It is often seen in the terminals of car batteries, as it is formed when the battery is discharged (when the battery is recharged, then the lead sulfate can be transformed back to metallic lead and sulfuric acid on the negative terminal or lead dioxide and sulfuric acid on the positive terminal). Lead sulfate is poorly soluble in water.
Lead sulfate is toxic by inhalation, ingestion and skin contact. It is a cumulative poison, and repeated exposure may lead to anemia, kidney damage, eyesight damage or damage to the central nervous system (especially in children). Some lead salts may cause reproductive defects and cardiovascular disturbances. It is also corrosive - contact with the eyes can lead to severe irritation or burns. Typical threshold limit value (above which the substance is harmful) is 0.15 mg/m³.
At high concentration of sulfuric acid (>80%), hydrogen lead sulfate, Pb(HSO4)2, forms.
WIPO ASSIGNS PATENT TO AXION POWER INTERNATIONAL FOR "ENERGY STORAGE DEVICE WITH IMPROVED LEAD SULFATE SOLUBILITY" (AMERICAN INVENTORS)
Nov 11, 2010; GENEVA, Nov. 11 -- Publication No. WO/2010/129625 was published on Nov. 11. Title of the invention: "ENERGY STORAGE DEVICE WITH...