KR20070097150A - Battery pack - Google Patents

Abstract

A battery pack is provided to inhibit an electrolyte discharged from a bare cell from being flowed into a protective circuit module, and thus prevent an electrical short circuit of the protective circuit module caused by a leaked electrolyte. A battery pack includes: many bare cells(210) of which the tops and the bottoms have different polarities; a protective circuit module(220) which is electrically connected to the bare cell; and a case(230) which accommodates the bare cell and the protective circuit module and comprises an upper case(232) and a lower case(234), wherein a barrier(234a) is formed on any one case to separate a protective circuit module space(S2) from a bare cell space(S1). An elastic sealing member(240) is formed between the barrier and the inner surface of the case.

Description

Battery Pack {Battery Pack}

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

FIG. 2 is a partial cross-sectional view of a portion of the battery pack taken along the A-A line in a state before covering the lower case of FIG. 1 with the upper case.

3 is a partial cross-sectional view showing a state before the upper case and the lower case are coupled in the battery pack according to the second embodiment of the present invention.

4 is a partial cross-sectional view showing a state before the upper case and the lower case are coupled in the battery pack according to the third embodiment of the present invention.

5 is a partial cross-sectional view illustrating a state in which an upper case and a lower case are coupled to each other in a battery pack according to a fourth exemplary embodiment of the present invention.

<Brief Description of Major Codes in Drawings>

1: battery pack 10, 110, 210, 310: bare cell

11, 12, 13, 14: conductive plates 15, 16, 17, 18: conductive tabs

20, 120, 220, 320: protective circuit module 25: connector

30, 130, 230, 330: Case 32, 132, 232, 332: Top case

34, 134, 234, 334: lower case 34a, 134a: barrier wall

40,140,240: sealing member 40a, 140a, 240a: coupling groove

232a, 332a: first barrier wall 234a, 334a: second barrier wall

333: first uneven portion 335: second uneven portion

The present invention relates to a battery pack, and more particularly, by improving the structure of a barrier wall formed to separate a bare cell and a protective circuit module in a case, thereby preventing an electrolyte flowing out of the bare cell from flowing into the protective circuit module. The present invention relates to a battery pack capable of preventing an electrical short of a protection circuit module due to electrolyte leakage.

In general, battery packs used in portable electronic devices such as notebooks, personal digital assistants (PDAs), camcorders, and the like are manufactured by tying several bare cells together due to limitations in capacity of bare cells.

The battery pack includes a first case, a plurality of bare cells housed in the first case, a protection circuit module electrically connected to the bare cells to control their charge and discharge states, and covering the first case. And a second case for protecting the bare cell and the protection circuit module from the external environment. Here, the bare cell may be a high capacity cylindrical lithium ion battery. In addition, such battery packs are mounted on notebook computers, personal digital assistants (PDAs), camcorders, and the like, thereby supplying them with predetermined power or being charged by being connected to a charger.

Lithium ion secondary batteries have a risk of being destroyed due to overcharging or overdischarging, and charging and discharging differ from one cell to another. Therefore, particularly in a battery pack using a plurality of lithium ion secondary batteries, a protection circuit such as a circuit for equalizing the state of charge by controlling the charging and discharging for each of all the batteries, or a circuit for preventing over-discharge and overcharging. Often connected. These circuits are formed on a printed circuit board (PCB) of a protective circuit module (PCM) and electrically connected to bare cells by a tab or conductive wire made of nickel (Ni), for example. Is connected.

However, in a conventional battery pack in which batteries and a protection circuit are directly welded or soldered, when a lithium ion secondary battery is destroyed due to over discharge or over charge, an electrolyte solution made of an organic solvent leaks and the protection circuit module (PCM). ) And nickel tabs or conductive wires may cause damage or corrosion. In particular, when the protection circuit module (PCM) is damaged by the electrolyte, it is difficult to control the normal charging and discharging of the battery. In addition, when a short occurs in the protection circuit module PCM, the battery may generate heat or explode.

