KR100995474B1 - Apparatus for Welding Connecting Lead of Lithium Secondary Battery - Google Patents

Abstract

The present invention relates to a welding device for connecting lead of a lithium secondary battery, and more particularly, to a lithium secondary battery capable of quickly removing foreign substances generated during welding of a connecting lead and an electrode tab, thereby preventing a poor welding of the connecting lead and an electrode tab. It relates to a connection lead welding device.

The connecting lead welding apparatus of the lithium secondary battery of the present invention is a jig in which a pouch pack accommodated in a pouch packaging material and a protective circuit module welded to the electrode tab by a connecting lead are mounted such that the electrode tab of the electrode assembly protrudes to the outside. And a welding part including symmetrically formed upper and lower portions of the jig, and having a shang conveying means for transferring a welding rod mounted at each end to a welding position of the electrode tab and the connecting lead, and a welding position of the electrode tab and the connecting lead. It is installed spaced apart from a predetermined distance, characterized in that it comprises a foreign material removal unit for sucking and removing foreign substances generated during welding and a control unit for controlling the operation of the welding unit and the foreign material removal unit.

Lithium secondary battery, resistance welding, foreign material removal

Description

Apparatus for Welding Connecting Lead of Lithium Secondary Battery

Figure 1a is a perspective view showing a state before the pouch packaging material is sealed in a general pouch type lithium secondary battery.

1B is a plan view illustrating a welding position between an electrode tab coupled to an electrode assembly of a pouch type lithium secondary battery and a connection lead coupled to a protection circuit module.

Figure 2a is a schematic diagram of a connection lead welding apparatus of a lithium secondary battery according to an embodiment of the present invention.

2B is a side view of FIG. 2A;

Figure 3 is a perspective view of a jig used in the connection lead welding apparatus of a lithium secondary battery according to an embodiment of the present invention.

Figure 4 is a front view of the foreign material suction portion used in the connection lead welding apparatus according to an embodiment of the present invention.

5 is a front view of the foreign material collecting container used in the connection lead welding apparatus according to the present invention.

6 is a schematic view showing the action of the connection lead welding apparatus of a lithium secondary battery according to the present invention.

<Explanation of symbols for main parts of the drawings>                 

100-Pouch Type Secondary Battery 105-Pouch Pack

110-electrode assembly 114, 115-electrode tab

120-Pouch case 130-Protective circuit module

140, 145-Leads

200-jig 300-weld

310-welding rod 320-shanghai

400-Foreign body removal unit 410-Foreign body suction unit

430-Foreign Material Collector 440-Vacuum Pump

500-control unit

The present invention relates to a welding device for connecting lead of a lithium secondary battery, and more particularly, to a lithium secondary battery capable of quickly removing foreign substances generated during welding of a connecting lead and an electrode tab, thereby preventing a poor welding of the connecting lead and an electrode tab. It relates to a connection lead welding device.

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 widely used in the field of advanced electronic devices because of their advantages of small size and large capacity, high operating voltage and high energy density per unit weight. In general, a lithium secondary battery is classified into a liquid electrolyte battery and a polymer electrolyte battery according to the type of electrolyte, and 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. The lithium secondary battery mainly uses a lithium-based oxide as a cathode active material and a carbon material as a cathode active material.

Pouch-type lithium secondary battery of the lithium secondary battery is composed of a pouch exterior material composed of a metal foil layer and a multi-layered film of a synthetic resin layer coated on the upper and lower surfaces of the metal foil layer, and constitutes an external appearance, and uses a cylindrical can using a metal can. Or the weight of the battery can be significantly reduced than the rectangular lithium secondary battery has the advantage that the weight of the lithium secondary battery can be reduced.

The pouch-type lithium secondary battery has an electrode assembly in which a positive electrode plate and a negative electrode plate and a separator interposed between the positive electrode plate and the negative electrode plate in the form of jelly roll are accommodated in the pouch packaging material. Is protruded and connected to the protection circuit module.

The protecting circuit module (PCM) generally has a structure including various protection circuits and positive temperature elements on a printed circuit board (PCB).                         

1A is a perspective view illustrating a state before a pouch packaging material is sealed in a general pouch-type lithium secondary battery, and FIG. 1B is a plan view illustrating a welding position between an electrode tab coupled to an electrode assembly and a connection lead coupled to a protective circuit module. .

The pouch-type lithium secondary battery 100 includes an electrode assembly 110, a pouch case 120 containing the electrode assembly 110, and a protection circuit module for controlling charging and discharging of the electrode assembly 110 ( 130 and connection leads 140 and 145 coupled to the protection circuit module 130 and electrically connecting the electrode assembly 110 and the protection circuit module 130.

