EP-4742388-A1 - METHOD AND MOLD FOR SEALING POUCH-TYPE BATTERIES AND POUCH-TYPE BATTERY

EP4742388A1EP 4742388 A1EP4742388 A1EP 4742388A1EP-4742388-A1

Abstract

A method of sealing a pouch-type battery includes: a top sealing operation including sealing an upper region of a sealing part of a pouch above an electrode assembly receiving part thereof; a post-electrolyte-injection sealing operation including sealing the sealing part at one side of the electrode assembly receiving part after injecting an electrolyte into an electrode assembly; and a post-degassing sealing operation including sealing a remaining side of the sealing part at an opposite side of the electrode assembly receiving part after removing gas from the electrode assembly receiving part. In the top sealing operation, a gap between the sealing part and the electrode assembly receiving part is substantially the same both at each upper corner of the electrode assembly receiving part and along the upper region between the upper corners of the electrode assembly receiving part.

Inventors

LEE, JEHYUN
JUNG, CHAN YOON
SONG, HOJIN
JANG, Yoonsoo

Assignees

SAMSUNG SDI CO., LTD.

Dates

Publication Date: 20260513
Application Date: 20250514

Claims (15)

A method of sealing a pouch-type battery, the pouch-type battery comprising a pouch having a sealing part and an electrode assembly receiving part, the method comprising: a top sealing operation comprising sealing an upper region of the sealing part above the electrode assembly receiving part; a post-electrolyte-injection sealing operation comprising sealing a region of the sealing part at one side of the electrode assembly receiving part after injecting an electrolyte into an electrode assembly accommodated in the electrode assembly receiving part; and a post-degassing sealing operation comprising sealing a remaining region of the sealing part at another side opposite to the one side of the electrode assembly receiving part after removing gas from the electrode assembly receiving part, wherein, in the top sealing operation, a gap between the sealing part and the electrode assembly receiving part is substantially the same both at each upper corner of the electrode assembly receiving part and along the upper region between the upper corners of the electrode assembly receiving part.
The method as claimed in claim 1, wherein the top sealing operation is performed by using a top sealing mold, wherein the top sealing mold has a contact part configured to contact the pouch and to apply pressure thereto for sealing the same and a body configured to support the contact part, and wherein the contact part has a curvature formation portion formed at each of both corners thereof.
The method as claimed in claim 2, wherein the curvature formation portion forms a curvature portion at a portion of the sealing part corresponding to the corner of the electrode assembly receiving part such that the gap between the sealing part and the electrode assembly receiving part is substantially the same at the corner of the electrode assembly receiving part and at other regions thereof.
The method as claimed in claim 2 or claim 3, wherein the curvature formation portion has substantially the same radius of curvature as the corner of the electrode assembly receiving part; and, optionally, wherein the contact part has an upper region configured to seal an upper portion of the pouch and two protruding regions protruding downwardly from the upper region to extend around the upper corners of the electrode assembly receiving part, and wherein the curvature formation portion is at the corner of the contact part where each of the protruding regions and the upper region meet.
The method as claimed in any preceding claim, wherein, in the post-electrolyte-injection sealing operation, one side of the electrode assembly receiving part, a side of an auxiliary space of the pouch for electrolyte injection and degassing, and a protruding region protruding to a length from the other upper and lower portions of the electrode assembly receiving part are sealed; and, optionally , wherein, in the post-degassing sealing operation, the other unsealed side of the electrode assembly receiving part is sealed.
A mold for sealing a pouch-type battery, the pouch-type battery comprising a pouch comprising a sealing part and an electrode assembly receiving part, the mold comprising: a contact part configured to contact the pouch and to apply pressure thereto for sealing the sealing part of the pouch; and a body configured to support the contact part, wherein the contact part has a curvature formation portion at each of both corners thereof.
The mold as claimed in claim 6, wherein the curvature formation portion forms a curvature portion at a portion of the sealing part corresponding to each corner of the electrode assembly receiving part such that a gap between the sealing part and the electrode assembly receiving part is substantially the same at the corner of the electrode assembly receiving part and at other regions thereof.
The mold as claimed in claim 6 or claim 7, wherein the curvature formation portion has substantially the same radius of curvature as each corner of the electrode assembly receiving part.
The mold as claimed in any of claims 6 to 8, wherein the contact part comprises an upper region configured to seal an upper portion of the pouch and two protruding regions protruding downwardly from the upper region to extend around upper corners of the electrode assembly receiving part, and wherein the curvature formation portion is at the corner of the contact part where each of the protruding regions and the upper region meet.
A pouch-type battery comprising: an electrode assembly; and a pouch accommodating the electrode assembly, the pouch having a sealing part and an electrode assembly receiving part, the pouch being sealed by a method of sealing a pouch-type battery, the method comprising: a top sealing operation comprising sealing an upper region of the sealing part above the electrode assembly receiving part; a post-electrolyte-injection sealing operation comprising sealing a region of the sealing part at one side of the electrode assembly receiving part after injecting an electrolyte into the electrode assembly; and a post-degassing sealing operation comprising sealing a remaining region of the sealing part at another side opposite to the one side of the electrode assembly receiving part after degassing to remove gas from the electrode assembly receiving part, and wherein, in the top sealing operation, a gap between the sealing part and the electrode assembly receiving part is substantially the same at each upper corner of the electrode assembly receiving part and at the upper region between the upper corners of the electrode assembly receiving part.
The pouch-type battery as claimed in claim 10, wherein the top sealing operation is performed by using a top sealing mold, wherein the top sealing mold has a contact part configured to contact the pouch and to apply pressure thereto for sealing the sealing part and a body configured to support the contact part, and wherein the contact part has a curvature formation portion at each of both corners thereof.
The pouch-type battery as claimed in claim 11, wherein the curvature formation portion forms a curvature portion at a portion of the sealing part corresponding to the corner of the electrode assembly receiving part such that the gap between the sealing part and the electrode assembly receiving part is substantially the same at the corner of the electrode assembly receiving part and at other regions thereof.
The pouch-type battery as claimed in claim 11 or 12, wherein the curvature formation portion has substantially the same radius of curvature as the corner of the electrode assembly receiving part.
The pouch-type battery as claimed in claim 13, wherein the contact part has an upper region configured to seal an upper portion of the pouch and two protruding regions protruding downwardly from the upper region to extend around the upper corners of the electrode assembly receiving part, and wherein the curvature formation portion is at the corner of the contact part where each of the protruding regions and the upper region meet.
The pouch-type battery as claimed in any of claims 11 to 14, wherein the post-electrolyte-injection sealing operation is performed to seal one side of the electrode assembly receiving part, a side of an auxiliary space of the pouch for electrolyte injection and degassing, and a protruding region protruding to a length from the other upper and lower portions of the electrode assembly receiving part; and, optionally, wherein the post-degassing sealing operation is performed to seal the other side of the electrode assembly receiving part.

