Title of the invention: Bus bar for connecting battery cells, battery pack, and manufacturing method thereof
Technical field
[One]
The present invention relates to a battery cell connection bus bar, a battery pack, and a manufacturing method thereof, and more particularly, to a battery cell connection bus bar for electrically connecting a plurality of battery cells, a battery pack, and a manufacturing method thereof. .
[2]
Background
[3]
In general, a secondary battery refers to a chemical battery capable of repeatedly charging and discharging by using reversible mutual conversion of chemical energy and electrical energy. High-performance secondary batteries include Ni-MH secondary batteries and lithium secondary batteries, and lithium secondary batteries include lithium metal secondary batteries, lithium ion secondary batteries (square, cylindrical, pouch type), and lithium ion polymer secondary batteries.
[4]
As the spread of information technology (IT) products with convenient mobility such as mobile phones, notebook computers, and PDA (Personal Digital Assistants) are expanding, the demand for small-sized secondary batteries is rapidly increasing worldwide, centering on lithium-based secondary batteries. , Among them, lithium ion secondary batteries or lithium ion polymer secondary batteries are leading the market according to the demand for miniaturization, weight reduction, and high performance of IT devices.
[5]
The secondary battery is sometimes used in the form of a single battery cell or a battery pack in which a plurality of unit battery cells are electrically connected, depending on the type of external device in which it is used. For example, small devices such as mobile phones can operate for a certain period of time with the power and capacity of a single battery cell, while medium-sized devices such as notebook computers, portable DVDs, small PCs, electric vehicles, and hybrid electric vehicles. Alternatively, large devices require the use of a battery pack due to issues of output and capacity.
[6]
In order to electrically connect a plurality of battery cells, the battery pack includes a bus bar made of a metal plate, etc., and the bus bar has a plurality of leads extending to one side or both sides, respectively, welded to the electrode terminals of the battery cells. A plurality of battery cells are electrically connected.
[7]
However, if a welding failure occurs between the bus bar and the electrode terminal of the battery cell during the welding process, a problem in that the manufactured battery pack must be disposed of entirely occurs. The larger the capacity of the battery pack, the greater the number of battery cells to which the electrode terminals are to be welded, and thus, when the entire battery pack is disposed of, a large loss occurs in terms of cost. In order to solve such a problem, a method of minimizing welding defects is also necessary, but when a welding defect occurs, there is an urgent need to prepare a method to prepare for this.
[8]
(Prior technical literature)
[9]
KR10-2016-0059789A
[10]
Detailed description of the invention
Technical challenge
[11]
The present invention provides a battery cell connection bus bar, a battery pack, and a method of manufacturing the same, capable of electrically stably connecting a plurality of battery cells even when a welding failure occurs.
[12]
Means of solving the task
[13]
A bus bar for connecting a battery cell according to an embodiment of the present invention includes a body made of a conductive material; A lead portion extending from the body portion; A first welding protrusion protruding from the lead part to be welded to the electrode terminal of the battery cell; And a second welding protrusion protruding from the lead part to be welded to the electrode terminal, wherein the second welding protrusion is formed to protrude lower than the first welding protrusion.
[14]
Each of the first welding protrusion and the second welding protrusion may be formed to face the electrode terminal.
[15]
[16]
On the other hand, a bus bar for connecting a battery cell according to an embodiment of the present invention includes a body made of a conductive material; A lead portion extending from the body portion; A first welding protrusion protruding from the lead part to be welded to the electrode terminal of the battery cell; And a second welding protrusion protruding from the lead part to be welded to the electrode terminal, wherein the second welding protrusion is formed to protrude in a direction different from the protruding direction of the first welding protrusion.
[17]
The lead part may include a first lead facing an electrode terminal of the battery cell; And a second lead bent and disposed from the first lead, wherein the first welding protrusion and the second welding protrusion may be formed on the first lead and the second lead, respectively.
[18]
The second welding protrusion may be disposed closer to the body portion than the first welding protrusion.
