Pouch exterior material for secondary battery, pouch type secondary battery using the same, and method of manufacturing the same

A pouch type secondary battery comprising:

• an electrode assembly;
• and
• a sheet type pouch exterior material packing the electrode assembly,
• wherein the pouch exterior material comprises:
• a sheet having an upper surface and a lower surface;
• an inserting portion provided at a center of the sheet and having a width equal to a thickness of the electrode assembly, the inserting portion having two sides and two ends, a first sidewall and a second sidewall extending downwardly from the upper surface of the sheet and a bottom wall extending between the first sidewall and a second sidewall;
• and
• accommodating portions provided symmetrically at two sides of the inserting portion and gradually deepening from a portion corresponding to a width center of the electrode assembly towards a portion corresponding to an edge of the electrode assembly,
• wherein the inserting portion further comprises a triangular stepped portion provided at the two ends of the inserting portion, each triangular stepped portion having a depth gradually decreasing towards an end.

A method of manufacturing a pouch type secondary battery, the method comprising:

• preparing a sheet type pouch exterior material for packing an electrode assembly, the pouch exterior material comprising:
• a sheet having an upper surface and a lower surface;
• an inserting portion provided at a center of the sheet and having a width equal to a thickness of the electrode assembly, the inserting portion having two sides and two ends, a first sidewall and a second sidewall extending downwardly from the upper surface of the sheet and a bottom wall extending between the first sidewall and a second sidewall;
• and
• accommodating portions provided symmetrically at two sides of the inserting portion and gradually deepening from a portion corresponding to a width center of the electrode assembly towards a portion corresponding to an edge of the electrode assembly,
• wherein the inserting portion further comprises a triangular stepped portion provided at the two ends of the inserting portion, each triangular stepped portion and having a depth gradually decreasing towards an end;
• mounting a side surface of the electrode assembly upright on the inserting portion and stacking the accommodating portions by folding up the pouch exterior material from both sides;
• and
• thermally fusing a surrounding region of the stacked accommodating portions.