Lead–calcium alloys with tin and aluminum as additional alloying elements are the major battery grid materials for maintenance-free automobile, standby power, submarine, and valve-regulated lead–acid (VRLA) batteries. The alloys vary considerably depending on the battery type and grid production process. Lead–calcium alloys utilize only a small amount of calcium to provide the required mechanical properties for modern battery grids. The calcium content varies between 0.03% and 0.15.
* Lead–calcium alloys containing 0.02–0.04% calcium have been used extensively in standby power and submarine batteries for over 60 years. These batteries operate in float service and are discharged infrequently.
* Lead–calcium alloys containing 0.06–0.10% calcium are used as the negative grid material for permanent book mold cast stationary, submarine, VRLA, and other large batteries. The alloy is also used for continuously cast negative grids via the concast process, continuously cast strip for expansion, and rolled strip for expansion into grids for automobile and VRLA batteries.
* Lead–calcium alloys containing 0.10–0.18% calcium alloys are used as negative grid alloys for thin permanent mold cast automobile grids.