KR100635731B1 - Secondary battery - Google Patents

Abstract

Provided is a secondary battery which is prevented in the rotation of an electrode terminal by allowing the short side of an electrode terminal to have a long axis or a corner and is suppressed in the explosion due to electric short. The secondary battery comprises a case(210) where an electrode assembly(212) is accommodated and has first and second electrode taps drawn to the internal upper side; a cap plate(240) which covers the upper part of the case; an insulating plate(250) which is combined with the lower side of the cap plate; a terminal plate(260) which is combined with the bottom side of the insulating plate; a rotation-preventing electrode terminal(230) which penetrates the cap plate, the insulating plate and the terminal plate so as to be connected with the terminal plate; and a gasket which insulates the electrode terminal and the cap plate.

Description

Secondary Battery {SECONDARY BATTERY}

1 is an exploded perspective view showing a first embodiment of a rechargeable battery according to the present invention;

2 is an exploded perspective view showing a second embodiment of a rechargeable battery according to the present invention;

3 is a rear view showing a third embodiment of a secondary battery according to the present invention;

Figure 4 is a rear view showing a fourth embodiment of a secondary battery according to the present invention.

<Brief Description of Major Codes in Drawings>

210: case 210a: opening

212: electrode assembly 230: electrode terminal

231: terminal portion 233: insertion portion

240: cap plate 241: first terminal through

250: insulating plate 251: second terminal through

260: terminal plate 261: third terminal through

270: Insulated Case

The present invention relates to a secondary battery, and more particularly to a secondary battery provided with an electrode terminal.

Recently, compact and lightweight electric / electronic devices such as cellular phones, notebook computers, camcorders, etc. have been actively developed and produced. These portable electric / electronic devices have a battery pack that can be operated in a place where no separate power source is provided. The built-in battery pack includes at least one battery therein for outputting a predetermined level of voltage for driving the portable electric / electronic device for a period of time.

In consideration of economic aspects, the battery pack has recently adopted a secondary battery capable of charging and discharging. Typical secondary batteries include nickel-cadmium (Ni-Cd) batteries, nickel-hydrogen (Ni-MH) batteries, and lithium secondary batteries such as lithium (Li) batteries and lithium ion (Li-ion) batteries.

In particular, the lithium secondary battery has an operating voltage of 3.6 V, which is three times higher than that of a nickel-cadmium battery or a nickel-hydrogen battery, which is widely used as a power source for portable electronic equipment, and is rapidly increasing in terms of high energy density per unit weight. to be.

Such lithium secondary batteries mainly use lithium-based oxides as positive electrode active materials and carbon materials as negative electrode active materials. In general, a battery is classified into a liquid electrolyte battery and a polymer electrolyte battery according to the type of electrolyte. A battery using a liquid electrolyte is called a lithium ion battery, and a battery using a polymer electrolyte is called a lithium polymer battery. Moreover, although a lithium secondary battery is manufactured in various shapes, typical shapes include cylindrical shape, square shape, and pouch type.

In general, a secondary battery includes a first and second electrode plates coated with an active material, and a separator positioned between the first and second electrode plates to prevent shorting and to allow only movement of lithium ions (Li-ion). And a wound electrode assembly, a case accommodating the electrode assembly, an electrolyte injected into the case to allow movement of lithium ions, a cap assembly for sealing the case, and the like.

The secondary battery stacks first and second electrode plates and separators from which the first and second electrode tabs are drawn from the first and second electrode plates, and then winds them up to manufacture an electrode assembly.

Here, the first electrode tab of the electrode assembly is connected to the cap plate of the cap assembly to be described later, the second electrode tab is connected to the electrode terminal inserted into the cap assembly has a different polarity.

The cap assembly is assembled to the case, the cap plate for sealing the case, the insulation plate and the terminal plate are sequentially stacked. The electrode plate penetrating the cap plate, the insulation plate, and the terminal plate which are sequentially stacked are provided.

However, the installation of the electrode terminal in the conventional secondary battery is inserted by applying a constant force while rotating the electrode terminal. The cap plate, the insulation plate and the terminal plate are rotated in the process of coupling the electrode terminal, there is a problem that the coupling direction of each other is changed.

In addition, the secondary battery has a problem in that when the cap assembly is pressed in order to proceed with the assembly process of coupling the cap assembly closing the case to the case, the insulating plate is deformed and rotated so that the cap plate and the terminal plate may contact and short-circuit. have.

