KR20190101589A - Cap assembly for secondary battery - Google Patents

Abstract

Disclosed is a cap assembly for a secondary battery. According to the present invention, the cap assembly for a secondary battery comprises: a cap plate coupled to an opened upper end of a battery case; a pair of electrode terminals including a flange unit connected to an electrode assembly in the battery case and disposed on a lower portion of the cap plate, an insertion unit formed integrally with the flange unit and inserted through a through hole formed in the cap plate, and a coupling member protruding from an upper portion of the cap plate and having a coupling groove, wherein the insertion unit is press-fitted and coupled to the coupling groove; a sealing member closely disposed between a lower surface of the cap plate and an upper surface of the flange unit; a lower insulating body closely disposed between the lower surface of the cap plate and the upper surface of the flange unit; and an upper insulating body molded by insert injection in a state in which the cap plate, the pair of electrode terminal, the sealing member, and the lower insulating body are assembled, and disposed closely between a lower surface of the coupling member and an upper surface of the cap plate and between the through hole and the insertion unit. According to the present invention, it is possible to prevent leakage of an electrolyte, thereby improving sealing performance and safety.

Description

Cap Assembly for Secondary Battery {CAP ASSEMBLY FOR SECONDARY BATTERY}

The present invention relates to a secondary battery cap assembly, and more particularly to a secondary battery cap assembly that can improve the high quality and productivity.

A rechargeable battery is a battery that can be charged and discharged. In the case of a low-capacity battery in which one battery cell is packaged in a pack form, the secondary battery is used in a portable electronic device such as a mobile phone and a camcorder. In the case of large-capacity batteries, it is widely used as a power source for driving motors of hybrid vehicles.

The secondary battery may be formed in various shapes such as a cylindrical shape and a rectangular shape. The secondary battery may contain an electrode assembly and an electrolyte formed between a positive electrode plate and a negative electrode plate, and a separator may be accommodated in the battery case. Install. The electrode assembly is connected to the electrode terminal and the electrode terminal is exposed to the outside through the cap plate.

The secondary battery may leak electrolyte between the cap plate and the electrode terminal when an external shock such as vibration or drop is applied. That is, the adhesion between the cap plate and the electrode terminal may be weakened due to repeated vibration, drop, or the like, and a gap may be generated between the cap plate and the electrode terminal to leak the electrolyte in the battery case. In this way, when the electrolyte leaks, the battery may be shorted or exploded, and the life of the secondary battery itself may be shortened. Therefore, research is required to prevent leakage of electrolyte solution and improve productivity.

Republic of Korea Patent No. 10-1059664 (August 25, 2011)

Therefore, the technical problem to be solved by the present invention is to prevent the gap between the cap plate and the electrode terminals even when repeated external shocks such as vibration or drop, and also easy to assemble can improve productivity and manufacturing cost It is to provide a cap assembly for a secondary battery that can reduce the.

According to an aspect of the invention, the cap plate coupled to the open top of the battery case; A flange portion connected to an electrode assembly in the battery case and disposed under the cap plate, an insertion portion integrally formed with the flange portion and inserted through a through hole formed in the cap plate, and over the cap plate; A pair of electrode terminals disposed to protrude and having a coupling hole and having a coupling member to which the insertion part is pressed into and coupled to the coupling hole; A sealing member disposed in close contact between the lower surface of the cap plate and the upper surface of the flange portion; A lower insulator disposed in close contact between the lower surface of the cap plate and the upper surface of the flange portion; And insert injection molding in a state where the cap plate, the pair of electrode terminals, the sealing member, and the lower insulator are assembled, between the lower surface of the coupling member and the upper surface of the cap plate, and between the through hole and the insertion portion. A cap assembly for a secondary battery including an upper insulator disposed in close contact may be provided.

The upper insulator may include a first horizontal part disposed in close contact between a lower surface of the coupling member and an upper surface of the cap plate; And a first bent part which is continuous at one end of the first horizontal part and is bent downward and is disposed in close contact between the through hole and the insertion part.

The upper insulator may further include a second bent part which is continuous at the other end of the first horizontal part and is bent upward and wraps around and closes the side of the coupling member.

The upper insulator may further include a second horizontal part which is continuous at the first bent part and is bent in the horizontal direction and is disposed in close contact between the lower surface of the cap plate and the upper surface of the flange part.

The insertion part may include at least one first groove formed on an outer circumferential surface thereof, and the first bent part may include a protrusion formed at one side and engaged with the first groove.

The insertion portion further includes a second groove having a “V” shape formed at an end surface, and after the insertion portion is inserted into the coupling hole, the end portion of the insertion portion is continuously formed in the coupling hole of the coupling member and is stepped upward. Can be riveted to the locking jaw.

The flange portion and the coupling member may have a polygonal shape.

According to an aspect of the invention, the cap plate coupled to the open top of the battery case; An upper insulator formed by insert injection molding so as to be in close contact with an upper surface of the cap plate, and having one side engaged with a through hole formed in the cap plate; A lower insulator inserted into the insert injection molding to be in close contact with a lower surface of the cap plate, and coupled to a locking groove formed at one side of the cap plate upwardly; A flange portion connected to an electrode assembly in the battery case and disposed to be in close contact with a lower surface of the lower insulator, an insertion portion integrally formed with the flange portion and inserted into the through hole of the cap plate, and an upper insulator of the upper insulator. A pair of electrode terminals disposed in close contact with each other to protrude from an upper surface thereof, and having a coupling hole formed therein and having a coupling member to which the insertion part is press-fitted into the coupling hole; And a sealing member disposed in close contact between the lower surface of the cap plate and the upper surface of the flange portion.

