Enclosed storage battery and its manufacturing method

A manufacturing method of an enclosed storage battery comprising the steps of:

• (a) placing a plate group in a jar having an opening,
• (b) injecting electrolyte into said jar,
• (c) connecting a pole to said plate group, said pole having a leading end, wherein a recess is located on said leading end of said pole,
• (d) placing a terminal and a lid having a bushing electrically conducting with said terminal so as to cover said opening, said bushing having a portion defining a penetration hole with an inner wall,
• (e) inserting said pole from inside of said jar into said penetration hole of said bushing, said inner wall encompassing the conductive pole, positioning the leading end of the pole at a position below the upper periphery of the portion of said bushing defining the penetration hole, and
• (f) integrating said pole and said bushing by the steps of
• first (1) melting part of said pole, and joining said pole and said bushing by a second fused matter formed by melting a part of said pole, the second fused matter positioned between said hole and the inner wall, and
• then (2) melting an annular bump located on the upper periphery of said penetration hole of said bushing, and joining said pole and said bushing by a first fused matter formed by melting of said annular bump, said first fused matter formed at the leading end of the pole.