Lead acid batteries are composed of electrolyte with lead, oxide and sulfuric acid solution, cathode and lead sulfate anode.
Lead acid battery electron reaction,
Positive pole: PbSO4 + 2H2O? 2e ? === PbO2 + 4H+ + SO42?
Negative pole: PbSO4 + 2e ?=== Pb + SO42?
?? Anode: Pb + SO42?? 2e ? === PbSO4
?? Cathode: PbO2 + 4H+ + SO42? + 2e ?=== PbSO4 + 2H2O
Types of lead acid battery,
a. common lead acid battery; its plate is composed of lead, oxide and sulfuric acid solution electrolyte. Its advantage is constant voltage, cost effective; disadvantage is low energy density, short cycle life and frequent maintenance.
b. Dry charged lead acid battery, its advantage is anode plate with electricity storage capability, which can store electricity within two years in condition of complete dry status. It should be added electrolyte and wait 20-30 minutes before use.
c. Maintenance-free lead acid battery, since its self structure advantage, the consumption of electrolyte is very low, doesn’t need to add distilled water in cycle life basically. Besides it has characteristic like anti-vibrate, anti-high temperature, small size, low self-discharge etc. Cycle life is two time of common one. There are two types of maintenance-free battery in the market, one is add electrolyte at the first time of purchase, another is added electrolyte and sealed before left factory.
Lead acid battery voltage includes 2.4/4/6/8/12/24V series, capacity from 200Mah to 3000Ah, VRLA battery is that rechargeable battery that on basis of AGM technology and calcium grid plate, excellent large current discharge characteristic and super long cycle life, no necessary to add water when use.