Battery storage is becoming an increasingly popular addition to solar energy systems. Two of the most common battery chemistry types are lithium-ion and lead acid. As their names imply, lithium-ion batteries are made with the metal lithium, while lead-acid batteries are made with lead. How do lithium-ion and lead acid batteries work?
Lithium-ion batteries also have a longer lifespan than lead-acid batteries. Thus, when considering all the factors, lithium-ion batteries are better than lead-acid batteries. However, lead-acid batteries still have their own advantages. They are less expensive than lithium-ion batteries and can be used for high-current applications.
Lead acid batteries comprise lead plates immersed in an electrolyte sulfuric acid solution. The battery consists of multiple cells containing positive and negative plates. Lead and lead dioxide compose these plates, reacting with the electrolyte to generate electrical energy. Advantages:
Disadvantages: Heavy and bulky: Lead acid batteries are heavy and take up significant space, which can be a limitation in specific applications. Limited energy density: They have a lower energy density than lithium-ion batteries, resulting in a lower capacity and shorter runtime.
A lead acid battery system may cost hundreds or thousands of dollars less than a similarly-sized lithium-ion setup - lithium-ion batteries currently cost anywhere from $5,000 to $15,000 including installation, and this range can go higher or lower depending on the size of system you need.
Most lithium-ion batteries are 95 percent efficient or more, meaning that 95 percent or more of the energy stored in a lithium-ion battery is actually able to be used. Conversely, lead acid batteries see efficiencies closer to 80 to 85 percent.