[19]
A guide groove may be formed on at least one surface of the lead portion in a direction crossing the extending direction from the body portion.
[20]
The guide groove may include: a first guide groove positioned between the first welding protrusion and the second welding protrusion; And a second guide groove positioned between the second welding protrusion and the body portion.
[21]
At least one of the first guide groove and the second guide groove may be formed in a plurality.
[22]
[23]
In addition, a battery pack according to an embodiment of the present invention includes a plurality of battery cells; And a bus bar for electrically connecting the plurality of battery cells, wherein the bus bar includes: a lead portion extending over an electrode terminal of the battery cell; A first welding protrusion formed on the lead portion and bonded to the electrode terminal; And a second welding protrusion formed on the lead portion and disposed to be spaced apart from the electrode terminal.
[24]
Each of the first welding protrusion and the second welding protrusion may be formed to face the electrode terminal, and the second welding protrusion may be formed to protrude lower than the first welding protrusion.
[25]
The lead part may include a first lead facing an electrode terminal of the battery cell; And a second lead bent and disposed from the first lead, wherein the first welding protrusion and the second welding protrusion are respectively formed on the first lead and the second lead to protrude in different directions.
[26]
A plurality of lead portions may be provided, and at least two lead portions of the plurality of lead portions may extend onto the electrode terminal.
[27]
[28]
In addition, a method of manufacturing a battery pack according to an embodiment of the present invention includes: welding a first welding protrusion protruding from a lead portion to an electrode terminal of a battery cell; Checking a welding state between the first welding protrusion and the electrode terminal; And welding a second welding protrusion protruding from the lead part and spaced apart from the electrode terminal to the electrode terminal when welding between the first welding protrusion and the electrode terminal is poor.
[29]
In the process of welding the first welding protrusion to the electrode terminal, each of the first welding protrusions protruding from the plurality of lead portions may be welded to the electrode terminals of the plurality of battery cells.
[30]
In the process of welding the first welding protrusion to the electrode terminal, a current is passed between two lead portions extending over the electrode terminal, so that the first welding protrusions respectively formed on the two lead portions are transferred to the electrode terminal. Can be welded.
[31]
The process of checking the welding state of the first welding protrusion and the electrode terminal may include measuring a voltage of the battery cell through the lead part; And determining whether the welding state is defective by comparing the measured voltage with a preset voltage.
[32]
In the process of welding the second welding protrusion to the electrode terminal, welding may be performed by deforming the lead portion so that the second welding protrusion spaced apart from the electrode terminal contacts the electrode terminal.
[33]
In the process of welding the second welding protrusion to the electrode terminal, a current is passed between two lead portions extending over the electrode terminal, so that second welding protrusions respectively formed on the two lead portions are transferred to the electrode terminal. Can be welded.
[34]
Effects of the Invention
[35]
According to the battery cell connection bus bar, the battery pack, and the manufacturing method thereof according to an embodiment of the present invention, in addition to the first welding protrusion for welding to the electrode terminal of the battery cell, an extra second welding protrusion for welding to the electrode terminal By providing, even when a welding failure occurs in the first welding projection, it is possible to stably connect to the electrode terminal through the second welding projection.
[36]
In addition, the second welding protrusion is spaced apart from the electrode terminal of the battery cell when checking the welding state of the first welding protrusion, so that the welding state between the first welding protrusion and the electrode terminal can be checked without error. A guide groove for inducing deformation is formed so that when the first welding protrusion is defective, the second welding protrusion can be easily contacted with the electrode terminal.
[37]
Brief description of the drawing
[38]
1 is a diagram schematically showing a battery pack according to an embodiment of the present invention.
[39]
2 is a view showing a state in which a first welding protrusion of a bus bar for connecting a battery cell according to a first embodiment of the present invention is welded to an electrode terminal of a battery cell.
[40]
3 is a view showing a state in which the second welding protrusion of the bus bar for connecting the battery cell according to the first embodiment of the present invention is welded to the electrode terminal of the battery cell.
