WO2008066222A1

WO2008066222A1 - Battery pack

Info

Publication number: WO2008066222A1
Application number: PCT/KR2007/001966
Authority: WO
Inventors: Kil-Tack Woo
Original assignee: Elentec Co., Ltd.
Priority date: 2006-10-20
Filing date: 2007-04-23
Publication date: 2008-06-05
Also published as: KR100685605B1

Abstract

A battery pack according to present invention comprises a battery cell having negative electrode and positive electrode and supplying charged power; a protection circuit module(PCM) for preventing the battery cell from being over-charged or over-discharged; a negative electrode plate coupled to the negative electrode; a holder coupled to the upper portion of the battery cell and having a first opening provided in a portion where the holder is coupled to the electrode of the battery cell; a cover case provided to receive the PCM, the negative electrode plate, and the holder therein and coupled to the battery cell; and a connection plate for electrically connecting the positive electrode and the PCM. By the present invention, the battery pack has such a structure that can prevent the PCM and the positive electrode plate from moving freely. Therefore, the mechanical strength of it can be enhanced.

Description

Description BATTERY PACK

Technical Field

[I] The present invention relates to a battery pack, and more specifically, to an inner- type battery pack of which the mechanical strength is enhanced, and which is easily replaced when defects occur, and overall weight and size of it is reduced.

[2] In general, an inner-type battery pack which is used as a power supply of a mobile communication terminal has a structure that a battery cell and a protection circuit module (PCM) are coupled to each other.

[3] In the battery cell, an electrode- stacked unit composed of a positive electrode sheet and a negative electrode sheet are housed in a metallic casing. On the outer surface of the casing, a positive electrode and a negative electrode are provided.

[4] Further, the PCM for preventing the battery cell from being exploded and overcharged is mounted on the outside of the battery cell.

[5] That is, the battery pack is constructed as one unit in which the battery cell and the

PCM are coupled to each other. As mobile communication terminals using such a battery pack are in trend of reduction in size and weight, there is a demand for the reduction in size, thickness, and weight of the battery pack. Background Art

[6] One example of the battery pack has been disclosed in Japanese Unexamined Patent

Application Publication No. 2002-334686 (hereinafter, referred to as the related art). The battery pack disclosed in the related art includes a battery cell, a protection circuit module (PCM) mounted on the side of the battery cell, and an electrode for electrically connecting the battery cell and the PCM.

[7] The PCM and the electrode are integrally fixed to the battery cell by a molding.

[8] In the battery pack according to the related art, however, since the PCM and the electrode are fixed to the battery cell through the molding portion formed by injection- molding resin, there are considerable difficulties in manufacturing the battery pack.

[9] Further, in such a manufacturing method, when defects occur in the flow of melt resin at a process of forming the molding portion, the strength of the molding portion decreases and cracks or pinholes are generated in the molding portion.

[10] Because of the above-described problems, the PCM can not be satisfactorily protected because the molding portion is easily broken by an external impact.

[I I] Further, in the related art where the PCM and the electrode are integrated with the molding portion, when a defect is found in any one of the PCM and the electrode, the entire integrated PCM and electrode should be replaced. Therefore, a replacement cost increases.

Disclosure of Invention

Technical Problem

[12] An advantage of the present invention is that it can provide a battery pack having a structure which can prevent a protection circuit module (PCM) and a positive electrode from moving freely, thereby it is possible to enhance the mechanical strength of the battery pack.

[13] Another advantage of the invention is that it can provide a battery pack in which a

PCM or an electrode can be easily replaced when a defect is found in the PCM or the electrode. Therefore, it is possible to reduce a replacement cost.

