KR100614355B1 - Lithium-ion Secondary Battery - Google Patents

Abstract

The present invention relates to a lithium ion secondary battery, and more particularly, to a lithium ion secondary battery in which a seating groove in which an insulating plate and a terminal plate are seated is formed on a lower surface of a cap plate to prevent the terminal plate from rotating when the cap assembly is assembled. .

The lithium ion secondary battery of the present invention comprises an electrode assembly including a positive electrode plate, a negative electrode plate, and a separator, a can containing the electrode assembly and the electrolyte, a cap plate, an insulating plate, a terminal plate, and an electrode terminal. A lithium ion secondary battery comprising a cap assembly coupled to an upper opening to seal a can, wherein the cap plate has a first seating groove formed at a size corresponding to the insulating plate on a lower surface thereof and seating the insulating plate. It is characterized by being formed.

Lithium-ion secondary battery, cap plate, seating groove, anti-rotation

Description

Lithium Ion Secondary Battery

1 is an exploded perspective view showing a conventional lithium ion secondary battery.

Figure 2 is an exploded perspective view showing a lithium ion secondary battery according to the present invention.

Figure 3a is a bottom view of the cap plate according to an embodiment of the present invention.

3B is a cross-sectional view taken along the line A-A of FIG. 3A.

Figure 4a is a bottom view of the insulating plate according to an embodiment of the present invention.

4B is a cross-sectional view taken along line B-B in FIG. 4A.

5 is a cross-sectional view of an insulating plate according to another embodiment of the present invention.

6 is a cross-sectional view of a terminal plate according to another embodiment of the present invention.

7 is a cross-sectional view of an insulating plate according to another embodiment of the present invention.

8A is a bottom view of the cap assembly in which the cap plate of FIG. 3A and the insulating plate of FIG. 4A are combined.

8B is a cross-sectional view taken along the line C-C in FIG. 9A.

9 is a cross-sectional view of the cap assembly of the cap plate of Figure 3a and the insulating plate of Figure 6 and the terminal plate of Figure 6 combined.

FIG. 10 is a cross-sectional view of the cap assembly of the cap plate of FIG. 3A and the insulation plate of FIG. 7 and the terminal plate of FIG.

<Description of Symbols for Major Parts of Drawings>

210-Can 220, 220a, 220b-Cap assembly

230-Electrode terminal 240-Cap plate

244-First Seating Home

250, 250a, 250b-Insulated Plate 252-Second Seating Groove

252a-1st fixed groove 252b-2nd fixed groove

260, 260a-Terminal plate 262-Anti-rotation protrusion

The present invention relates to a lithium ion secondary battery, and more particularly, to a lithium ion secondary battery in which a seating groove in which an insulating plate and a terminal plate are seated is formed on a lower surface of a cap plate to prevent the terminal plate from rotating when the cap assembly is assembled. .

In general, as the light weight and high functionalization of portable wireless devices such as a video camera, a portable telephone, a portable computer, and the like progress, many studies have been conducted on secondary batteries used as driving power. Such secondary batteries include, for example, nickel cadmium batteries, nickel hydrogen batteries, nickel zinc batteries, and lithium secondary batteries. Among them, lithium secondary batteries are rechargeable, compact, and large-capacity, and are widely used in advanced electronic devices because of their high operating voltage and high energy density per unit weight.

1 is an exploded perspective view of a conventional lithium ion secondary battery.

The lithium ion secondary battery accommodates the electrode assembly 112 including the positive electrode plate 113, the negative electrode plate 115, and the separator 114 together with the electrolyte in the can 110, and the upper opening 110a of the can 110. ) Is formed by sealing the cap assembly 120.

The cap assembly 120 includes a cap plate 140, an insulation plate 150, a terminal plate 160, and an electrode terminal 130. The cap assembly 120 is coupled to a separate insulating case 170 to be coupled to the upper opening 110a of the can to seal the can 110.

 The cap plate 140 is formed of a metal plate having a size and shape corresponding to that of the upper opening 110a of the can 110. The terminal hole 1 141 of a predetermined size is formed in the center of the cap plate 140, the electrode terminal 130 is inserted into the terminal hole 1 (141). When the electrode terminal 130 is inserted into the terminal through-hole 1 (141), a tubular gasket tube 146 is coupled to the outer surface of the electrode terminal 130 for insulation between the electrode terminal 130 and the cap plate 140. Are inserted together. Meanwhile, an electrolyte injection hole 142 is formed at one side of the cap plate 140 at a predetermined size. After the cap assembly 120 is assembled to the upper opening 110a of the can 110, electrolyte is injected through the electrolyte injection hole 142, and the electrolyte injection hole 142 is sealed by a stopper 143.

