KR100760779B1 - Pack battery - Google Patents

Abstract

A pack battery is provided to allow a bare cell to be protected safely against the falling or impact of a pack battery and to reduce the impact transferred to an electrode assembly in case of the application of external force. A pack battery comprises a bare cell(10); a pack case(30) where the bare cell is accommodated; and an adhesive member(40) which is installed at the one side of the bare cell to combine the bare cell and the pack case, wherein the pack battery is provided with a fixing member(50) which is installed at the lower surface of the bare cell to increase the binding force of the bare cell and the pack case. Preferably the fixing member comprises a double-sided adhesive tape or a double-sided adhesive film and has a T shape or a shape of the rectangle whose one side is opened.

Description

Pack battery {PACK BATTERY}

1 is a partially exploded perspective view of a pack battery according to the present invention.

Figure 2 is an enlarged cross-sectional view of a partial cutaway of the adhesive member and the fixing member according to the present invention.

3 is an internal coupling block diagram of a pack battery including a fixing member according to the present invention.

Figure 4a is an embodiment in which the fixing member according to the present invention is installed in the bare cell.

Figure 4b is another embodiment in which the fixing member according to the present invention is installed in the bare cell.

Figure 4c is another embodiment in which the fixing member according to the present invention is installed in the bare cell.

Figure 5 is an internal coupling block diagram of a pack battery containing a conventional adhesive member.

<Explanation of symbols for main parts of the drawings>

10: bearing cell 12: bearing cell case

20: protection circuit board 30: pack case

40: adhesive member 41: adhesive base material

42: adhesive layer 50: fixing member

51: fixing base 52: adhesive layer

The present invention relates to a pack battery, and more particularly, to a pack battery including a fixing member installed on the bottom of the bare cell to increase the coupling force between the bare cell and the pack case.

In general, secondary batteries are rechargeable, unlike disposable batteries, and can be miniaturized and large in capacity. Therefore, due to the advantages of such secondary batteries, attention of the related art industry has recently been focused, and the rapid development of the technology has been developed.

The secondary battery may be classified into a cylindrical battery using a cylindrical aluminum can, a square battery using a square aluminum can, and a pouch type battery housed in a pouch case of a thin plate according to the appearance of a case accommodating an electrode assembly.

Among these, in particular, the pouch type secondary battery is generally composed of an electrode assembly for generating a current, and a pouch case surrounding and sealing the electrode assembly. The electrode assembly is formed by stacking or winding a positive electrode plate and a negative electrode plate through a separator, and having electrode tabs such as positive electrode tabs and negative electrode tabs extending from the respective electrode plates. Each of the electrode tabs is provided such that a protective tape is adhered to a surface thereof to partially protrude out of the pouch case.

 The pouch case includes a pouch case body provided with an inner space to allow the electrode assembly to be seated, and a pouch case cover formed integrally extending from one end of the pouch case body. An edge of the pouch case body is formed to be joined to the pouch case cover and to seal the pouch case body.

In addition, the pouch case is commonly used to insulate the surface of a metal thin plate, such as aluminum thin plate, that is, modified polypropylene, which is a polymer resin, is applied to the aluminum thin plate forming a heat-adhesive layer, the outer surface of nylon or A resin material such as polyethylene terephthalate (PEP) is formed.

Therefore, the use of a thin and flexible pouch as a battery packaging material can significantly reduce the thickness compared to a thick, rigid square or cylindrical can, thereby forming more electrode assemblies in the same volume. That is, the capacity of the battery can be significantly increased, and since the pouch is soft, the battery can be easily manufactured in a desired form, and thus it is easy to be mounted on various electronic devices.

On the other hand, a pack battery generally includes a bare cell that can be charged and discharged, a protective circuit board electrically coupled to the bare cell to control charging and discharging and blocking a circuit during overcharging and discharging, and filling a gap between the bare cell and the protective circuit board. And a pack case configured to pack the bare cell, the protective circuit board, and the resin so as to be mounted on an external set, so that the protective circuit board is not separated from the bare cell.

