Battery and manufacturing method thereof

A battery comprising:

• a first cylindrical electrochemical cell having a first electrode facing a first direction;
• a second cylindrical electrochemical cell having a second electrode facing the first direction and being adjacent to the first cylindrical electrochemical cell in a second direction perpendicular to the first direction;
• a lead wire having a core wire covered by covering material and having one end connected to the first electrode;
• a metal plate connected to the second electrode;
• and
• an electrical element provided adjacent to the second cylindrical electrochemical cell and having an axial lead that extends on a first principal surface of the metal plate, the first direction being perpendicular to the first principal surface,
• wherein the axial lead includes:
• a main body part having a first diameter, and
• a connection part that is located from the main body part to an end part of the axial lead and that is connected to the first principal surface,
• wherein the connection part includes a first part which is located adjacent to the main body part, which includes a weld part welded to the first principal surface, and which has a first thickness less than the first diameter in the first direction perpendicular to the first principal surface,
• wherein the connection part includes a second part, which is located from the first part to the end part, which includes a non-weld part not welded to the first principal surface, and which has a second thickness equal to or less than the first thickness in the first direction, and
• wherein the lead wire extends from the one end connected to the first electrode toward the metal plate connected to the second electrode.