Sulphating

In storage battery cells, the formation of a hard white basic lead sulphate, Pb2 S05. Its formation is due to over-exhaustion of the cells. As long as the voltage is not allowed to fall below 1.90 volts per cell little of it forms. As it accumulates it is apt to drop off the plate and fall to the bottom, thus weakening the plate po ibly, and depriving it of active material, and clogging up the cell. If it carries a film of metallic lead with it, there is danger of short circuiting the cell. The presence of some sodium sulphate in the solution is said to tend to prevent sulphating, or to diminish it. Sulphur Dioxide. A compound gas, S O2; composed of   Sulphur, 32 Oxygen, 32 Molecular weight,   64 Specific gravity,    2.21. It is a dielectric of about the same resistance as air. Its specific inductive capacity at atmospheric pre ure is: 1.0037 (Ayrton). Synonyms--Sulphurous Acid--Sulphurous Acid Gas.