In order to manufacture such a pack battery, first, the lead is connected to the positive electrode of the bare cell and the PTC thermistor is connected to the negative electrode, and then the protection circuit board is electrically connected to the lead and the PTC thermistor again. Subsequently, the resin is filled in the gap between the protective circuit board and the bare cell so that the protective circuit board is not separated from the bare cell and mechanically fixed, and the pack case is provided so that the protective circuit board can be mounted on an external device. Pack the circuit board. Here, the pack case is molded integrally with another cell together with the bare cell, the protective circuit board and the resin, or the upper case and the lower pack case are prepared respectively, and the integrated bare cell and the protective circuit board are interposed therebetween. After storing, it may be formed wrapped with an exterior material. On the other hand, when moisture is introduced into the pack battery configured as described above, not only the performance of the secondary battery is degraded, but also the durability life of the secondary battery can be significantly shortened.

On the other hand, in configuring the pack battery, when the bare cell is configured with the pouch-type battery described above, that is, when the pouch case cover is joined to the flange of the pouch case body to form the pack battery as a single pouch battery One protective circuit is connected to one pouch battery while the pouch case is turned upside down. That is, the flanges of the side portions of the bonded flanges from which the positive electrode tabs and the negative electrode tabs are not drawn are folded toward the side of the pouch case body, and the derived positive electrode tabs and the negative electrode tabs are folded toward the bottom surface of the inverted pouch case. A protection circuit is connected to electrode tabs such as tabs and negative electrode tabs.

In the conventional general pack battery, as shown in FIG. 5, a double-sided adhesive tape, which is an adhesive member 40, is mainly used to attach the bare cell 10 to the pack case 30. That is, the adhesive member 40 is installed on both sides of the bare cell case 12 to attach the bare cell 10 to the inside of the pack case 30, thereby coupling the bare cell 10 to the inside of the pack case 30. . However, when the pack battery is subjected to a strong shock or a drop test from the outside, a severe shock is transmitted to the electrode assembly inside the bare cell 10 by the flow of the bare cell 10 itself, or the electrode assembly is a bare cell case. Departure from (12) causes the pack battery to be connected to heat generation and smoke generation or more, thereby degrading safety and reliability.

In addition, when the bare cell 10 of the pack battery is configured as a pouch battery, the pouch case has a problem in that the battery capacity is increased and the battery can be processed in various forms. That is, when the pouch pack battery falls freely or is subjected to an external impact, the pouch case may be torn or broken by the flow of the internal electrode assembly, thereby preventing the use of the battery.

Accordingly, the present invention has been made in order to solve the above problems, by installing a fixing member on the bottom surface of the bare cell to increase the coupling force between the bare cell and the pack case, the bare cell when the pack battery is dropped and impacted An object of the present invention is to provide a pack battery that is resistant to impact so that the bare cell is safely protected by preventing the flow of metal.

Another object of the present invention is to change the shape and structure of the fixing member to increase the bonding strength of the bare cell and the pack case, thereby reducing the shock transmitted to the electrode assembly inside the bare cell when the pack battery is subjected to an external force. It is to provide a pack battery.

In order to achieve the above object, the pack battery according to the present invention includes a pack case in which a bare cell and the bare cell are accommodated, and an adhesive member installed on one surface of the bare cell to couple the bare cell and the pack case to each other. In the pack battery is configured, the pack battery is installed on the bottom surface of the bare cell is characterized in that it comprises a fixing member for increasing the coupling force of the bare cell and the pack case.

In this case, the adhesive member may be installed on the front and rear of the bare cell, the fixing member may be composed of a double-sided adhesive tape or a double-sided adhesive film.

In addition, the fixing member may be formed in a shape corresponding to the bottom surface of the bare cell and at least one end may be connected to the adhesive member.

Meanwhile, the fixing member may be formed in a 'T' shape or may be formed in a 'c' shape and installed in the bare cell.