For this reason, current commercially available battery packs have a barrier in the case that houses them so that the bare cell and the borough circuit module (PCM) are separated. The case is composed of an upper case and a lower case. When the upper case and the lower case are glued together or welded together by welding from the outside, the end of the barrier wall formed inside at least one of the upper case and the lower case has the other end. Contact the end of the barrier wall or the inner wall of the case to form the entire barrier wall in the case.

As described above, the entire blocking wall in the case is formed by physically contacting the end of the blocking wall of one case with the other end of the blocking wall or the inner wall of the case by fusion or welding, but not by fusion bonding or welding. There may be a minute gap in the contact portion where the end of the barrier wall of one case forming a wall and the other end of the barrier wall or the inner wall of the case abut. In a battery pack having such a structure, when flammable organic solvent used as an electrolyte of a bare cell flows out of the bare cell, the spilled electrolyte flows out of a gap in the entire barrier wall of the case, for example, a barrier wall of the upper case and a lower case. The barrier wall flows through the contact portion which is physically in contact with the protection circuit module PCM, causing a short circuit, or contacting a heat source such as a controller chip provided in the protection circuit module PCM. Accordingly, the battery pack as described above has a problem that the reliability of the battery is inferior in reliability.

The present invention is to solve the above-mentioned conventional problems, to improve the structure of the barrier wall formed to separate the bare cell and the protective circuit module inside the case to prevent the electrolyte flowing out of the bare cell to flow to the protective circuit module. Accordingly, an object of the present invention is to provide a battery pack capable of preventing an electrical short of a protection circuit module caused by electrolyte leakage.

The battery pack of the present invention for achieving the above object is a plurality of bare cells having a different polarity of the top and bottom surfaces; An upper and lower barrier wall configured to accommodate a protection circuit module electrically connected to the bare cell, the bare cell and the protection circuit module, and a barrier wall formed in one of the barrier cells to separate the space in which the bare cell is accommodated and the space in which the protection circuit module is accommodated. The case is provided with a combined case,

A sealing member having an elastic force is formed between the blocking wall and the inner surface of the case.

The sealing member may be in close contact with the inner wall of the blocking wall and the case while being contracted between the blocking wall and the inner surface of the case when the upper and lower cases are coupled.

The sealing member may be formed at the end of the blocking wall or on an inner surface of the case corresponding to the end of the blocking wall.

The sealing member may be formed to cover an area including the end of the barrier wall.

The sealing member may include a coupling groove to which the end of the blocking wall is coupled to a surface in contact with the blocking wall.

The sealing member may be made of a rubber (rubber) material, the rubber is a material resistant to the electrolyte, for example, polyphenylene ether (PPE), polyimide (PI), polypropylene (polypropylene; PP), polyester terephthalite PET (polyethyleneterephthalate; PET), polyphenylene sulfide (polyphenylene sulfide PPS), and may be formed of a material containing any one of polyethylene (polyethylene; PE).

Another battery pack of the present invention for achieving the above object is a plurality of bare cells having a different polarity of the top and bottom surfaces; A protection circuit module electrically connected to the bare cell; And a case accommodating the bare cell and the protection circuit module, the upper and lower cases having a barrier wall formed therein to separate the space including the bare cell and the space including the protection circuit module, respectively.

A sealing member having an elastic force is formed at one end of the blocking wall of the upper case and the blocking wall of the lower case.

The sealing member may be formed to cover an end portion of the blocking wall.

The sealing member may be made of a rubber (rubber) material, the rubber is a material resistant to the electrolyte, for example, polyphenylene ether (PPE), polyimide (PI), polypropylene (polypropylene; PP), polyether terephthalate PET (polyethyleneterephthalate; PET), polyphenylene sulfide (polyphenylene sulfide PPS), may be formed of a material containing any one of polyethylene (polyethylene; PE).

Another battery pack of the present invention for achieving the above object is a plurality of bare cells having a different polarity of the top and bottom surfaces; A protection circuit module electrically connected to the bare cell; And a case formed by combining an upper and a lower case to include the bare cell and the protection circuit module.

Concave-convex is formed at an end portion of the barrier wall formed in each of the upper case and the lower case so as to separate the space including the bare cell and the space including the protection circuit module.

