KR100659857B1 - Pack case of secondary battery - Google Patents

Abstract

Provided is a pack battery which is reduced in the manufacturing cost of a pack case by decreasing the area surrounded by a pack case and is simplified in the manufacturing process of a pack case. The pack battery comprises a secondary battery which is provided with a safety device and an external terminal; and a pack case(400) which is separated into at least two parts so as to surround the narrow side of the secondary battery along the circumference. Preferably the pack case comprises a first case(410) and a second case(420) which are combined by a bonding part, and the bonding part comprises a bonding projection(411) which is formed at the terminal of the first case, and a bonding groove which is formed at the terminal of the second case so as to correspond go the bonding projection.

Description

PACK CASE OF SECONDARY BATTERY {PACK CASE OF SECONDARY BATTERY}

1 is a view showing an embodiment of a battery pack in which a bare cell is mounted in a pack case according to the present invention,

2 is an exploded perspective view showing a pack case of a secondary battery according to the present invention,

3 is a perspective view showing a pack case of a secondary battery according to the present invention.

The present invention relates to a pack case of a secondary battery, and more particularly, to a pack case in which a secondary battery is mounted.

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. Representative secondary batteries include lithium secondary batteries such as nickel-cadmium (Ni-Cd) batteries, nickel-hydrogen (Ni-MH) batteries, lithium (Li) batteries, and lithium ion (Li-ion) batteries.

Most of the unit cells in these secondary batteries are formed by accommodating an electrode assembly consisting of a positive electrode, a negative electrode, and a separator in a can made of aluminum or an aluminum alloy, closing the can with a cap assembly, and then injecting and sealing an electrolyte into the can. . The can may be formed of iron, but when it is formed of aluminum or an aluminum alloy, the light may be lightened by the light property of aluminum, and may not be corroded even when used for a long time under high voltage.

A battery pack constructed by using a plurality of such unit cells generally includes a plurality of batteries, wiring circuits for electrically connecting these batteries, safety elements, and contact terminals in a battery pack container (case) having battery insulation. It is a structure.

That is, the sealed unit cell is stored in a separate pack while being connected to safety devices such as a PTC element, a thermal fuse, a protective circuit module (PCM) and other battery parts. do. Alternatively, the unit cell, the protective circuit board, and the other battery parts are connected to each other, and the gap therebetween is filled with the molding resin, and fixed or coated together to form a pack battery.

Safety devices are connected to the positive and negative terminals of the unit cell by a conductor structure called a lead, and the battery breaks when the voltage of the battery suddenly rises due to the high temperature of the battery or excessive charge and discharge. Back to prevent danger.

Such a secondary battery has a standard that can be accommodated in a pack case and mounted on an electronic device.

Here, the pack case accommodates safety devices including a bare cell, a protective circuit board, and the like, and forms a pack battery by molding the molding material so that external terminals connecting them to the outside are exposed. That is, the pack battery requires a hard case sized to accommodate bare cells and safety devices.

The present invention has been made to solve the above problems, an object of the present invention is to provide a pack battery that can be provided by providing a pack case that can accommodate the safety devices including a bare cell and a protective circuit board, etc. will be.

The present invention for achieving the above object provides a pack battery including a secondary battery provided with a safety device and an external terminal and a pack case separated into at least two so as to surround the narrow surface of the secondary battery in a rim.

The pack case may include a first case and a second case to form a frame when the first case and the second case are combined.

The pack case is coupled by a coupling part, and the coupling part may include a coupling protrusion formed to protrude on an end side of the first case, and a coupling groove formed on an end side of the second case and corresponding to the coupling protrusion. .

The coupling part may include a first uneven groove formed at an end side of the first case and a second uneven groove formed at an end side of the second case and formed to correspond to the first uneven groove.

The secondary battery may be rectangular, cylindrical, or pouch type.

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

1 is a view showing an embodiment of a battery pack equipped with a bare cell in the pack case according to the present invention, Figure 2 is an exploded perspective view showing a pack case of a secondary battery according to the present invention, Figure 3 Combined perspective view showing a pack case of a secondary battery according to the invention.

As shown in these figures, the pack battery includes a bare cell 300, a protection circuit module 390, and a pack case 400.

The bare cell 300 includes an electrode assembly 250 and a case 200 for receiving the electrode assembly 250.

