Electric energy storage device having improved terminal structure

An electric energy storage device having an inner terminal disposed in a cylindrical metal case and connected to an electrode of a bare cell,

• wherein the inner terminal includes a plate-shaped terminal body having a circular outer circumference and a flange located at the outer circumference of the terminal body and extending perpendicular to a plane of the terminal body,
• wherein the terminal body is provided to face the bare cell and coupled thereto to make surface contact,
• wherein a portion of a side of the metal case corresponding to the inner terminal is formed to have a greater thickness than the other portion of the side,
• wherein the flange is formed to have a lower height in comparison to the height of the thick side of the metal case, and
• wherein a beading portion is formed at the metal case by beading a part of a side of the inner terminal at a portion corresponding to the flange so that the beading portion is closely adhered to the flange when the flange is deformed, and the inner terminal is secured and fixed by means of the beading portion.

An electric energy storage device having an inner terminal disposed in a cylindrical metal case and connected to an electrode of a bare cell,

• wherein the inner terminal includes a plate-shaped terminal body having a circular outer circumference and a flange located at the outer circumference of the terminal body and extending perpendicular to a plane of the terminal body,
• wherein the electric energy storage device comprises a top plate member fitted in a top portion of the metal case to seal an opening of the metal case, the top plate member having a circular outer circumference,
• wherein the top plate member includes a coupling protrusion formed at a lower side thereof concentrically with the circular outer circumference and protruding to open the inside thereof, and the top plate member is inserted into the flange of the inner terminal to give an inner space between the top plate member and the inner terminal,
• wherein a hollow is formed at a center of the top plate member to inject an electrolyte, and
• wherein an electrolyte leakage prevention unit having a gradient to protrude downwards is formed around the hollow at the lower surface of the top plate member.