The unevenness of the blocking wall integrally formed in the upper case and the unevenness of the blocking wall integrally formed in the lower case may be formed in opposite shapes to engage with each other.

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

1 is an exploded perspective view illustrating a detached battery pack according to a first embodiment of the present invention, and FIG. 2 illustrates a portion of the battery pack cut along the AA line before the lower case of FIG. 1 is covered with the upper case. One part cross section.

As shown in FIG. 1, the battery pack 1 according to the first embodiment of the present invention includes a plurality of bare cells 10 and a protective circuit module (PCM) electrically connected to the bare cells 10. 20)), a case 30 composed of an upper case 32 and a lower case 34 accommodating the bare cell 10 and the protection circuit module 20, and a barrier wall 34a formed in the lower case 34. And a sealing member 40 formed between the inner surface of the case 30.

Each of the bare cells 10 is designed so that the top and bottom surfaces have different polarities. In the drawing, the top surface of the bare cell 10 represents the positive electrode, and the flat bottom surface represents the negative electrode. In addition, it is assumed herein that the top surface of the bare cell 10 is electrically connected to the positive electrode of the electrode assembly (not shown) in the cell, and the bottom surface is electrically connected to the negative electrode of the electrode assembly in the cell. As the bare cell, a cylindrical secondary battery capable of charging and discharging may be used. In particular, a cylindrical lithium secondary battery having a high operating voltage of 3.6 V and a high energy density per unit weight may be used. Although six such bare cells 10 are shown in the drawing, the number thereof is not limited.

In the drawing, B + and B- denote high current stages, and indicate power supply units at both ends of the bare cells 10 connected in parallel and in parallel. B + denotes the highest potential terminal as the positive power supply unit, and B− denotes the lowest potential terminal as the negative electrode power supply unit. A conductive tab for drawing power can be connected to the large current stage, which is indicated by reference numerals 15 and 18 in FIG. 1. For this purpose, the conductive plate may take a substantially "대략" shape. Here, the part "-" of the "ㅗ" shape may be a part fixed by welding to the positive electrode or the negative electrode, and the "ı" part may be a part to which the conductive tab is soldered and fixed.

In addition, B1 and B2 represent a sensing stage, and represent portions in which bare cells of different polarities are connected in series. This sensing stage represents an intermediate potential stage between the highest and lowest potential stages. A conductive tab for voltage detection may be connected to the sensing end, which is indicated by reference numerals 16 and 17 in FIG. 1. For this purpose, the conductive plate may have a substantially "대략" shape before bending. Here, the part "-" of the "ㅗ" shape may be a part fixed by welding to the positive electrode or the negative electrode, and the "ı" part may be a part to which the conductive tab is soldered and fixed.

When the above configuration is described in detail, the first conductive plate 11 is connected to the cathodes of two cells positioned at the lower end of the bare cell, that is, the lowest potential terminal. The second and third conductive plates 12 and 13 have a bent portion, one side of which is fixed to the upper surface of two cells of the bare cells with respect to the bent portion, and the other side of the other two cylindrical bare cells of the cells. It is fixed to the bottom surface to connect the four of the cells in series and in parallel. The fourth conductive plate 14 is connected to the anodes of the two cells located at the upper end of the bare cell, that is, the highest potential terminal. The conductive plate may be any one selected from nickel (Ni), copper (Cu), aluminum (Al), or equivalents thereof, but the material is not limited thereto. And, the conductive plate naturally increases together as the number of bare cells increases.

The protection circuit module 20 is electrically connected to the bare cell 10 through the first to fourth conductive tabs 15, 16, 17, and 18 connected to the first to fourth conductive plates 11, 12, 13, and 14. It is connected, and connected to an external electronic device through the connector 25 to be controlled to prevent over-discharge and overcharge by controlling the charging and discharging of the battery through a circuit (not shown) formed therein. Herein, the first to fourth conductive tabs 11, 12, 13, and 14 may be formed of nickel and may be replaced with a coated wire. Here, the method of electrically connecting the protection circuit module 20 and the bare cell 10 may be used in various ways depending on the shape and type of the bare cell and the protection circuit module used, but the connection method is not limited thereto.