[14] A further advantage of the invention is that it can provide a battery pack in which a separate case for covering the side surface of a battery cell is not used so that the overall weight and size of the battery pack can be reduced. Technical Solution

[15] According to an aspect of the invention, a battery pack comprises a battery cell having negative electrode and positive electrode and supplying charged power; a protection circuit module(PCM) for preventing the battery cell from being overcharged or over-discharged; a negative electrode plate coupled to the negative electrode; a holder coupled to the upper portion of the battery cell and having a first opening provided in a portion where the holder is coupled to the electrode of the battery cell; a cover case provided to receive the PCM, the negative electrode plate, and the holder therein and coupled to the battery cell; and a connection plate for electrically connecting the positive electrode and the PCM.

[16] [0017] Here, the battery pack additionally includes a positive electrode plate and the connection plate is formed in shape of "D" character approximately, and the positive electrode plate is formed in shape of "D" character approximately, one side of the connection plate is coupled to the PCM, and the other side of the connection plate is coupled to a protrusion of the positive plate.

[17] [0018] Preferably, the connection plate is connected to one side of the PCM and is bent so as to be coupled to the positive electrode.

[18] [0019] Preferably, one side of the negative electrode plate is coupled to the PCM, and the other side of it is received in the holder so as to be coupled to the negative electrode of the battery cell through the first opening provided in the holder.

[19] [0020] Preferably, the battery pack further comprises a lower case for protecting the battery cell.

[20] [0021] Preferably, the cover case and the lower case individually include an outer fitting section at the portion where they come in contact with the battery cell, for fixing the battery cell.

[21] [0022] Preferably, the holder has an inserting projection formed thereon and the cover case has an inserting groove formed therein such that the holder and the cover case can be coupled to each other by insertion.

[22] [0023] Preferably, the PCM has a second opening formed in a portion where it is coupled to the negative electrode plate, and the negative electrode plate is coupled to the negative electrode by spot welding.

[23] [0024] Preferably, the holder is provided between the PCM and the battery cell and is supported by the PCM.

[24] [0025] Preferably, the holder is coupled to the upper portion of the battery cell by a both-side tape or adhesive.

[25]

[26]

[27] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[28] Referring to Figs. 1 and 4, a battery pack according to the present invention includes a battery cell 10 having a negative electrode 11 and a positive electrode 13 and supplying charged electrical power, a protection circuit module (PCM) 40 for preventing the battery cell 10 from being over-charged or over-discharged, a negative electrode plate 30 which is coupled to the negative electrode 11, a holder which is coupled to the upper portion of the battery cell 10 and has a first opening 21 formed in a portion where it is coupled to the electrode of the battery cell 10, a cover case 50 which is provided to receive the PCM 40, the negative electrode plate 30, and the holder 20 and is coupled to the battery cell 10, and a connection plate 60 for electrically connecting the positive electrode 13 with the PCM 40.

[29] The battery pack may additionally include a positive electrode plate 35.

[30] Further, the battery pack may additionally include a label sheet 80 which is attached to the side surface of the battery cell 10 so as to prevent the battery cell 10 from moving freely.

[31] Here, the battery pack may additionally include a water submersion label 95 for judging whether water penetrates into the batter cell 10 or not.

[32] Hereinafter, the respective components will be described in details.

[33] Referring to Figs. 1 and 2, a battery pack according to a first example of the present invention has a battery cell 10 including a negative electrode 11. The battery cell 10 is electrically connected to a PCM 40 through a negative electrode plate 30 connected to the negative electrode 11 and a positive electrode plate 35 is coupled to one side of the battery cell 10 such that charged power can be supplied.

[34] Referring to Figs. 4 and 5, a battery pack according to a second example of the present invention has a battery cell 10 including a negative electrode 11 and a positive electrode 13. The battery cell 10 is electrically connected to a PCM 40 through a negative electrode plate 30 connected to the negative electrode 11 and a connection plate 60b connected to the positive electrode 13 such that charged power can be supplied. [35] In the battery cell 10, an electrode-stacked unit composed of negative electrode sheets and positive electrode sheets are housed in a metallic casing. [36] The battery cell 10 may be provided in various types. That is, the battery cell 10 may be provided as a nickel-cadmium battery, a nickel-nitrogen battery, or a lithium ion battery. [37] Preferably, the battery cell 10 is provided as a lithium ion battery which can be charged with a high-capacity voltage for the size thereof, compared with other batteries. After being charged, the lithium ion battery can discharge for a long time.