That is, since the cap plate is connected to the first electrode tab and the electrode terminal is connected to the second electrode tab to the terminal plate, the insulating plate has a function of insulating between the cap plate and the terminal plate having different polarities. However, when the insulation plate is bent and rotated by pressing, the insulation may be shorted between the cap plate and the terminal plate.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object of the present invention is to provide a secondary battery which prevents the cap assembly from rotating during the assembling process or use of the secondary battery.

The present invention for achieving the above object is coupled to the case, the cap plate for covering the upper portion of the case, the cap plate to cover the upper portion of the upper and second electrode tabs are drawn upwards therein The insulation plate, the terminal plate coupled to the bottom surface of the insulation plate, the cap plate, the insulation plate, and the terminal plate to be connected to the terminal plate, wherein the anti-rotation type electrode terminal and the electrode terminal and the Provided is a secondary battery including a gasket to insulate a cap plate.

The electrode terminal may be formed in a cross-section of the vortex, or the electrode terminal may be formed in a polygonal cross section.

Preferably, the cap plate, the insulation plate, and the terminal plate are formed with the same through-holes as the end faces of the electrode terminals.

Preferably, the gasket is formed in a tubular shape having the same shape as the cross section of the electrode terminal.

The lower end of the electrode terminal may be formed in a vortex shape, or the lower end of the electrode terminal may be formed in a polygon.

The electrode terminal may be a cathode.

The case is preferably formed in a square.

Hereinafter, with reference to the drawings will be described in detail an embodiment according to the present invention.

1 is an exploded perspective view showing a first embodiment of a secondary battery according to the present invention, Figure 2 is an exploded perspective view showing a second embodiment of a secondary battery according to the present invention.

3 is a rear view showing a third embodiment of a secondary battery according to the present invention, and FIG. 4 is a rear view showing a fourth embodiment of a secondary battery according to the present invention.

As shown in these drawings, the secondary battery is coupled to a case 210 having one side opened, an electrode assembly 250 accommodated in the case 210, and an opening 210a of the case 210. It consists of a cap assembly 220 closing 210.

The case 210 is formed in a substantially rectangular box shape and includes an opening 210a having one side opened, and formed of a metal material, so that the case 210 itself may serve as a terminal. As the material forming the case 210, an iron or stainless steel is also used, but an aluminum or aluminum alloy having excellent corrosion resistance so as to easily cope with corrosion while being a lightweight conductive metal is preferable. However, the material is not limited to this embodiment.

The electrode assembly 212 includes a first electrode plate 213 to which the first electrode tab 216 is attached, a second electrode plate 215 to which the second electrode tab 217 is attached, and a first electrode plate 213. ) And the separator 214 interposed between the second electrode plate 215 and the second electrode plate 215 are wound in a wound jelly-roll shape. The first and second electrode tabs 216 and 217 are led out of the electrode assembly 212.

In this case, after the electrode assembly 212 is accommodated on the upper side of the case 20, the insulation penetrating the first and second electrode tabs 216 and 217 to electrically insulate the electrode assembly 212 and the cap assembly 220 from the upper surface thereof. The case 270 is installed.

The cap assembly 220 includes a cap plate 240, an insulation plate 250, a terminal plate 260, and an electrode terminal 230.

The cap plate 240 is formed of a metal plate having a size and a shape corresponding to the opening 210a of the case 210, and a first terminal through-hole 241 into which the electrode terminal 230 is inserted is formed at the center thereof. The inner surface of the first terminal through hole 241 is provided with a tubular gasket 246 to insulate the electrode terminal 230 and the cap plate 240. In addition, an electrolyte injection hole 242 for injecting an electrolyte is formed at one side of the central portion of the cap plate 240, and the electrolyte injection hole 242 is sealed by a stopper 243.

At this time, the stopper 115 for blocking the electrolyte injection hole 113 is formed in a pin shape.

An insulating plate 250 is installed on the lower surface of the cap plate 240. The insulating plate 250 is formed of an insulating material such as the gasket 246, and the second terminal through hole 251 is formed to communicate with the first terminal through hole 241 of the cap plate 240.

A terminal plate 260 having a third terminal through hole 261 communicating with the second terminal through hole 251 is coupled to the bottom surface of the insulating plate 250.

The terminal plate 260 may be formed of Ni metal or an alloy thereof.