In addition, the bare cell may have a bare cell case formed of a can. In this case, the can may be formed of aluminum or an aluminum alloy. In addition, the bare cell case may be formed of a pouch, wherein the pouch may be formed of aluminum metal foil.

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

According to an exemplary embodiment of the present invention, as shown in FIG. 1, a bare cell 10, a protective circuit board 20 electrically connected to the bare cell 10, and the bare cell ( 10) and the pack case 30 is configured to be mounted on the external device by packing the protective circuit board 20, the adhesive member 40 for coupling the bare cell 10 in the pack case 30 and It is configured to include a fixing member 50 to increase the coupling force of the bare cell 10 and the pack case (30).

In the present embodiment, the bare cell 10 is a pouch-type battery, and includes an electrode assembly charged and discharged with a constant energy and a bare cell case 12 accommodating the electrode assembly, as shown in FIG. 3. do.

The electrode assembly has a shape in which a positive electrode plate, a separator, and a negative electrode plate are stacked to be wound in a jelly roll form. In addition, the positive electrode tab may be formed in the positive electrode plate to be extended to a predetermined length to the outside through the front welding portion while the negative electrode tab is connected to the negative electrode plate. In addition, the protective circuit board 20 for controlling charging and discharging may be connected to each of the electrode tabs exposed to the outside.

The bare cell case 12 is formed in a pouch shape to accommodate and seal the electrode assembly. That is, the bare cell case 12 has a side welded portion formed in an area corresponding to the side of the electrode assembly, and a front welded portion formed in an area corresponding to the front surface of the electrode assembly. In addition, the bare cell case 12 is preferably bent side welded to minimize the appearance.

On the other hand, the bare cell 10 is formed between the electrode assembly and the bare cell case 12 further comprises a support member for coupling the electrode assembly so as not to move or shake inside the bare cell case 12 Of course it can.

In addition, the bare cell 10 may be formed of a rectangular battery or a cylindrical battery in which the bare cell case 12 is formed of a can in another preferred embodiment.

The protective circuit board 20 generally includes a structure having various protective circuits and positive temperature coefficients (PTC) on a printed circuit board (PCB). In addition, a plurality of external terminals exposed to the outside are formed on the surface of the protective circuit board 20.

In addition, the protection circuit board 20 is electrically connected to the electrode tab of the bare cell 10, that is, each electrode tab of the pouch battery according to the present embodiment to control the charge and discharge of the bare cell 10 and overcharge. Break the circuit when discharging. On the other hand, it may be included that the resin is filled in the gap between the bare cell 10 and the protective circuit board 20 to prevent the protective circuit board 20 from being separated from the bare cell 10.

The pack case 30 is integrally formed by molding another resin together with the bare cell 10, the protective circuit board 20, and the resin, or preparing an upper pack case and a lower pack case, respectively, and the integral case therebetween. After the bare cell 10 and the protective circuit board 20 are accommodated, the bare cell 10 and the protective circuit board 20 may be wrapped with an exterior material. In addition, the pack case 30 should be provided with a mounting portion having a complementary shape so that the bare cell case 12 of the pouch battery can be accommodated.

As shown in FIG. 2, the adhesive member 40 has a structure in which an adhesive layer 42 having a predetermined adhesive strength is applied to both surfaces of the adhesive base 41. Therefore, the adhesive member 40 is interposed between one side of the bare cell 10 and the pack case 30 to couple the bare cell 10 to the pack case 30.

On the other hand, the adhesive member 40 may be composed of a double-sided adhesive tape or a double-sided adhesive film or adhesive of the same action.

As shown in FIG. 3, the fixing member 50 is installed on the bottom surface of the bare cell 10 to prevent the bare cell 10 from being separated from the pack case 30. That is, the fixing member 50 is interposed between the bottom surface of the bare cell 10 and the pack case 30 to increase the bonding strength of the bare cell 10 and the pack case 30. Thus, when the pack battery is dropped and impacted, the flow of the bare cell 10 is prevented and safely protected.

