CN-116073063-B - Cylindrical secondary battery and method for manufacturing the same

CN116073063BCN 116073063 BCN116073063 BCN 116073063BCN-116073063-B

Abstract

A cylindrical secondary battery and a method for manufacturing the same are provided. The cylindrical secondary battery includes a cylindrical can, an electrode assembly in which a first electrode plate, a second electrode plate, and a separator are wound and received in the can, and a cap assembly insulated from the can and electrically connected to the electrode assembly, and a degassing hole penetrates the cap assembly to communicate with the inside of the can. According to the embodiment, since the degassing function is applied to remove gas generated before the product is transported, deformation of the can and cap assembly can be reduced. Further, it is possible to prevent occurrence of swelling of the electrode assembly due to generation of the internal gas, thereby reducing deterioration of the performance of the secondary battery.

Inventors

GAO CHENGGUI
Tian Bingmen
Xu Genhao
Pu Jiankui
Wen Baoyong
JIN DAKUI
Jin Shenzhong

Assignees

三星SDI株式会社

Dates

Publication Date: 20260512
Application Date: 20221102
Priority Date: 20211102

Claims (8)

1. A cylindrical secondary battery, the cylindrical secondary battery comprising: A cylindrical can; an electrode assembly in which a first electrode plate, a second electrode plate, and a separator are wound and which is accommodated in the can, and A cap assembly insulated from the can and electrically connected to the electrode assembly, and a degassing hole passing through the cap assembly to communicate with the inside of the can, Wherein the cap assembly includes a vent plate coupled to one side of the can, Wherein the exhaust plate includes a first support member, an exhaust part connected to an outer side of the first support member, and a second support member connected to an outer side of the exhaust part, Wherein the second support includes a first region disposed toward the exhaust portion and having a thickness greater than a thickness of the exhaust portion, and a second region having a thickness relatively smaller than the thickness of the first region, and Wherein the degassing holes are defined in the first region.
2. The cylindrical secondary battery according to claim 1, wherein the vent plate includes a recess spaced apart from the degassing hole, and Wherein the cap assembly further comprises: A lower cap plate disposed between the exhaust plate and the electrode assembly to be electrically connected to the electrode assembly, and a plurality of slots passing through the lower cap plate, and And a gasket disposed between the exhaust plate and the can to insulate the exhaust plate and the can from each other.
3. The cylindrical secondary battery according to claim 2, wherein: The first supporting piece is in contact with the lower cover plate; the exhaust portion being integral with the first support and the recess being provided in the exhaust portion, and The second support is integrally formed with the exhaust portion, and is coupled to the can through the gasket interposed between the second support and the can.
4. The cylindrical secondary battery according to claim 3, wherein the lower cap plate has a diameter smaller than that of the vent plate, and a top surface of an edge of the lower cap plate is in close contact with and welded to a portion of a bottom surface of an edge of the vent plate.
5. The cylindrical secondary battery according to claim 4, wherein the cap assembly further comprises a resin pin or a rubber pin which is press-fitted into the degassing hole to close the degassing hole after being assembled with the can.
6. The cylindrical secondary battery according to claim 5, wherein the cap assembly further comprises a sealing member that closes the degassing hole after removing the resin pin or the rubber pin when gas is generated inside the can.
7. The cylindrical secondary battery according to claim 6, wherein the sealing member comprises a press-fit ball or a press-fit resin, or is coupled to the degassing hole in a male and female structure.
8. A method for manufacturing a cylindrical secondary battery, the method comprising: Accommodating an electrode assembly in a can to be electrically connected to the can; electrically connecting a cap assembly to the electrode assembly; assembling the cap assembly with the canister; inserting a resin pin or a rubber pin into a hole passing through the cap assembly to close the hole, and After the gas is exhausted by removing the resin pin or the rubber pin when the gas is generated, a sealing member is coupled to the hole passing through the cap assembly to close the hole, Wherein the cap assembly includes a vent plate coupled to one side of the can, Wherein the exhaust plate includes a first support member, an exhaust part connected to an outer side of the first support member, and a second support member connected to an outer side of the exhaust part, Wherein the second support includes a first region disposed toward the exhaust portion and having a thickness greater than a thickness of the exhaust portion, and a second region having a thickness relatively smaller than the thickness of the first region, and Wherein the aperture is defined in the first region.