On the other hand, the protection circuit module 20 includes a connector 25 formed in a substantially square hexahedron shape on one surface. The connector 25 includes a body having a plurality of holes (not shown) so as to be electrically connected to and separated from an external electronic device, and a plurality of conductive leads extending to a predetermined length above the inside of the hole and the rear of the body. O). Of course, the body is made of an insulating resin or the like so that the conductive leads are not electrically shorted with each other.

The case 30 accommodating the bare cell 10 and the protection circuit module 20 includes a lower case 34 and a lower case 34 on which the bare cell 10 and the protection circuit module 20 are seated. It comprises a top case 32 covering (). The case 30 may be formed of an insulating material, for example, a plastic material.

The lower case 34 is formed in a box shape having an upper surface open to accommodate the bare cell 10, and a protrusion having a predetermined size to accommodate the protection circuit module 20 and the connector 25 on one side thereof. Is further formed. Here, the protrusion is formed to have an exposed groove so that the connector 25 can be exposed. The upper case 32 is formed in a size corresponding to the upper end of the lower case 34, the upper case 32 is bonded or welded to the upper end of the lower case 34 by an adhesive. Thus, the upper case 32 and the lower case 34 are combined with a protrusion for accommodating the protective circuit module 20 and the connector 25 to form a case 30 forming the appearance of the battery pack. The case 30 has a structure protruding on one side according to the shape of the upper case 32 and the lower case 34, but according to the structure of the battery pack has a structure in which other portions of the case 30 protrude It may be formed in a different shape, of course, may be formed in a shape that does not protrude.

Inside the lower case 34, more specifically, the space S1 including the bare cell 10 and the protection circuit module 20 at least in part between the bare cell 10 and the protection circuit module 20. A plate-shaped blocking wall 34a is formed to separate the space S2 included therein.

At the end of the blocking wall 34a of the lower case 34, as shown in FIGS. 1 and 2, a sealing member 40, which is a feature of the present invention, is formed. At this time, the sealing member 40 is formed in a form covering the area including the end of the blocking wall 34a of the lower case 34, for this purpose, the sealing member in contact with the blocking wall 34a of the lower case 34 The coupling groove 40a to which the end of the blocking wall 34a is coupled to one surface of the 40 is formed. Through the coupling groove 40a, the sealing member 40 may be stably coupled to the end of the blocking wall 34a.

The sealing member 40 as described above is formed of a rubber material having elasticity, a material resistant to the electrolyte, for example, polyphenylene ether (PPE), polyimide (PI), polypropylene (polypropylene) PP), polyether terephthalate (PET), polyphenylene sulfide PPS, and polyethylene (PE).

The reason why the sealing member 40 is formed of an elastic rubber material is that the sealing member 40 blocks the lower case 34 when the lower case 34 and the upper case 32 are joined by a method such as welding from the outside. This is to be pressed between the end of the wall 34a and the inner surface of the upper case 32 so as to be in close contact with the blocking wall 34a end of the lower case 34 and the inner surface of the upper case 32 with high adhesion. Accordingly, the sealing member 40 can remove the minute gap generated when the end of the blocking wall 34a of the lower case 34 and the inner surface of the upper case 32 are combined without a separate member in the middle.

In addition, the reason why the sealing member 40 is formed including a material resistant to the electrolyte is to prevent damage to the electrolyte, which is an organic solvent, when the electrolyte flows out of the bare cell 10.

In order to complete the battery pack with the above-described configuration, the upper case 32 and the lower case in which the bare cell 10 and the protection circuit module 20 are accommodated in the upper case 32 and the lower case 34 ( 34) from the outside, such as by welding. At this time, the sealing member 40 formed at the end of the blocking wall 34a of the lower case 34 is in close contact with the contraction between the end of the blocking wall 34a of the lower case 34 and the inner surface of the upper case 32. Thus, since the sealing member 40 is in close contact with the contraction, it has a high adhesion with the contacting part. Thus, the sealing member 40 has a high adhesion with the contacting portion and forms the entire blocking wall in the case 30 together with the blocking wall 34 of the lower case.

