PURPOSE: To remove plate adherence, which is a trouble in the process, without causing the generation of bad influence to performance of a battery, by using dilute sulfuric acid dissolved with sodium salt of a condensation product of β-naphthalene sulfonic acid formalin as forming liquid.

CONSTITUTION: In the so-called block forming in which several sheets of unformed positive and negative plates are alternately arranged to perform forming, dilute sulfuric acid of 1.060 specific gravity dissolved with 1% sodium salt of a condensation product of β-naphthalene sulfonic acid formalin is used to form an unformed plate for a lead storage battery. Then in this case, a counted result of adhering frequency of the plate has been shown in a table with a result from the vonvertional method. Further from a measured result of potential change of the negative plate and quantity change of residual lead sulfate at the time of forming, the smaller is a reduction speed of lead sulfate, that is, the lower is forming efficiency, a rise-up of potental seems the slower and adherence of the plate seems to be generated the more easily.