If you’ve been looking into having a solar power system, chances are good that you you’ve also thought of a battery, or at least came across an ad or two for energy storage. The combination of solar and battery together allows you to maximize the use of solar you generate even when the sun isn’t shining above. The story gets even more compelling when you look at the financial benefits of having a solid solar battery backup.

There are four main types of batteries for storing solar energy: lead-acid, lithium-ion, flow batteries, and nickel-cadmium. Lead-acid batteries are affordable but require frequent maintenance, lithium-ion batteries are efficient and maintenance-free, flow batteries offer scalability but are complex and costly, and nickel-cadmium batteries are durable but contain toxic materials. Among these, lithium solar batteries are transforming energy storage by providing an efficient and reliable solution that supports the growing use of solar power and promotes a sustainable future.

What Are Lithium Solar Batteries?

Lithium solar batteries, often referred to as the “new kid on the block” compared to lead-acid batteries, are rechargeable batteries designed to store energy from solar panels. They are known for their high energy density and low cost per cycle. While “lithium battery” is a broad term, the most common chemistry for renewable energy is Lithium Iron Phosphate (LiFePO4), valued for its safety, thermal stability, high current ratings, long cycle life, and durability.

The Advantages of Lithium Solar Batteries for Energy Storage

Lithium solar batteries offer several key advantages for energy storage:

1. Long Lifespan: Lithium batteries can last beyond 5,000 charge cycles, providing over 10 years of use, significantly outlasting lead-acid batteries, which typically endure fewer than 1,000 cycles.
2. Handling Inconsistent Charging: These batteries can easily manage the fluctuating energy input and output that is common in solar systems, ensuring reliable performance regardless of weather conditions or varying energy demands.
3. Full Capacity Utilization: Unlike lead-acid batteries, which lose voltage as they discharge, lithium batteries maintain consistent voltage, allowing you to fully utilize their capacity even at low charge levels.
4. Low Maintenance: Once installed, lithium batteries require minimal upkeep compared to lead-acid batteries, which need regular maintenance, such as water level checks and charge equalization.
5. Lightweight and Compact: Lithium batteries are lighter and more compact than other battery types, making them easier to install and ideal for situations where space and weight are critical factors.

How much do lithium-ion solar batteries cost?

Lithium solar batteries typically cost between Ksh.70,000 and Ksh.600,000. The batteries don’t come cheap, with installations ranging from Ksh.10,000 for a simple single-battery solution, to well over Ksh.50,000 for whole-home backup. This is significantly higher than that of installing lead-acid batteries.

Despite the price difference, people still tend to choose lithium-ion batteries over lead-acid because of increased performance and fewer maintenance concerns. The total cost of a solar battery installation depends on the battery brand you choose, the features it has, how many batteries you need, and labor costs.  

Applications of Lithium Solar Batteries

Lithium solar batteries are versatile and can be used in a variety of applications, including:

• Residential Solar Systems: Homeowners can store excess solar energy generated during the day for use at night or during power outages, ensuring a consistent energy supply and reducing reliance on the grid.
• Commercial and Industrial Use: Businesses can benefit from energy independence, reduced electricity bills, and uninterrupted power supply, even during peak demand periods.
• Off-Grid Solutions: For remote locations without access to the electrical grid, lithium solar batteries provide a reliable and sustainable power source, enabling energy independence.
• Emergency Backup Power: In regions prone to natural disasters or power outages, lithium solar batteries offer a dependable backup power solution, ensuring critical systems remain operational.

Are lithium-ion batteries the best solution?

In short, lithium-ion batteries are the best choice for most residential and commercial solar systems due to their long lifespan, compact size, and ability to handle inconsistent charging and discharging, offering the best return on investment.

However, lead-acid batteries may be preferable in certain situations, such as backup power, systems used infrequently, or off-grid setups, where the lower cost outweighs the need for a longer lifespan. Overall, lithium-ion batteries stand out as the top option in the solar market.