[41]
4 is a view showing a state in which a first welding protrusion of a bus bar for connecting a battery cell according to a second embodiment of the present invention is welded to an electrode terminal of a battery cell.
[42]
5 is a view showing a state in which a second welding protrusion of a bus bar for connecting a battery cell according to a second embodiment of the present invention is welded to an electrode terminal of a battery cell.
[43]
6 is a view schematically showing a method of manufacturing a battery pack according to an embodiment of the present invention.
[44]
Mode for carrying out the invention
[45]
Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but will be implemented in a variety of different forms, and only the embodiments of the present invention make the disclosure of the present invention complete, and the scope of the invention to those of ordinary skill in the art. It is provided to fully inform you. In the drawings, the same reference numerals refer to the same elements.
[46]
[47]
1 is a diagram schematically illustrating a battery pack according to an exemplary embodiment of the present invention.
[48]
Referring to FIG. 1, a battery pack according to an embodiment of the present invention includes a plurality of battery cells 100 and a bus bar 200 for electrically connecting the plurality of battery cells 100.
[49]
A plurality of battery cells 100 may be provided to increase the output and capacity of the battery pack. In addition, the battery cell 100 may include a secondary battery cell having a cylindrical shape. In this case, the cylindrical secondary battery cell has a separator interposed between the positive electrode plate with the positive electrode tab and the negative electrode plate with the negative electrode tab, and the electrode assembly in which the positive electrode plate separator and the negative electrode plate are wound in a jelly roll form is a case. It may be provided in a form accommodated inside.
[50]
In such a battery cell 100, an electrode terminal may be formed on one side and an opposite side thereof, a positive terminal may be formed on one side, and a negative terminal may be formed on the other side.
[51]
The plurality of battery cells 100 may be accommodated in the frame 300. Here, the frame 300 may have a plurality of openings corresponding to the shape of the battery cell 100, and the battery cell 100 may be accommodated in the plurality of openings so that the electrode terminals are exposed to the outside. At this time, a plurality of openings may be formed to be arranged in a row direction and a column direction. In the openings arranged in the row direction, the battery cell 100 may be accommodated so that the same electrode terminal, for example, a positive terminal is exposed. The battery cells 100 may be accommodated in the openings arranged in the direction so that electrode terminals having different polarities, for example, a positive terminal and a negative terminal, are exposed to cross each other. That is, a plurality of battery cells 100 accommodated in a plurality of openings may be connected in parallel in a row direction, and battery cells 100 connected in parallel in a row direction may be connected in series with each other.
[52]
The bus bar 200 is a battery cell connection bus bar 200 for electrically connecting a plurality of battery cells 100 to each other, and extends from the body 220 and the body 220 made of a conductive material. Includes a lead portion 210.
[53]
The body 220 may be made of a metal material having high electrical conductivity, and may be formed to extend in a row direction from an upper side or a lower side between an opening arranged in a row direction and an opening arranged in a row direction adjacent thereto. In addition, a plurality of the body portion 220 may be formed to be electrically connected to each other, and may be electrically connected to a positive connection terminal (not shown) and a negative connection terminal (not shown) of the battery pack, respectively. The electrical connection structures between the body parts 220 or between the body part 220 and the positive connection terminal and the negative connection terminal of the battery pack are variously modified and applicable, and the illustration and detailed description thereof will be omitted.
[54]
The lead portion 210 may be formed to extend from the body portion 220 to the electrode terminal of the battery cell 100, and may be provided in plural so as to extend onto the electrode terminals of the plurality of battery cells 100, respectively. .
[55]
Here, at least two of the plurality of lead portions 210 may be formed to extend onto one electrode terminal of the battery cell 100 as shown in FIG. 1. That is, the lead portion 210 may be formed by protruding a welding protrusion as described later. In order to resistance-weld such a welding protrusion to the electrode terminal of the battery cell 100, at least two of the plurality of lead portions 210 The lead portions 210 need to be formed to extend over one electrode terminal of the battery cell 100. In this case, the welding protrusion may be formed on each of the at least two lead portions 210, and a current flows between the at least two lead portions 210 extending over the electrode terminals to form each of the lead portions 210 Each of the welding protrusions can be welded to one electrode terminal of the battery cell 100.