Further, since the lithium ion battery is composed of one battery, it is convenient to manage. [38] The negative electrode 11 provided in the upper surface of the battery cell 10 is coupled to the negative electrode plate 30 connected to the PCM 40. In the first embodiment of the invention, the positive electrode plate 35 is coupled to one side of the upper surface of the battery cell 10, as shown in Fig. 1. [39] In the second example of the invention, the connection plate 60b is coupled to the positive electrode 13 provided in the other side of the battery cell 10, as shown in Fig.

4. [40] Here, the positive electrode 13 can be formed at one side of upper part of the battery cell 10. That is, the connection plate 60b is electrically connected to the positive electrode 13 provided in one side of the upper surface of the battery cell 10, as shown in Figs. 4 and 5. [41] In the first embodiment, the positive electrode plate 35 can be coupled to the one side of the upper surface of the battery cell 10 in various manners. For example, the positive plate 35 can be coupled by laser welding. [42] Upper portion of the battery cell 10 is coupled with the holder(20). For example, the holder 20 can be coupled to the battery cell 10 by a both-side tape 90 or an adhesives.

In this case, the holder 20 has a first opening 21 provided in a position where the holder 20 is coupled to the electrode of the battery cell 10, such that the negative plate

30 is received in the first opening 21. [43] After the battery cell 10 is coupled to the PCM 40, the negative plate 30, and the holder 20, the battery cell 10 is coupled to a cover case 50 and a lower case 70, as shown in Figs. 1 and 4. In the first example, the battery cell 10 may be coupled to the positive electrode plate 35 so as to be coupled to the cover case 50. [44] The battery pack constructed in such a manner can be protected from an external force. Further, the strength of the battery pack also increases.

[45] The PCM 4 serves to prevent the battery cell 40 from being over-charged or over- discharged. Further, the PCM 4 prevents the battery cell 40 from explosion and an excessive amount of current flowing therein. In addition, the PCM 40 prevents the electrode provided in the battery cell 10 from being short-circuited.

[46] That is, in order to obtain secure protection from the explosion of the battery cell

10, the PCM 40 is mounted on the battery cell 10 when being manufactured. Further, the PCM 40 serves to enlarge the lifetime of the battery cell 10.

[47] In the first embodiment, the PCM 40 is coupled to the positive plate 35 through the connection plate 60a, as shown in Figs. 1 and 2, and the electrical connection with the battery cell 10 can be maintained by the positive electrode plate 35.

[48] In the second embodiment, the PCM 40 is coupled to the positive electrode 13 by the connection plate 60b, as shown in Figs. 4, 5, and 6, and the electrical connection with the battery cell 10 can be maintained by the positive electrode 13.

[49] That is, one side of the connection plate 60b is bent in a direction of an arrow shown in the Fig. 4 so as to be coupled to the positive electrode 13.

[50] In this case, the PCM 40 is coupled to the holder 20 after the connection plate 60b thereof is bent, as shown in Fig. 7. In such a structure, the PCM 40 is prevented from moving freely, and the holder 20 coupled to the PCM 40 is also prevented from moving freely.

[51] The PCM 40 can be coupled to the connection plate 60b in various manners. For example, the PCM 40 can be coupled by soldering or spot welding.

[52] Meanwhile, the PCM 40 is coupled to the negative plate 30, as shown in Figs. 1 and

2 or 4 and 5. The electrical connection of the battery cell 10 with the negative electrode 11 can be maintained by the negative electrode plate 30.