The upper insulator may include a first horizontal part disposed in close contact between a lower surface of the coupling member and an upper surface of the cap plate; And a first latching portion of the cap plate which is continuously formed at one end of the first horizontal portion and is bent downwardly and is engaged with the through hole and is formed to be stepped upward and is in close contact with the through hole and the insertion portion. It may include a first bent portion disposed.

The upper insulator may further include a second bent part which is continuous at the other end of the first horizontal part and is bent upward and wraps around and closes the side of the coupling member.

The upper insulator may further include a second horizontal part which is continuous at the first bent part and is bent in the horizontal direction and is disposed in close contact between the lower surface of the cap plate and the upper surface of the flange part.

The insertion part may include at least one first groove formed on an outer circumferential surface thereof, and the first bent part may include a protrusion formed at one side and engaged with the first groove.

The insertion portion further includes a second groove having a “V” shape formed at an end surface, and after the insertion portion is inserted into the coupling hole, the end portion of the insertion portion is continuously formed in the coupling hole of the coupling member and is stepped upward. It may be riveted to the second locking step.

The flange portion and the coupling member may have a polygonal shape.

Embodiments of the present invention can prevent a gap between the cap plate and the electrode terminals even when repeated external shocks such as vibration or drop are applied, thereby preventing leakage of the electrolyte and improving sealing and safety. You can.

In addition, the embodiments of the present invention form an upper insulator and / or a lower insulator by insert injection molding between the cap plate and the electrode terminal in a state in which the cap plate and the electrode terminal are assembled, thereby improving assembling and productivity. Manufacturing cost can be reduced.

1 is a cross-sectional view of a secondary battery according to a first embodiment of the present invention.
2 is a state diagram before assembly of the cap assembly according to the first embodiment of the present invention.
3 is a state diagram after assembling the cap assembly according to the first embodiment of the present invention.
4 is a cross-sectional view of the cap assembly according to the first embodiment of the present invention.
5 is a cross-sectional view of a secondary battery according to a first exemplary embodiment of the present invention.
6 is a state diagram before assembly of the cap assembly according to a second embodiment of the present invention.
7 is a state diagram after assembling the cap assembly according to the second embodiment of the present invention.
8 is a cross-sectional view of a cap assembly according to a second embodiment of the present invention.

In order to fully understand the present invention, the operational advantages of the present invention, and the objects achieved by the practice of the present invention, reference should be made to the accompanying drawings which illustrate preferred embodiments of the present invention and the contents described in the accompanying drawings.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. Like reference numerals in the drawings denote like elements.

Hereinafter, a secondary battery according to a first embodiment of the present invention will be described.

1 is a cross-sectional view of a secondary battery according to a first embodiment of the present invention, FIG. 2 is a state diagram before assembling the cap assembly according to the first embodiment of the present invention, and FIG. 3 is a view according to the first embodiment of the present invention. 4 is a state diagram after assembling the cap assembly, and FIG. 4 is a cross-sectional view of the cap assembly according to the first embodiment of the present invention.

Referring to FIG. 1, the secondary battery 100 according to the first embodiment of the present invention includes an electrode assembly 130, a battery case 110, and a cap assembly 200.

The electrode assembly 130 is formed by winding or overlapping a stack of a first electrode plate 131, a separator 133, and a second electrode plate 135 formed in a thin plate shape or a film shape. The first electrode plate 131 may function as an anode, and the second electrode plate 135 may function as a cathode.

The first electrode plate 131 is formed by applying a first electrode active material such as a transition metal oxide to a first electrode current collector formed of a metal foil such as aluminum, and is a first electrode uncoated region that is not coated with the first electrode active material. Section 132. The first electrode uncoated portion 132 serves as a current flow path between the first electrode plate 131 and the first electrode terminal 230.

The second electrode plate 135 is formed by applying a second electrode active material such as graphite or carbon to a second electrode current collector formed of a metal foil such as nickel or copper, and is a region to which the second electrode active material is not coated. The electrode uncoated portion 136 is included. The second electrode uncoated portion 136 serves as a current flow path between the second electrode plate 135 and the second electrode terminal 240.

The separator 133 is positioned between the first electrode plate 131 and the second electrode plate 135 to prevent shorts and to allow movement of lithium ions.

The separator 133 may be made of a composite film of polyethylene, polypropylene, polyethylene and polypropylene, but the scope of the present invention is not limited thereto.

Both ends of the electrode assembly 130 as described above are connected to the first electrode terminal 230 and the second electrode terminal 240, which will be described later, and the electrode assembly 130 is accommodated in the battery case 110 together with the electrolyte. . Meanwhile, the electrolyte may be ethylene carbonate (EC), polycarbonate (PC: polycarbonate), diethyl carbonate (DEC), ethyl methyl carbonate (EMC), dimethyl carbonate (DMC) Organic solvents such as and the like, and lithium salts such as lithium hexafluorophosphate (LiPF6), boron lithium fluoride (LiBF4), and the like. In addition, electrolyte solution is a liquid, a solid, or a gel state.