[56]
In the battery pack according to an embodiment of the present invention, the bus bar 200 is formed on the lead portion 210 and formed on the first welding protrusion and the lead portion 210 to be bonded to one electrode terminal of the battery cell 100 And a second welding protrusion disposed to be spaced apart from the one electrode terminal.
[57]
That is, in order to electrically connect the plurality of battery cells 100, the first welding protrusion formed on the lead part 210 is welded to and joined to one electrode terminal of the battery cell 100. Such a first welding protrusion When a welding defect occurs between the first welding protrusion and one electrode terminal of the battery cell 100 during the welding process of, the manufactured battery pack must be disposed of as a whole.
[58]
Accordingly, in the battery pack according to an embodiment of the present invention, the second welding protrusion is formed on the lead part 210 where the first welding protrusion is formed so as to be spaced apart from the electrode terminal of the battery cell 100, so that the first welding protrusion and the battery cell When a welding failure occurs between the electrode terminals of (100), welding can be performed by contacting the second welding protrusion on the electrode terminal. That is, the second welding protrusion serves as a spare in case a welding failure occurs between the first welding protrusion and the electrode terminal of the battery cell 100.
[59]
The battery pack according to an exemplary embodiment of the present invention has an extra second welding protrusion other than the first welding protrusion as described above, so that even when a welding failure occurs between the first welding protrusion and one electrode terminal of the battery cell 100, the battery It is possible to stably electrically connect the plurality of battery cells 100 by welding the electrode terminal in which welding failure has occurred and the second welding protrusion without discarding the pack.
[60]
In this case, the second welding protrusion needs to be disposed so as to be spaced apart from the electrode terminal of the battery cell 100 before determining whether the first welding protrusion is defective. That is, in order to check the welding state of the first welding protrusion and the electrode terminal, the voltage of the battery cell 100 is measured through the lead part 210 on the first welding protrusion, and at this time, the second welding protrusion contacts the electrode terminal. When this occurs, the second welding protrusion and the electrode terminal are electrically connected, so that the welding state of the first welding protrusion and the electrode terminal cannot be confirmed. Accordingly, the second welding protrusion is disposed to be spaced apart from the electrode terminal of the battery cell 100 before determining whether the first welding protrusion is defective.
[61]
In this way, in order to arrange the second welding protrusion to be spaced apart from the electrode terminal on one side of the first welding protrusion, the first welding protrusion and the second welding protrusion are respectively formed to face the electrode terminal, and the second welding protrusion is the It may be formed to protrude lower than the first welding protrusion (first embodiment). In addition, in order to arrange the second welding protrusion to be spaced apart from the electrode terminal on one side of the first welding protrusion, the lead part 210 includes a first lead facing the electrode terminal and a first lead bent from the first lead and disposed. Including 2 leads, the first welding protrusion and the second welding protrusion may be formed on the first lead and the second lead, respectively, to protrude in different directions (second embodiment).
[62]
[63]
Hereinafter, a structure of a bus bar for connecting a battery cell included in a battery pack according to an embodiment of the present invention will be described in more detail. In the description of the bus bar for connecting the battery cells, descriptions overlapping with those described above in relation to the battery pack according to the embodiment of the present invention will be omitted.
[64]
[65]

[66]
2 is a view showing a state in which the first welding protrusion 230 of the bus bar 200 for connecting a battery cell according to the first embodiment of the present invention is welded to the electrode terminal 110 of the battery cell 100, 3 is a view showing a state in which the second welding protrusion 240 of the bus bar 200 for connecting a battery cell according to the first embodiment of the present invention is welded to the electrode terminal 110 of the battery cell 100.