On the other hand, the fixing member 50 is preferably composed of a double-sided adhesive tape formed in a structure in which the adhesive layer 52 having a predetermined adhesive strength is applied to both sides of the fixing substrate 51 in the same manner as the adhesive member 40. . At this time, the fixing member 50 may be made of a double-sided adhesive film or adhesive, of course. In addition, the bare cell 10 may be formed of a bare cell case 12 in a can or pouch.

When the bare cell case 12 is a can, that is, when the rectangular or cylindrical pack battery is shocked from the outside, the fixing member 50 is an electrode inside the bare cell 10 due to the flow of the bare cell 10. The assembly is prevented from being separated from the bare cell case 12 to prevent weakening of stability and reliability due to heat generation or abnormal smoke generation of the pack battery. In this case, the can is preferably formed of a common aluminum or aluminum alloy.

In addition, when the bare cell case 12 is a pouch, that is, when the pouch pack battery falls freely or is subjected to an external shock, the fixing member 50 not only enhances the stability and reliability of the pack battery as in the case of the can. Rather, the bare cell case 12, that is, the pouch case is prevented from being torn or broken by the flow of the electrode assembly therein. At this time, the pouch is preferably formed of aluminum metal foil.

Next, various embodiments of the pack battery according to the present invention configured as described above and the operation thereof will be described.

In the pack battery, between the bare cell case 12 in which the electrode assembly is accommodated, and the pack case 30 in which the bare cell 10 is accommodated, specifically, the bottom surface of the bare cell case 12 and the pack case 30. Between the fixing member 50 having the adhesive layer 52 on both sides is interposed, one surface of the fixing member 50 is coupled to the bare cell case 12. Therefore, the bonding force of the bare cell 10 and the pack case 30 primarily coupled by the adhesive member 40 is strengthened secondaryly by the fixing member 50, thereby increasing the bonding force. Therefore, the fixing member 50 prevents the flow of the bare cell 10 when the pack battery is dropped and impacted. Therefore, the fixing member 50 is transmitted to alleviate the external shock to the electrode assembly in the bare cell 10, and prevents the separation to prevent heat generation or smoke abnormality.

Meanwhile, the fixing member 50 may be divided into a lower rounding method, a 'T' shape method and a 'c' shape method as shown in FIGS. 4A to 4C according to the method of being attached to the bare cell case 12. have.

First, FIG. 4A illustrates an example in which the fixing member 50 is installed at the lower rounding, and the fixing member 50 is installed only at the bottom surface of the bare cell case 12. At this time, one end of the adhesive member 40 is installed so as to be located at one end of the front and rear surfaces of the bare cell case 12, one end of the adhesive member 40 is connected to one end of the fixing member 50. Therefore, the adhesive member 40 and the fixing member 50 integrally support the lower portion of the bare cell case 12 and increase the coupling force between the bare cell 10 and the pack case 30. At this time, the fixing member 50 regardless of its shape.

In addition, Figure 4b shows that the fixing member 50 is formed in the 'T' shape is installed in the bare cell 10. In the 'T' shape of the fixing member 50, '-' of 'T' is on both sides of the bare cell 10, '|' is one surface perpendicular to both sides of the bare cell 10 is already installed And, installed on the bottom of the bare cell 10 to increase the coupling force of the bare cell 10 and the pack case (30).

In addition, Figure 4c shows that the fixing member 50 is formed in the '' 'shape is installed in the bare cell (10). The fixing member 50 is formed in a 'c' shape, '|' of 'c' is installed on the bottom surface of the bare cell 10, '-' of the upper and lower portions are respectively provided on both sides of the bare cell 10. The coupling force between the bare cell 10 and the pack case 30 is increased.

Hereinafter, the above-described angles in which the fixing member 50 is installed in comparison with the method in which only the adhesive member 40 is installed on the front and rear surfaces of the bare cell case 12 without the fixing member 50 are attached to the pack case 30. The results of conducting a free fall test test on how the methods affected the bare cell case 12 will be described.

