Though not the flashy new kid on the block, lead-acid batteries remain a workhorse in the energy storage world. They were the first rechargeable batteries ever created, and despite facing competition from newer technologies, they still power countless applications today.
How They Work: At their core, lead-acid batteries rely on a simple chemical reaction. Lead and lead dioxide plates immersed in a sulfuric acid solution generate electricity through reversible sulfation. Discharging the battery converts the plates and acid to lead sulfate while charging reverses the process, regenerating the active materials.
Strengths and Weaknesses: Their key strengths lie in their low cost, high surge current capability, and reliability. This makes them ideal for starting cars, providing backup power for UPS systems, and powering off-grid equipment. However, lead-acid batteries also have disadvantages. They are heavier and bulkier than newer technologies like lithium-ion, have lower energy density (meaning they store less energy per unit volume), and require regular maintenance (topping up water levels).