The electrode terminal 130 is connected to the negative electrode tab 117 of the negative electrode plate 115 or the positive electrode tab 116 of the positive electrode plate 113 to act as a negative electrode terminal or a positive electrode terminal.

The insulating plate 150 is formed of an insulating material such as a gasket and is coupled to the bottom surface of the cap plate 140. The insulating plate 150 has a terminal through-hole 2 151 into which the electrode terminal 130 is inserted at a position corresponding to the terminal through-hole 1 141 of the cap plate 140. A mounting groove 152 corresponding to the size of the terminal plate 160 is formed on the bottom surface of the insulating plate 150 so that the terminal plate 160 is seated.

The terminal plate 160 is formed of Ni alloy, and is coupled to the bottom surface of the insulating plate 150. The terminal plate 160 is provided with a terminal through hole 3 161 into which the electrode terminal 130 is inserted at a position corresponding to the terminal through hole 1 141 of the cap plate 140, and the electrode terminal 130. Is insulated by the gasket tube 146 and coupled through the terminal through hole 1 141 of the cap plate 140, so that the terminal plate 160 is electrically insulated from the cap plate 140 while the electrode terminal 130 is insulated from the gasket tube 146. Is electrically connected).

On the other hand, the method of coupling the electrode terminal 130 to the cap plate 140, the insulating plate 150 and the terminal plate 160 by applying a constant force while rotating the electrode terminal 130 of the cap plate 140 It is inserted into the terminal through-hole 1 (141). When the electrode terminal 130 passes through the terminal through hole 1 141, the terminal through hole 2 151 and the terminal formed on the insulation plate 150 and the terminal plate 160 are coupled to the lower surface of the cap plate 140 again. It passes through the through hole 3 (161). Therefore, the insulation plate 150 and the terminal plate 160 is rotated around the terminal through-hole 1 (141) of the cap plate 140 in the process of inserting the electrode terminal 130 has a problem that the coupling direction of each other is changed do.

In addition, in the process of welding the positive electrode tab 116 to the lower surface of the terminal plate 160, the terminal plate 160 is rotated to cause a problem that the direction is displaced.

Accordingly, in order to couple the assembled cap assembly 120 to the insulating case 170, the insulating plate 150 and the terminal plate 160 are forcibly rotated about the electrode terminal 130 again to reverse the cap plate 140. Since the additional work to be arranged in the same direction as the has a problem that the process time is long.

In addition, the terminal plate 160 is formed of a thin metal plate, there is a problem that some deformation occurs in the reverse rotation process.

In order to solve the above problems, the present invention provides a lithium ion secondary battery in which a seating groove in which an insulating plate and a terminal plate are seated is formed on a lower surface of the cap plate, thereby preventing the terminal plate from rotating when the cap assembly is assembled. There is a purpose.

In order to solve the above problems, the lithium ion secondary battery of the present invention includes an electrode assembly including a positive electrode plate, a negative electrode plate, and a separator, a can containing the electrode assembly and an electrolyte, a cap plate, an insulating plate, a terminal plate, In the lithium ion secondary battery comprising an electrode terminal and coupled to the upper opening of the can and including a cap assembly for sealing the can, the cap plate is formed on the lower surface corresponding to the size of the insulating plate and the insulating plate It is characterized in that it is formed including a first seating groove is seated.

In addition, in the present invention, the insulating plate may be formed to have a size corresponding to the terminal plate on the lower surface, including a second mounting groove on which the terminal plate is seated.

In addition, in the present invention, the insulating plate is formed with a first fixing groove is formed at a predetermined position of the second seating groove, the terminal plate is formed on the upper surface is formed to include a rotation preventing projection coupled to the first fixing groove. Can be.

In addition, in the present invention, the insulating plate has a second fixing groove is formed at a predetermined position, the terminal plate may be formed including an anti-rotation protrusion is formed on the upper surface coupled to the second fixing groove.