Description

Cylindrical secondary battery and method for manufacturing the same The present application claims priority and rights of korean patent application No. 10-2021-0148843 filed on the korean intellectual property agency on the date 11 and 2 of 2021, the contents of which are incorporated herein by reference in their entirety. Technical Field Embodiments relate to a cylindrical secondary battery in which an internal gas is removable and a method for manufacturing the same. Background The secondary battery includes a unit cell provided with an electrode assembly and an electrolyte in which the electrode assembly is impregnated, the electrode assembly including a positive electrode, a negative electrode, and a separator interposed between the positive electrode and the negative electrode. The secondary battery may be provided in various appearances such as a cylindrical shape, a prismatic shape, a pouch shape, etc., according to the use. Among them, the cylindrical secondary battery has a structure in which an electrode assembly and an electrolyte are contained inside a cylindrical can and one end of the can is sealed with a cap assembly. Generally, a secondary battery generates gas inside the secondary battery due to repeated charge and discharge and internal chemical factors. There is a limitation in that the cap assembly and the can are deformed due to the generation of gas. The above information disclosed in the art used as the background of the present invention is only for improving the understanding of the background of the present invention and thus may include information that does not constitute the related art. Disclosure of Invention An aspect of the present disclosure provides a cylindrical secondary battery with removable internal gas and a method for manufacturing the same. According to at least one embodiment, a cylindrical secondary battery includes a cylindrical can, an electrode assembly in which a first electrode plate, a second electrode plate, and a separator are wound, and which is accommodated in the can, and a cap assembly insulated from the can and electrically connected to the electrode assembly, and a degassing hole passing through the cap assembly to communicate with the inside of the can. The cap assembly may include a vent plate coupled to one side of the can and spaced apart from the degassing hole to provide a recess, a lower cap plate disposed between the vent plate and the electrode assembly to be electrically connected to the electrode assembly, and a plurality of slots passing through the lower cap plate, and a gasket disposed between the vent plate and the can to insulate the vent plate and the can from each other. The exhaust plate may include a first support member in contact with the lower cover plate, an exhaust part connected to an outer side of the first support member to be integrated with the first support member and provided with a recess therein, and a second support member connected to an outer side of the exhaust part to be integrated with the exhaust part and coupled to the can through a gasket interposed between the second support member and the can. The second support may include a first region disposed toward the exhaust portion and having a thickness greater than that of the exhaust portion, and a second region having a thickness relatively smaller than that of the first region. The degassing holes may be defined in the first region. The lower cover plate may have a diameter smaller than that of the exhaust plate, and a top surface of an edge of the lower cover plate may be in close contact with and welded to a portion of a bottom surface of the edge of the exhaust plate. The cap assembly may further include a resin pin or a rubber pin press-fitted into the degassing hole after being assembled with the can to close the degassing hole. The cap assembly may further include a sealing member to close the degassing hole after removing the resin pin or the rubber pin when gas is generated inside the can. The sealing member may include press-fit balls or press-fit resin, or be coupled to the degassing holes in a male and female configuration. According to another embodiment, a method for manufacturing a cylindrical secondary battery includes accommodating an electrode assembly in a can to be electrically connected to the can, electrically connecting a cap assembly to the electrode assembly, assembling the cap assembly with the can, inserting a resin pin or a rubber pin into a hole through the cap assembly to close the hole, and coupling a sealing member to the hole through the cap assembly to close the hole after exhausting gas by removing the resin pin or the rubber pin when generating gas. Drawings Fig. 1 is a sectional view illustrating a cylindrical secondary battery according to an embodiment; Fig. 2 is a plan view illustrating the cap assembly of fig. 1; Fig. 3 is a plan view illustrating a rear surface of the cap assembly of fig. 1; Fig. 4 is a cross-sectiona