1998 Kawasaki 750SXi Pro Service Manual Supplement, Page 15Get this manual
GENERAL INFORMATION 1-9
Pb Negative active material (charged state) (PbO)
(PbO) 1202 Oxygen generated Negative active from positive plate material
H2SO4 Electrolyte
PbS04 Negative active material (charged state)
H2O Water
Thus, the negative plate is made as not to get fully chargedEven if the overcharge continues, the oxygen gas generated inside the battery is absorbed by the negative plate, process called oxygen cycle, which keeps water loss theoretically at nil, and allows the battery to be sealed