Grid alloys for maintenance-free deep-cycling batteries

Abstract

The basic principles of alloying are outlined and applied to lead alloys for use as grids in cells for maintenance-free deep-cycling applications. Conventional leadantimony alloys are unsatisfactory from the maintenance-free point of view. Dilute leadantimony alloys have suitable metallurgical properties but passivation of the grids causes premature failure during cycling. Alloys in which the antimony is tied up as a compound (e.g., SbCd) have good properties and cells containing such alloys can have a satisfactory cycle-life. Experience will show whether antimony poisoning will eventually affect their maintenance-free characteristics. Cells containing antimony-free alloys (e.g., leadcalcium and leadcalciumtin) have been used successfully in maintenance-free standby cells, but are known to have poor cycling properties. Alternative antimony-free alloys, such as those based on the leadstrontium system have good properties and should be investigated as possible grid alloys for deep-cycling cells.