Electrochemical cell and exterior material provided therein
An electrochemical cell includes an electrode assembly including a plurality of electrodes; an exterior material including an accommodating part that accommodates the electrode assembly and a ealing part that seals the electrode assembly by bonding sealing surfaces along edges of the accommodating part; and an electrode lead connected to the electrode assembly and extended to be exposed to an outside, wherein the accommodating part includes a concavo-convex pattern extended in on one direction and disposed in a direction intersecting with the one direction, and at least a part of the concavo-convex pattern includes an adjacent portion that forms a boundary line in contact with the sealing part at an end portion in the one direction.
1. An electrochemical cell, comprising:
an electrode assembly including a plurality of electrodes;
an exterior material including an accommodating part that accommodates the electrode assembly and a sealing part that seals the electrode assembly by bonding sealing surfaces along edges of the accommodating part; and
an electrode lead connected to the electrode assembly and extended to be exposed to an outside, wherein
the accommodating part includes a concavo-convex pattern that is extended in a width direction of the electrochemical cell and that repeats in a longitudinal direction of the electrochemical cell, and
the sealing part includes an overlap area having an arc-shaped crease, which is formed by being protruded or recessed when the concavo-convex pattern is formed and then the bonding of the sealing surfaces.
2. The electrochemical cell of claim 1 , wherein the overlap area has a pattern having a lower height in a thickness direction than the concavo-convex pattern.
3. The electrochemical cell of claim 1 , wherein
the concavo-convex pattern includes an adjacent portion at an end of the concavo-convex pattern in the width direction of the electrochemical cell, the adjacent portion configured to be a boundary line in contact with the sealing part, and
the concavo-convex pattern further includes a round portion having a predetermined radius of curvature at each of both ends of the adjacent portion in the longitudinal direction.
4. The electrochemical cell of claim 3 , wherein a width (Wp) of the overlap area in the width direction and a radius of curvature (Rp) of the round portion satisfy Equation 1:
Rp/ 2≤ Wp≤ 2 Rp. [Equation 1]
5. The electrochemical cell of claim 1 , wherein
the concavo-convex pattern includes an adjacent portion at an end of the concavo-convex pattern in the width direction of the electrochemical cell, the adjacent portion configured to be a boundary line in contact with the sealing part, and
the concavo-convex pattern further includes a portion, in which the concavo-convex pattern tapers in the width direction, at each of both ends of the adjacent portion in the longitudinal direction.
6. The electrochemical cell of claim 5 , wherein a width (Wp) of the overlap area in the width direction and a half (Rp) of a width of the concavo-convex pattern in the longitudinal direction satisfy Equation 1:
Rp/ 2≤ Wp≤ 2 Rp. [Equation 1].
7. The electrochemical cell of claim 1 , wherein a width (Ws) of the sealing part in the width direction and a width (Wp) of the overlap area in the width direction satisfy Equations 2 and 3:
Ws−Wp≥ 1 mm [Equation 2]
Wp≥0.1 mm. [Equation 3]
8. The electrochemical cell of claim 1 , wherein the concavo-convex pattern includes:
a first pattern group having the overlap area at one or both ends of the first pattern group in the width direction, and
a second pattern group not having the overlap area.
9. The electrochemical cell of claim 1 , wherein the concavo-convex pattern includes:
a concave pattern that is formed to be protruded toward an inner space of the accommodating part; and
a convex pattern that is disposed adjacent to the concave pattern, has a different thickness from the concave pattern in the longitudinal direction, and is protruded in a direction opposite to the concave pattern.
10. A method of manufacturing an electrochemical cell including an electrode assembly sealed within an exterior material, comprising:
forming a concavo-convex pattern in the exterior material, the concavo-convex pattern extended in a width direction of the electrochemical cell and that repeats in a longitudinal direction of the electrochemical cell; and
forming a sealing part by overlapping and bonding two sealing surfaces of the exterior material, the sealing part including an overlap area with an arc-shaped crease,
wherein in the forming the sealing part, a part of the concavo-convex pattern is formed into the arc-shaped crease by the bonding of the two sealing surfaces.
11. The method of manufacturing an electrochemical cell of claim 10 , wherein
in the forming the concavo-convex pattern, a round portion having a predetermined radius of curvature (Rp) is formed at an end of the concavo-convex pattern in the width direction, and
in the forming the sealing part, at least a part of the round portion is included in the overlap area, and
a width (Wp) of the overlap area in the width direction satisfies Equation 1:
Rp/ 2≤ Wp≤ 2 Rp. [Equation 1].
12. The method of manufacturing an electrochemical cell of claim 10 , wherein
in the forming the concavo-convex pattern, a portion, in which a width (2Rp) of the concavo-convex pattern tapers in the width direction, is formed at ends of the concavo-convex pattern in the width direction,
in the forming the sealing part, at least a part of the portion, of which a width is tapered, is included in the overlap area, and
a width (Wp) of the overlap area in the one direction satisfies Equation 1:
Rp/ 2≤ Wp≤ 2 Rp. [Equation 1].
13. The method of manufacturing an electrochemical cell of claim 10 ,
Ws−Wp≥ 1 mm [Equation 2]
Wp≥0.1 mm. [Equation 3]
14. An exterior material that seals an electrode assembly, comprising:
an accommodating part that accommodates the electrode assembly and includes a concavo-convex pattern extended in a width direction of the electrode assembly and that repeats in a longitudinal direction of the electrode assembly; and
a sealing part that is formed by bonding two sealing surfaces along edges of the accommodating part,
wherein the sealing part includes an overlap area having an arc-shaped crease, which is formed by being protruded or recessed when the concavo-convex pattern is formed and then the bonding of the sealing surfaces.