KR20160013638A - A Secondary Battery Pack having electrical connected groove - Google Patents

Abstract

The present invention provides a battery pack which comprises: a battery cell in which an electrode assembly is sealed in a battery case together with an electrolyte and which has electrode terminals in an upper end thereof; a protection circuit module (PCM) assembly which comprises a PCM, in which a protection circuit for controlling overcharge, overdischarge, and overcurrents is formed, and terminal connection units, which are formed in a lower surface of the PCM to be coupled to connection members; an insulation mounting member which has an opening formed therein to expose the electrode terminals of the battery cell and which is made in a structure for mounting the PCM on an upper portion, and is mounted on an upper end surface of the battery cell; the first and second connection members which electrically connect the electrode terminals of the battery cell to the terminal connection units of the PCM; and an insulating cap which is coupled to an upper portion of the battery cell while surrounding the insulating mounting member when the PCM is mounted. The battery case is composed of a case body and a base plate. An upper end of the case body is opened so that an electrode assembly is inserted. The base plate is coupled to the opened upper end of the case body. The first connection member is directly connected to a protrusion terminal of the base plate and the second connection member is directly connected to an upper end surface of the base plate except the protrusion terminal. A depressed groove for connection is formed in the upper end surface of the base plate, wherein in the depressed groove, a battery cell connection end part of the second connection member is introduced to a portion, where the second connection member is connected.

Description

(A Secondary Battery Pack having an electrically connected groove)

The present invention relates to a secondary battery pack, and more particularly, to a secondary battery pack comprising a battery cell, an insulating mounting member, a protection circuit module (PCM), and connection members, wherein the battery case comprises a case body and a base plate, The upper surface of the base plate is provided with a connection indentation groove for introducing the battery cell connection end of the second connection member at a portion to which the second connection member is connected to reduce the number of members required for manufacturing the battery pack, The present invention relates to a secondary battery pack having a structure capable of reducing the manufacturing cost of the battery and improving the structural stability.

Lithium rechargeable batteries, which have been recently used, have a variety of combustible materials, and thus have a serious safety problem because of the risk of overheating, overcurrent, other physical external impact, and the like. Therefore, the lithium secondary battery is mounted with a protection circuit module (PCM), which is capable of effectively controlling an abnormal state such as overcharging, connected to the battery cell.

Generally, the PCM is connected to the battery cell by welding or soldering. For example, after a clad is attached to some electrode terminals of a battery cell, a nickel plate as a connecting member is welded to a connection terminal of the PCM and an electrode terminal of the battery cell, respectively, A battery pack is manufactured.

The clad is required when the battery case is joined to the positive electrode, which is a battery case, in a rectangular battery cell made of an aluminum can by resistance welding.

To this end, a clad is attached to a corresponding portion of the battery case and one end of the nickel plate is welded to the clad. However, due to the small structure of the battery cell, it is necessary to proceed with precise work, . In addition, there is a problem that the manufacturing cost of the battery pack increases due to the use of the clad.

Therefore, there is a high need for a technique that simplifies the assembly process by reducing the number of members used in manufacturing the battery pack, and minimizes the occurrence of defects during the assembly process.

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above-mentioned problems of the prior art and the technical problems required from the past.

Specifically, it is an object of the present invention to provide a battery pack which can reduce the number of members required for the battery pack and simplify the assembling process, thereby reducing the manufacturing cost of the battery and providing excellent structural stability.

To achieve these and other advantages and in accordance with the purpose of the present invention, as embodied and broadly described herein,

A battery cell in which an electrode assembly is sealed inside a battery case together with an electrolyte solution, and electrode terminals are formed on an upper end thereof;

A protection circuit module (PCM) in which a protection circuit for controlling overcharge, overdischarge, and overcurrent is formed, and terminal connection portions formed on a lower surface of the PCM so that the following connection members are coupled to the PCM assembly;

An insulating mounting member mounted on an upper surface of the battery cell and having an opening to expose an electrode terminal of the battery cell, a protection circuit module mounted on the upper surface of the battery cell,

A first connecting member and a second connecting member for electrically connecting the electrode terminals of the battery cell and the terminal connecting portions of the PCM; And

An insulating cap coupled to an upper end of the battery cell while surrounding the insulating mounting member in a state where the PCM is mounted;

Lt; / RTI >

The battery case includes a case body having a top opened to insert an electrode assembly, and a base plate coupled to an open upper end of the case body,

Wherein the first connecting member is directly connected to the protruding terminal of the base plate and the second connecting member is directly connected to the top surface of the base plate excluding the protruding terminal,

And the upper surface of the base plate is formed with a connecting indentation groove into which the battery cell connecting end of the second connecting member is inserted at a portion to which the second connecting member is connected.