[67]
2 and 3, the bus bar 200 for connecting a battery cell according to the first embodiment of the present invention includes a body portion 220 made of a conductive material, and a lead portion extending from the body portion 220. 210, formed protruding from the lead portion 210, the first welding protrusion 230 for welding to the electrode terminal 110 of the battery cell 100 and the electrode formed protruding from the lead portion 210 A second welding protrusion 240 for welding to the terminal 110 is included, and the second welding protrusion 240 is formed to protrude lower than the first welding protrusion 230.
[68]
The body 220 may be made of a metal material having high electrical conductivity in order to electrically connect the plurality of battery cells 100. The lead portion 210 is formed integrally with the body portion 220 and may be formed to extend from the body portion 220 to the electrode terminal 110 of the battery cell 100, and a plurality of battery cells 100 A plurality of electrodes may be provided so as to respectively extend onto the electrode terminals 110 of the. In addition, as described above, at least two of the plurality of lead portions 210 may be formed to extend onto one electrode terminal 110 of the battery cell 100 for resistance welding.
[69]
The first welding protrusion 230 may protrude from the lead part 210 to be welded to the electrode terminal 110 of the battery cell 100. In addition, the second welding protrusion 240 may be formed to protrude from the lead part 210 to be welded to the electrode terminal 110. At this time, the second welding protrusion 240 may be formed to be spaced apart from one side of the first welding protrusion 230 to face each electrode terminal 110 of the battery cell 100, and the second welding protrusion 240 Is formed to protrude lower than the first welding protrusion 230.
[70]
That is, the first welding protrusion 230 and the second welding protrusion 240 may be formed to protrude from the lead part 210 toward the electrode terminal 110 of the battery cell 100, respectively, and at this time, the first welding protrusion The protrusion height H1 of the protrusion 230 may be formed to be lower than the protrusion height H2 of the second welding protrusion 240. In addition, in the first welding protrusion 230 and the second welding protrusion 240, the upper surface of the lead part 210 is depressed, and the lower surface of the lead part 210 protrudes to be integrally formed with the lead part 210. I can. In this case, the welding protrusion can be easily welded to the electrode terminal 110 by placing a welding rod on the recessed upper surface of the lead part 210 when welding each welding protrusion.
[71]
In this way, by forming the protruding height H1 of the first welding protrusion 230 to be lower than the protruding height H2 of the second welding protrusion 240, the first welding protrusion 230 as shown in FIG. 2 In contact with the electrode terminal 110 of the battery cell 100, the second welding protrusion 240 may be disposed to be spaced apart from the electrode terminal 110. Thereafter, the first welding protrusion 230 is welded to the electrode terminal 110, and in FIG. 2, a state in which the first welding protrusion 230 is melted is not shown, but the first welding protrusion 230 is welded by welding. Of course, a portion of the lower end may be melted and bonded to the electrode terminal 110.
[72]
Here, the second welding protrusion 240 may be formed on the lead part 210 at a position adjacent to the body part 220 than the first welding protrusion 230. That is, the second welding protrusion 240 may be spaced apart from the first welding protrusion 230 located at the end of the lead part 210 toward the body part 220 by a predetermined distance and disposed on the lead part 210. In this way, by arranging the second welding protrusion 240 at a position adjacent to the body part 220 than the first welding protrusion 230, the lead is fixed at both ends by the first welding protrusion 230 and the body part 220 It is possible to easily maintain a state in which the second welding protrusion 240 is separated from the electrode terminal 110 by the tension of the portion 210.
[73]
The welding of the first welding protrusion 230 and the electrode terminal 110 is performed for each of the plurality of battery cells 100. That is, the first welding protrusions 230 protruding from the plurality of lead portions 210 are respectively welded to the electrode terminals 110 of the plurality of battery cells 100. After the first welding protrusion 230 and the electrode terminal 110 are all welded to the plurality of battery cells 100, the first welding protrusion 230 and the electrode terminal 110 of the battery cell 100 are then performed. Each of the welding conditions is checked.
