KR-20260067118-A - POUCH TYPE SECONDARY BATTERY AND METHOD OF MANUFACTURING THE SAME

KR20260067118AKR 20260067118 AKR20260067118 AKR 20260067118AKR-20260067118-A

Abstract

A pouch-type secondary battery according to embodiments of the present disclosure comprises an electrode assembly, a pouch sealing the electrode assembly, and an electrode lead. The electrode assembly comprises electrode tabs and a plurality of electrodes that are repeatedly stacked. The pouch comprises a receiving portion for receiving the electrode assembly, a first sealing portion formed at one end in the longitudinal direction relative to the receiving portion, a second sealing portion formed at one end in the width direction relative to the receiving portion, and an insulating pattern extending along the entire length of the first sealing portion, attached to the inner surface of the first sealing portion, and not overlapping with the receiving portion. The electrode lead overlaps with the insulating pattern at the first sealing portion of the pouch and is fused with the electrode tab.

Inventors

정수민
김지형
김태형
문신영
정보라

Assignees

에스케이온 주식회사

Dates

Publication Date: 20260512
Application Date: 20241105

Claims (16)

An electrode assembly comprising a plurality of electrodes that are repeatedly stacked and include electrode tabs; Sealing the above electrode assembly, A receiving portion in which the above electrode assembly is received; A first sealing portion formed at one end in the longitudinal direction with respect to the above-mentioned receiving portion; A second sealing portion formed at one end in the width direction with respect to the above-mentioned receiving portion; A pouch including an insulating pattern that extends over the entire length of the first sealing portion, is attached to the inner surface of the first sealing portion, and does not overlap with the receiving portion; and A pouch-type secondary battery comprising an electrode lead that overlaps with the insulation pattern and is fused with the electrode tab at the first sealing portion of the pouch.
A pouch-type secondary battery according to claim 1, wherein a fused portion of the electrode lead and the electrode tab is formed in the first sealing portion, and the fused portion overlaps with the insulation pattern.
A pouch-type secondary battery according to claim 2, wherein the width of the insulation pattern is greater than the width of the fused portion.
In claim 2, the electrode tab comprises a positive electrode tab and a negative electrode tab, and the electrode lead comprises a positive lead and a negative lead, and The above-mentioned fusion portion includes an anode fusion portion in which the anode lead and the anode tab are fused, and a cathode fusion portion in which the cathode lead and the cathode tab are fused. A pouch-type secondary battery in which the insulation pattern extends continuously across the anode fusion portion and the cathode fusion portion.
A pouch-type secondary battery according to claim 1, wherein the end of the insulating pattern is included in the intersection area of the first sealing portion and the second sealing portion.
A pouch-type secondary battery according to claim 1, wherein the pouch comprises a folding portion formed at the other end in the width direction, and the pouch comprises a first pouch portion and a second pouch portion that cover the upper and lower surfaces of the electrode assembly, respectively, by the folding portion.
A pouch-type secondary battery according to claim 6, wherein the insulation pattern comprises a first insulation pattern included in the first pouch portion and a second insulation pattern included in the second pouch portion.
A pouch-type secondary battery according to claim 7, wherein a fusion portion of the electrode lead and the electrode tab is formed in the first sealing portion, and the fusion portion is disposed between the first insulation pattern and the second insulation pattern.
A pouch-type secondary battery according to claim 7, wherein the first insulation pattern and the second insulation pattern are in contact with each other at the first sealing portion.
In claim 1, the electrode lead protrudes outward from the outer surface of the first sealing portion, and The above insulation pattern is exposed to the outer surface of the first sealing portion, in a pouch-type secondary battery.
A pouch-type secondary battery according to claim 1, wherein the insulating pattern comprises at least one insulating polymer selected from the group consisting of polyethylene (PE), polyacetylene (PA), polycarbonate (PC), polyimide (PI), polyethylene terephthalate (PET), and polypropylene (PP).
A step of preparing a pouch sheet comprising a pair of receiving portions spaced apart in the width direction with a folding portion in between; A step of forming preliminary cut portions at each of the two ends of the pouch sheet in the width direction; A step of forming an insulating pattern on the portion between the receiving portion and the preliminary cutting portion of the pouch sheet; A step of forming a pouch by removing both ends of the pouch sheet using the above-mentioned preliminary cutting portion; A step of accommodating an electrode assembly in the receiving portion of the pouch using the folding portion; and A method for manufacturing a pouch-type secondary battery, comprising the step of sealing a pouch containing the electrode assembly such that the insulation pattern is included in the sealing portion.
In claim 12, the pouch sheet comprises a gas collecting portion spaced longitudinally from the receiving portion, and A method for manufacturing a pouch-type secondary battery, wherein the insulation pattern extends adjacently along the length direction together with the receiving portion and the gas collection portion.
A method for manufacturing a pouch-type secondary battery according to claim 13, further comprising the step of removing the gas collection portion after the step of sealing the pouch.
In claim 12, the receiving portion includes a first receiving portion and a second receiving portion adjacent to each other with the folding portion in between in the width direction, and A method for manufacturing a pouch-type secondary battery, wherein the step of forming the insulation pattern comprises forming a first insulation pattern between the first receiving portion and the preliminary cutting portion, and forming a second insulation pattern between the second receiving portion and the preliminary cutting portion.
A method for manufacturing a pouch-type secondary battery according to claim 15, wherein the step of sealing the pouch comprises sealing so that the first insulation pattern and the second insulation pattern come into contact.

