A secondary battery that includes an electrode assembly and an exterior body housing the electrode assembly. The exterior body includes a cup-shaped exterior member and a lid-shaped exterior member connected to each other by a welded part. An end part of at least one of the cup-shaped exterior member and the lid-shaped exterior member includes a stepped part on an inner surface thereof. The stepped part includes a first extending surface and a second extending surface extending in substantially a same direction and having different heights from each other, and a stepped surface connecting the two extending surfaces. The welded part is in a part of the stepped part, and the stepped surface of the stepped part is separated from an opposed part of the exterior body.

A secondary battery that includes an electrode assembly and an exterior body housing the electrode assembly. The exterior body includes a cup-shaped exterior member and a lid-shaped exterior member connected to each other by a welded part. An end part of at least one of the cup-shaped exterior member and the lid-shaped exterior member includes a stepped part on an inner surface thereof. The stepped part includes a first extending surface and a second extending surface extending in substantially a same direction and having different heights from each other, and a stepped surface connecting the two extending surfaces. The welded part is in a part of the stepped part, and the stepped surface of the stepped part is separated from an opposed part of the exterior body.

An electric tool includes a body portion, a grip portion including a gripping part designed to be held by a user with his or her hand, and a battery pack. The body portion is connected to a first end portion of the grip portion. The battery pack is attached to a second end portion thereof. The electric tool in its entirety, including the body portion, the grip portion, and the battery pack, may stand by itself with a bottom surface, opposite from the grip portion, of the battery pack put on a mounting surface. The battery pack includes a plurality of all-solid-state batteries, each of which is formed in a sheet shape. The plurality of all-solid-state batteries are stacked one on top of another.

An electric tool includes a body portion, a grip portion including a gripping part designed to be held by a user with his or her hand, and a battery pack. The body portion is connected to a first end portion of the grip portion. The battery pack is attached to a second end portion thereof. The electric tool in its entirety, including the body portion, the grip portion, and the battery pack, may stand by itself with a bottom surface, opposite from the grip portion, of the battery pack put on a mounting surface. The battery pack includes a plurality of all-solid-state batteries, each of which is formed in a sheet shape. The plurality of all-solid-state batteries are stacked one on top of another.

Various embodiments may relate to an electrode. The electrode may include an electrode core including an electrode active material. The electrode may also include one or more monolayer amorphous films. Each of the one or more monolayer amorphous films may be a continuous layer surrounding the electrode core.

Various embodiments may relate to an electrode. The electrode may include an electrode core including an electrode active material. The electrode may also include one or more monolayer amorphous films. Each of the one or more monolayer amorphous films may be a continuous layer surrounding the electrode core.

A current collector is disclosed and comprises a conductive material and an elemental metal of a group 6 metal contacting the conductive material. Also disclosed are an electrochemical cell comprising a current collector, a cathode adjacent to the current collector, and an alkali metal-based electrolyte between the current collector and the cathode, with the cathode separated from the group 6 metal by the alkali metal-based electrolyte. A method of operating the electrochemical cell is also disclosed.

A current collector is disclosed and comprises a conductive material and an elemental metal of a group 6 metal contacting the conductive material. Also disclosed are an electrochemical cell comprising a current collector, a cathode adjacent to the current collector, and an alkali metal-based electrolyte between the current collector and the cathode, with the cathode separated from the group 6 metal by the alkali metal-based electrolyte. A method of operating the electrochemical cell is also disclosed.

The disclosure provides a battery, a battery apparatus and a battery manufacturing method. The battery manufacturing method includes: providing a first housing including an intermediate part and a first flange, and the intermediate part being a flat plate; or the intermediate part including a top wall and a first side wall enclosing a first accommodating cavity having an opening; providing a second housing including a bottom wall and a second side wall enclosing a second accommodating cavity having an opening, the second side wall extending outward from the opening of the second accommodating cavity to form a second flange, the depth of the first accommodating cavity being smaller than the depth of the second accommodating cavity; disposing a welding head at a side of the first housing away from the second housing, and welding the first flange and the second flange.

The disclosure provides a battery, a battery module, a battery pack, and a battery manufacturing method. The battery includes a housing, a cell, a pole assembly and a connecting piece. The housing includes two first surfaces opposite to each other in a first direction. The cell is arranged in the housing and includes a cell body and a tab portion. The tab portion includes two or more single-piece tabs extending from the lateral side of the cell body. The pole assembly is arranged on the first surface, and the tab portion and the pole assembly are connected through the connecting piece. The vertical distance between an end of the tab portion away from the lateral side of the cell body and the lateral side of the cell body is smaller than the vertical distance between the pole assembly and lateral side of the cell body.