When the electrolyte penetrates into the region between the first electrode terminal 230 and the cap assembly 200 or the region between the second electrode terminal 240 and the cap assembly 200, the dielectric breakdown voltage is lowered to lower the first electrode terminal ( 230 may cause an electrical short between the cap assembly 200 or the second electrode terminal 240 and the cap assembly 200.

The battery case 110 is formed of a conductive metal such as aluminum, an aluminum alloy, or nickel plated steel, and includes an electrode assembly 130, a first electrode terminal 230, a second electrode terminal 240, and an electrolyte solution. An upper end (not shown) may be formed in an open hexahedral shape or the like. The inner surface of the battery case 110 is insulated to electrically insulate the electrode assembly 130, the first electrode terminal 230, and the second electrode terminal 240.

The cap assembly 200 is coupled to the open top of the battery case 110.

2 to 4, the cap assembly 200 includes a cap plate 210, a first electrode terminal 230, a second electrode terminal 240, a sealing member 250, a lower insulator 290, and an upper portion. An insulator 270. In the present embodiment, the assembly of the cap plate 210, the first electrode terminal 230, the second electrode terminal 240, the sealing member 250 and the lower insulator 290 is put into the mold and then put into the inserted assembly. The cap assembly 200 is manufactured by injection molding the upper insulator 270 by an insert injection method, and the cap assembly 200 is coupled to the open top of the battery case 110.

The cap plate 210 is coupled to the open top of the battery case 110 to seal the battery case 110. The cap plate 210 may be formed of the same material as the battery case 110.

In addition, the cap plate 210 is formed with an electrolyte injection hole 213 through which the electrolyte is injected and a through hole 211 through which the first electrode terminal 230 and the second electrode terminal 240 to be described later are respectively coupled. In the present embodiment, through holes 211 are formed at both sides of the electrolyte injection hole 213, respectively.

When the electrolyte needs to be filled in the battery case 110, the electrolyte is injected into the battery case 110 through the electrolyte injection hole 213, and then the electrolyte injection hole 213 is opened using the plug 215. Prevent.

The first electrode terminal 230 and the second electrode terminal 240, which are a pair of electrode terminals 230 and 240, are respectively coupled to the through hole 211 formed in the cap plate 210. In the present embodiment, the first electrode terminal 230 may act as a positive electrode and the second electrode terminal 240 may act as a negative electrode, even if the polarities of the first electrode terminal 230 and the second electrode terminal 240 are changed. It's okay.

The first electrode terminal 230 includes a flange portion 231, an insertion portion 233, and a coupling member 236. The second electrode terminal 240 includes a flange portion 241, an insertion portion 243, and a coupling member 246. In the present embodiment, since the first electrode terminal 230 and the second electrode terminal 240 have the same structure, the description of the second electrode terminal 240 is replaced with the description of the first electrode terminal 230 below. Let's do it.

The flange portion 231 is connected to the electrode assembly 130 in the battery case 110 and disposed below the cap plate 210. The insertion part 233 is formed integrally with the flange part 231 and is inserted through the through hole 211 of the cap plate 210. The coupling member 236 is disposed to protrude above the cap plate 210 and the coupling hole 237 is formed so that the insertion portion 233 is press-fitted. 2 to 4, the flange portion 231 and the coupling member 236 are illustrated to have a quadrangular shape, but the scope of the present invention is not limited thereto. The flange portion 231 and the coupling member 236 are not limited thereto. May be formed in a polygonal shape.

In addition, the coupling between the insertion part 233 and the coupling member 236 is coupled to a press fit structure in which the insertion part 233 is press-fitted into the coupling hole 237 of the coupling member 236. Therefore, even when a repeated external shock such as vibration or drop is applied, the insertion part 233 and the coupling member 236 may be prevented from being separated or separated from each other.

In addition, the insertion part 233 may have at least one first recess 234 on an outer circumferential surface thereof. As shown in FIG. 4, a plurality of first recesses 234 may be formed in the height direction on the outer circumferential surface of the insertion part 233. This may prevent the upper insulator 270 from being separated by inserting one side of the upper insulator 270 into the first recess 234 when insert injection molding the upper insulator 270 to be described later. 233 may be prevented from being separated from the coupling member 236. That is, in the process of injection molding the upper insulator 270, a first protrusion 276 is inserted into the first recess 234 to be engaged.

In addition, the insertion portion 233 may further include a second groove 235 having a “V” shape formed at an end surface thereof. The insertion part 233 is inserted into the engaging hole 237 of the coupling member 236 and then inserted into the engaging jaw 238 that is continuously formed in the coupling hole 237 of the coupling member 236 and is stepped upward. This is to rivet the end of 233). That is, after inserting the insertion part 233 into the coupling hole 237, the end portion of the insertion part 233 having the “V” shaped second groove 235 is pressurized and bent to rivet to the locking jaw 238. . As a result, even when repeated external shocks such as vibration or drop are applied, the insertion part 233 and the coupling member 236 may be further prevented from being decoupled or separated from each other.