In this free fall test, the pouch pack battery manufactured according to the Examples and Comparative Examples was repeatedly dropped 500 times at a height of 50 cm, followed by 'Opne Circuit Voltage (OCV)' and 'Internal Resistance (IR)'. 'Is measured.

First, as a comparative example, the pouch pack battery provided with only the adhesive member 40 on the front and rear surfaces of the conventional pouch case without the fixing member 50 was subjected to an 'open circuit voltage (OCV: 4,182 mV / internal) when the free fall test was performed. Internal resistance (IR) was 170 mΩ ', and 1 cm tearing occurred at the bottom of the anode side of the pouch case.

The lower rounding method referred to as an embodiment of the present invention is a method in which the fixing member 50 is formed in a shape corresponding to that of the bottom of the pouch case and installed on the bottom of the pouch case. In the test, 'OCV 4,182 mV / IR 167 mΩ', there was no tearing of the pouch case.

As another embodiment of the present invention, the 'T' shape is a method in which the fixing member 50 is installed on the bottom surface of the pouch case, both sides and one side orthogonal to both sides. The test was 'OCV 4,183 mV / IR 160 mΩ', there was no tearing of the pouch case.

In another embodiment of the present invention the 'c'-shaped method is a fixing member 50 is installed on the bottom surface and both sides of the pouch case. The test was 'OCV 4,183 mV / IR 166 mΩ', and there was no tearing of the pouch case.

As described in the above results, when the fixing member 50 is installed on the bottom of the pouch case as in the present invention, it can be seen that the IR value is reduced and the tearing of the pouch case is eliminated. As a result, the pack battery according to the present invention has a fixing member installed on the bottom surface of the bare cell to increase the bonding force between the bare cell and the pack case, so that the bare cell is safely protected when the pack battery is dropped and impacted. Able to know.

The present invention is not limited to the technical spirit of the specific embodiments or drawings described above, and those skilled in the art without departing from the gist of the invention claimed in the claims Various modifications are possible, of course, and such changes fall within the scope of the present invention.

As described above, in the pack battery according to the present invention, the fixing member is installed on the bottom of the bare cell to increase the bonding force between the bare cell and the pack case, so that the bare cell is safely protected when the pack battery is dropped and impacted. There is.

Another effect of the present invention is to change the shape and structure of the fixing member to increase the bonding strength between the bare cell and the pack case, so that the shock transmitted to the electrode assembly inside the bare cell when the pack battery is subjected to an external force is alleviated. .

Claims (10)

A pack battery comprising a bare cell, a pack case in which the bare cell is accommodated, and an adhesive member installed on one surface of the bare cell to couple the bare cell and the pack case to each other, The pack battery, Pack battery, characterized in that it is provided on the bottom surface of the bare cell includes a fixing member for increasing the coupling force of the bare cell and the pack case. The method of claim 1, The adhesive member is a pack battery, characterized in that installed on the front and rear surfaces of the bare cell. The method according to claim 1 or 2, The fixing member is a pack battery, characterized in that consisting of a double-sided adhesive tape or double-sided adhesive film. The method of claim 3, wherein The fixing member is formed with a bottom surface of the bare cell and the corresponding shape surface, at least one end of the pack battery, characterized in that installed in connection with the adhesive member. The method of claim 3, wherein The fixing member is formed in a 'T' shape pack battery, characterized in that installed. The method of claim 3, wherein The fixing member is a pack battery, characterized in that installed in the form of '' '. The method according to claim 1 or 2, The bare cell pack battery, characterized in that the bare cell case is formed of a can. The method according to claim 1 or 2, The bare cell pack battery, characterized in that the bare cell case is formed of a pouch. The method of claim 7, wherein And the can is formed of aluminum or an aluminum alloy. The method of claim 8, The pouch battery pack, characterized in that formed of aluminum metal foil.

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