In addition, in the present invention, the first seating groove is preferably formed to a depth of 0.1mm to 0.5mm, the first seating groove may be formed by pressing the lower surface of the cap plate.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

2 is an exploded perspective view showing a lithium ion secondary battery according to the present invention. 3A shows a bottom view of a cap plate according to an embodiment of the present invention. 3B is a cross-sectional view taken along the line A-A of FIG. 3A. 4A shows a bottom view of an insulating plate according to an embodiment of the present invention. 4B is a cross-sectional view taken along line B-B in FIG. 4A. 5 is a sectional view of an insulating plate according to another embodiment of the present invention. 6 is a cross-sectional view of a terminal plate according to another embodiment of the present invention. 7 is a sectional view of an insulating plate according to another embodiment of the present invention. 8A illustrates a bottom view of a cap assembly in which the cap plate of FIG. 3A and the insulating plate of FIG. 4A are combined. FIG. 8B is a sectional view taken along the line C-C in FIG. 9A. 9 is a cross-sectional view of a cap assembly in which the cap plate of FIG. 3A and the insulation plate of FIG. 6 and the terminal plate of FIG. 6 are combined. FIG. 10 is a cross-sectional view of the cap assembly in which the cap plate of FIG. 3A and the insulation plate of FIG. 7 and the terminal plate of FIG. 6 are combined.

In the lithium ion secondary battery according to the present invention, referring to FIG. 2, a can 210, an electrode assembly 212 accommodated in the can 210, and an upper opening 210a of the can 210 may be formed. It is formed including a cap assembly 220 for sealing.

The can 210 may be formed of a metal material having a substantially box shape, and is preferably formed of lightweight aluminum or an aluminum alloy. The can 210 includes an upper opening 210a having one surface thereof opened, and the electrode assembly 212 is accommodated through the upper opening 210a.

The electrode assembly 212 includes a positive electrode plate 213, a negative electrode plate 215, and a separator 214. The positive electrode plate 213 and the negative electrode plate 215 may be stacked through a separator 214 and then wound in a jelly-roll form. The positive electrode tab 216 is welded to the positive electrode plate 213, and an end portion of the positive electrode tab 216 protrudes above the electrode assembly 212. The negative electrode tab 217 is also welded to the negative electrode plate 215, and an end portion of the negative electrode tab 217 also protrudes above the electrode assembly 212.

The cap assembly 220 includes a cap plate 240, an insulating plate 250, a terminal plate 260, and an electrode terminal 230. The cap assembly 220 is coupled to a separate insulating case 270 is coupled to the upper opening 210a of the can 210 to seal the can 210.

 Referring to FIGS. 3A and 3B, the cap plate 240 is formed of a metal plate having a size and a shape corresponding to the upper opening 210a of the can 210. A terminal through hole 4 241 having a predetermined size is formed in the center of the cap plate 240, and the electrode terminal 230 is inserted into and coupled to the terminal through hole 4 241. A tubular gasket tube 246 is assembled on the inner surface of the terminal hole 4 241 to insulate the electrode terminal 230 and the cap plate 240.

The lower surface of the cap plate 240 includes the terminal through hole 4 241 and has a first seating groove 244 having a size corresponding to that of the insulating plate 250. In more detail, the first seating groove 244 is formed to have a size corresponding to the insulating plate 250 on the bottom surface of the cap plate, including the area where the terminal through hole 4 241 is formed, and the insulating plate ( 250) is seated. The first seating groove 244 may be formed by pressing the lower surface of the cap plate 240 to the upper surface.

The depth of the first seating groove 244 is formed to an appropriate depth in consideration of the size of the contact surface of the cap plate 240 and the insulating plate 250, preferably the depth of the first seating groove 244 is 0.1mm To 0.5 mm. If the depth of the first mounting groove 244 is too small, the force for fixing the insulating plate 250 is weak. However, if the depth of the first seating groove 244 is too deep, the strength of the cap plate 240 is weak.

The electrolyte injection hole 242 is formed in a predetermined size on the other side of the cap plate 240. After the cap assembly 220 is assembled to the upper opening 210a of the can 210, electrolyte is injected through the electrolyte injection hole 242, and the electrolyte injection hole 242 is separated by a separate sealing means 243. Is sealed

4A and 4B, the insulating plate 250 is formed of an insulating material such as a gasket, and is coupled to the bottom surface of the cap plate 240. The insulating plate 250 includes a terminal through hole 5 251 and a second seating groove 252.

The terminal through hole 5 251 is formed at a position corresponding to the terminal through hole 4 241 of the cap plate 240 when the insulating plate 250 and the cap plate 240 are coupled to each other, and the electrode terminal ( 230) is inserted.

The second seating groove 252 is formed on the bottom surface of the insulating plate 250 to have a size corresponding to the terminal plate 260. The second seating groove 252 is preferably formed to a depth lower than the thickness of the terminal plate 260.

