Pouch-shaped battery cell having venting portion attached thereto and method of manufacturing the same

1 . A pouch-shaped battery cell comprising:

a pouch-shaped battery case made of a laminate sheet having an opening therein, the pouch-shaped battery case comprising an outer resin layer, a metal layer, and an inner resin layer;

an electrode assembly received in the pouch-shaped battery case; and

a venting portion attached to an inside of the opening and configured to discharge gas to an outside of the pouch-shaped battery case when a pressure inside of the pouch-shaped battery case becomes greater than an atmospheric pressure outside of the pouch-shaped battery case,

wherein the venting portion has a first layer having pores formed therein and a second layer having no pores formed therein, the first layer being stacked with the second layer,

wherein a portion of the first layer of the venting portion and the inner resin layer of the pouch-shaped battery case directly contact each other,

wherein a portion of the inner resin layer extends into the pores of the first layer, thereby coupling the inner resin layer and the first layer to each other, such that no pores remain in the portion of the first layer that directly contacts the inner resin layer,

wherein the first layer and the second layer are each consisting of polytetrafluoroethylene (PTFE), and

wherein the pouch-type battery case has a first thickness where the venting portion is attached and a second thickness where the venting portion is not attached, and the first thickness is thinner than the second thickness.

2 . The pouch-shaped battery cell according to claim 1 , wherein the venting portion is attached to a portion of the pouch-shaped battery case adjacent to a sealed portion of the pouch-shaped battery case.

3 . The pouch-shaped battery cell according to claim 1 , wherein the pouch-shaped battery case comprises a first case portion having an electrode assembly receiving portion formed therein and a second case portion coupled to the first case portion, the second case portion being configured to hermetically seal the pouch-shaped battery case together with the first case portion, and

the venting portion is attached to at least one of a central portion of the first case portion and a central portion of the second case portion.

4 . A method of manufacturing a pouch-shaped battery cell, the method comprising:

(a) preparing a laminate sheet having an opening formed therein;

(b) attaching a venting portion to the opening, the venting portion having a first layer having pores formed therein and a second layer having no pores formed therein, the first layer being stacked with the second layer;

(c) shaping the laminate sheet to manufacture a pouch-shaped battery case; and

(d) placing an electrode assembly in the pouch-shaped battery case and hermetically sealing the pouch-shaped battery case,

wherein a portion of the first layer of the venting portion and an inner resin layer of the pouch-shaped battery case directly contact each other,

wherein a portion of the inner resin layer extends into the pores of the first layer, thereby coupling the inner resin layer and the first layer to each other, such that no pores remain in the portion of the first layer that directly contacts the inner resin layer,

wherein the first layer and the second layer are each consisting of polytetrafluoroethylene (PTFE), and

wherein the pouch-type battery case has a first thickness where the venting portion is attached and a second thickness where the venting portion is not attached, and the first thickness is thinner than the second thickness.

5 . A battery pack comprising the pouch-shaped battery cell according to claim 1 .