To lengthen the life of a battery by preventing generation of barrier of a positive electrode plate of a negative electrode absorbing type lead-acid battery by making a larger quantity of fine powdered or reticulated tin dioxide than at the inside of an active material layer exist at a crack part reaching the surface part of the active material layer of the positive electrode plate and the surface of the electrode plate.

A negative electrode absorbing type lead-acid battery is manufactured by a sheet of a positive electrode plate and two sheets of a negative electrodes which are made of tin alloy grid made of 0.08% lead and 1.0% calcium, for instance, according to a conventional method. After the battery is assembled in a state that an electrode plate is unformed, stannous oxide or stannic oxide is dissolved in dilute sulfuric acid of specific gravity of 1.240 (20°C) and the liquid is injected. After the positive electrode plate after a battery jar is formed is washed in water and dried and distribution of tin in the electrode plate cross section direction is measured, a large quantity of the distribution state exists on the surface part of the active material layer of the electrode plate and a small quantity exists at the inside of the active material layer. In the unformed electrode plate, a crack reaching the surface of the electrode plate exists in the interface of the grid and the active material and the active material layer. On the surface of this crack, a large quantity of stannic oxide exists in the same way as the surface of the active material.