[74]
When it is confirmed that the first welding protrusion 230 and the electrode terminal 110 of the battery cell 100 are normally welded, a conventional residual process for manufacturing a battery pack is performed. However, when it is confirmed that the welding of the first welding protrusion 230 and the electrode terminal 110 of the battery cell 100 is poor, the second welding protrusion 240 is formed of the battery cell 100 as shown in FIG. 3. It is welded to the electrode terminal 110.
[75]
That is, when welding between the first welding protrusion 230 and the electrode terminal 110 of the battery cell 100 is poor, the lead part 210 may be pressed downward on the second welding protrusion 240. In this case, the lead part 210 may be bent between the first welding protrusion 230 and the second welding protrusion 240, whereby the second welding protrusion 240 is formed at the electrode terminal 110 of the battery cell 100. ). In this way, after the second welding protrusion 240 is in contact with the electrode terminal 110 of the battery cell 100, the second welding protrusion 240 is welded to the electrode terminal 110, and in FIG. 3, the second welding protrusion ( Although the appearance of melting of the second welding protrusion 240 is not shown, a part of the lower end of the second welding protrusion 240 may be melted by welding to be bonded to the electrode terminal 110.
[76]
Here, a guide groove may be formed on at least one surface of the lead portion 210 in a direction crossing a direction in which the lead portion 210 extends from the body portion 220. For example, the guide groove may be formed by recessing the upper surface of the lead part 210 to a predetermined depth, as shown in FIGS. 2 and 3, and the guide groove is the lower surface of the lead part 210 or the lead part 210 Of course, it can be formed on both the upper and lower surfaces of ). In addition, the guide groove is a first guide groove 212 positioned between the first welding protrusion 230 and the second welding protrusion 240, and the second welding protrusion 240 2 The guide groove 214 may be included, and at this time, at least one of the first guide groove 212 and the second guide groove 214 may be formed in a plurality.
[77]
2 and 3, two first guide grooves 212 are formed between the first welding protrusion 230 and the second welding protrusion 240, and between the second welding protrusion 240 and the body part 220 In the figure, the two second guide grooves 214 are formed, but the position and number of the first guide groove 212 and the second guide groove 214 are determined by the second welding protrusion when the lead part 210 is pressed. It goes without saying that the 240 may be variously formed in order to easily contact the electrode terminal 110 of the battery cell 100.
[78]
[79]

[80]
4 is a view showing a state in which the first welding protrusion 230 of the bus bar 200 for connecting a battery cell according to the second embodiment of the present invention is welded to the electrode terminal 110 of the battery cell 100, 5 is a view showing a state in which the second welding protrusion 240 of the bus bar 200 for connecting the battery cell according to the second embodiment of the present invention is welded to the electrode terminal 110 of the battery cell 100.
[81]
4 and 5, a bus bar 200 for connecting a battery cell according to a second embodiment of the present invention includes a body 220 made of a conductive material, and a lead portion extending from the body 220. 210, formed protruding from the lead portion 210, the first welding protrusion 230 for welding to the electrode terminal 110 of the battery cell 100 and the electrode formed protruding from the lead portion 210 A second welding protrusion 240 for welding to the terminal 110 is included, and the second welding protrusion 240 is formed to protrude in a direction different from the protruding direction of the first welding protrusion 230.
[82]
As described above, the body 220 may be made of a metal material having high electrical conductivity in order to electrically connect the plurality of battery cells 100. The lead portion 210 is formed integrally with the body portion 220 and may be formed to extend from the body portion 220 to the electrode terminal 110 of the battery cell 100, and a plurality of battery cells 100 A plurality of electrodes may be provided so as to respectively extend onto the electrode terminals 110 of the. In addition, as described above, at least two of the plurality of lead portions 210 may be formed to extend onto one electrode terminal 110 of the battery cell 100 for resistance welding.