As described above, the battery pack 1 according to the first embodiment of the present invention forms a sealing member 40 having a high adhesion in the middle of the entire blocking wall in the case 30, so that the entire battery in the case in the conventional battery pack It is possible to eliminate the minute gaps present in the physical contact portion of the barrier wall without a separate member. Accordingly, in the battery pack 1 according to the first embodiment of the present invention, when the electrolyte is leaked from the bare cell 10, the leaked electrolyte flows to the protection circuit module through the entire blocking wall in the case 30. You can prevent it. Therefore, it is possible to prevent the electrical short (short) of the protection circuit module due to the leakage of the electrolyte solution to prevent the heat generation and explosion of the battery pack.

In the first embodiment of the present invention, the blocking wall 34a is formed in the lower case 34 so that the sealing member 40 is formed at the end of the blocking wall 34a of the lower case 34, but the blocking wall is formed in the upper case. When formed at 32, a sealing member may be formed at the end of the blocking wall of the upper case 32.

3 is a partial cross-sectional view showing a state before the upper case and the lower case are coupled in the battery pack according to the second embodiment of the present invention.

Compared to the battery pack according to the first embodiment of the present invention, the battery pack according to the second embodiment of the present invention has the same components except that only the position where the sealing member is formed is different. The description of the same components will be omitted.

Referring to FIG. 3, the battery pack according to the second embodiment of the present invention is sealed with a lower case 134 in which the battery cell 110 and the protection circuit module 120 are seated with the blocking wall 134a interposed therebetween. The upper case 132 on which the member 140 is formed is coupled.

The sealing member 140 is formed of a rubber material including a material having elasticity and resistance to the electrolyte, similar to the sealing member 40 of the battery pack according to the first embodiment of the present invention.

The sealing member 140 is formed on the inner surface of the upper case 132 corresponding to the end of the blocking wall 134a of the lower case 134. Here, the lower case 134 is provided on one surface of the sealing member 140 which contacts the end of the blocking wall 134a of the lower case 134 when the upper case 132 and the lower case 134 are joined together by welding or the like from the outside. A coupling groove 140a to which an end of the blocking wall 134a is coupled is formed. The coupling groove 140a is such that the sealing member 140 formed on the inner surface of the upper case 132 covers the end of the blocking wall 134a of the lower case 134 so that the sealing member 140 and the blocking wall 134a are formed. Increase the binding force of the end.

The battery pack according to the second embodiment of the present invention is different from the case in which the sealing member is attached to the end of the blocking wall in the battery pack according to the first embodiment of the present invention. 140) is attached, so the work process is easy.

As described above, the sealing member 140 of the battery pack according to the second embodiment of the present invention is compared with the sealing member 40 of the battery pack according to the first embodiment of the present invention, the upper case 132 and the lower case It is formed of the same material, except that the position formed before the 134 is combined. Accordingly, when the upper case 132 and the lower case 134 are coupled to each other by welding or the like from the outside, the sealing member 140 positioned between the inner surface of the upper case 132 and the ends of the lower case 134. As in the battery pack according to the first embodiment of the present invention, the inner surface of the upper case 132 and the end of the lower case 134 while being contracted are in close contact with high adhesion force. Thus, the sealing member 140 has a high adhesion and forms the entire blocking wall of the case 130 together with the blocking wall 134 of the lower case.

As described above, the battery pack according to the second embodiment of the present invention forms a sealing member 140 having a high adhesion in the middle of the entire blocking wall in the case 130, the center of the entire blocking wall in the case in the conventional battery pack It is possible to eliminate the minute gaps present in the physical contact without a separate member. Accordingly, the battery pack according to the second embodiment of the present invention may prevent the leaked electrolyte from flowing into the protection circuit module through the entire blocking wall in the case 130 when the electrolyte leaks from the bare cell 110. have. Therefore, it is possible to prevent an electrical short of the protection circuit module due to leakage of electrolyte solution, thereby preventing heat generation and explosion of the battery pack.