Description

Pouch-type secondary battery and method of manufacturing the same The present disclosure relates to a pouch-type secondary battery and a method for manufacturing the same. Rechargeable batteries are batteries capable of repeated charging and discharging, and with the advancement of the information and communication and display industries, they are widely applied as power sources for portable electronic communication devices such as camcorders, mobile phones, and laptop PCs. Furthermore, recently, battery packs containing rechargeable batteries are being developed and applied as power sources for eco-friendly vehicles, such as hybrid cars. Examples of secondary batteries include lithium-ion batteries, nickel-cadmium batteries, and nickel-hydrogen batteries; among these, lithium-ion batteries are being actively developed and applied due to their high operating voltage and energy density per unit weight, as well as advantages in charging speed and weight reduction. For example, a lithium secondary battery may include an electrode assembly comprising a positive electrode, a negative electrode, and a separator, and an electrolyte impregnating the electrode assembly. The lithium secondary battery may further include an outer casing, for example, in the form of a pouch, that accommodates the electrode assembly and the electrolyte. In the process of housing an electrode assembly inside the pouch-shaped outer material and sealing the edges of the outer material, corrosion of the pouch or insulation failure may occur due to damage to the pouch. FIGS. 1 and FIGS. 2 are schematic plan views showing pouch-type secondary batteries according to exemplary embodiments. FIG. 3 is a schematic cross-sectional view showing a pouch-type secondary battery according to exemplary embodiments. Figure 4 is an enlarged cross-sectional view of area A of Figure 3. FIG. 5 is a process flow diagram for explaining a method for manufacturing a pouch-type secondary battery according to exemplary embodiments. FIGS. 6 to 10 are schematic plan views showing pouch-type secondary batteries manufactured according to exemplary embodiments. The embodiments of the present disclosure provide a pouch-type secondary battery having improved mechanical reliability and stability. The embodiments of the present disclosure provide a method for manufacturing a pouch-type secondary battery having improved mechanical reliability and stability. Embodiments of the present disclosure will be described in more detail below with reference to the drawings. However, the following drawings attached to this specification are intended to illustrate preferred embodiments of the present disclosure and serve to further enhance understanding of the technical concept of the present disclosure together with the content of the aforementioned disclosure; therefore, the present disclosure should not be interpreted as being limited only to the matters described in such drawings. In this specification, terms indicating space/location such as "lower," "upper," "below," "upper," "upper surface," and "lower surface" are used in a relative sense to distinguish components and do not limit the absolute order or location. FIGS. 1 and 2 are schematic plan views illustrating a pouch-type secondary battery according to exemplary embodiments. FIG. 3 is a schematic cross-sectional view illustrating a pouch-type secondary battery according to exemplary embodiments. For example, FIG. 3 may be a cross-sectional view cut along the line I-I' of FIG. 2. In FIGS. 1 to 3, two directions that are parallel to the upper surface of the pouch-type secondary battery or pouch (100) and intersect each other are defined as the first direction and the second direction. For example, the first direction and the second direction may intersect perpendicularly to each other. A direction perpendicular to the upper surface of the pouch (100) is defined as the third direction. For example, the first direction may correspond to the length direction of the pouch (100), the second direction to the width direction of the pouch (100), and the third direction to the thickness direction of the pouch (100). The definition of the directions may be applied in the same way in the remaining drawings. Referring to FIGS. 1 and 2, a pouch-type secondary battery includes an electrode assembly (50) and a pouch (100) that seals the electrode assembly (50). The pouch (100) includes a receiving portion (110) in which an electrode assembly (50) is received, a sealing portion (120) formed at one end of the pouch (100), and an insulating pattern (130). For example, the pouch (100) may include a folding portion (150) formed at the other end in the width direction (e.g., the second direction). For example, the electrode assembly (50) can be accommodated in the receiving portion (110) of the pouch (100) using the folding portion (150), and the electrode assembly (50) can be accommodated by sealing the outer surface of the pouch (100). The pouch