Therefore, in the case of forming a separate connecting indentation groove on the upper surface of the base plate of the battery case as described above, the connecting member electrically connects the PCM and the battery cell by the conductive adhesive without using a separate clad, The battery pack can be easily assembled. Therefore, the secondary battery pack according to the present invention achieves electrical connection of the PCM to the battery cell without a separate clad, so that the manufacturing process can be simplified, and the raw material and personnel can be reduced, thereby reducing the manufacturing cost.

In one specific example, the PCM is perforated with a connecting through-hole, and the first connecting member is coupled to the lower surface of the PCM so that at least a portion thereof can be exposed to the top of the PCM assembly through the connecting through-hole Lt; / RTI >

In the above structure, the electrical connection between the first connection member and the battery cell electrode terminal can be achieved from the top of the PCM with the insulative mounting member and the PCM assembly mounted on the battery cell.

The second connecting member may be configured to protrude from one end of the PCM assembly such that a portion electrically connected to the battery cell may be exposed to an upper portion of the PCM assembly.

In addition, since the secondary battery pack according to the present invention is welded to the connecting member in a state where the PCM is mounted on the battery cell, the connecting member having a relatively long length is connected to the battery cell, The space required for bending the connecting member in the process of mounting the PCM is greatly reduced as compared with the conventional secondary battery pack to be mounted, and the capacity per unit volume of the secondary battery pack can be increased.

In one specific example, the second connecting member may have a structure including a PCM connecting end, a vertically downwardly bent step from the PCM connecting end, and a horizontally bent battery cell connecting end from the step .

In the above structure, for example, the PCM connecting end and the battery cell connecting end may be structured parallel to each other with the stepped portion interposed therebetween, and surplus wrinkles are formed at the bent portion between the stepped portion and the battery cell connecting end Structure. Therefore, the surplus wrinkle can effectively absorb vibration or external impact generated in the battery pack manufacturing process and the welding process.

The first connecting member may be a cathode connecting member, and the second connecting member may be an anode connecting member. For example, a prismatic battery cell has a structure in which an electrode terminal and a battery case protruded from an upper surface thereof are respectively a cathode and a cathode terminal, and an insulating member is interposed therebetween to form mutual insulation. Therefore, the first connecting member connected to the negative terminal, and the second connecting member connected to the upper end surface except for the protruding terminal of the base plate constituting the positive electrode terminal are connected to the circuits in the PCM and the electrode assembly Can be electrically connected.

At this time, the first connecting member and the second connecting member are not particularly limited as long as they are made of a conductive material, but they may preferably be made of nickel or a nickel alloy. It is possible to more easily connect the circuits of the PCM and the electrode assembly inserted into the battery case by using a nickel or nickel alloy having good electrical conductivity and good ductility and softness as the connecting member.

In one preferred embodiment, the insulating mounting member has a size smaller in the longitudinal direction than the upper surface of the battery cell so as to secure a portion where the second connecting member is connected to the battery cell, and the negative terminal of the battery cell is exposed And a second opening exposing the upper end of the case upper end portion of the battery cell (the sealed electrolyte inflow portion) is formed at a predetermined distance from the first opening.

Therefore, since the insulating mounting member is formed to have a smaller length in the longitudinal direction than the upper end surface of the battery cell, a space in which the connecting member A can be positioned between one end of the PCM assembly and one end of the upper end of the battery cell Can be secured.

In addition, since the case body of the battery case requires ease of processing and mechanical strength of a certain level or more, it may be made of a metal can, and preferably an aluminum can or a stainless steel can.

According to the present invention, in a specific example, the connecting indentation groove of the base plate may be formed at a depth of 20 to 150% based on the thickness of the second connecting member.