Here, the electrode terminal 230 may have a cross section whose shape is a vortex or a polygon. In other words, the electrode terminal 230 is pressed by the rotating spinner to penetrate the first, second, and third terminal through holes 241, 251, and 261. At this time, when the electrode terminal 230 is formed in a circular cross section, the cap plate 240 or the insulating plate 250 through which the electrode terminal 230 penetrates and the terminal plate 260 are rotated when the electrode terminal 230 is inserted by the spinner. Can be. However, when the electrode terminal 230 is formed to have a polygonal shape as shown in FIG. 1, as shown in FIG. 1, or as shown in FIG. 2, the electrode terminal 230 may not rotate even if it is in contact with the spinner. That is, the electrode terminal 230 is divided into a long axis and a short axis when the cross section is a vortex or an elliptical shape, and thus cannot be easily rotated. In addition, since the electrode terminal 230a forms a corner when its cross section is polygonal, it is also not rotatable.

In this case, the first, second, and third terminal through holes 241, 251, and 261 may be formed to correspond to the cross section of the electrode terminal 230.

In addition, the electrode terminal 230 may be described by dividing the terminal unit 231 and the insertion unit 233. The terminal portion 231 is formed such that its cross section has an area larger than that of the inserting portion 233 and is connected to a protection circuit module (not shown). The insertion part 233 is connected to the terminal plate 260 through the first, second, and third terminal through holes 241, 251, and 261. Thus, although the terminal portion 231 of the electrode terminal 230 has a circular cross section, the cross section of the insertion portion 233 inserted into the first, second, and third terminal through holes 241, 251, 261 is formed in a vortex or a polygon. . Of course, the first, second, and third terminal through holes 241, 251, and 261 are formed to correspond to the cross section of the electrode terminal 230. Here, the polygon may be a rectangle formed with a longer length on one side.

The gasket 246 is inserted into the outer surface of the electrode terminal 230. The gasket 246 is tubular, and an inner surface thereof is formed to correspond to the outer surface shape of the electrode terminal 230, and an outer surface thereof is formed to correspond to the shape of the first terminal through hole 241 of the cap plate 240. Therefore, as shown in FIG. 3, if the shape of the insertion part 233 is a vortex, it is formed as a vortex tube, and as shown in FIG. 4, if the shape of the insertion part 233 ′ is a polygon, it is formed as a polygonal tube. .

The cap assembly 220 has the electrode plate 230 when the cap plate 240, the insulating plate 250, and the terminal plate 260 are sequentially stacked so that the first, second, and third terminal through holes 241, 251, and 261 are disposed in communication. Is pressed by a rotating spinner to penetrate through the first, second, and third terminal through holes 241, 251 and 261.

Accordingly, the electrode terminal 230 may press the cap plate 240 while the electrode terminal 230 rotates, or press the cap assembly 220 to couple the cap assembly 220 to the case 210. Since the cross-section of the 230 is formed in a vortex or a polygon, the cap plate 240 and the insulating plate 250 are coupled, thereby preventing the insulating plate 250 from rotating.

According to the present invention, the secondary battery is formed such that the cross section of the electrode terminal has a long axis or an edge even when the electrode terminal is pressed with a spinner to insert the electrode terminal into the cap plate, the insulating plate, and the terminal plate. There is an advantage that the rotation is prevented.

In addition, the secondary battery has an advantage of preventing a safety accident such as an explosion due to a short circuit.

Claims (9)

A case accommodating an electrode assembly in which the first and second electrode tabs are drawn upward; A cap plate covering an upper portion of the case; An insulation plate coupled to a bottom surface of the cap plate; A terminal plate coupled to a bottom surface of the insulating plate; An anti-rotation type electrode terminal connected to the terminal plate through the cap plate, the insulating plate, and the terminal plate; And And a gasket for insulating the electrode terminal and the cap plate. The method of claim 1, The electrode terminal is a secondary battery, characterized in that the cross section is formed in a vortex. The method of claim 1, The electrode terminal is a secondary battery, characterized in that the cross section is formed in a polygon. The method of claim 1, The cap plate, the insulating plate, and the terminal plate, the secondary battery, characterized in that the same through-holes are formed in the cross section of the electrode terminal. The method of claim 1, The gasket is a secondary battery, characterized in that the tubular shape of the same shape as the cross section of the electrode terminal. The method of claim 1, The electrode terminal is a secondary battery, characterized in that the cross section of the lower side is formed in a vortex. The method of claim 1, The electrode terminal is a secondary battery, characterized in that the cross section of the lower side is formed in a polygon. The method of claim 1, The electrode terminal is a secondary battery, characterized in that the negative electrode. The method of claim 8, The case is a secondary battery, characterized in that formed in a square.

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