In the second embodiment of the present invention, although the sealing member 40 is formed on the inner surface of the upper case 132 corresponding to the end of the blocking wall formed on the lower case 134, the blocking wall is formed on the upper case 132 If so, the sealing member may be formed on the inner side of the lower case corresponding to the blocking wall end of the upper case 132.

4 is a partial cross-sectional view showing a state before the upper case and the lower case are coupled in the battery pack according to the third embodiment of the present invention.

Compared to the battery pack according to the first embodiment of the present invention, the battery pack according to the third embodiment of the present invention has the same components except that the entire barrier wall structure of the case including the upper case and the lower case is different. . Thus, the description of the same components will be omitted.

Referring to FIG. 4, a battery pack according to a third embodiment of the present invention includes a battery cell 210, a protection circuit module 220 electrically connected to a bare cell 210, a bare cell 210 and a protection circuit module ( A case 230 including an upper case 232 and a lower case 234 accommodating 220, and a second blocking wall formed on the first and second blocking walls 232a and 234 formed in the upper case 232. It comprises a sealing member 240 formed between the (234a).

The bare cell 210 is included in the lower case 234 where the bare cell 210 and the protection circuit module 220 are seated, more specifically, between the bare cell 210 and the protection circuit module 220. The second blocking wall 234a having a plate shape is formed to separate the space S1 and the space S2 including the protection circuit module 220. In addition, the first blocking wall 232a is formed at a position corresponding to the inside of the upper case 232, more specifically, the second blocking wall 234a of the lower case 234.

The first blocking wall 232a of the upper case 232 and the second blocking wall 234a of the lower case 234 may be coupled to the upper case 232 and the lower case 234 by welding or the like from the outside. Physically coupled to form a total barrier in the case 230.

The sealing member of the present invention is formed between the first blocking wall 232a of the upper case 232 and the second blocking wall 234a of the lower case 234 forming the entire blocking wall of the case 230 as described above. 240 is formed. The sealing member 240 has a coupling groove 240a to which the end of the second blocking wall 234a is coupled to one surface of the lower case 234 so as to cover the end of the second blocking wall 234a. 234a is formed at the end. The coupling groove 240 covers the sealing member 240 formed on the inner surface of the upper case 232 and the end of the second blocking wall 234a of the lower case 234 to seal the sealing member 240 and the lower case ( The coupling force of the second blocking wall 234a of 234 is increased.

In the third embodiment of the present invention, the sealing member 240 is the second blocking wall 234a of the lower case 234 before the upper case 232 and the lower case 234 are joined by a method such as welding from the outside. Although formed at the end, it may be formed at the end of the first blocking wall 232a of the upper case 232.

The sealing member 240 as described above is formed of a rubber material having an elastic force, a material resistant to the electrolyte, for example, polyphenylene ether (PPE), polyimide (PI), polypropylene (polypropylene) PP), polyether terephthalate (PET), polyphenylene sulfide PPS, and polyethylene (PE).

The reason why the sealing member 240 is formed of an elastic rubber material is that the sealing member 240 is made of the upper case 232 when the lower case 234 and the upper case 232 are joined by a method such as welding from the outside. Pressed between the first blocking wall 232a and the second blocking wall 234a of the lower case 234, the end of the first blocking wall 232a of the upper case 232 and the second blocking wall of the lower case 234 ( 234a) for high adhesion to the ends. Accordingly, the sealing member 240 is generated when the end of the first blocking wall 232a of the upper case 232 and the end of the second blocking wall 234a of the lower case 234 are joined without a separate member in the middle. Fine gaps can be removed.

In addition, the reason why the sealing member 240 is formed to include a material resistant to the electrolyte is to prevent damage to the electrolyte, which is an organic solvent, when the electrolyte leaks from the bare cell 210.

