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EP-4197750-B1 - SEALING DEVICE FOR SECONDARY BATTERY

EP4197750B1EP 4197750 B1EP4197750 B1EP 4197750B1EP-4197750-B1

Inventors

  • WI, YOON BONG
  • JANG, EUNG JIN
  • PARK, SIN YOUNG
  • KANG, TAE WON
  • PARK, DONG HYEUK

Dates

Publication Date
20260506
Application Date
20210805

Claims (11)

  1. A sealing apparatus (100, 200) for a secondary battery (10), wherein the sealing apparatus (100, 200) is configured to seal a battery case (11), which accommodates an electrode assembly (12) therein, to manufacture the secondary battery (10), wherein the secondary battery (10) comprises an electrode lead (13) which is connected to the electrode assembly (12) and extended to the outside of the battery case (11), and the battery case (11) comprises: a lead sealing portion (P1) in which the electrode lead (13) is located in a pressing direction at an outer circumferential surface (11d); and a case sealing portion (P2) in which only the battery case (11) is located, wherein the sealing apparatus (100, 200) comprises: a pair of sealing blocks (110, 120; 130; 210, 220; 230) which press the outer circumferential surface (11d) of the battery case (11); and a heating unit (140) which is provided in the pair of sealing blocks (110, 120; 130; 210, 220; 230) and configured to heat the pair of sealing blocks (110, 120; 130; 210, 220; 230), wherein the pair of sealing blocks (110, 120; 130; 210, 220; 230) comprise: lead sealing regions (E1, E2) configured to press the lead sealing portion (P1) of the battery case (11); and case sealing regions (C1, C2) configured to press the case sealing portion (P2) of the battery case (11), wherein the heating unit (140) is configured to heat the lead sealing regions (E1, E2) and the case sealing regions (C1, C2) of the pair of sealing blocks (110, 120; 130; 210, 220; 230) at different temperatures.
  2. The sealing apparatus of claim 1, wherein the heating unit (140) performs heating such that the temperatures of the lead sealing regions (E1, E2) are higher than the temperatures of the case sealing regions (C1, C2) in the pair of sealing blocks (110, 120; 130; 210, 220; 230).
  3. The sealing apparatus of claim 2, wherein the heating unit (140) heats the case sealing regions (C1, C2) and the lead sealing regions (E1, E2) of the pair of sealing blocks (110, 120; 130; 210, 220; 230) such that the temperatures of the case sealing portion (P2) and the lead sealing portion (P1) of the battery case (11) become uniform when the battery case (11) is pressed.
  4. The sealing apparatus of any one of claims 1 to 3, wherein the pair of sealing blocks (110, 120; 130; 210, 220; 230) press the lead sealing portion (P1) and the case sealing portion (P2) of the battery case (11) at different pressures.
  5. The sealing apparatus of claim 1, wherein the pair of sealing blocks (110, 120; 130; 210, 220; 230) press the lead sealing portion (P1) of the battery case (11) at a higher pressure than the case sealing portion (P2).
  6. The sealing apparatus of claim 1, wherein the pair of sealing blocks (110, 120; 130; 210, 220; 230) press the lead sealing portion (P1) and the case sealing portion (P2) of the battery case (11) at the same pressure.
  7. The sealing apparatus of claim 1, wherein the heating unit (140) comprises: case sealing heaters (143, 144) located at the case sealing regions (C1, C2) in the pair of sealing blocks (110, 120; 130; 210, 220; 230); and lead sealing heaters (141, 142) located at the lead sealing regions (E1, E2).
  8. The sealing apparatus of claim 1, wherein the pair of sealing blocks (110, 120; 130; 210, 220; 230) comprise an upper sealing block (210) located above the battery case (11) and a lower sealing block (220) located below the battery case (11), each of the upper sealing block (210) and the lower sealing block (220) is formed as a single body, and each of the upper sealing block (210) and the lower sealing block (220) further comprises a heat insulator (270; 271, 272) that blocks heat transfer between the case sealing regions (C1, C2) and the lead sealing regions (E1, E2).
  9. The sealing apparatus of claim 1, wherein the pair of sealing blocks (110, 120; 130; 210, 220; 230) comprise an upper sealing block (110; 210) located above the battery case (11) and a lower sealing block (120; 220) located below the battery case (11), and each of the upper sealing block (110; 210) and the lower sealing block (120; 220) is formed in a shape divided into the lead sealing regions (E1, E2) and the case sealing regions (C1, C2).
  10. The sealing apparatus of claim 9, wherein the upper sealing block (110; 210) comprises an upper case block (111) that forms an upper part (C1) of the case sealing regions (C1, C2) and an upper lead block (112) that forms an upper part (E1) of the lead sealing regions (E1, E2), and the lower sealing block (120; 220) comprises a lower case block (121) that forms a lower part (C2) of the case sealing regions (C1, C2) and a lower lead block (122) that forms a lower part (E2) of the lead sealing regions (E1, E2).
  11. A process of manufacturing a secondary battery through the sealing apparatus (100, 200) of any one of claims 1 to 10.

