POSITIVE ELECTRODE PLATE FOR LEAD STORAGE BATTERY, AND METHOD FOR MANUFACTURING THE SAME

PROBLEM TO BE SOLVED: To provide a long-life lead storage battery by avoiding the production of 5 mass% or more of tetrabasic lead sulfate in a paste-kneading step and after maturation and drying steps, producing tetrabasic lead sulfate stable in quantity and crystallite size in a chemically unprocessed positive electrode active material layer.SOLUTION: A positive electrode plate for a lead storage battery is manufactured in such a way that a paste-like positive electrode active material to be retained is filled in a current collector and then, maturated and dried, in which a water content in the positive electrode active material is made 8 mass% or more at the start of maturation, and the water content in the positive electrode active material is kept at 7 mass% or more for 12 hours or longer from the start of maturation. In this way, a positive electrode plate for a lead storage battery, including 10 mass% or more of tetrabasic lead sulfate after drying, and having a tetrabasic lead sulfate crystallite size of 140 nm or more, can be obtained.SELECTED DRAWING: None 【課題】ペースト練り行程では５質量％以上の四塩基性硫酸鉛を生成することなく、熟成・乾燥後における未化成状態の正極活物質層中に、安定した量及び結晶子径をもつ四塩基性硫酸鉛を生成させることによって、長寿命な鉛蓄電池を提供すること。【解決手段】維持するペースト状正極活物質を集電体に充填した後、熟成及び乾燥させて鉛蓄電池用正極板を作製するにあたり、熟成開始時の前記正極活物質中の水分含有量を８質量％以上とし、かつ、熟成開始から１２時間以上、前記正極活物質中の水分含有量を７質量％以上に維持することにより、乾燥後に四塩基性硫酸鉛を１０質量％以上含み、その四塩基性硫酸鉛の結晶子径が１４０ｎｍ以上である鉛蓄電池用正極板を得る。【選択図】なし