In one specific example, the connecting indentation groove of the base plate may be formed in a plane with a width of 100 to 150% based on the size of the battery cell connecting end of the second connecting member.

Further, the battery cell connection end of the second connecting member may be connected to the indentation for connection by a conductive adhesive. The conductive adhesive may be made of, for example, a positive filler such as metal or carbon, An epoxy resin adhesive, a urethane resin adhesive, and an acrylic resin adhesive.

The conductive adhesive may be at least one selected from the group consisting of polyvinylidene fluoride, polyvinyl alcohol, carboxymethylcellulose (CMC), starch, hydroxypropylcellulose, regenerated cellulose, polyvinylpyrrolidone, tetrafluoroethylene, ethylene - propylene-diene terpolymer (EPDM), sulfonated EPDM, styrene butylene rubber, and fluorine rubber.

In some cases, an outer film may be attached to the outer surface of the battery case. Thus, the battery cell can be protected from external impact and maintained in an electrically insulated state.

Meanwhile, the secondary battery pack according to the present invention can be applied to various types of battery cells regardless of the type and outer shape of the battery cells, and preferably to a battery pack including a prismatic lithium secondary battery as a battery cell.

The present invention also provides a device including the battery pack as a power source.

The device may be selected from a mobile phone, a portable computer, a smart phone, a tablet PC, a smart pad, a netbook, a wearable electronic device, a notebook computer, and the like. The structure of these devices and their fabrication methods are well known in the art, and a detailed description thereof will be omitted herein.

As described above, in the case where the secondary battery pack according to the present invention is formed with a separate connecting recess groove on the upper surface of the base plate of the battery case, the connecting member is connected to the PCM Since the battery cells are electrically connected, the secondary battery pack can be easily assembled.

In addition, since the secondary battery pack according to the present invention achieves electrical connection of the PCM to the battery cells even without a separate clad, it is possible to reduce the manufacturing cost by simplifying the manufacturing process and reducing the raw materials and personnel.

1 is an exploded perspective view of a secondary battery pack according to an embodiment of the present invention;
2 is a perspective view showing a structure in which a PCM assembly according to an embodiment of the present invention is coupled to a battery cell;
Figure 3 is a cross-sectional view of AB of Figure 2;
4 is a schematic cross-sectional view showing a state in which a PCM connecting end is attached to a connecting indenting groove by a conductive adhesive;
FIGS. 5 to 7 are partial schematic views for explaining a series of processes for assembling the secondary battery pack of FIG. 1 step by step.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings, but the present invention is not limited by the scope of the present invention.

1 is an exploded perspective view of a secondary battery pack according to an embodiment of the present invention.

Referring to FIG. 1, a secondary battery pack 100 includes a battery cell 110 in which an electrode assembly is sealed in a battery case together with an electrolyte, a PCM assembly 120 for effectively controlling an abnormal condition such as overcharging, An insulating mounting member 130 on which the PCM assembly 120 is mounted and mounted on the upper surface 114 of the base plate of the battery cell 110 and an insulating mounting member 130 mounted on the PCM assembly 120 An insulative lower cap 150 coupled to a lower end of the battery cell 110 and an insulative lower cap 150 coupled to the upper end of the battery cell 110 to surround the battery cell 110. [ And a film (160).

A protruding terminal 112 protruding upward from the battery case in a state insulated from the battery case is formed on the upper end surface 114 of the base plate of the battery cell 110. The protruding terminal 112, The other part forms a bipolar terminal. In addition, the electrolyte injection portion 116 sealed with a metal ball, a polymer resin, or the like projects in a circular shape on a plane. A connecting indentation groove 111 is formed on one side of the base plate upper end surface 114 so that the second connecting member 123 is electrically connected.

A structure in which the second connecting member 123 is mounted on the connecting indent groove 111 will be described later.

The insulating mounting member 130 is mounted on and bonded to the upper surface 114 of the base plate of the battery cell 110 in an adhesive manner so that the protruding terminal 112 of the battery cell 110 can be exposed upward A first opening 132 is formed at a central portion of the insulating mounting member 130 and a second opening 134 is formed at a right side portion of the insulating mounting member 130 so that a part of the upper end surface 114 of the base plate of the battery cell 110 is exposed. Is formed.