The sealing member 250 is disposed in close contact between the lower surface of the cap plate 210 and the upper surface of the flange portion 231. The sealing member 250 prevents the electrolyte in the battery case 110 from leaking to the outside. In this embodiment, the sealing member 250 may be formed of a material such as Teflon, silicon, rubber, but the scope of the present invention is not limited thereto. The sealing member 250 is spaced apart from the through hole 211 and has an o-ring shape disposed between the lower surface of the cap plate 210 and the upper surface of the flange portion 231 along the circumference of the through hole 211. Can be formed. In addition, the sealing member 250 is in close contact between the lower surface of the cap plate 210 and the upper surface of the flange portion 231 in a state of being inserted into the insertion hole 232 formed on the upper surface of the flange portion 231.

The upper insulator 270 is disposed in close contact between the bottom surface of the coupling member 236 and the top surface of the cap plate 210 and between the through hole 211 and the insertion portion 233. In the present embodiment, the upper insulator 270 is insert injection molded in a state in which the cap plate 210, the pair of electrode terminals 230 and 240, the sealing member 250, and the lower insulator 290 are assembled. That is, the cap plate 210, the pair of electrode terminals 230 and 240, the sealing member 250, and the lower insulator 290 are put into a mold in an assembled state, and then the lower surface of the coupling member 236 and the cap plate 210 are separated. The upper insulator 270 is formed by injecting an insulating material between the upper surface and between the through hole 211 and the insertion part 233.

Specifically, the upper insulator 270 is continuous and downward from one end of the first horizontal portion 271 and the first horizontal portion 271 disposed in close contact between the lower surface of the coupling member 236 and the upper surface of the cap plate 210. It is formed to be bent to include a first bent portion 275 is disposed in close contact between the through-hole 211 and the insertion portion 233. The first horizontal portion 271 prevents an electrical short between the upper surface of the cap plate 210 and the lower surface of the coupling member 236, and the first bent portion 275 includes the insertion portion 233 and the cap plate 210. Electrical short between the through holes 211 is prevented.

In addition, as described above, one side of the first bent part 275 is engaged with the first recess 234 formed on the outer circumferential surface of the insertion part 233 to prevent the upper insulator 270 from being separated. That is, the first protrusion 276 is injection molded on one side of the first bent portion 275 and inserted into the first recess 234 to be engaged.

In addition, the upper insulator 270 may further include a second bent part 277 which is continuously formed at the other end of the first horizontal part 271 and is bent upward and surrounds the side of the coupling member 236. This is because the second bent portion 277 is formed in a structure surrounding the side of the polygonal coupling member 236 can prevent the coupling member 236 is rotated by an external impact and the charge and discharge pin (not shown) is coupled Damage to the coupling member 236 may be prevented.

In addition, the upper insulator 270 is continuously formed in the first bent portion 275 and bent in the horizontal direction, and is disposed in close contact with the lower surface of the cap plate 210 and the upper surface of the flange portion 231 ( 273) may be further included. The second horizontal portion 273 prevents electrical short between the lower surface of the cap plate 210 and the upper surface of the flange portion 231. The end portion of the second horizontal portion 273 extends in the outward direction of the through hole 211 of the cap plate 210 and is disposed adjacent to the sealing member 250.

The lower insulator 290 is disposed in close contact between the lower surface of the cap plate 210 and the upper surface of the flange portion 231. The lower insulator 290 is disposed in close contact between the lower surface of the cap plate 210 and the upper surface of the flange portion 231 to prevent leakage of the electrolyte solution, and the cap plate 210 and the first electrode terminal 230. Alternatively, electrical short between the second electrode terminals 240 may be prevented.

Specifically, the lower insulator 290 is continuous at one end of the third horizontal portion 291 and the third horizontal portion 291 disposed in close contact between the lower surface of the cap plate 210 and the upper surface of the flange portion 231. It is formed to be bent to include a third bent portion (293) wrapped around the side portion of the flange portion 231.

The third horizontal portion 291 prevents electrical short between the lower surface of the cap plate 210 and the upper surface of the flange portion 231. In addition, the end portion of the third horizontal portion 291 extends toward the center of the through hole 211 of the cap plate 210 and is disposed adjacent to the sealing member 250. And since the third bent portion 293 is formed in a structure surrounding the side of the polygonal flange portion 231 it can be prevented that the flange portion 231 is rotated by an external impact.

In this embodiment, the material of the upper insulator 270 and the lower insulator 290 may be any one of polyphenylene sulfide (PPS), polyperfluoroalkoxy ethylene (PFA), and polypropylene (PP; polryproylene). However, the scope of the present invention is not limited thereto.

Referring to the assembly operation of the cap assembly 200 configured as described above are as follows.

As shown in FIG. 2, a cap plate 210, a first electrode terminal 230, a second electrode terminal 240, and a sealing member 250 are first disposed.

In addition, the lower insulator 290 is disposed in close contact with the lower surface of the cap plate 210 and the sealing member 250 is disposed in the insertion hole 232 of the flange portion 231. Inserted into the through-hole 211 of the 210 and penetrates the end of the insertion portion 233 through the through-hole 211 into the coupling hole 237 of the coupling member 236. Then, the second groove 235 having a “V” shape formed at the end surface of the insertion part 233 is pressed and bent to rivet to the locking step 238 formed at the coupling member 236.

3 and 4, an assembly in which the cap plate 210, the first electrode terminal 230, the second electrode terminal 240, the sealing member 250, and the lower insulator 290 are assembled. The upper insulator 270 is molded into the mold by insert injection into the injected assembly.