[53] The negative plate 30 can be coupled to the central portion of the PCM 40 in various manners. For example, the negative electrode plate 30 can be coupled by soldering.

[54] Further, the PCM 40 has a second opening 41 formed in a portion where it is coupled to the negative electrode plate 30. Through the opening 41, the negative electrode plate 30 can be coupled to the negative electrode 11 provided on the battery cell 10 by spot welding.

[55] The PCM 40 is coupled to the upper portion of the holder 20 coupled to the battery cell 10. Then, the PCM 40 can be prevented from moving freely. In this case, the holder 20 has the first opening 21 formed in a portion where it is coupled to the electrode of the battery cell 10. Through the first opening 21, the negative electrode plate 30 is received so as to be coupled to the negative electrode 11. [56] The PCM 40 is received in the cover case 50 so as to be prevented from being moved freely and to be protected from an external force. In this case, the cover case 50 additionally includes an outer fitting section 57a such that the PCM 40 is further prevented from moving freely. When the battery pack is wrapped by a label sheet 80, the strength of the battery pack can be increased.

[57] One side of the negative electrode plate 30 is connected to the negative electrode 11 of the battery cell 10, and the other side thereof is coupled to the PCM 40 such that the electrical connection of the PCM 40 with the battery cell 10 can be maintained.

[58] The negative electrode plate 30 may be formed in various shapes. For example, as shown in Figs. 1 and 2 or 4 and 5, a straight metal plate can be bent so as to be connected to both of the PCM 40 and the negative electrode 11.

[59] The negative plate 30 is coupled to the central portion of the PCM 40 such that both ends of the negative plate 30 can be connected to the PCM. In this case, both ends of the negative electrode plate 30 can be coupled to the central portion of the PCM 40 by soldering.

[60] Further, the negative electrode plate 30 can be connected to the negative electrode

11 in various manners. Preferably, the negative electrode plate 30 can be connected through the second opening 41 provided in the PCM 40 by spot welding, in order to facilitate a manufacturing process.

[61] The negative electrode plate 30 can be received in the first opening 21 provided in the holder 20 which is coupled to the battery cell 10. That is, the negative electrode plate 30 is connected to the negative electrode 11 through the first opening 21.

[62] In the first embodiment of the invention, one side of the positive electrode plate 35 which is coupled to the battery cell 10 is coupled to the upper portion of the battery cell 10, and the other side of it is coupled to the connection plate 60a connected to the PCM 40 such that the electrical connection of the PCM 40 with the battery cell 10 can be maintained.

[63] That is, as shown in Fig. 1 or 3, the positive electrode plate 35 is formed in shape of

"D" character approximately such that one side of it is coupled to the battery cell 10. The other side thereof as a protrusion is coupled to the connection plate 60a formed in shape of "D" character approximately.

[64] In this case, the positive electrode plate 35 can be coupled to the connection plate

60a in various manners, for example, by spot welding.

[65] Here, the meaning of said "approximately" is that the positive electrode plate 35 and the connection plate 60a may not necessarily be formed in the above-described shapes such as "D" and "D", and If necessary, the positive electrode plate 35 and the connection plate 60a may be formed in similar shapes to "D" and "D", respectively.

[66] In the meanwhile, the positive plate(35) can be laser welded on upper surface of the battery cell(lθ). And, the positive electrode plate(35) can be made of various materials, for example nickel plate. [67] The holder(20)is connected on upper part of the battery cell(lθ) and support the negative electrode plate(30) and the protection circuit module(40) to prevent them from moving freely. [68] The holder(20) is connected on upper part of the battery cell(lθ) in various way, for example by both-side tape or bonding agent. In this case, first opening(21) can be formed in the holder where the negative electrode is located. [69] Here, the holder(20) receives the negative electrode plate(30) in the first opening(21), and by this first opening(21) the negative electrode(l 1) and the negative electrode plate(30) is connected. [70] The holder(20) and the protection circuit module(40), as seen in Fig.l, Fig.4 to