A second connecting member 123 is coupled to the lower surface of the PCM assembly 120, and a welding through-hole 122 is formed at the central portion.

The insulating upper cap 140 is coupled to the upper end of the battery cell 110 while covering the insulating mounting member 130 in a state where the PCM assembly 120 is mounted and covers the upper end of the battery cell 110 And the A / S label 142 is attached to one side of the upper surface.

The outer surface of the battery case is attached with an outer film 160 for securing an electrically insulated state from the outside and displaying information on the product. The covering film 160 made of a heat-shrinkable material is manufactured in a tube shape and attached to the battery cell 110 in a structure in which the battery cell 110 is wrapped around the battery cell 110,

2 is a perspective view schematically showing a structure in which a PCM assembly is coupled to a battery cell, and FIG. 3 is a schematic cross-sectional view taken along line AB in FIG. 2. FIG. Sectional view showing a state in which the connecting indent groove is mounted on the connecting indent groove.

Referring to FIGS. 2 to 4 together with FIG. 1, a first connecting member 121 and a second connecting member 123 are coupled to a lower surface of the PCM assembly 120. The second connecting member 123 electrically connected to the upper end surface 114 of the base plate of the battery cell 110 includes a PCM connecting end 127, a step 125 bent downward vertically from the PCM connecting end, And a battery cell connection end 124 that is horizontally bent from the step 125. The battery cell connection end 124 protrudes from the outer end of the PCM assembly 120 and has a step 125 And the battery cell connecting end portion 124, surplus corrugations 126 are formed to absorb vibration due to an external impact or the like.

The first connecting member 121 is coupled to the lower surface of the PCM assembly 120 by means of the SMT method in such a manner that the welding through-hole (FIG. 1: 122) is completely sealed.

The second connecting member 123 is brought into contact with the connecting indentation groove 111 formed in the upper end surface 114 of the base plate which is the positive terminal of the battery cell 110 by the conductive adhesive 200, The battery cell 110 and the PCM assembly 120 can be electrically connected to each other because the battery cell assembly 128 is connected to the protruding terminal 112 which is the negative terminal of the battery cell 110. [

5 to 7 are partial schematic views for explaining a series of processes for assembling the secondary battery pack of FIG. 1 step by step.

5 shows the structure in which the insulating mounting member 130 is coupled to the upper end surface 114 of the base plate of the battery cell 110. In FIG 5, The protruding terminal 112 of the battery cell 110 is exposed through the first opening 132 of the insulating mounting member 130 and is exposed to the top, The sealed electrolyte infusion portion 116 of the battery cell 110 is exposed through the second opening 134 to the upper portion of the insulating mounting member 130.

The length l of the insulating mounting member 130 is shorter than the length L of the upper end of the battery cell 110 and the length L of the insulating mounting member 130 is shorter than the length L of the upper end of the upper surface 114 of the base plate of the battery cell 110, And a connecting indentation groove 111 for connecting the second connecting member (Fig. 1: 123) is formed in a part L1.

The length L ₁ of the connecting indent groove 111 is formed to be 110% of the size of the battery cell connecting end 124 of the second connecting member 123 (FIG. 2: W).

6, a structure in which the PCM assembly 120 is coupled to the structure of FIG. 5 is shown. Referring to FIG. 6, after the second connecting member 123 is placed in the connecting recessed groove 111, 200 and the first connecting members 121 are placed on the protruding terminals (FIG. 5: 112) of the battery cells 110, and then electrical connection and mechanical connection structure can be achieved by welding .

7 is a schematic view of a structure in which the insulating upper cap 140 is coupled to the structure of FIG. 6, and FIG. 7 is a schematic view of the insulating upper cap 140, (Not shown) is formed at a position corresponding to the insulative mounting member (not shown), and a fastener (not shown) of the insulating upper cap 140 is fastened to the fastening groove (Not shown) so as to mechanically fasten each other.

Those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims.

