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?
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:
The customer can just plug them in. Suddenly you have the portability of the lithium battery and the inexpensive lead-acid batteries sitting at home.” The biggest problems when trying to link lithium and lead-acid together are their different voltages, charging profiles and charge/discharge limits.
Lead-acid batteries consist of lead dioxide (PbO2) and sponge lead (Pb) plates submerged in a sulfuric acid electrolyte. The electrochemical reactions between these materials generate electrical energy. This technology has been in use for over a century, making it one of the most established battery technologies available.
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.