Sheet for battery cases having gas pocket portion formed in movement direction, battery cell manufactured using the same, and method of manufacturing the battery cell

1 . A sheet for battery cases, comprising:

a first gas pocket portion a first electrode assembly receiving portion, a second gas pocket portion, and a second electrode assembly receiving portion alternately formed in a first direction, wherein the first direction is a movement direction of the sheet for battery cases, wherein the movement direction is an unwinding direction of the sheet for battery case wound in a form of a roll;

wherein a long side of the first electrode assembly receiving portion is parallel to the first direction,

wherein a short side of the first electrode assembly receiving portion is parallel to a second direction perpendicular to the first direction,

wherein the electrode assembly is a bidirectional electrode assembly having electrode leads extending outwards therefrom so as to face opposite short sides of the first electrode assembly receiving portion, and

the sheet further comprising a portion to be sealed formed along each of opposite long sides of the first electrode assembly receiving portion parallel to the first direction, and

a plurality of openings configured to allow an electrode lead of the electrode leads to be exposed therethrough, wherein a first of the plurality of openings is defined between the first gas pocket portion and the first electrode assembly receiving portion and a second of the plurality of openings is defined between the second gas pocket portion and the second electrode assembly,

wherein the sheet includes a bending line extending parallel to the first direction,

wherein the first gas pocket portion comprises a first pocket on a first side of the bending line and a second pocket on a second side of the bending line and the second gas pocket portion comprises a third pocket on the first side of the bending line and a fourth pocket on the second side of the bending line, and

wherein the electrode assembly receiving portion is disposed on the first side of the bending line.

2 . The sheet according to claim 1 ,

wherein the first receiving portion is formed on one side of the sheet for battery cases based on a first-direction central axis.

3 . The sheet according to claim 1 , wherein the first electrode assembly receiving portion comprises a first receiving sub-portion and a second receiving sub-portion, and

wherein the first receiving sub-portion and the second receiving sub-portion are formed respectively on both sides of the sheet for battery cases based on a first-direction central axis.

4 . The sheet according to claim 1 , wherein the sheet for battery cases is configured such that:

one battery case shaping line in which the first gas pocket portion and the first electrode assembly receiving portion are alternately disposed is formed in the first direction between the first electrode assembly receiving portion and the second gas pocket portion; and

two or more battery case shaping lines are formed in the second direction.

5 . A battery cell manufactured using the sheet according to claim 1 , comprising:

a first bidirectional electrode assembly having electrode leads extending outwards therefrom so as to face opposite short sides of the first electrode assembly receiving portion received in the first electrode assembly receiving portion, and

a sealed portion formed at at least a part of a periphery of the plurality of openings.

6 . A method of manufacturing the battery cell according to claim 5 , the method comprising:

(a) shaping the sheet for battery cases to form first gas pocket portion and a first electrode assembly receiving portion, the second gas pocket portion, and the second electrode assembly receiving portion therein;

(b) forming a first of the plurality of openings between the first gas pocket portion and the first electrode assembly receiving portion and a second of the plurality of openings between the second gas pocket portion and the second electrode assembly receiving portion;

(c) receiving the electrode assembly in the first electrode assembly receiving portion; and

(d) sealing the portion to be sealed of the sheet for battery cases, wherein

the first gas pocket portion, the first electrode assembly receiving portion the second gas pocket portion, and the second electrode assembly receiving portion are alternately formed in the first direction parallel to the movement direction of the sheet for battery cases.

7 . The method according to claim 6 , wherein an electrode lead of the electrode assembly is exposed through the at least one of plurality of openings.

8 . The method according to claim 6 , further comprising forming sealed portions at opposite sides of the electrode lead exposed through the at least one of the plurality of openings and removing the first gas pocket portion after the sealing step.

9 . The sheet according to claim 1 , wherein the first electrode assembly receiving portion comprises a first pocket on the first side of the bending line and a second pocket on the second side of the bending line.

10 . The sheet according to claim 1 , further comprising:

a third gas pocket portion, and a fourth gas pocket portion formed along a second direction perpendicular to the first direction subsequent to the first gas pocket portion and the second gas pocket portion, respectively, and

a third electrode assembly receiving portion, and a fourth electrode assembly receiving portion formed along the second direction subsequent to the first electrode assembly receiving portion and the second electrode assembly receiving portion, respectively.