Claims (20)

A battery cell in which an electrode assembly is sealed inside a battery case together with an electrolyte solution, and electrode terminals are formed on an upper end thereof;
A protection circuit module (PCM) in which a protection circuit for controlling overcharge, overdischarge, and overcurrent is formed, and terminal connection portions formed on a lower surface of the PCM so that the following connection members are coupled to the PCM assembly;
An insulating mounting member mounted on an upper surface of the battery cell and having an opening to expose an electrode terminal of the battery cell, a protection circuit module mounted on the upper surface of the battery cell,
A first connecting member and a second connecting member for electrically connecting the electrode terminals of the battery cell and the terminal connecting portions of the PCM; And
An insulating cap coupled to an upper end of the battery cell while surrounding the insulating mounting member in a state where the PCM is mounted;
Lt; / RTI >
The battery case includes a case body having a top opened to insert an electrode assembly, and a base plate coupled to an open upper end of the case body,
Wherein the first connecting member is directly connected to the protruding terminal of the base plate and the second connecting member is directly connected to the top surface of the base plate excluding the protruding terminal,
Wherein a connecting indentation groove is formed in an upper end surface of the base plate to connect the battery cell connecting end of the second connecting member to a portion to which the second connecting member is connected. 2. The PCM according to claim 1, wherein a connection through hole is drilled in the PCM, and the first connection member is coupled to a lower surface of the PCM so that at least a part of the connection member can be exposed to the upper portion of the PCM assembly through the connection through- Wherein the battery pack is a battery pack. The battery pack according to claim 1, wherein an electrical connection between the first connecting member and the battery cell electrode terminal is achieved from the top of the PCM with the insulating mounting member and the PCM assembly mounted on the battery cell. The battery pack according to claim 1, wherein the second connecting member protrudes from one end of the PCM assembly so that the battery cell connecting end is exposed from the top of the PCM assembly. 2. The battery module according to claim 1, wherein the second connecting member includes a PCM connecting end, a stepped portion vertically bent downward from the PCM connecting end, and a battery cell connecting end horizontally bent from the stepped portion . The battery pack according to claim 5, wherein the PCM connecting end and the battery cell connecting end are parallel to each other with a stepped portion therebetween. The battery pack according to claim 5, wherein a surplus wrinkle is formed at a bent portion between the step portion and the battery cell connecting end. The battery pack according to claim 1, wherein the first connecting member is a negative electrode connecting member, and the second connecting member is a positive electrode connecting member. The battery pack according to claim 1, wherein the first connecting member and the second connecting member are made of nickel or a nickel alloy, respectively. The battery pack of claim 1, wherein the insulating mounting member has a size smaller than a top surface of the battery cell in the longitudinal direction so as to secure a portion to which the second connecting member is connected to the battery cell, And a second opening is formed at a predetermined distance from the first opening to expose a case upper projection portion of the battery cell ('sealed electrolyte injection portion') upwardly. The battery pack according to claim 1, wherein the case body of the battery case is a metal can. The battery pack according to claim 1, wherein the connecting indentation groove of the base plate is formed at a depth of 20 to 150% based on the thickness of the second connecting member. The battery pack according to claim 1, wherein the connecting indentation groove of the base plate is formed to have a width of 100 to 150% on the basis of the size of the battery cell connecting end of the second connecting member in plan view. The battery pack according to claim 1, wherein the battery cell connecting end of the second connecting member is connected to the connecting recessed groove by a conductive adhesive. 15. The battery pack according to claim 14, wherein the conductive adhesive is made of an epoxy resin adhesive, a urethane resin adhesive, or an acrylic resin adhesive including a positive filler such as metal or carbon. . 15. The method of claim 14, wherein the conductive adhesive is selected from the group consisting of polyvinylidene fluoride, polyvinyl alcohol, carboxymethylcellulose (CMC), starch, hydroxypropylcellulose, regenerated cellulose, polyvinylpyrrolidone, tetrafluoroethylene Wherein the battery pack is made of one or a combination of two or more selected from the group consisting of ethylene, ethylene-propylene-diene terpolymer (EPDM), sulfonated EPDM, styrene butylene rubber, and fluorine rubber. The battery pack according to claim 1, wherein an outer film is attached to an outer surface of the battery case. The battery pack according to claim 1, wherein the battery cell is a prismatic lithium secondary battery cell. 19. A device comprising at least one battery pack according to any one of claims 1 to 18. 20. The device of claim 19, wherein the device is a mobile phone, a portable computer, a smart phone, a tablet PC, a smart pad, a netbook, a wearable electronic device, or a notebook computer.

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