The electrode assembly 250 is interposed between the first and second electrode plates 210 and 220 coated with the first and second electrode active material layers, and the first and second electrode plates 210 and 220, respectively. Separator 230 is wound around to prevent a short circuit and to allow only ion movement of the electrolyte. First and second electrode tabs 215 and 225 are drawn out to the first and second electrode plates 210 and 220, respectively.

In this case, the first electrode plate 210 may be a cathode, and the second electrode plate 220 may be an anode.

Here, the first electrode plate 210 includes a conductive metal plate, such as a negative electrode current collector made of copper foil, and a negative electrode active material layer mainly composed of a carbon material coated on both surfaces thereof. The negative electrode terminal is connected to the region of the negative electrode current collector in which the negative electrode active material layer is not formed in the negative electrode, and is led out. As the negative electrode active material, carbon (C) -based materials, Si, Sn, tin oxides, composite tin alloys, transition metal oxides, and lithium metal oxides are used.

The second electrode plate 220 includes a positive electrode current collector made of a thin metal plate having excellent conductivity such as aluminum foil, and a positive electrode active material layer coated on both surfaces thereof and containing a lithium oxide as a main component. The positive electrode is led out to the upper side of the positive electrode terminal electrically connected to a region of the positive electrode current collector where the positive electrode active material layer is not formed. Chalcogenide compounds are used as the positive electrode active material, and complex metal oxides such as LiCo02, LiMn204, LiNi02, LiNi1-xCox02 (0 <x <1), and LiMn02 are used.

The separator 230 is formed to be wider than the first and second electrode plates 210 and 220, which is advantageous in preventing short circuits between the electrode plates. In addition, the separator 130 may be generally made of polyethylene (PE) or a copolymer of polypropylene (PP) polyethylene and polypropylene (Co-Polymer), but the material is not limited thereto.

The case 200 may have a cylindrical shape, a rectangular can, or a pouch type.

In the present embodiment shown in FIG. 1, the case 200 is formed of aluminum or an aluminum alloy having a substantially rectangular box shape to accommodate the electrode assembly 250 and the electrolyte through the opening 201 of the case 200. . The case 200 may itself serve as an electrode terminal of any one of the first and second electrodes 215 and 225.

The cap assembly 100 is a case 200 covers and seals the opening 201, and is provided with a flat cap plate 110 having a size and a shape corresponding to the opening 201 of the case 200. . An insulating plate 140 is installed on the lower surface of the cap plate 110, and a terminal plate 150 electrically connected to the first electrode tab 215 provided on the first electrode plate 210 on the lower surface of the insulating plate 140. ) Is installed.

The cap plate 110 has a first terminal through-hole 111 connected to the first electrode tab 215 by penetrating the electrode terminal 130 at a central portion thereof, and an electrode terminal 130 in the first terminal through-hole 111. A tubular gasket 120 is installed to electrically insulate the cap plate 110 from each other.

The safety plate 117 is formed on the cap plate 110. Safety vent 117 is generally formed on the upper surface of the cap plate 110 and may be in the form of a groove formed thinner than the thickness of the cap plate (110).

The insulating plate 140 is formed of an insulating material such as the gasket 120 and is coupled to the bottom surface of the cap plate 110. The insulating plate 140 is formed to correspond to and communicate with the first terminal through-hole 111 of the cap plate 110 is a second terminal through-hole 141 is formed.

The terminal plate 150 is formed of Ni metal or an alloy thereof, and is coupled to the lower surface of the insulating plate 140. The terminal plate 150 has a third terminal through hole 151 corresponding to the first terminal through hole 111 of the cap plate 110.

In addition, the insulating case 160 is installed on the upper side of the electrode assembly 250 to insulate the electrode assembly 250 and the cap plate 110, the material of the insulating case 160 is a polymer resin having insulation, Preferably it is made of polypropylene, but the material is not limited in the embodiment of the present invention.

The first and second electrode tabs 215 and 225 drawn from the electrode assembly 250 are connected to the cap plate 110 and the electrode terminal 130, and the cap plate 110 and the electrode terminal 130 are respectively first and second. The protective circuit board 390 is connected to the electrode leads 360 and 370.

The protection circuit board 390 controls the charge / discharge of the bare cell 300 by blocking the charge / discharge current or increasing the electrical resistance when the bare cell 300 is abnormally operated. 391).

Here, the electrode terminal 130 connected to the first electrode plate 210 becomes a cathode, and the cap plate 110 and the case 200 connected to the second electrode plate 220 become an anode. Thus, an insulating member 177 is installed on the upper surface of the cap plate 110, and a connection lead 380 is installed on the upper side of the insulating member 177 to connect the electrode terminal 130 and the first electrode lead 360. When the cap plate 110 and the connecting lead 380 having a different polarity is insulated.