The terminal plate 260 is formed of a Ni alloy in a plate shape and is fixed to the second seating groove 252 formed on the bottom surface of the insulating plate 250. Therefore, the terminal plate 260 is coupled to the insulating plate 250 to move together. The terminal plate 260 is provided with a terminal through hole 6 261 in which the electrode terminal 230 is inserted at a position corresponding to the terminal through hole 4 241 of the cap plate 240, and the insulating plate 250. Insulated from the cap plate 240 is electrically connected to the electrode terminal 230 by.

The electrode terminal 230 is inserted into the terminal through holes 241, 251, and 261 formed in the cap plate 240, the insulating plate 250, and the terminal plate 260, respectively, and the electrode assembly through the terminal plate 260. Is electrically connected to the negative electrode tab 217 of 212. The electrode terminal 230 is electrically insulated from the cap plate 240 by the gasket tube 246 when the electrode terminal 230 is inserted into the terminal through hole 4 241 of the cap plate 240. Meanwhile, the positive electrode tab 216 may be connected to the electrode terminal 230 by a method of forming the electrode assembly 212.

5 is a cross-sectional view of a cross-sectional view of an insulating plate according to another embodiment of the present invention. 6 is a cross-sectional view of a terminal plate according to another embodiment of the present invention.

Referring to FIG. 5, the insulating plate 250a includes a first fixing groove 252a having a predetermined size formed at a predetermined position of the second seating groove 252. The first fixing groove 252a is preferably formed on the opposite side of the terminal through hole 5 (251). The first fixing groove 252a may be formed in various shapes such as a square shape and a circular shape, and is preferably formed in a quadrangular shape.

6, the anti-rotation protrusion 262 protrudes from the upper surface of the terminal plate 260a. The anti-rotation protrusion 262 is formed to have a size corresponding to the first fixing groove 252a formed on the bottom surface of the insulating plate 250a, and is coupled to the first fixing groove 252a to connect the terminal plate 260a. ) Is not rotated relative to the insulating plate 250a.

Accordingly, the insulating plate 250 and the terminal plate 260 are not rotated with respect to the cap plate 240 by the first fixing groove 252a and the anti-rotation protrusion 262.

7 is a sectional view of an insulating plate according to another embodiment of the present invention.

Referring to FIG. 7, the insulating plate 250b is formed to include a second fixing groove 252b at a predetermined position on a lower surface of the plate without a separate mounting groove. The anti-rotation protrusion 262 formed on the upper surface of the terminal plate 260a in FIG. 6 is coupled to the second fixing groove 252b. Accordingly, the terminal plate 260a is fixed to the insulating plate 250b that is coupled to and fixed to the first seating groove 244 of the cap plate 240 to prevent rotation about the cap plate 240.

Next will be described the action of the cap assembly included in the lithium ion secondary battery according to the present invention.

FIG. 8A illustrates a bottom view of a cap assembly in which a terminal plate is coupled to the cap plate of FIG. 3A and the insulating plate of FIG. 4A. FIG. 8B is a sectional view taken along the line C-C in FIG. 8A.

8A and 8B, in the cap assembly 220, the cap plate 240, the insulation plate 250, and the terminal plate 260 coincide with the centers of the respective terminal holes 241, 251, and 261. And the electrode terminals 230 are coupled to and fixed to the respective terminal through holes 241, 251, and 261. The insulating plate 250 is seated in the first seating groove 244 formed on the bottom surface of the cap plate 240. The terminal plate 260 is seated in the second seating groove 252 formed on the bottom surface of the insulating plate 250.

The electrode terminal 230 is inserted and coupled to the terminal through-hole 4 241 of the cap plate 240 is stacked as shown in Figure 8a while being rotated by a constant force. When the electrode terminal 230 passes through the terminal through hole 4 241, the terminal through hole 5 251 and the terminal of the insulating plate 250 and the terminal plate 260 are coupled to the lower surface of the cap plate 240 again. Passes through through 6 (261). At this time, since the inner diameters of the terminal through holes 5 251 and the terminal through holes 661 formed in the insulating plate 250 and the terminal plate 260 are formed to be the same as or slightly larger than the outer diameter of the electrode terminal 230, the electrode terminal is formed. In the process of inserting 230, a friction force is generated between the insulating plate 250 and each terminal through hole 251 and 261 of the terminal plate 260 and the electrode terminal 230. Therefore, the insulating plate 250 and the terminal plate 260 are coupled to the first seating groove 244 of the cap plate 240, and the terminal plate 260 is the second seating groove 252 of the insulating plate 250. Since the insulation plate 250 and the terminal plate 260 is not rotated.

In addition, the cap assembly 220 has a reduced overall height when the cap plate, the insulating plate and the terminal plate are assembled. Therefore, when the cap assembly is assembled to the can, the internal volume of the can is increased, and the capacity of the secondary battery can be increased.