[83]
The first welding protrusion 230 may protrude from the lead part 210 to be welded to the electrode terminal 110 of the battery cell 100. In addition, the second welding protrusion 240 may be formed to protrude from the lead part 210 to be welded to the electrode terminal 110. In this case, the second welding protrusion 240 is formed to protrude in a direction different from the protruding direction of the first welding protrusion 230.
[84]
To this end, the lead part 210 includes a first lead 210A facing the electrode terminal 110 of the battery cell 100 and a second lead 210B bent and disposed from the first lead 210A. In addition, the first welding protrusion 230 and the second welding protrusion 240 may be formed on the first lead 210A and the second lead 210B, respectively. In addition, in the first welding protrusion 230 and the second welding protrusion 240, the upper surface of the lead part 210 is depressed, and the lower surface of the lead part 210 protrudes to be integrally formed with the lead part 210. In this case, it is as described above that the welding protrusion can be easily welded to the electrode terminal 110 by placing a welding rod on the recessed upper surface of the lead part 210 when welding each welding protrusion.
[85]
In this way, the first welding protrusion 230 is formed on the first lead 210A facing the electrode terminal 110 of the battery cell 100, and the second welding protrusion 240 is formed from the first lead 210A. For example, by forming on the second lead 210B bent upward and disposed, the first welding protrusion 230 is in contact with the electrode terminal 110 of the battery cell 100, as shown in FIG. 2 The welding protrusion 240 may be disposed to be spaced apart from the electrode terminal 110. Thereafter, the first welding protrusion 230 is welded to the electrode terminal 110, and the state in which the first welding protrusion 230 is melted is not shown in FIG. 4, but the first welding protrusion 230 is welded by welding. Of course, a portion of the lower end may be melted and bonded to the electrode terminal 110.
[86]
In addition, the second welding protrusion 240 may be formed on the lead part 210 at a position adjacent to the body part 220 than the first welding protrusion 230. That is, the second welding protrusion 240 may be spaced apart from the first welding protrusion 230 located at the end of the lead part 210 toward the body part 220 by a predetermined distance and disposed on the lead part 210. In this way, by arranging the second welding protrusion 240 at a position adjacent to the body part 220 than the first welding protrusion 230, the lead at both ends is fixed by the first welding protrusion 230 and the body 220 As described above, the second welding protrusion 240 can be easily maintained in a state separated from the electrode terminal 110 by the tension of the portion 210.
[87]
On the other hand, after the first welding protrusion 230 and the electrode terminal 110 are all welded to the plurality of battery cells 100, the first welding protrusion 230 and the electrode terminal of the battery cell 100 ( 110) will be checked respectively.
[88]
When it is confirmed that the first welding protrusion 230 and the electrode terminal 110 of the battery cell 100 are normally welded, a conventional residual process for manufacturing a battery pack is performed. However, when it is confirmed that the welding of the first welding protrusion 230 and the electrode terminal 110 of the battery cell 100 is poor, the second welding protrusion 240 is formed of the battery cell 100 as shown in FIG. 5. It is welded to the electrode terminal 110.
[89]
That is, when welding between the first welding protrusion 230 and the electrode terminal 110 of the battery cell 100 is poor, the second lead may be pressed downward. At this time, the first lead and the second lead disposed at a predetermined angle may be disposed on the same plane, whereby the second welding protrusion 240 comes into contact with the electrode terminal 110 of the battery cell 100. . In this way, after the second welding protrusion 240 is in contact with the electrode terminal 110 of the battery cell 100, the second welding protrusion 240 is welded to the electrode terminal 110, and in FIG. 5, the second welding protrusion ( Although the appearance of melting of the second welding protrusion 240 is not shown, a part of the lower end of the second welding protrusion 240 may be melted by welding to be bonded to the electrode terminal 110.