Description

BACKGROUND 1. Field Aspects of embodiments of the present disclosure relate to a method and mold for sealing pouch-type batteries and a pouch-type battery. 2. Description of the Related Art Different from primary batteries that are not designed to be charged, secondary batteries are designed to be discharged and recharged. Low-capacity secondary batteries are used in small, portable electronic devices, such as smart phones, feature phones, notebook computers, digital cameras, and camcorders, while large-capacity secondary batteries are widely used as power sources for driving motors, such as in hybrid vehicles or electric vehicles, and for power storage. A secondary battery may generally include an electrode assembly including (or consisting of) a positive electrode plate and a negative electrode plate, a case accommodating the electrode assembly, and an electrode terminal connected to the electrode assembly. A pouch-type battery includes an electrode assembly and a pouch that accommodates the electrode assembly. From among conventional pouch cell assembly processes, a sealing process is a process of sealing two pouches (e.g., two pouch halves) by hot pressing. However, if the sealing is insufficiently performed, water may penetrate into pouches, especially in a high-temperature and high-humidity environment, which may cause issues, such as leakage of the pouches, water penetration into cells, or swelling. The above information disclosed in this Background section is for enhancement of understanding of the background of the present disclosure, and therefore, it may contain information that does not constitute the related (or prior) art. SUMMARY Embodiments of the present disclosure are directed to a method and mold for sealing pouch-type batteries that ensures reliable pouch sealing and a pouch-type battery manufactured by using the method and mold. Embodiments of the present disclosure are also directed to a method and mold for sealing pouch-type batteries, which prevent or reduce pouch leakage, water penetration, and swelling phenomena, and a pouch-type battery manufactured by using the method and mold. However, aspects and features of the present disclosure are not limited to those discussed above, and other aspects and features not mentioned herein, will be clearly understood by those skilled in the art from the description of the present disclosure below. According to an embodiment of the present disclosure, a method of sealing a pouch-type battery is provided. The pouch-type battery includes a pouch having a sealing part and an electrode assembly receiving part. The method includes a top sealing operation including sealing an upper region of the sealing part above the electrode assembly receiving part, a post-electrolyte-injection sealing operation including sealing a region of the sealing part at one side of the electrode assembly receiving part (or one side of the sealing part along the electrode assembly receiving part) after injecting an electrolyte into an electrode assembly (accommodated in the electrode assembly receiving part), and a post-degassing sealing operation including sealing a remaining region of the sealing part at (or along) another side opposite to the one side of the electrode assembly receiving part after removing (or degassing to remove) gas from the electrode assembly receiving part. In the top sealing operation, a gap between the sealing part and the electrode assembly receiving part is substantially the same at each upper corner of the electrode assembly receiving part and along (or at) the upper region between the upper corners of the electrode assembly receiving part. The top sealing operation may be performed using a top sealing mold. The top sealing mold may have a contact part configured to contact the pouch and to apply pressure thereto for sealing the sealing part and a body configured to support the contact part. The contact part may have a curvature formation portion at each of both corners thereof. The curvature formation portion may form a curvature portion at a portion of the sealing part corresponding to the corner of the electrode assembly receiving part such that the gap between the sealing part and the electrode assembly receiving part is substantially the same at the corner of the electrode assembly receiving part and at other regions thereof. The curvature formation portion may have substantially the same radius of curvature as the corner of the electrode assembly receiving part. The contact part may have an upper region configured to seal an upper portion of the pouch and two protruding regions protruding downwardly from the upper region to extend around the upper corners of the electrode assembly receiving part. The curvature formation portion may be formed at the corner of the contact part where each of the protruding regions and the upper region meet. The post-electrolyte-injection sealing operation may be performed to seal one side of the sealing part a