Fig.7, are connected by the connecting section(27) formed in the two(20, 40). [71] In the first example of this invention, as seen in Fig.l, Fig.2 to Fig.9a, the positive electrode plate(35) and the connection plate(60a) can be connected at outside of the holder(20). [72] Also, in the second example of this invention, as seen in Fig.4, Fig.5 to Fig.9b, the holder(20) can support the connection plate(60b) by being fixed between the positive electrode(13) and the connection plate(60b). [73] Here, as seen in Fig.7, the protection circuit module(40) can be connected to by bending the connection plate(60b). By this, the holder(20) and the protection circuit module(40) can be prevented from moving freely. [74] And, the holder(20), as seen in Fig.9a, can comprise inserting protrusion(51) for inserting connection to the inserting groove(25) in the cover case(50). Namely, the holder(20) can be supported by the cover case(50) for preventing itself from moving freely.

[75] Here, the inserting groove(25) can be formed to penetrate the cover case(50).

[76] IN the meanwhile, as seen in Fig.9, the holder(20) can comprise inserting groove(25) and in this case, the cover case(50) comprises inserting protrusion(51) for inserting connection. [77] Here, it is easer to make mold in actual manufacturing by forming the inserting groove(25) in the inner surface of the cover case(50) than by forming inserting protrusion(51) in the same, and as seen in Fig.9a, it is preferable to form inserting groove(25) in the cover case(50) and inserting protrusion in the holder(20) to reduce error rate. [78] The cover case(50), as seen in Fig.8a, receives the protection circuit module(40), the negative electrode plate(30), the positive electrode plate(35) and the connection plate(60). By this, the cover case(50) can protect the protection circuit module(40), the negative electrode plate(30), the positive electrode plate(35) and the connection plate(60) and prevent them from moving freely.

[79] The cover case(50) can comprise outer fitting section(57a) for being fixed to the battery cell(lθ) in the area contacting with the cell(lθ) and in this case, the outer fitting section(57a) can be 3 milimeter(mm).

[80] Here, the 3 mm is an example and not limited to this, the outer fitting section(57a) can be formed in various length.

[81] In the meanwhile, as seen in Fig.8b, the label sheet(80) can be attached in the area where the outside contact section(57a) and the battery cell(lθ) are connected to prevent the battery cell(lθ) from moving freely.

[82] By this way, mechanical strength of the battery pack can be improved.

[83] The cover case(50), as seen in Fig.9a, can comprise inserting groove(25) for inserting connection with the inserting protrusion(51) in the holder(20). By this, the cover case(50) can support the holder(20) and prevent it from moving freely.

[84] Here, the inserting groove(25) can be formed to penetrate the cover case(50).

[85] The cover case(50) may comprise receiving portion(59) to receive submersion label(95)(for detection under water). Here, the receiving portion(59) can be formed in various part of the cover case(50), for example as seen in Fig.l, can be formed in one side of the cover case(50).

[86] In the first example of this invention, as seen in Fig.l, the connection plate(60a) is formed approximately "D" configuration, and is connected to the positive electrode plate(35) and the protection circuit module(40) to connect the protection circuit module(40) to the positive electrode plate(35) electrically.

[87] That is to say, one side of the connection plate(60a) is connected to protruded portion of the positive electrode plate formed approximately "D" configuration, and the other part of the connection plate(60a) is connected to the protection circuit module(40).

[88] And as seen in Fig.4, in second example of this invention, the connection plate(60b) is bent to connect the PCM(40) with the positive electrode(13), so the PCM(40) is electrically connected with the positive electrode(13) in said battery cell(lθ).

[89] Said connection plate(60) can be made of various materials, for example, nickel plate. Nickel plate has good electrical conductivity and flexibility for bending to connect the connection plate(60b) with the PCM(40) and positive electrode(13).

[90] Here, flexibility is bending characteristic by external force.

