The terminal component disclosed herein is a terminal component for use in a terminal for secondary batteries. The terminal component includes a first metal and a second metal having a recess. The first metal includes a shall having a pair of flat surfaces and a fitting portion formed at one end of the shaft in the major axis direction. At the boundary between the first metal and the second metal, a joining portion joined by ultrasonic, joining and a crimping portion where the fitting portion of the first metal is fitted into the recess of the second metal are formed. A gap is formed between the recess and the fitting portion in the facing direction in which the gap faces the flat surfaces in plan view.

A terminal part with enhanced joint strength of a joint portion between different metals is provided. A terminal part disclosed here includes a first metal and a second metal. A joint interface between the first metal and the second metal includes a first layer disposed at the second metal and containing a first intermetallic compound and a second layer disposed closer to the first metal than the first layer and containing a second intermetallic compound. In the second layer, the second intermetallic compound has grown in a dendritic pattern, and the first metal is present in a gap of the dendritic second intermetallic compound.

A terminal part with enhanced joint strength of a joint portion between different metals is provided. A terminal part disclosed here includes a first metal and a second metal. A joint interface between the first metal and the second metal includes a first layer disposed at the second metal and containing a first intermetallic compound and a second layer disposed closer to the first metal than the first layer and containing a second intermetallic compound. In the second layer, the second intermetallic compound has grown in a dendritic pattern, and the first metal is present in a gap of the dendritic second intermetallic compound.

An energy storage device includes: an electrode assembly; a case that accommodates the electrode assembly; and an external terminal made of metal and disposed in the case, in which the external terminal includes: a flange portion spreading along the case outside the case; and a shaft portion extending from the flange portion, penetrating the case, and electrically connected to the electrode assembly, in which the flange portion includes a plurality of metal layers layered in a penetrating direction of the shaft portion.

An energy storage device includes: an electrode assembly; a case that accommodates the electrode assembly; and an external terminal made of metal and disposed in the case, in which the external terminal includes: a flange portion spreading along the case outside the case; and a shaft portion extending from the flange portion, penetrating the case, and electrically connected to the electrode assembly, in which the flange portion includes a plurality of metal layers layered in a penetrating direction of the shaft portion.

Methods for electrically coupling electrode portions within electrochemical devices, and associated articles and systems, are generally described. In some cases, an electrically non-conductive layer is between multiple electrode portions that are to be coupled. In some cases, the method comprises penetrating the article to establish electrical coupling between the electrode portions previously separated by the electrically non-conductive layer.

Provided is a rectangular secondary battery with improved rigidity against vibrations and impacts. A rectangular secondary battery of the present invention includes: a flat-shaped electrode group; a current-collecting plate electrically connected to the electrode group; a battery case accommodating the current-collecting plate and the electrode group; a battery cover that closes an opening of the battery case; an electrode terminal penetrating through the battery cover, the electrode terminal being connected to the current-collecting plate via a connecting member; and a gasket that is inserted between the electrode terminal and the battery cover for insulating and sealing. An insulator is disposed between the current-collecting plate and the battery cover, the battery cover includes a battery cover side fixing part that fixes the insulator, and the insulator includes a current-collecting plate side fixing part that fixes the current-collecting plate.

An electricity storage device member is provided. The electricity storage device member includes a base material mainly composed of a metal and a resin layer stacked on the base material, in which the resin layer contains a crosslinked fluororesin.

A secondary battery includes an outer package member, an electrode terminal, and a battery device. The outer package member has a flat and columnar shape and includes a first bottom part and a second bottom part opposed to each other. The electrode terminal is supported by the first bottom part and is insulated from the first bottom part. The battery device is contained inside the outer package member and includes a first electrode and a second electrode. The first bottom part has a recess around the electrode terminal.

A secondary battery includes: an electrode assembly; a case made of steel, in which openings are provided at opposite sides and in which the electrode assembly is arranged; a side terminal electrically connected to an electrode tab of the electrode assembly; and a cap plate made of steel, through which the side terminal passes and which is coupled to an opening of the openings.