The electrode assembly 110 is coated with any one of a positive electrode active material and a negative electrode active material, for example, a first electrode plate 111 coated with a positive electrode active material, another one of a positive electrode active material and a negative electrode active material, for example, coated with a negative electrode active material. The second electrode plate 112, the first electrode plate 111, and the second electrode plate 112 positioned between the first electrode plate 111 and the second electrode plate 112. And a separator 113 for preventing the movement of lithium ions. In addition, the first electrode plate 111 is generally made of aluminum (Al) and is protruded to a predetermined length to the first electrode tab 114 serving as a positive electrode tab. The second electrode plate 112 is generally made of a nickel (Ni) material, and a second electrode tab 115 that protrudes a predetermined length upward and serves as a negative electrode tab is bonded to the second electrode plate 112. In addition, an insulating tape 116 may be further provided to prevent a short circuit between the first electrode tab 114 and the second electrode tab 115 and the pouch packaging material 120.

The pouch packaging material 120 includes a lower portion 121 formed with a space 121a in which the electrode assembly 110 is accommodated, and an upper portion 122 covering a lower portion 121 formed with the space 121a. The edge of the space 121a of the lower part 121 is a junction part 123 that is bonded to the upper part 122 after the electrode assembly 110 is accommodated in the pouch sheath 120 and seals the pouch sheath 120. . The space 121a for accommodating the electrode assembly 110 is formed through a press process or the like. Hereinafter, the pouch packaging material 120 in which the electrode assembly 110 is accommodated and sealed is referred to as a pouch pack 105.

The protection circuit module 130 controls the charging, discharging, and malfunction of the electrode assembly 110. For example, when the overcurrent flows from the electrode assembly 110, the protection circuit module 130 blocks the overcurrent. do. The protection circuit module 130 is electrically connected to the first electrode tab 114 and the second electrode tab 115 through the first connection lead 140 and the second connection lead 145. Accordingly, the first connection lead 140 and the second connection lead 145 are bonded to the first electrode tab 114 and the second electrode tab 115 of the electrode assembly 110 and the protective circuit module ( 132 and 135, respectively, to electrically connect them. The connection leads 140 and 145 and the electrode tabs 114 and 115 are welded to each other by spot welding at a welding position a in contact with each other.

However, in the spot welding process, foreign matter is generated, and when the foreign material is present between the electrode tab and the connecting lead to be welded, and between the electrode and the connecting lead or the electrode tab, the welding becomes incomplete and the coupling between the electrode tab and the connecting lead falls. Will occur.

 The present invention for solving the above problems provides a connection lead welding apparatus for a lithium secondary battery that can quickly remove foreign substances generated during welding of the connection lead and the electrode tab to prevent the occurrence of poor welding of the connection lead and the electrode tab. Its purpose is to.

In order to achieve the above object, the lithium secondary battery connection lead welding device of the present invention includes a pouch pack and an electrode tab connected to a pouch pack accommodated in a pouch case so that the electrode tab of the electrode assembly protrudes to the outside. A welding part including a jig in which a protective circuit module welded by the jig is mounted, symmetrically formed on upper and lower parts of the jig, and a conveying means for transferring a welding rod mounted at each end to a welding position of the electrode tab and a connection lead; And a foreign material removal unit installed at a predetermined distance away from the welding position of the electrode tab and the connection lead, and configured to suck and remove foreign substances generated during welding, and a control unit to control operations of the welding unit and the foreign material removing unit. It is done.

In the present invention, the jig has a first seating groove in which the pouch pack is seated and a second seating groove in which the protective circuit module is seated so that a predetermined portion of the electrode tab and the connection lead overlaps with each other. A through hole may be formed to penetrate at a position corresponding to the position so that the electrode moves up and down.

In addition, in the present invention, the foreign material removing unit is connected to the foreign matter suction unit and the foreign matter suction unit is installed close to the welding position and the foreign matter collecting container for collecting the sucked foreign matter and the vacuum pump connected to the foreign material collecting cylinder. It may be formed to include.                     

In addition, the foreign matter suction portion in the present invention is preferably formed to include an extension portion formed to extend in the horizontal direction at the end.

In addition, the foreign matter collecting container in the present invention includes an opening and closing door formed on one side, it may be formed to enable the removal of the collected foreign matter.

In addition, in the present invention, the connecting pipe is preferably formed of a flexible pipe.

In addition, in the present invention, the vacuum pump is preferably formed of a diaphragm pump.

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

Figure 2a shows a schematic block diagram of a connection lead welding apparatus of a lithium secondary battery according to an embodiment of the present invention. FIG. 2B shows a side view of FIG. 2A. Figure 3 shows a perspective view of a jig used in the connection lead welding apparatus of a lithium secondary battery according to an embodiment of the present invention. Figure 4 shows a front view of the foreign material suction portion used in the connection lead welding apparatus according to an embodiment of the present invention. 5 is a front view of a foreign material collecting container used in the connection lead welding apparatus according to the present invention. 6 is a schematic view showing the action of the connection lead welding apparatus of a lithium secondary battery according to the present invention.