[91] And, the connection plate(60) can be made in various shape, as seen in Fig.l, approximately in "□" character shape, or as seen in Fig.4, tetragonal shape.

[92] Said connection plate(60) can be coupled to the PCM(40) in various way, for example, by soldering or spot welding. And, the connection plate(60) can be coupled to the positive electrode plate(35) in various way, for example, by spot welding. [93] Lower case(70) is connected to bottom side of the battery cell(lθ) to protect the cell. [94] Said lower case(70) includes an outer fitting section(57b) at the portion where it comes in contact with the battery cell(lθ), for fixing the battery cell(lθ), and in this case height of the outer fitting section(57b) can be 3 millimeter(mm) approximately. [95] Here, said 3 millimeter is an example and not limited to this height, but it can be formed in various height. [96] In the meanwhile, as seen in Fig.8a and 8b, the outer fitting section(57b) and battery cell(lθ) can be fixed by label sheet(80) attached to a portion where the outer fitting section(57b) and the battery cell(lθ) are connected, to prevent the battery cell(lθ) from moving freely.

[97] By this way, mechanical strength of the battery pack can be improved.

[98] The label sheet(80) is attached around side surfaces of the battery cell(lθ) to improve mechanical strength of the battery pack in the condition that the cover case(50) which receives the PCM(40), the negative electrode plate(30), the positive electrode plate(35) and the holder(20) is coupled to the battery cell(lθ). [99] Here, as seen in Fig.8b, the label sheet(80) wraps the cover case(50) and the outer fitting section(57a, 57b) in lower case(70). [100] The label sheet(80) can comprise at least one of character, image or graphics on it's surface. That is to say, trademark or name of products or manufacturing company can be displayed by the character, image or graphics. [101] Submersion label(95) is for identifying submersion under water, whether the battery pack is submersed under water or not by color change or run over of mark on submersion label(95). [102] The submersion label(95) can be attached in various position in the cover case(50), for example, as seen in Fig.l or Fig.4, can be attached in attaching part(59) in the cover case(50) for identifying submersion under water of the battery pack.

Advantageous Effects [103] According to the present invention, the battery pack has such a structure that can prevent the PCM and the positive electrode plate from moving freely. Therefore, the mechanical strength of it can be enhanced. [104] Further, when defects are found in any one of the PCM and the electrode, the defective part can be easily replaced. Therefore, it is possible to reduce a replacement cost. [105] In addition, since a separate case for covering the side surface of the battery cell is not used, the overall weight and size of the battery pack can be reduced. [106] Further, the cover case for protecting the battery cell can provide excellent strength.

[107] In addition, since the assembling process can be automated, mass production of battery packs can be realized, thereby increasing added value.

Brief Description of the Drawings [108] Fig. 1 is an disassembled perspective view of a battery pack according to a first example of the invention; [109] Fig. 2 is an assembled sectional view of the battery pack according to the first example of the invention; [110] Fig. 3 is a view showing assembling process of connection plate and a positive electrode plate of the battery pack according to the first example of the invention; [111] Fig. 4 is an disassembled perspective view of a battery pack according to a second example of the invention; [112] Fig. 5 is an assembled sectional view of the batter pack according to the second example of the invention; [113] Fig. 6 is a view showing a operational process in which a PCM of the battery pack according to the second example is connected to a positive electrode through a connection plate which is bent; [114] Fig. 7 is a perspective view of the PCM of the battery pack according to the second embodiment, showing a state in which the PCM is coupled to a holder after the connection plate is bent; [115] Fig. 8 is an assembled perspective view of the battery pack according to the invention, showing a state before the battery pack is coupled to a label sheet; [116] Fig. 9 is an assembled perspective view of the battery pack according to the invention, showing a state after the battery pack is coupled to a label sheet; [117] Fig. 10 is a perspective view showing a first exemplary assembling process in which a cover case, a PCM, and a holder of the battery pack are coupled to each other; and [118] Fig. 11 is a perspective view showing a second exemplary assembling process in which a cover case, a PCM, and a holder of the battery pack are coupled to each other.