In order to complete the battery pack with the above-described configuration, the upper case 232 and the lower case in which the bare cell 210 and the protection circuit module 220 are accommodated in the upper case 232 and the lower case 234 ( 234) from the outside, such as by welding. In this case, the sealing member 240 formed at the end of the second blocking wall 234a formed in the lower case 234 may block the end of the second blocking wall 234a of the lower case 234 and the first blocking of the upper case 232. It is in close contact with the contraction between the ends of the wall 232a. At this time, since the sealing member 240 is in close contact with the contraction, it has a high adhesion with the contacting part. The sealing member 240 has a high adhesion and forms the entire blocking wall of the case 230 together with the first blocking wall 232a of the upper case 232 and the second blocking wall 234 of the lower case 234. .

As described above, the battery pack according to the third embodiment of the present invention forms a sealing member 240 having a high adhesion in the middle of the entire blocking wall in the case 230, the center of the entire blocking wall in the case in the conventional battery pack It is possible to eliminate the minute gaps present in the physical contact without a separate member. Accordingly, the battery pack according to the third exemplary embodiment of the present invention may prevent the leaked electrolyte from flowing into the protection circuit module through the entire blocking wall in the case 230 when the electrolyte leaks from the bare cell 210. have. Therefore, it is possible to prevent the electrical short (short) of the protection circuit module due to the leakage of the electrolyte solution to prevent the heat generation and explosion of the battery pack.

5 is a partial cross-sectional view illustrating a state in which an upper case and a lower case are coupled to each other in a battery pack according to a fourth exemplary embodiment of the present invention.

Compared to the battery pack illustrated in FIG. 4, the battery pack according to the fourth embodiment of the present invention illustrated in FIG. 5 includes the same components except that the entire blocking wall of the case includes an upper case and a lower case. Have Therefore, the description of the same oral elements will be omitted.

As shown in FIG. 5, a battery pack according to a fourth embodiment of the present invention includes a case for receiving a bare cell 310, a protection circuit module 320, and a bare cell 310 and a protection circuit module 320. 330 is made.

The case 330 includes a lower case 334 on which the bare cell 310 and the protection circuit module 320 are seated, and an upper case 332 covering the lower case 334. The case 330 may be formed of an insulating material, for example, a plastic material.

Inside the lower case 334, more specifically, the space S1 including the bare cell 310 and the protection circuit module 320 at least in part between the bare cell 310 and the protection circuit module 320. The second blocking wall 334a having a plate shape is formed to separate the space S2 included therein. In addition, the first blocking wall 332a is formed at a position corresponding to the second blocking wall 334a of the lower case 334 in the upper case 334. The first blocking wall 332a of the upper case 332 and the second blocking wall 334a of the lower case 334 are physically coupled when the upper and lower cases 332 and 334 are combined by welding or the like. It forms a total barrier within 330.

Next, when the upper and lower cases 332 and 334 are coupled, the structure in which the first blocking wall 332a of the upper case 332 and the second blocking wall 334a of the lower case 334 are coupled will be described in detail.

Each of the first blocking wall 332a of the upper case 332 and the second blocking wall 334a of the lower case 334 forming the entire blocking wall of the case 330 as described above may have first unevenness. And second and uneven portions 333 and 335. The first concave-convex portion 333 and the second concave-convex portion 335 are formed in a shape opposite to each other, and are coupled in an engagement form when the upper and lower cases 332 and 334 are coupled to each other. Thus, the first blocking wall 332a of the upper case 332 and the second blocking wall 334a of the lower case 334 are engaged with the first and second uneven parts 333 and 335 so that the case 330 is engaged. It forms a complete barrier inside.

The entire blocking wall in the case 330 is formed by physical contact between the first uneven portion 333 and the second uneven portion 335, and a minute gap may exist in the physical contact portion. However, when the electrolyte is leaked from the bare cell 310, the electrolyte leakage path through which the leaked electrolyte passes through a minute gap formed by the physical contact between the first uneven portion 333 and the second uneven portion 335 is a conventional battery pack. The electrolyte leaked from is longer than the electrolyte leakage path passing through the minute gap formed by the physical contact between the straight blocking wall of the upper case and the straight blocking wall of the lower case. Accordingly, the battery pack according to the fourth embodiment of the present invention can reduce the flow of the electrolyte leaked from the bare cell to the protection circuit module. Therefore, the electrical short of the protection circuit module which may occur due to the electrolyte leakage phenomenon can be prevented, and the safety of the battery can be improved.

