PURPOSE: To inhibit formation of a passive state layer of sulfate on the surface of lead particles, to provide a lead-acid battery of excellent cycle life by containing lead power, in which the carbon fiber is protruded or is penetrated in an integrated mode, as a negative electrode active material, to improve the utilization factor of the negative electrode active material.

CONSTITUTION: Lead is electroplated on a carbon fiber, and lead is precipitated on the carbon fiber dispersedly like a rosary, which is cleaned thoroughly in a water washing bath, and then, the carbon fiber part is cut by a grinder. A carbon fiber 1 is formed in such a way that lead particles 2 are penetrated thereby. A small amount of lignin and barium sulfate are added to the lead powder, which is kneaded with water and dilute sulfuric acid being dropped therein, following the normal way. After this is filled in a lattice made of Pb-Ca alloy, a negative non-formed plate is provided through aging and drying.