PURPOSE: To produce mechanically strong, light-weight and high capacity lead storage battery plate, by thermally hardening maintenance-free lead alloy then performing work deformation and expanding.

CONSTITUTION: Maintenance-free lead alloy produced through roll casting is thermally hardened then applied with work deformation through cold rolling or under the temperature of 20∼120°C. Then this deformed body is expanded to produce a grid to be employed as a battery plate. With such method, mechanical strength is improved while extension of plate is limited resulting in lengthening of service life.