2A and 2B, the connection lead welding apparatus for a lithium secondary battery according to the present invention includes a jig 200, a welding part 300, a foreign material removing part 400, and a control part 500.

3, the jig 200 includes a first seating groove 210 in which the pouch pack 105 is seated and a second seating recess 220 in which the protection circuit module 130 is seated. Are connected to each other. Accordingly, the jig 200 is a pouch pack 105 and a protection circuit such that the electrode tabs 114 and 115 of the pouch pack 105 and the connection leads 140 and 145 of the protection circuit module 130 are in contact with each other. The module 130 is fixed. In addition, the jig 200 has a welding hole for moving the lower electrode 310 of the welding device up and down at a position corresponding to a contact position where the electrode tabs 114 and 145 and the connection leads 140 and 145 are in contact with each other. 230 is formed.

The jig 200 is supported and installed to be movable horizontally in a separate frame (not shown).

In addition, the jig 200 may be formed to include a front and rear transfer means 240 for transporting the jig 200 back and forth. When the connecting lead welding apparatus of the lithium secondary battery uses only one electrode, the jig 200 may be moved back and forth to weld each of the electrode tabs 114 and 115 and the connecting leads 140 and 145. Therefore, the jig 200 is moved back and forth by the front and rear transfer means 240 formed by using a transfer mechanism such as a pneumatic cylinder at the bottom of the jig 200.

On the other hand, the jig 200 may be formed on the upper portion of the frame to be manually moved back and forth. In addition, in the connecting lead welding apparatus of the lithium secondary battery according to the present invention, when two pairs of electrodes are used to weld the electrode tabs 114 and 115 and the connecting leads 140 and 145, respectively, the front and rear for moving the jig. Of course, no transport means are required.

The welding part 300 is configured to include a welding rod 310 and the upper high conveying means 320 for transferring the welding rod 310 up and down.

The electrode 310 is a general electrode used for resistance welding, is formed in at least a pair of upper and lower is installed to be located above and below the jig 200. The electrode 310 contacts the electrode tabs 114 and 115 and the connection leads 140 and 145 in a vertical direction to weld them. The electrode 310 may be formed of two pairs of electrodes to enable welding at a time for each of the electrode tabs 114 and 115 and the connection leads 140 and 145 for quickness of the welding process.

The shanghai conveying means 320 is composed of a pneumatic cylinder, a motor and a ball screw and a linear guide or an equivalent conveying means for conveying the welding rod up and down, the welding rod 310 is fixed to the front end and the welding rod 310 up and down Will be transferred to. Therefore, the welding rod 310 is moved up and down by the shanghai conveying means 320 is in contact with the electrode tab (114, 115) and the connection lead (140, 145) to spot weld. The shanghai transport means 320 is installed in the frame 350 is operated.

The foreign material removing unit 400 includes a foreign material suction unit 410, a foreign material collecting container 430, and a vacuum pump 440 and is connected to the electrode tabs 114 and 115 by the welding rod 310. The foreign substances generated when the 140 and 145 are welded are immediately sucked to prevent foreign substances from entering the welded portion.

Referring to FIG. 4, the foreign object suction unit 410 is formed to include a suction pipe 412 through which an inside thereof is extended and an extension part 414 extending in a horizontal direction from an end of the suction pipe 412. The foreign material suction unit 410 is installed in close proximity to the welding position of the electrode tabs 114 and 115 and the connection leads 140 and 145 to suck foreign substances generated during spot welding. The extension portion 414 is preferably formed larger than the length of the contact portion of the pouch pack 105 and the protective circuit module 130 so that the foreign material can be sucked more effectively.

The foreign matter collecting container 430, referring to Figure 5, is formed in a box shape, one side is formed with a suction port 423 is coupled to the connection pipe 420 connected to the foreign object suction portion 410 and the other side A connector 434 to which the vacuum pump 440 is connected is formed. In addition, an opening door 436 for removing the foreign matter collected in the foreign matter collecting container 430 is formed at another side of the foreign matter collecting container 430 to easily remove the collected foreign matter. However, the shape of the foreign material collecting container 430 is not limited thereto, but may be formed in various shapes capable of collecting foreign materials.

At this time, the connecting pipe 420 is preferably formed of a flexible pipe to facilitate the installation position change of the foreign material suction unit 410. In addition, when the connecting pipe 420 is formed of a flexible pipe, even when the jig 200 is moved back and forth, it is possible to be located close to the welding site regardless of the movement of the jig 200.