The upper insulator 270 is continuously bent downward from one end of the first horizontal portion 271 and the first horizontal portion 271 disposed in close contact between the lower surface of the coupling member 236 and the upper surface of the cap plate 210. It is formed so as to be continuous at the other end of the first bent portion 275 and the first horizontal portion 271 and the first bent portion 275 and the insertion portion 233 disposed in close contact with the coupling member 236 The second bent portion 277 and the first bent portion 275 surrounding the side of the (275) is formed to be continuous and horizontally bent and disposed in close contact between the lower surface of the cap plate 210 and the upper surface of the flange portion 231 And a second horizontal portion 273 to be formed.

Insert injection molding of the upper insulator 270 with the cap plate 210, the first electrode terminal 230, the second electrode terminal 240, the sealing member 250, and the lower insulator 290 assembled as described above. The assembly and productivity can be improved, and the manufacturing cost can be reduced. In addition, the upper insulator 270 may be disposed in close contact between the lower surface of the coupling member 236 and the upper surface of the cap plate 210 and between the first through hole 211 and the insertion portion 233 to improve sealing and safety. And leakage of electrolyte can be prevented efficiently.

Hereinafter, a secondary battery according to a second embodiment of the present invention will be described.

5 is a cross-sectional view of a secondary battery according to a first embodiment of the present invention, FIG. 6 is a state diagram before assembling the cap assembly according to the second embodiment of the present invention, and FIG. 7 is a second embodiment of the present invention. After the assembly of the cap assembly is a state diagram, Figure 8 is a cross-sectional view of the cap assembly according to a second embodiment of the present invention.

Referring to FIG. 5, the secondary battery 100a according to the second embodiment of the present invention includes an electrode assembly 130a, a battery case 110a, and a cap assembly 200a.

Since the electrode assembly 130a and the battery case 110a according to the second embodiment of the present invention are the same as the electrode assembly 130 and the battery case 110 according to the first embodiment of the present invention, a detailed description thereof is omitted. Let's do it. Hereinafter, the cap assembly 200a which is a difference will be described.

The cap assembly 200a according to the present embodiment is coupled to an open upper end of the battery case 110a.

6 to 8, the cap assembly 200a includes a cap plate 210a, a first electrode terminal 230a, a second electrode terminal 240a, a sealing member 250a, an upper insulator 270a, and a lower portion. An insulator 290a. In the present embodiment, after inserting the cap plate 210a into the mold, the upper insulator 270a and the lower insulator 290a are injection molded into the cap plate 210a by the insert injection method, and the first electrode terminal 230a and the first electrode terminal 230a are formed. The two electrode terminals 240a and the sealing member 250a are assembled and manufactured, and the cap assembly 200a is coupled to the open upper end of the battery case 110a.

The cap plate 210a is coupled to an open upper end of the battery case 110a to seal the battery case 110a. The cap plate 210a may be formed of the same material as the battery case 110a.

In addition, the cap plate 210a is formed with a through hole 211a through which an electrolyte injection hole 213a into which an electrolyte solution is injected, and a first electrode terminal 230a and a second electrode terminal 240a to be described later. In the present embodiment, through holes 211a are formed at both sides of the electrolyte injection hole 213a, respectively.

When it is necessary to fill the electrolyte in the battery case 110a, the electrolyte is injected into the battery case 110a through the electrolyte injection hole 213a, and then the electrolyte injection hole 213a is opened using the plug 215a. Prevent.

The first electrode terminal 230a and the second electrode terminal 240a are respectively coupled to the through hole 211a formed in the cap plate 210a. In the present exemplary embodiment, the first electrode terminal 230a may act as an anode and the second electrode terminal 240a may act as a cathode, even if the polarities of the first electrode terminal 230a and the second electrode terminal 240a are changed. It's okay.

The first electrode terminal 230a includes a flange portion 231a, an insertion portion 233a, and a coupling member 236a. The second electrode terminal 240a includes a flange portion 241a, an insertion portion 243a, and a coupling member 246a. In the present embodiment, since the first electrode terminal 230a and the second electrode terminal 240a have the same structure, the description of the second electrode terminal 240a is replaced with the description of the first electrode terminal 230a. Let's do it.

The flange portion 231a is connected to the electrode assembly 130a in the battery case 110a and disposed below the cap plate 210a. The insertion portion 233a is formed integrally with the flange portion 231a and is inserted through the through hole 211a of the cap plate 210a. The coupling member 236a is disposed to protrude from the top of the cap plate 210a, and the coupling hole 237a is formed so that the insertion part 233a is press-fitted and coupled. 6 to 8, the flange portion 231a and the coupling member 236a are illustrated to have a quadrangular shape, but the scope of the present invention is not limited thereto. The flange portion 231a and the coupling member 236a are not limited thereto. May be formed in a polygonal shape.

In addition, the insertion portion 233a and the coupling member 236a are coupled to each other by a press fit structure in which the insertion portion 233a is press-fitted into the coupling hole 237a of the coupling member 236a. Therefore, even when a repeated external shock such as vibration or drop is applied, the insertion part 233a and the coupling member 236a may be prevented from being released or separated from each other.