Mode for the Invention [119] First example

[120] Battery pack according to first example of present invention further comprises positive electrode plate(35), and the connection plate(60a) is formed in shape of "D" character approximately, and the positive electrode plate(35) is formed in shape of "D" character approximately, one side of the connection plate(60a) is coupled to the

PCM(40) and the other side of it is coupled to the protrusion of the positive electrode plate(35). [121] Hereinafter, assembling process of battery pack according to first example of present invention is explained with Fig.l and Fig.8. [122] First, as seen in Fig.l, the positive electrode plate(35) is coupled to one side in upper part of the battery cell(lθ) by laser welding. [123] After, the holder(20) is coupled to the upper part of the battery cell(lθ) by both-side tape(90). In this case, first opening(21) in the holder(20) faces negative electrode(l 1) in upper part of battery cell(lθ), and one side of the holder(20) contact positive electrode plate(35) coupled to one side of the battery cell(lθ). [124] After, by separate process, the negative electrode plate(30) is coupled to center part of the PCM (40), and the connection plate(60a) is coupled to one side of the PCM (40) by soldering or spot welding. [125] After, by said separate process, the PCM(40) which is coupled to the negative electrode plate(30) and the connection plate(60a) is coupled to the holder(20). Here, the negative electrode plate is coupled to the negative electrode through the first opening(21) in the holder(20) which is coupled to the battery cell(lθ). [126] In this case, the PCM(40) is coupled to the positive electrode plate(35) by the connection plate(60a), and coupled to the holder(20) to prevent it from moving freely. [127] Here, the negative electrode plate(30) is coupled to the negative electrode(l 1) by spot welding through the second opening(41) in the PCM(40). [128] And, the connection plate(60a) is coupled to the positive electrode plate(35) by spot welding, and the PCM(40) and the holder(20) are coupled to each other at connection part(27) formed in edge area. [129] In this case, the spot welding for coupling the negative electrode plate(30) to the battery cell(lθ) and spot welding for coupling the connection plate(60a) to the positive electrode plate(35) can be executed at once or by one after the other. [130] Next, as seen in Fig.8a, the battery cell(lθ) which is coupled with the PCM(40), the holder(20), the negative electrode plate(30) and the positive electrode plate(35) is coupled with cover case(50) and lower case(70). In this case, outer fitting section(57a,

57b) on the cover case(50) and the lower case(70) is coupled to the battery cell(lθ). [131] Next, as seen in Fig.8b, the battery cell(lθ) which is coupled with the cover case(50) and the lower case(70) is wrapped by label sheet(80), in this case, the outer fitting section(57a, 57b) is wrapped by the label sheet(80) too. [132] Next, the submersion label(95) is attached on receiving portion(59) in upper part of the cover case(50). [133]