The vacuum pump 440 is connected to the connector 434 of the foreign matter collecting container 430 to suck the air in the foreign matter suction unit 410 and the foreign matter collecting container 430 while the foreign material suctioning unit 410 ) To inhale foreign matter. Since the vacuum pump 440 does not need to form a high vacuum, preferably a diaphragm pump is used, and various vacuum pumps such as a rotary pump may be used.                     

The controller 500 controls the operation of the shanghai conveying means 320 and the vacuum pump 440, and controls the supply of current to the electrode 310. In addition, when the front and rear transfer means 240 is formed at the bottom of the jig 200, the operation of the front and rear transfer means 240 is removed.

Next, the operation of the connection lead welding apparatus for a lithium secondary battery according to the present invention will be described.

6 is a schematic view showing the action of the connection lead welding apparatus of a lithium secondary battery according to the present invention.

First, the electrode tabs 114 and 115 of the pouch pack 105 and the protection circuit module 130 are disposed in the first and second mounting grooves 210 and 220 formed on the upper surface of the jig 200. The pouch pack 105 and the protection circuit module 130 are seated such that predetermined portions of the connection leads 140 and 145 are in contact with each other.

The control unit 500 operates the shanghai conveying means 320 so that the electrode 310 is in contact with one of the welding position of the electrode tab (114, 115) and the connection lead (140, 145). The control unit 500 supplies electricity to the welding rod when the welding rod contacts the welding position such that the electrode tabs 114 and 115 and the connection leads 140 and 145 are welded to each other. At this time, the control unit 500 operates the vacuum pump 440 of the foreign material removing unit 400 to suck the foreign matter generated in the welding process through the foreign material suction unit 410. The foreign material sucked through the foreign material suction unit 410 is collected in the foreign material collecting container 430. When the foreign material collected in the foreign material collecting container 430 exceeds a predetermined amount, the foreign matter is removed by opening the opening and closing door.

When welding to one of the electrode tabs 114 and 115 and the connection leads 140 and 145 is completed, the jig 200 is moved to move the other electrode tabs 114 and 115 and the connection lead 140 to the other side. 145). At this time, the jig 200 may be moved manually. When the front and rear transfer means 240 is mounted, the jig 200 is operated by operating the front and rear transfer means 240 under the control of the controller 500. Will be moved.

When the movement of the jig is completed is welded through the same process as described above through the same process. In this case, the foreign substances generated in the welding process by the foreign substance removing unit 400 are sucked and removed.

When the welding process is completed, the control unit 500 operates the shanghai conveying means 320 to raise the electrode 310 and stop the operation of the vacuum pump 440.

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 pertains without departing from the gist of the present invention claimed in the claims. Various modifications are possible, of course, and such changes are within the scope of the claims.

According to the connecting lead welding apparatus of a lithium secondary battery according to the present invention, it is possible to quickly remove foreign substances generated in the spot welding process, and the foreign substances are present between the electrode tab and the connecting lead and between the electrode and the connecting lead or the electrode tab. This prevents the welding quality from deteriorating and prevents the coupling between the electrode tab and the connection lead from falling off.

Claims (7)

A jig in which the electrode assembly is provided with a pouch pack accommodated in a pouch case and a protective circuit module welded to the electrode tab by a connection lead such that the electrode tab of the electrode assembly protrudes to the outside; A welding part which is symmetrically formed on the upper and lower parts of the jig, and includes a shang conveying means for transferring a welding rod mounted at each end to a welding position of the electrode tab and the connection lead; A foreign material removal unit installed to be spaced apart from the welding position of the electrode tab and the connection lead by a predetermined distance and sucking and removing foreign substances generated during welding; And And a control unit for controlling the operation of the welding unit and the foreign material removing unit. The method of claim 1, The jig A first seating groove on which the pouch pack is seated and a second seating groove on which the protection circuit module is seated are formed on the upper surface so that a predetermined portion of the electrode tab and the connection lead overlap each other. And a through hole for penetrating at a position corresponding to the welding position to move the welding rod up and down. The method of claim 1, The foreign material removing unit It is characterized in that it comprises a foreign material suction unit is installed close to the welding position and the foreign material suction unit is connected to the foreign material suction portion by a connection pipe to collect the foreign material suction and the vacuum pump connected to the foreign material collection cylinder. Connection lead welding device of a lithium secondary battery. The method of claim 3, wherein The foreign material suction unit Connection lead welding device for a lithium secondary battery characterized in that it comprises an extension portion formed extending in the horizontal direction at the end. The method of claim 3, wherein The foreign material collecting container It includes an opening and closing door formed on one side, the connection lead welding device of a lithium secondary battery, characterized in that formed to enable removal of the collected foreign matter. The method of claim 3, wherein The connecting pipe is a lead welding device of a lithium secondary battery, characterized in that formed as a flexible pipe. The method of claim 3, wherein The vacuum pump is a diaphragm pump connection lead welding device, characterized in that the.

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