FIG. 9 is a cross-sectional view of the cap assembly in which the cap plate of FIG. 3A and the insulation plate of FIG. 5 and the terminal plate of FIG. 6 are combined.

Referring to FIG. 9, the cap assembly 220a is stacked with the cap plate 240, the insulation plate 250a, and the terminal plate 260a coincident with the centers of the respective terminal holes 241, 251, and 261. The electrode terminal 230 is coupled to the terminal through holes 241, 251, 261 is fixed. In this case, the insulating plate 250a is seated in the first seating groove 244 formed on the bottom surface of the cap plate 240. The terminal plate 260a is mounted on the second seating groove 252 formed on the bottom surface of the insulating plate 250a. In addition, a first fixing groove 252a is further formed in the second seating groove 252 of the insulating plate 250b, and the first fixing groove 252a is prevented from rotating on the upper surface of the terminal plate 260a. The protrusion 262 is coupled. Therefore, the insulating plate 250a and the terminal plate 260a are fixed without being rotated with respect to the cap plate 240 in the process of coupling the electrode terminal 230.

FIG. 10 is a cross-sectional view of the cap assembly in which the cap plate of FIG. 3A and the insulation plate of FIG. 7 and the terminal plate of FIG. 6 are combined.

Referring to FIG. 10, the cap assembly 220b is stacked with the cap plate 240, the insulation plate 250b, and the terminal plate 260a coincident with the centers of the respective terminal holes 241, 251, and 261. The electrode terminal 230 is coupled to the terminal through holes 241, 251, 261 is fixed. The insulating plate 250b is seated in the first seating groove 244 formed on the bottom surface of the cap plate 240. The terminal plate 260a is mounted on the bottom surface of the insulating plate 250b. At this time, the anti-rotation protrusion 262 formed on the upper surface of the terminal plate 260a is coupled to the second fixing groove 252b formed on the lower surface of the insulating plate 250b. Therefore, the insulating plate 250b and the terminal plate 260a are fixed without being rotated with respect to the cap plate 240 in the process of coupling the electrode terminal 230.

As described above, the present invention is not limited to the specific preferred embodiments described above, and any person having ordinary skill in the art to which the present invention belongs without departing from the gist of the present invention as claimed in the claims. Various modifications are possible, of course, such changes are within the scope of the claims.

According to the lithium ion secondary battery according to the present invention, in forming the cap assembly by inserting the electrode terminals in the cap plate, the insulating plate and the terminal plate, it is possible to prevent the terminal plate from rotating relative to the cap plate when the electrode terminal is inserted. And, there is an effect that can be assembled more easily the cap assembly.

In addition, according to the present invention, since the insulation plate and the terminal plate are not rotated when the electrode terminal is inserted, the reverse rotation is not performed again, thereby preventing deformation of the terminal plate.

In addition, the cap assembly has a reduced overall height when the cap plate, the insulating plate, and the terminal plate are assembled to increase the internal volume of the can when the cap assembly is assembled to the can, thereby increasing the capacity of the secondary battery. It works.

Claims (6)

An electrode assembly including a positive electrode plate, a negative electrode plate, and a separator, a can containing the electrode assembly and an electrolyte, a cap plate, an insulating plate, a terminal plate, and an electrode terminal, are coupled to an upper opening of the can to seal the can. In the lithium ion secondary battery comprising a cap assembly, The cap plate is a lithium ion secondary battery, characterized in that formed on the lower surface corresponding to the size of the insulating plate including a first seating groove in which the insulating plate is seated. The method of claim 1, The insulating plate is formed on a lower surface corresponding to the size of the terminal plate, the lithium ion secondary battery characterized in that it comprises a second seating groove on which the terminal plate is seated. The method of claim 2, The insulating plate has a first fixing groove is formed at a predetermined position of the second seating groove, The terminal plate is formed on the upper surface is a lithium ion secondary battery, characterized in that it comprises a rotation preventing projection coupled to the first fixing groove. The method according to any one of claims 1 to 3, The first seating groove is a lithium ion secondary battery, characterized in that formed to a depth of 0.1mm to 0.5mm. The method of claim 4, wherein The first seating groove is a lithium ion secondary battery, characterized in that formed by pressing the lower surface of the cap plate. The method of claim 1, The insulating plate is formed with a second fixing groove at a predetermined position, The terminal plate is formed on the upper surface is a lithium ion secondary battery, characterized in that it comprises a rotation preventing projection coupled to the second fixing groove.

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