In addition, the insertion portion 233a may include at least one first recess 234a on an outer circumferential surface thereof. As illustrated in FIG. 8, a plurality of first recesses 234a may be formed in the height direction on the outer circumferential surface of the insertion portion 233a. This may prevent the upper insulator 270a from being separated by allowing one side of the upper insulator 270a to be described later to be engaged with the first recess 234a, and the insertion part 233a may be separated from the coupling member 236a. Can be prevented. That is, in the process of injection molding the upper insulator 270a, a first protrusion 276a is inserted into the first recess 234a to be engaged.

In addition, the insertion portion 233a may further include a second recess 235a having a “V” shape formed at an end surface thereof. The insertion part 233a is inserted into the coupling hole 237a of the coupling member 236a and then inserted into the engaging jaw 238a which is continuously formed in the coupling hole 237a of the coupling member 236a and stepped upward. This is to rivet the end of 233a). That is, after inserting the insertion portion 233a into the coupling hole 237a, the end portion of the insertion portion 233a having the “V” shaped second groove 235a is pressed and bent to rivet to the locking step 238a. . As a result, even when repeated external shocks such as vibration or drop are applied, the insertion part 233a and the coupling member 236a may be further prevented from being decoupled or separated from each other.

The sealing member 250a is disposed in close contact between the lower surface of the cap plate 210a and the upper surface of the flange portion 231a. The sealing member 250a prevents the electrolyte in the battery case 110a from leaking to the outside. In the present embodiment, the sealing member 250a may be formed of a material such as Teflon, silicon, or rubber, but the scope of the present invention is not limited thereto. The sealing member 250a is spaced apart from the through hole 211a and has an o-ring shape disposed between the lower surface of the cap plate 210a and the upper surface of the flange portion 231a along the circumference of the through hole 211a. Can be formed. In addition, the sealing member 250a is in close contact with the lower surface of the cap plate 210a and the upper surface of the flange portion 231a in a state of being inserted into the insertion hole 232a formed on the upper surface of the flange portion 231a.

The upper insulator 270a is disposed to be in close contact with the upper surface of the cap plate 210a and one side thereof is engaged with the through hole 211a formed in the cap plate 210a. In the present embodiment, the upper insulator 270a is insert injection molded on the top surface of the cap plate 210a. That is, after the cap plate 210a is inserted into the mold, the upper insulator 270a is formed by injecting an insulating material into the upper surface of the cap plate 210a.

Specifically, the upper insulator 270a is continuous and downward from one end of the first horizontal portion 271a and the first horizontal portion 271a disposed in close contact between the lower surface of the coupling member 236a and the upper surface of the cap plate 210a. It is formed to be bent to the first engaging jaw (219a) of the cap plate (210a) is formed to be continuous to the through hole (211a) and is stepped upward and closely contact between the through hole (211a) and the insertion portion (233a) The first bent portion 275a is disposed. The first horizontal portion 271a prevents electrical short between the upper surface of the cap plate 210a and the lower surface of the coupling member 236a, and the first bent portion 275a includes the insertion portion 233a and the cap plate 210a. Electrical short between the through holes 211a.

In addition, as described above, in order to prevent the upper insulator 270a from being separated, insert injection molding is performed such that one side of the first bent part 275a is engaged with the first groove 234a formed on the outer circumferential surface of the insertion part 233a. . That is, the first protrusion 276a is injection molded on one side of the first bent portion 275a to be inserted into the first recess 234a and engaged.

In addition, in insert-molding the upper insulator 270a to the upper surface of the cap plate 210a, the through hole 211a is formed on the upper surface of the cap plate 210a so that the upper insulator 270a can be fixed to the upper surface of the cap plate 210a. ) And a first locking step (219a) formed to be stepped upwardly and is formed, the upper insulator (270a) insert injection molding so that the other side of the first bent portion (275a) is engaged with the first locking step (219a) do.

In addition, the upper insulator 270a may further include a second bent part 277a that is continuously formed at the other end of the first horizontal part 271a and is bent upward and closes and surrounds the side of the coupling member 236a. This is because the second bent portion (277a) is formed in a structure surrounding the side of the polygonal coupling member 236a can prevent the coupling member 236a is rotated by an external impact and the charge and discharge pin (not shown) is coupled Damage to the coupling member 236a may be prevented.

In addition, the upper insulator 270a is formed to be continuous and bent in the horizontal direction at the first bent portion 275a and is disposed in close contact with the bottom surface of the cap plate 210a and the top surface of the flange portion 231a ( 273a) may be further included. The second horizontal portion 273a prevents electrical short between the lower surface of the cap plate 210a and the upper surface of the flange portion 231a. The end of the second horizontal portion 273a extends in the outward direction of the through hole 211a of the cap plate 210a and is disposed adjacent to the sealing member 250a.

The lower insulator 290a is disposed in close contact between the lower surface of the cap plate 210a and the upper surface of the flange portion 231a. The lower insulator 290a is disposed in close contact between the lower surface of the cap plate 210a and the upper surface of the flange portion 231a to prevent leakage of the electrolyte solution, and the cap plate 210a and the first electrode terminal 230a and //. Alternatively, an electrical short between the second electrode terminals 240a may be prevented.

