An object of the present invention is to take fundamental measures against the phenomenon that the positive current collector of a lead-acid battery elongates due to corrosion, in consideration of a mechanism, and to inhibit corrosion elongation. A current collector is prepared by the steps of: mixing a lead oxide of pinning compounds for inhibiting recrystallization with the atomized powder of lead or a lead alloy; and then powder-rolling the mixture. A lead-acid battery is composed with the use of the current collector.