[134] Second example

[135] Battery pack according to second example of present invention is characterized in that the connection plate(60b) which is coupled to one side of the PCM(40) is connected to the positive electrode(13) by bending. [136] Hereinafter, assembling process of battery pack according to second example of present invention is explained in detail with Fig. 8 and Fig.8. [137] First, as seen in Fig.4, the positive electrode(13) is coupled to one side of upper part of the battery cell(lθ) by laser welding. [138] Next, by separate process, the negative electrode plate(30) is coupled to center area of the PCM(40) by soldering, and the connection plate(60b) is coupled to one side of the PCM(40) by soldering or spot welding. [139] Next, by said separate process, the PCM(40) which is coupled with negative electrode plate(30) and the connection plate(60b) is coupled to positive electrode(13) formed in one side of the battery cell(lθ) by the connection plate(60b). [140] In this case, the connection plate(60b) is coupled to the positive electrode(13) by spot welding. [141] Next, the holder(20) is coupled to upper part of the battery cell(lθ) by both-side tape. In this case, the first opening(21) in the holder(20) faces negative electrode(l l) in upper part of the battery cell(lθ), and one side of the holder(20)is coupled to the connection plate(60b) which is coupled to the positive electrode(13). [142] Next, the connection plate(60b) is bent, and the PCM(40) which is coupled to the connection plate(60b) is coupled to the holder(20). Here, the negative electrode plate(30) is coupled to the negative electrode(l 1) through the first opening(21) in the holder(20) which is coupled to the battery cell(lθ). And, the PCM(40) and the holder(20) are connected to each other at connection part(27) formed in one side of them. [143] In this case, the PCM(40) is coupled to the positive electrode(13) by the connection plate(60b), and is coupled to the holder(20) to prevent it from moving freely. [144] Here, the negative electrode plate(30) is coupled to the negative electrode(l 1) formed in the battery cell through second opening(41) in the PCM (40) by spot welding. [145] Next, as seen in Fig.8a, cover case(50) and lower case(70) is coupled to the battery cell(lθ) which is coupled with the PCM(40), the holder(20), the negative electrode plate(30) and the positive electrode plate(35). In this case, the outer fitting section(57a,

57b) in the cover case(50) and the lower case(70) is coupled to the battery cell(lθ). [146] Next, as seen in Fig.8b, the battery cell(lθ) which is coupled with cover case(50) and the lower case(70) is wrapped by label sheet(80), in this case, the outer fitting section(57a, 57b) is wrapped by the label sheet(80) too. [147] Next, submersion label(95) is attached on attaching part(59) in upper part of the cover case(50). [148] Said assembling process of battery pack is an exemplary, the scope of present invention is not limited to said example, and part of the assembling process can be modified.

Claims

[ 1 ] A battery pack comprising: a battery cell having negative electrode and positive electrode and supplying charged electric power; a protection circuit module(PCM) for preventing the battery cell from being over-charged or over-discharged; a negative electrode plate coupled to the negative electrode; a holder coupled to the upper portion of the battery cell and having a first opening provided in a portion where the holder is coupled to the electrode of the battery cell; a cover case provided to receive the PCM, the negative electrode plate, and the holder therein and coupled to the battery cell; and a connection plate for electrically connecting the positive electrode with the

PCM.

[2] The battery pack according to claim 1, wherein the battery pack additionally includes a positive electrode plate, and the connection plate is formed in shape of "D" character approximately, the positive electrode plate is formed approximately in "D" character shape, one side of the connection plate is coupled to the PCM, and the other side of the connection plate is coupled to a protrusion of the positive electrode plate.

[3] The battery pack according to claim 1, wherein the connection plate is connected to one side of the PCM and is bent so as to be coupled to the positive electrode.

[4] The battery pack according to any one of claims 1 to 3, wherein one side of the negative electrode plate is coupled to the PCM, and the other side of it is received in the holder so as to be coupled to the negative electrode of the battery cell through the first opening provided in the holder.

[5] The battery pack according to claim 4 further comprising a lower case for protecting the battery cell.

[6] The battery pack according to claim 5, wherein the cover case and the lower case individually include an outer fitting section at the portion where they come in contact with the battery cell, for fixing the battery cell.

[7] The battery pack according to claim 6, wherein the holder has an insertion projection formed thereon and the cover case has an insertion groove formed therein such that the holder and the cover case can be coupled to each other by insertion.

[8] The battery pack according to claim 7, wherein the PCM has a second opening formed in a portion where it is coupled to the negative electrode plate, and the negative electrode plate is coupled to the negative electrode by spot welding.

[9] The battery pack according to claim 8, wherein the holder is provided between the PCM and the battery cell and is supported by the PCM.

[10] The battery pack according to claim 9, wherein the holder is coupled to the upper portion of the battery cell by a both- side tape or adhesives.