In the present embodiment, the lower insulator 290a is insert injection molded on the lower surface of the cap plate 210a. That is, after the cap plate 210a is inserted into the mold, an insulating material is injected into the upper surface of the cap plate 210a to form a lower insulator 290a. In this case, the lower insulator 290a may be insert injection molded into the upper insulator 270a at the same time in the mold, but is not limited thereto. The lower insulator 290a may be formed after the upper insulator 270a is formed. ) May be formed after the upper insulator 270a is formed.

In order to form the lower insulator 290a on the lower surface of the cap plate 210a, a locking groove 217a is formed on the lower surface of the cap plate 210a, and one side of the lower insulator 290a is the locking groove 217a. To be engaged.

In detail, the lower insulator 290a is continuous and downward from one end of the third horizontal portion 291a and the third horizontal portion 291a disposed in close contact between the lower surface of the cap plate 210a and the upper surface of the flange portion 231a. It is formed to be bent to include a third bent portion (293a) is wrapped close to the side of the flange portion (231a).

The third horizontal portion 291a prevents an electrical short between the lower surface of the cap plate 210a and the upper surface of the flange portion 231a. In addition, the end portion of the third horizontal portion 291a extends toward the center of the through hole 211a of the cap plate 210a and is disposed adjacent to the sealing member 250a. In the process of injection molding the third horizontal portion 291a, the second protrusion 292a is inserted into and engaged with the locking groove 217a formed on the lower surface of the cap plate 210a on the upper surface of the third horizontal portion 291a. Is formed.

And since the third bent portion 293a is formed in a structure surrounding the side of the polygonal flange portion 231a, it is possible to prevent the flange portion 231a from being rotated by an external impact.

In the present embodiment, the material of the upper insulator 270a and the lower insulator 290a may be any one of polyphenylene sulfide (PPS), polyperfluoroalkoxyethylene (PFA), and polypropylene (PP; polryproylene). However, the scope of the present invention is not limited thereto.

Referring to the assembly operation of the cap assembly (200a) configured as described above are as follows.

As shown in FIG. 6, the cap plate 210a is first introduced into a mold, and the upper insulator 270a is injection molded on the upper surface of the cap plate 210a by an insert injection method, and an insert is formed on the lower surface of the cap plate 210a. The lower insulator 290a is injection molded in an injection method. In the present embodiment, the upper insulator 270a and the lower insulator 290a may be simultaneously formed on the upper and lower surfaces of the cap plate 210a, and the upper insulator 270a and the lower insulator 290a may be sequentially formed. .

The upper insulator 270a is continuous and bent downward at one end of the first horizontal portion 271a and the first horizontal portion 271a disposed in close contact between the lower surface of the coupling member 236a and the upper surface of the cap plate 210a. The first bent portion 275a which is formed to be connected to the first latching jaw 219a which is continuously formed in the through hole 211a and is stepped upward and is disposed in close contact between the through hole 211a and the insertion portion 233a. ) Is continuously and horizontally bent at the other end of the first horizontal portion 271a and is continuously and horizontally formed at the second bent portion 277a and the first bent portion 275a which surround and close the sides of the coupling member 236a. The second horizontal portion 273a is formed to be bent in a direction and is disposed in close contact between the lower surface of the cap plate 210a and the upper surface of the flange portion 231a.

Insert injection molding the upper insulator 270a on the upper surface of the cap plate 210a as described above can improve the assembly and productivity, and can also reduce the manufacturing cost. In addition, the upper insulator 270a may be disposed in close contact between the lower surface of the coupling member 236a and the upper surface of the cap plate 210a and between the first through hole 211a and the insertion portion 233a to improve sealing and safety. And leakage of electrolyte can be prevented efficiently.

The lower insulator 290a is continuous and downward from one end of the third horizontal portion 291a and the third horizontal portion 291a disposed in close contact between the lower surface of the cap plate 210a and the upper surface of the flange portion 231a. It is formed to be bent and includes a third bent portion (293a) that wraps close to the side of the flange portion (231a).

Insert injection molding the lower insulator 290a on the lower surface of the cap plate 210a as described above can improve the assembly and productivity, and can also reduce the manufacturing cost. In addition, the lower insulator 290a may be disposed in close contact between the lower surface of the cap plate 210a and the upper surface of the flange portion 231a to improve sealing and safety and effectively prevent leakage of electrolyte.

The cap plate 210a, the first electrode terminal 230a, the second electrode terminal 240a, and the sealing member 250a, to which the upper insulator 270a and the lower insulator 290a are coupled, are disposed.

As shown in FIGS. 7 and 8, the insertion part 233a is disposed in the insertion hole 232a of the flange part 231a and the through hole 211a of the cap plate 210a is disposed. ) Is inserted into the coupling hole 237a of the coupling member 236a by inserting the end portion of the insertion portion 233a through the through hole 211a. Then, the second groove 235a having a “V” shape formed at the end surface of the insertion portion 233a is pressed and bent to rivet to the second locking step 238a formed at the coupling member 236a.

As described above, the present invention is not limited to the described embodiments, and various modifications and variations can be made without departing from the spirit and scope of the present invention. Therefore, such modifications or variations will have to be belong to the claims of the present invention.

