, and don't take up as much space as other types of batteries. Lithium-ion solar cells typically cost between $12,000 and $20,000 to install.
When paired with solar panels, excess solar energy can be stored in batteries for later use, such as at night or during a power outage. Depending on the region, lithium-ion batteries can even help save money on your electricity bill.
Let's take a closer look at what you need to know before installing lithium-ion batteries.
How do lithium-ion batteries work as home energy storage?
Lithium batteries are a rechargeable energy storage solution that can be installed alone or paired with a solar system to store excess electricity.
Standalone lithium-ion batteries can be charged directly from the grid, providing homeowners with backup power during a power outage. They can also be used to avoid paying peak electricity bills, charging with grid power when electricity is cheap and discharging when it's expensive.
Combining batteries with solar will give you the most bang for your buck, especially if you can't use net metering. Lithium batteries can be charged using excess solar energy generated by solar panels, so you can power your home entirely with solar power, even when the sun isn't shining.
How much do lithium-ion solar cells cost?
Lithium-ion solar cells are expensive, with installation costs ranging from $10,000 for a simple single-battery solution to over $30,000 for a full home backup battery. This is much more expensive than installing lead-acid batteries, which typically cost $5,000 to $15,000.
Despite the price difference, people still tend to choose lithium-ion batteries over lead-acid batteries because they offer higher performance and fewer maintenance issues. The total cost of a solar cell installation depends on the brand of battery you choose, the features of the battery, the number of batteries you need, and labor costs.
What are the pros and cons of lithium-ion solar batteries?
Pros
High depth of discharge
Long lifespan
High energy density
High efficiency
Little maintenance
Cons
High cost
Thermal runaway
Advantages of lithium-ion solar batteries
Lithium-ion batteries are the most popular option for homeowners looking for battery storage for good reason. Here are some of the benefits of lithium-ion home batteries:
Higher depth of discharge (DoD)
The DoD of a battery is the amount of the stored energy in the battery that has been used compared to the total capacity of the battery. Most batteries come with a recommended DoD to maintain their health.
Lithium-ion solar batteries are deep cycle batteries, so they have DoDs around 95%. Compare this to lithium ion batteries, which have DoDs closer to 50%. Basically, this means you can use more of the energy that's stored in a lithium-ion battery and you don't have to charge it as often.
Long lifespan
Because lithium ion batteries have a high DoD and don't need to be charged and recharged as often, they have a long lifespan.
Most lithium-ion solar batteries have a minimum warrantied lifespan of around 10 years, or a cycle life of 10,000 cycles - whichever comes first. Lead acid batteries, on the other hand, only have warrantied lifespans of around 5 years.
Higher energy density
The energy density of a battery is how much power the battery can hold relative to the physical size of the battery.
Lithium-ion batteries can store more power without taking up as much space as lead-acid batteries, which is great for homes where space is limited.
High efficiency
Lithium-ion batteries have a higher round-trip efficiency rating than other types of solar batteries on the market.
Efficiency refers to the amount of usable energy you get out of your battery compared to how much energy it took to store it. Lithium-ion batteries have efficiencies between 90 and 95%.
Less maintenance
Not having to worry about regular maintenance is one of those advantages that you just can't put a price on. Lithium-ion batteries require little to no regular maintenance - just make sure they're clear of debris and. Some lead-acid batteries, on the other hand, require frequent off-gassing.
Disadvantages of lithium-ion solar batteries
Although lithium-ion batteries have numerous benefits, there are still some draw backs.
High cost
Lithium-ion batteries tend to be the most expensive battery storage option, especially when compared to lead-acid batteries.
The good news is that solar battery systems qualify for incentives like the federal tax credit, which helps make lithium-ion batteries more affordable.
It's also important to remember that while lead-acid batteries may be cheaper upfront - they have to be replaced more often, increasing your overall storage costs.
Thermal runaway
Lithium-ion batteries run a higher risk of thermal runaway, AKA overheating and catching on fire. While the risk is technically there, the chances of this happening with a properly installed lithium-ion battery is slim to none.