Pack case 400 is formed in a rectangular frame shape to surround the narrow surface of the bare cell 300 made as described above in a border form and is separated into first and second cases 410 and 420.

The first case 410 and the second case 420 are coupled by the coupling portion.

The coupling part is formed to correspond to the coupling protrusion 411 so that the coupling protrusion 411 formed to protrude on the end side of the first case 410 and the coupling protrusion 411 on the end side of the second case 420. It consists of a coupling groove (421).

Here, the coupling protrusion 411 and the coupling groove 421 may be the first and second uneven grooves correspondingly formed, although not shown. In other words, the first and second uneven grooves may be formed to engage with each other when the first case 410 and the second case 420 are coupled to each other.

In this case, one of the first case 410 and the second case 420 may be formed with an external terminal hole 413 for exposing the external terminal 391 of the protective circuit board 390.

Hereinafter, the assembly process of the secondary battery according to the present invention configured as described above will be described in detail.

First, the case 200 accommodates the electrode assembly 250. The case 200 is formed in a square.

An insulating case 160 is installed above the electrode assembly 250. In this case, the first and second electrode tabs 215 and 225 drawn out from the electrode assembly 250 are drawn out of the case 200 through the insulating case 160.

Next, the cap plate 110, the insulating plate 140, and the terminal plate 150 are sequentially stacked such that the first, second, and third terminal through holes 111, 141, and 151 communicate with each other. The cap plate 110, the insulating plate 140, and the electrode terminal 130 penetrating the terminal plate 150 are inserted into the first, second, and third terminal through-holes 111, 141, and 151 which are in communication with each other. Let's do it.

In this case, the electrode terminal 130 is insulated from the cap plate 110 by the gasket 120 and coupled through the first terminal through hole 111 of the cap plate 110, so that the terminal plate 150 is the cap plate 110. It is electrically insulated from and electrically connected to the electrode terminal 130.

The cap assembly 100 assembled as described above seals the opening 201 of the case 200. Here, the electrode terminal 130 and the cap plate 110 connected to the first and second electrode tabs 215 and 225, respectively, are protected circuit boards 390 through the first and second electrode leads 360 and 370 and the connection lead 380. Connected with

The bare cell 300 assembled as described above is coupled to the first case 410 and the second case 420 divided into upper and lower portions by surrounding the edge portion thereof by a coupling part. That is, the coupling protrusion 411 of the first case 410 is inserted into the coupling hole 421 formed in the second case 420 to couple the first case 410 and the second case 420.

Next, resin may be injected between the protective circuit board 300 and the cap plate 110 to strengthen the coupling of the bare cell 300 and the pack case 400.

Therefore, the bare cell 300 may be formed of a pack battery standardized by the pack case 400.

The present invention has the advantage that the pack case is formed so as to surround only the edge portion of the bare cell in a frame shape than the pack case surrounding the wide surface of the bare cell, and the manufacturing process of the pack case is simplified.

As described above, the present invention is not limited to the specific preferred embodiments described above, and those skilled in the art without departing from the gist of the present invention as claimed in the following claims. As long as anyone can carry out various modifications, such changes are within the scope of the claims.

Claims (9)

A secondary battery provided with a safety device and an external terminal; And Pack battery including a pack case separated into at least two so as to surround the narrow surface of the secondary battery in a rim. The method of claim 1, The pack case comprises a first case and a second case pack battery, characterized in that when the first case and the second case is combined to form a frame shape. The method of claim 2, The pack case is characterized in that the battery pack is coupled by a coupling portion. The method of claim 3, wherein The coupling part is a coupling protrusion formed to protrude on the end side of the first case; And, And a coupling groove formed at an end side of the second case and formed to correspond to the coupling protrusion. The method of claim 3, wherein The coupling portion is a first uneven groove formed on the end side of the first case; And, And a second uneven groove formed at an end side of the second case and formed to correspond to the first uneven groove. The method of claim 2, Pack battery, characterized in that the external terminal hole for exposing the external terminal of the secondary battery is formed in any one of the first case and the second case. The method of claim 1, The secondary battery is a pack battery, characterized in that the cylindrical. The method of claim 1, The secondary battery is a pack battery, characterized in that the pouch type. The method of claim 1, The secondary battery is a pack battery, characterized in that the square.

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