PURPOSE: To present an electrode plate group for eliminating unwelding of a part of a lug an electrode plate even if width of a connecting shelf is formed into a dimension as same as width of a lug of an electrode plate.

CONSTITUTION: Electrode plates respectively having a notch part B, for example, a notch formed into a shape such as C, inverted C, J, inverted J, L and inverted L in a part of the tip of a lug part to be welded are used to form a group. With this notch B, the tip of a lug of an electrode plate to be welded is melted sufficiently with the flame of a welding burner B to be fused with a lead 3 at the time of forming a connecting shelf. Width of a connecting shelf of an electrode plate group can be thereby made as same as width of a lug of the electrode plate or a little wider than that, and a light lead accumulator having excellent volume efficiency can be realized.