US-12626979-B2 - Battery cell

US12626979B2US 12626979 B2US12626979 B2US 12626979B2US-12626979-B2

Abstract

A battery cell includes a case having an accommodating space, an electrode assembly including an anode, a cathode, and a separator accommodated in the accommodating space, a first sealing portion formed outside the accommodating space in the case, and sealing the case, and a second sealing portion including a region of the case present outside of the first sealing portion, positioned farther away from the accommodating space than the first sealing portion, and sealing the case. The first sealing portion is formed to be inclined between the accommodating space and the second sealing portion.

Inventors

Jong Hyeok Lee
Hyun Ji Kim
Yoon Ji JO
Chang Mook Hwang

Assignees

SK ON CO., LTD.

Dates

Publication Date: 20260512
Application Date: 20221111
Priority Date: 20211130

Claims (7)

1 . A battery cell comprising: a case having an accommodating space; an electrode assembly including an anode, a cathode, and a separator accommodated in the accommodating space; a first sealing portion formed outside the accommodating space in the case, and sealing the case; and a second sealing portion including a region of the case present outside of the first sealing portion, positioned farther away from the accommodating space than the first sealing portion, and sealing the case, wherein the first sealing portion is formed to be inclined between the accommodating space and the second sealing portion, wherein the electrode assembly includes: an anode tab connected to the anode, and drawn out of the case; and a cathode tab connected to the cathode, and drawn out of the case, and the first sealing portion and the second sealing portion are formed in a region from which the anode tab and the cathode tab are drawn out, wherein the first sealing portion seals a region in which the case does not oppose the anode tab and the cathode tab, and the battery cell further comprising an unbonded region disposed toward the accommodating space on an inner side of the first sealing portion and not overlapping with an edge of the case.
2 . The battery cell of claim 1 , wherein the second sealing portion seals, with different sealing forces, a region in which the case opposes the anode tab and the cathode tab, and the region in which the case does not oppose the anode tab and the cathode tab, and wherein the case is bonded such that the region opposing the anode tab and the cathode tab and the region not opposing the anode tab and the cathode tab are bonded with different sealing forces.
3 . The battery cell of claim 2 , wherein the first sealing portion includes: a first inclined sealing portion formed to be inclined between the second sealing portion and the accommodating space; and a second inclined sealing portion spaced apart from the first inclined sealing portion with the anode tab or the cathode tab interposed therebetween, and formed to be inclined between the second sealing portion and the accommodating space.
4 . The battery cell of claim 3 , wherein the second sealing portion seals, with stronger sealing force, the region in which the case opposes the anode tab and the cathode tab than the region in which the case does not oppose the anode tab and the cathode tab, and wherein the case is bonded such that a region opposing the anode tab and the cathode tab is bonded with stronger sealing force than a region not opposing the anode tab and the cathode tab, wherein the first inclined sealing portion and the second inclined sealing portion are inclined in different directions.
5 . The battery cell of claim 3 , wherein the second sealing portion seals, with stronger sealing force, the region in which the case does not oppose the anode tab and the cathode tab than the region in which the case oppose the anode tab and the cathode tab, and wherein the case is bonded such that a region not opposing the anode tab and the cathode tab is bonded with stronger sealing force than a region opposing the anode tab and the cathode tab, wherein the first inclined sealing portion and the second inclined sealing portion are provided in plural, wherein the first inclined sealing portion and the second inclined sealing portion are inclined in different directions.
6 . The battery cell of claim 3 , wherein the first inclined sealing portion and the second inclined sealing portion are linearly inclined.
7 . The battery cell of claim 3 , wherein the first inclined sealing portion and the second inclined sealing portion are non-linearly inclined.

Description

CROSS-REFERENCE TO RELATED APPLICATION(S) This application claims benefit of priority to Korean Patent Application No. 10-2021-0169059 filed on Nov. 30, 2021 in the Korean Intellectual Property Office, the disclosure of which is incorporated herein by reference in its entirety. BACKGROUND 1. Field The present disclosure relates to a battery cell. 2. Description of Related Art A battery cell, a battery capable of being charged and discharged, has a vast application range, from relatively small portable electronic devices to mid- to large-sized automobiles and power storage devices. The battery cell may have a form in which an anode, a cathode, and a separator stack are disposed in a case, and sealing is performed by filling an electrolyte. The battery cell case may have various shapes, such as a pouch, a rectangular shape, a circular shape, and the like. In the case of such a battery cell, gas caused by the electrolyte may be generated therein in the process of repeating charging and discharging. The gas is accommodated in the case. When pressure thereof is above a certain level, a sealing portion of the case may be unsealed, and the gas may be discharged to the outside of the case. Accordingly, a timing of unsealing the case, a position in which the case is first unsealed, and a shape of an unsealed portion of the case may be controlled by a method of adjusting the pressure of the gas in the case. Related Art 1: KR 10-1546545 B1 (Aug. 17, 2015) SUMMARY An aspect of the present disclosure is to increase a gas accommodating capacity of a battery cell case and to delay unsealing of the battery cell case by gas. Another aspect of the present disclosure is to adjust a discharge direction of gas present in a battery cell case. According to an aspect of the present disclosure, there is provided a battery cell including a case having an accommodating space, an electrode assembly including an anode, a cathode, and a separator accommodated in the accommodating space, a first sealing portion formed outside the accommodating space in the case, and sealing the case, and a second sealing portion including a region of the case present outside of the first sealing portion, positioned farther away from the accommodating space than the first sealing portion, and sealing the case. The first sealing portion may be formed to be inclined between the accommodating space and the second sealing portion. The electrode assembly may include an anode tab connected to the anode, and drawn out of the case, and a cathode tab connected to the cathode, and drawn out of the case. The first sealing portion and the second sealing portion may be formed in a region from which the anode tab and the cathode tab are drawn out. The first sealing portion may seal a region in which the case does not oppose the anode tab and the cathode tab. The second sealing portion may seal, with different forces, a region in which the case opposes the anode tab and the cathode tab, and the region in which the case does not oppose the anode tab and the cathode tab. The first sealing portion may include a first inclined sealing portion formed to be inclined between the second sealing portion and the accommodating space, and a second inclined sealing portion spaced apart from the first inclined sealing portion with the anode tab or the cathode tab interposed therebetween, and formed to be inclined between the second sealing portion and the accommodating space. The second sealing portion may seal, with stronger force, the region in which the case opposes the anode tab and the cathode tab than the region in which the case does not oppose the anode tab and the cathode tab. The first inclined sealing portion and the second inclined sealing portion may be inclined in different directions. The second sealing portion may seal, with stronger force, the region in which the case opposes the anode tab and the cathode tab than the region in which the case does not oppose the anode tab and the cathode tab. The first inclined sealing portion and the second inclined sealing portion may be provided in plural. The first inclined sealing portion and the second inclined sealing portion may be inclined in different directions. The first inclined sealing portion and the second inclined sealing portion may be linearly inclined. The first inclined sealing portion and the second inclined sealing portion may be non-linearly inclined. According to the present disclosure, a gas accommodating capacity of a battery cell case may be increased, and a point in time at which the battery cell case is unsealed by gas may be delayed. In addition, according to the present disclosure, a discharge direction of gas present in a battery cell case may be adjusted. BRIEF DESCRIPTION OF DRAWINGS The above and other aspects, features, and advantages of the present disclosure will be more clearly understood from the following detailed description, taken in conjunction with the accompanying drawings, in which: FIG