100, 100a: secondary battery 110, 110a: battery case
130, 130a: electrode assembly 200, 200a: cap assembly
210, 210a: Cap plate 211, 211a: Through hole
213 and 213a: electrolyte injection holes 215 and 215a: plug
217a: locking groove 219a: first locking jaw
230, 230a: first electrode terminal 231, 231a: flange portion
232, 232a: insertion hole 233, 233a: insertion part
234, 234a: first groove 235, 235a: second groove
236, 236a: coupling member 237, 237a: coupling hole
238: jamming jaw 238a: second jamming jaw
240 and 240a: second electrode terminals 241 and 241a: flange portions
243 and 243a: insertion portions 246 and 246a: coupling members
250, 250a: sealing member 270, 270a: upper insulator
271, 271a: first horizontal portion 273, 273a: second horizontal portion
275, 275a: first bent portion 276, 276a: first protrusion
277, 277a: second bent portion 290, 290a: lower insulator
291, 291a: third horizontal portion 292a: second projection
293, 293a: third bend

Claims (14)

A cap plate coupled to the open top of the battery case;
A flange portion connected to an electrode assembly in the battery case and disposed under the cap plate, an insertion portion integrally formed with the flange portion and inserted through a through hole formed in the cap plate, and over the cap plate; A pair of electrode terminals disposed to protrude and having a coupling hole and having a coupling member to which the insertion part is pressed into and coupled to the coupling hole;
A sealing member disposed in close contact between the lower surface of the cap plate and the upper surface of the flange portion;
A lower insulator disposed in close contact between the lower surface of the cap plate and the upper surface of the flange portion; And
Insert injection molding is performed while the cap plate, the pair of electrode terminals, the sealing member, and the lower insulator are assembled to closely contact the lower surface of the coupling member and the upper surface of the cap plate, and between the through hole and the insertion portion. Cap assembly for a secondary battery comprising an upper insulator disposed to be. The method of claim 1,
The upper insulator is,
A first horizontal portion disposed in close contact between the bottom surface of the coupling member and the top surface of the cap plate; And
A secondary battery cap assembly including a first bent portion which is continuous at one end of the first horizontal portion and is bent downward and is disposed in close contact between the through-hole and the insertion portion. The method of claim 2,
The upper insulator is,
A secondary battery cap assembly further comprising a second bent portion which is continuous at the other end of the first horizontal portion and is bent upwardly and wraps close to the side of the coupling member. The method of claim 2,
The upper insulator is,
A secondary battery cap assembly further comprising a second horizontal portion which is continuous in the first bent portion and is bent in a horizontal direction and is disposed in close contact between the lower surface of the cap plate and the upper surface of the flange portion. The method of claim 2,
The insertion portion has at least one first groove formed on the outer circumferential surface,
The first bent portion is formed on one side of the cap assembly for a secondary battery comprising a projection engaging with the first groove. The method of claim 1,
The insertion portion further has a second groove of the "V" shape formed in the end surface,
After the insertion portion is inserted into the coupling hole end portion of the insert portion is a secondary battery cap assembly is riveted to the engaging jaw formed in the stepped upward and continuous to the coupling hole of the coupling member. The method of claim 1,
The flange portion and the coupling member is a secondary battery cap assembly having a polygonal shape. A cap plate coupled to the open top of the battery case;
An upper insulator formed by insert injection molding so as to be in close contact with an upper surface of the cap plate, and having one side engaged with a through hole formed in the cap plate;
A lower insulator inserted into the insert injection molding to be in close contact with a lower surface of the cap plate, and coupled to a locking groove formed at one side of the cap plate upwardly;
A flange portion connected to an electrode assembly in the battery case and disposed to be in close contact with a lower surface of the lower insulator, an insertion portion integrally formed with the flange portion and inserted into the through hole of the cap plate, and an upper insulator of the upper insulator. A pair of electrode terminals disposed in close contact with each other to protrude from an upper surface thereof, and having a coupling hole formed therein and having a coupling member to which the insertion part is press-fitted into the coupling hole; And
And a sealing member disposed in close contact between the lower surface of the cap plate and the upper surface of the flange portion. The method of claim 8,
The upper insulator is,
A first horizontal portion disposed in close contact between the bottom surface of the coupling member and the top surface of the cap plate; And
It is formed to be continuous and bent downward in one end of the first horizontal portion and is engaged with the first locking jaw of the cap plate which is continuous to the through hole and formed to be stepped upward, and is disposed in close contact between the through hole and the insertion portion. Cap assembly for a secondary battery comprising a first bent portion to be. The method of claim 9,
The upper insulator is,
A secondary battery cap assembly further comprising a second bent portion which is continuous at the other end of the first horizontal portion and is bent upwardly and wraps close to the side of the coupling member. The method of claim 9,
The upper insulator is,
A secondary battery cap assembly further comprising a second horizontal portion which is continuous in the first bent portion and is bent in a horizontal direction and is disposed in close contact between the lower surface of the cap plate and the upper surface of the flange portion. The method of claim 9,
The insertion portion has at least one first groove formed on the outer circumferential surface,
The first bent portion is formed on one side of the cap assembly for a secondary battery comprising a projection engaging with the first groove. The method of claim 8,
The insertion portion further has a second groove of the "V" shape formed in the end surface,
After the insertion portion is inserted into the coupling hole end portion of the insert portion is a secondary battery cap assembly that is riveted to the second engaging jaw formed in the stepped upward and continuous to the coupling hole of the coupling member. The method of claim 8,
The flange portion and the coupling member is a secondary battery cap assembly having a polygonal shape.

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