Sealed batteries

Abstract

A sealed battery of the invention includes a bottomed cylindrical housing accommodating an electrode assembly and an electrolytic solution, and a sealing unit fixed by crimping of an open end of the housing, the sealing unit including at least a valve body, a terminal plate welded to a central portion of the valve body so as to be farther inside the battery than the valve body, and an annular insulating member disposed between outer peripheral portions of the valve body and of the terminal plate, the terminal plate having a welded portion formed as a fusion mark during welding with the valve body, the terminal plate having a thin portion disposed around the welded portion, the distance from the outermost edge of the welded portion to the thinnest part of the thin portion being not more than 1 mm.

Dependencies are inferred from the claim text.