Description

TECHNICAL FIELD The present invention relates to a sealing apparatus for a secondary battery. BACKGROUND ART Secondary batteries are rechargeable unlike primarily batteries, and also, the possibility of compact size and high capacity is high. Thus, many studies on secondary batteries are being carried out recently. As technology development and demands for mobile devices increase, the demands for secondary batteries as energy sources are rapidly increasing. Secondary batteries are classified into coin type batteries, cylindrical type batteries, prismatic type batteries, and pouch type batteries depending on a shape of a battery case. In such a secondary battery, an electrode assembly mounted to the inside of a battery case is a chargeable and dischargeable power generating element having a structure in which an electrode and a separator are stacked. The electrode assembly may be generally classified into: a jelly-roll type in which a separator is interposed between a positive electrode and a negative electrode, each of which has the form of a sheet coated with an active material, and then wound; a stacked type in which a plurality of positive and negative electrodes are sequentially stacked with separators therebetween; and a stack/folding type in which stacked type unit cells are wound together with a separation film having a long length. Meanwhile, when a secondary battery according to the related art is manufactured, an electrode assembly is accommodated in a pouch. Then, outer circumferential surfaces of the pouch are pressed and heated from the top and bottom sides by a sealing tool, and then sealed. Here, in a sealing portion of the pouch, heat loss occurs due to an electrode lead at a region in which the electrode lead is located between the pouch. Thus, the temperature at the region becomes lower than in a region in which only the pouch is located without the electrode lead. Also, accordingly, the temperature of a portion of the sealing tool, which presses the region of the sealing portion in which the electrode lead is located, becomes locally lower. Thus, since the sealing portion is not sealed at the uniform temperature, it is difficult to ensure the uniform sealing quality. [PRIOR ART DOCUMENTS] (Patent Document 1) Korean Patent Publication No. 10-2014-0015647 KR 2016 0133041 A describes a pouch sealing apparatus for sealing a pouch of a pouch-type secondary battery, comprising: a pair of first sealing blocks for pressurizing and heating a first region of the boundary of the pouch; and a pair of second sealing blocks arranged on one side of the pair of first sealing blocks for pressurizing and heating a second region adjacent to the first region of the boundary of the pouch. The first sealing blocks and the second sealing blocks are made of different materials. The pressure and the temperature for pressurizing and heating each of the first region and the second region are different from each other. DISCLOSURE OF THE INVENTION TECHNICAL PROBLEM One aspect of the present invention is to provide a sealing apparatus for a secondary battery, which is capable of ensuring the uniform sealing quality. TECHNICAL SOLUTION The present invention is defined according to the subject matter of the appended independent claims. Particular embodiments are given by the additional features of the appended dependent claims. A sealing apparatus for a secondary battery according to an embodiment of the present invention is a sealing apparatus for sealing a battery case, which accommodates an electrode assembly therein, to manufacture the secondary battery. The secondary battery comprises an electrode lead which is connected to the electrode assembly and extended to the outside of the battery case, and the battery case comprises: a lead sealing portion in which the electrode lead is located in a pressing direction at an outer circumferential surface; and a case sealing portion in which only the battery case is located. The sealing apparatus comprises: a pair of sealing blocks which press the outer circumferential surface of the battery case; and a heating unit which is provided in the pair of sealing blocks and heat the pair of sealing blocks. The pair of sealing blocks comprise: lead sealing regions configured to press the lead sealing portion of the battery case; and case sealing regions configured to press the case sealing portion of the battery case. The heating unit may heat the lead sealing regions and the case sealing regions of the pair of sealing blocks at different temperatures. Meanwhile, a secondary battery according to an embodiment of the present invention may be manufactured through the sealing apparatus for a secondary battery according to an embodiment of the present invention. ADVANTAGEOUS EFFECTS According to the present invention, the battery case is pressed and heated through the pair of sealing blocks, and the pair of sealing blocks are heated through the heating unit when sealing. The lead sealin