What is the difference between maintenance-free batteries and traditional batteries?

Which is better, maintenance-free batteries or traditional batteries? From a usage perspective, there is no qualitative difference between the two batteries. Maintenance-free batteries have already been filled with electrolyte when they leave the factory. Traditional water-filled batteries need to be filled after they are purchased and used for a long time. Maintenance-free batteries do not require replenishing of purified water throughout their life cycle. Traditional water-added batteries need to add pure water when the electrolytic fluid level is lower than the minimum level. The self-discharge of lead-calcium flakes of maintenance-free batteries is small, while the self-discharge of low-antimony flakes of water-added batteries is relatively high. The charging requirements for maintenance-free batteries are relatively high, while the charging requirements for traditional water-added batteries are relatively rough. Ordinary batteries; the plates of ordinary batteries are composed of lead and lead oxide, and the electrolyte is an aqueous solution of sulfuric acid. Its main advantages are stable voltage and low price; its disadvantages are low specific energy (that is, the amount of electrical energy stored per kilogram of battery), short service life, and frequent daily maintenance. Due to its structural advantages, maintenance-free batteries consume very little electrolyte and basically do not need to replenish distilled water during their service life. It also has the characteristics of impact resistance, high temperature resistance, small size and low self-discharge. The service life is generally twice that of ordinary batteries. Maintenance-free battery recommendations for traditional batteries: maintenance-free batteries for passenger cars (cars), traditional water-filled batteries for commercial vehicles (transportation vehicles). Because the maintenance-free battery uses a lead-calcium alloy grid frame, water decomposition and water evaporation are low during charging, and the sealed structure of the casing also reduces the release of sulfuric acid gas. Therefore, compared with traditional batteries, it has the advantages of not needing to add any liquid, less corrosion to terminals, wires and body, strong resistance to overcharge, large starting current, and long storage time, and is welcomed by car users. Overview of the advantages of maintenance-free batteries: - No need to add distilled water during use. - Less self-discharge and long service life. -The terminals have little corrosion. -Good overcharge resistance. -Good startup performance.