As described above, the battery pack according to the present invention forms a sealing member in the middle of the entire blocking wall formed in the case to separate the space containing the bare cell and the space containing the protection circuit module, thereby to be in the case in a conventional battery pack It is possible to remove the minute gaps that existed in the physical contact portion without a separate member of the formed total barrier wall, it is possible to prevent the electrolyte flowed out of the bare cell to the protective circuit module through the minute gaps. As a result, the safety of the battery can be improved.

In addition, the battery pack according to the present invention is formed by irregularities in the coupling portion in the middle of the entire blocking wall in the case, when the electrolyte is leaked from the bare cell, the electrolyte leaked by lengthening the electrolyte leakage path that flows to the protective circuit board It is possible to reduce the flow of the electrolyte to the protective circuit board. Accordingly, the electrical short circuit of the protection circuit module, which may occur due to the electrolyte leakage phenomenon, may be prevented and the safety of the battery may be improved.

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.

Claims (15)

A plurality of bare cells having different polarities at upper and lower surfaces; A protection circuit module electrically connected to the bare cell; A case formed by accommodating the bare cell and the protection circuit module, the upper and lower cases having a blocking wall formed therein so as to separate the space accommodating the bare cell and the space accommodating the protection circuit module; The battery pack, characterized in that the sealing member having an elastic force is formed between the blocking wall and the inner surface of the case. The method of claim 1, The sealing member is a battery pack, characterized in that the close contact with the inner surface of the blocking wall and the case while being contracted between the blocking wall and the inner surface of the case when the upper and lower cases are coupled. The method of claim 1, The sealing member is formed on the end of the blocking wall or battery pack, characterized in that formed on the inner surface of the case corresponding to the end of the blocking wall. The method of claim 3, wherein The sealing member is a battery pack, characterized in that formed to cover the area including the end of the barrier wall. The method of claim 3, wherein The sealing member is a battery pack, characterized in that it comprises a coupling groove coupled to the end of the blocking wall on the surface in contact with the blocking wall. The method of claim 1, The sealing member is a battery pack, characterized in that made of rubber (rubber) material. The method of claim 6, The rubber is a battery pack, characterized in that made of a material resistant to the electrolyte. The method of claim 7, wherein The rubber is polyphenylene ether (PPE), polyimide (polyimide; PI), polypropylene (polypropylene; PP), polyether terephthalate (PET), polyphenylene sulfide (PS) Battery pack, characterized in that formed of a material comprising any one of polyethylene (polyethylene; PE). A plurality of bare cells having different polarities at upper and lower surfaces; A protection circuit module electrically connected to the bare cell; And An upper and lower case having a barrier wall formed therein to receive the bare cell and the protection circuit module, and separating the space including the bare cell and the space including the protection circuit module, respectively; The battery pack, characterized in that the sealing member having an elastic force is formed at one end of the blocking wall of the upper case and the blocking wall of the lower case. The method of claim 9, The sealing member is a battery pack, characterized in that formed in the form covering the end of the blocking wall. The method of claim 9, The sealing member is a battery pack, characterized in that made of rubber (rubber) material. The method of claim 11, The rubber is a battery pack, characterized in that made of a material resistant to the electrolyte. The method of claim 12, The rubber is polyphenylene ether (PPE), polyimide (polyimide; PI), polypropylene (polypropylene; PP), polyether terephthalate (PET), polyphenylene sulfide (PS) , Battery pack characterized in that formed of a material containing any one of polyethylene (PE). A plurality of bare cells having different polarities at upper and lower surfaces; A protection circuit module electrically connected to the bare cell; And And a case formed by combining an upper and a lower case to include the bare cell and the protection circuit module. The battery pack, characterized in that irregularities are formed at the end of the barrier wall formed in each of the upper case and the lower case to separate the space containing the bare cell and the space containing the protective circuit module. The method of claim 14, The unevenness of the blocking wall integrally formed in the upper case and the unevenness of the blocking wall integrally formed in the lower case are formed in an opposite shape to mesh with each other.

Images