EP-4738561-A2 - POUCH-TYPE SECONDARY BATTERY AND FABRICATING METHOD THEREFOR

EP4738561A2EP 4738561 A2EP4738561 A2EP 4738561A2EP-4738561-A2

Abstract

A pouch type secondary battery is disclosed. One aspect of the present invention provides a pouch type secondary battery including a casing material configured to accommodate an electrode assembly from which electrode tabs are led; and the casing material includes a sealing portion formed on three sides of four sides of the pouch type secondary battery and an close contact portion formed on the remaining one side; and an extending portion protruding perpendicularly with respect to the close contact portion is formed in a portion adjacent to the close contact portion in the sealing portion.

Inventors

KIM, TAE IL
KIM, DONG JU
KIM, SUNG YEOP
KIM, JIN GO
LEE, SEUNG NOH

Assignees

SK On Co., Ltd.

Dates

Publication Date: 20260506
Application Date: 20171220

Claims (13)

A pouch type secondary battery comprising: a casing material configured to accommodate an electrode assembly, wherein the casing material includes a sealing portion formed on three of four sides of the pouch type secondary battery, and a close contact portion formed on one remaining side of the pouch type secondary battery, wherein a concave portion is formed in a longitudinal direction of the close contact portion, wherein the casing material, before accommodating the electrode assembly, is provided with a rounded portion having a convex shape, wherein the rounded portion is brought into contact with at least one side surface of the electrode assembly and is spread along the at least one side surface of the electrode assembly, wherein the concave portion is formed as at least a part of the rounded portion.
The pouch type secondary battery according to claim 1, wherein the casing material includes a plurality of accommodation spaces configured to accommodate the electrode assembly, and wherein the rounded portion is disposed between the plurality of accommodation spaces.
The pouch type secondary battery according to claim 2, wherein the plurality of accommodation spaces comprises two accommodation spaces.
The pouch type secondary battery according to claim 1, wherein the sealing portion comprises extending portions protruding with respect to the close contact portion.
The pouch type secondary battery according to claim 4, wherein the concave portion is positioned between the extending portions.
The pouch type secondary battery according to claim 4, wherein the extending portions are disposed at opposite ends of the close contact portion and are spaced apart from each other.
The pouch type secondary battery according to claim 4, wherein the extending portions protrude in a direction perpendicular to the close contact portion.
The pouch type secondary battery according to claim 1, wherein the casing material includes aluminum or an aluminum alloy.
The pouch type secondary battery according to claim 1, wherein the casing material includes a plurality of accommodation spaces configured to accommodate the electrode assembly and a connection portion located between the plurality of accommodation spaces, and wherein the concave portion is formed as at least a part of the connection portion.
A method of fabricating a pouch type secondary battery, the method comprising: forming a casing material having a rounded portion of a convex shape located between a plurality of accommodation spaces configured to accommodate an electrode assembly; accommodating the electrode assembly in one of the plurality of accommodation spaces; spreading the rounded portion along at least one side surface of the electrode assembly so as to form a close contact portion on one side of the pouch type secondary battery; and forming a sealing portion by bonding the casing material at portions other than the close contact portion; and forming, in the close contact portion, a concave portion extending in a longitudinal direction of the close contact portion; wherein the concave portion is formed as at least a part of the rounded portion.
The method according to claim 10, wherein extending portions are formed in the sealing portion and protrude with respect to the close contact portion.
The method according to claim 10, wherein a press in which a plurality of accommodation spaces and a rounded part of an upwardly convex shape formed at a gap between the accommodation spaces are formed is used to form a shape of the casing material, and the casing material is provided in a sheet form and pressed to the side in which the press is located.
The method according to claim 10, wherein the casing material includes aluminum or an aluminum alloy.

Description

[Technical Field] The present invention relates to a pouch type secondary battery and a method of fabricating the same. [Background Art] As low-carbon green growth is emerging as a global issue around the world, the green energy industry is receiving great attention. Recently, development of electric vehicles or energy storage devices for storing renewable energy have been attracting great attention in dealing with the depletion of fossil fuels and reducing carbon dioxide. Since an electric vehicle is driven by using electric energy as a main power source from a battery, without an engine, an electric vehicle does not generate exhaust gas. Further, since the vehicle is driven by using only electric energy from a battery, energy density of the battery should be high compared to a volume occupied by the battery and a weight of the battery. Accordingly, it has been necessary to develop a technique for generating high energy density in secondary batteries of an electric vehicle. Lately, there is a strong demand for extending the lifespan of such secondary batteries, and there is an increasing need for a technique for maintaining performance of secondary batteries even when the secondary batteries are exposed to high temperatures for a long time. A typical pouch type secondary battery may be formed by wrapping an electrode assembly with a casing material. Here, a sealing portion is formed by sealing an outermost portion of the casing material in which an electrode assembly is accommodated. However, when a secondary battery module is assembled in a state in which the sealing portion protrudes, a total volume of the secondary battery module is increased due to the sealing portion, such that energy density of the secondary battery module may be lowered. [Prior-art Documents] [Patent Documents] Korean Patent Publication No. 10-1520153 (May 07, 2015) [Disclosure] [Technical Problem] Embodiments of the present invention provide a pouch type secondary battery module capable of improving density of a secondary battery module by forming a sealing portion of the pouch type secondary battery module to be smaller and a method of fabricating the same. Embodiments of the present invention provide a pouch type secondary battery module which reduces an increase in volume of a sealing portion formed by attaching a casing material to a secondary battery module and a method of fabricating the same. Embodiments of the present invention provide a pouch type secondary battery module which improves cooling efficiency and a method of fabricating the same. [Technical Solution] One aspect of the present invention provides a pouch type secondary battery including a casing material configured to accommodate an electrode assembly from which electrode tabs are led; and the casing material includes a sealing portion formed on three of four sides of the pouch type secondary battery and includes an close contact portion formed on the one remaining side; and an extending portion protruding perpendicularly with respect to the close contact portion is formed in the sealing portion in a portion adjacent to the close contact portion. A concave portion may be formed in a longitudinal direction of the close contact portion. A plurality of accommodation spaces configured to accommodate the electrode assembly and a rounded portion having an upwardly convex shape located at a gap between the plurality of accommodation spaces may be formed in the casing material before the electrode assembly is accommodated in the casing material, and the concave portion may be at least a part of the rounded portion. The casing material may include aluminum or an aluminum alloy. Another aspect of the present invention provides a method of fabricating a pouch type secondary battery, the method including: providing an electrode assembly at which electrode tabs are connected; forming a casing material on which a rounded portion of an upwardly convex shape is formed at a gap between a plurality of accommodation spaces configured to accommodate an electrode assembly; accommodating the electrode assembly in one of the plurality of accommodation spaces of the casing material so that the electrode tab is led to an outside; forming an close contact portion, which is brought into close contact with at least one side surface of side surfaces of the electrode assembly, on the casing material in a state in which the electrode assembly is accommodated in the accommodation space; forming a sealing portion by bonding the casing material at portions other than the close contact portion; and forming an extending portion protruding perpendicularly with respect to the close contact portion by a predetermined length in the sealing portion at a portion adjacent to the close contact portion. A press in which a plurality of accommodation spaces and a rounded part of an upwardly convex shape formed at a gap between the accommodation spaces are formed may be used to form a shape of the casing mate