[90]
Here, a guide groove may be formed on at least one surface of the lead portion 210 in a direction intersecting the direction in which the lead portion 210 extends from the body portion 220, and the guide groove includes the first welding protrusion 230 and A first guide groove 212 disposed between the second welding protrusions 240 and a second guide groove 214 disposed between the second welding protrusion 240 and the body portion 220 may be included. In addition, as described above, at this time, at least one of the first guide groove 212 and the second guide groove 214 may be formed in a plurality.
[91]
4 and 5, one first guide groove 212 is formed between the first welding protrusion 230 and the second welding protrusion 240, and between the second welding protrusion 240 and the body 220 In the figure, the two second guide grooves 214 are formed, but the position and number of the first guide groove 212 and the second guide groove 214 are determined by the second welding protrusion when the lead part 210 is pressed. It goes without saying that the 240 may be variously formed in order to easily contact the electrode terminal 110 of the battery cell 100.
[92]
[93]
Hereinafter, a method of manufacturing a battery pack according to an embodiment of the present invention will be described in detail. In the description of the method of manufacturing the battery pack, descriptions overlapping with those described above in relation to the bus bar and the battery pack according to an embodiment of the present invention will be omitted.
[94]
6 is a diagram schematically illustrating a method of manufacturing a battery pack according to an embodiment of the present invention.
[95]
Referring to FIG. 6, in the method of manufacturing a battery pack according to an embodiment of the present invention, the first welding protrusion 230 protruding from the lead part 210 is welded to the electrode terminal 110 of the battery cell 100. The process (S100), the process of checking the welding state of the first welding protrusion 230 and the electrode terminal 110 (S200), and the welding of the first welding protrusion 230 and the electrode terminal 110 is poor. In this case, a process (S300) of welding the second welding protrusion 240 formed protruding from the lead part 210 and spaced apart from the electrode terminal 110 to the electrode terminal 110 (S300).
[96]
In the process of welding the first welding protrusion 230 to the electrode terminal 110 of the battery cell 100 (S100), the first welding protrusion 230 protruding from the lead part 210 is removed from the battery cell 100. It is welded to the electrode terminal 110. At this time, the lead portion 210 may be provided on the bus bar 200 and extend from the body portion 220 to the electrode terminal 110 of the battery cell 100, and the lower surface of the lead portion 210 A first welding protrusion 230 and a second welding protrusion 240 are formed to protrude toward the electrode terminal 110. In the process of welding the first welding protrusion 230 to the electrode terminal 110 of the battery cell 100 (S100), the first welding protrusion 230 is in contact with the electrode terminal 110 of the battery cell 100 to be welded. And, the second welding protrusion 240 is disposed to be spaced apart from the electrode terminal 110.
[97]
In the process of welding the first welding protrusion 230 to the electrode terminal 110 of the battery cell 100 (S100), the first welding protrusions 230 protruding from the plurality of lead parts 210 are formed into a plurality of batteries. Each of the electrode terminals 110 of the cell 100 may be welded. In addition, in this case, at least two of the lead portions 210 of the plurality of lead portions 210 may extend onto one electrode terminal 110, in which case the first welding protrusion 230 is an electrode of the battery cell 100 In the process of welding the terminal 110 (S100), a first welding protrusion formed on each of the two lead portions 210 by flowing a current between the two lead portions 210 extending over the electrode terminal 110 It is possible to weld 230 to the electrode terminal 110.
[98]
The process of checking the welding state of the first welding protrusion 230 and the electrode terminal 110 (S200) is whether the welding of the first welding protrusion 230 and the electrode terminal 110 is normal or the first welding protrusion 230 It is checked whether the welding of the and electrode terminals 110 is defective. In this case, the process of checking the welding state of the first welding protrusion 230 and the electrode terminal 110 (S200) is a process of measuring the voltage of the battery cell 100 through the lead part 210 and the measured voltage and It may include a process of determining whether a welding state is defective by comparing a preset voltage.
[99]
The process of measuring the voltage of the battery cell 100 through the lead part 210 may be performed by measuring an open circuit voltage of the battery cell 100 through the lead part 210. In this case, the open-circuit voltage between the lead part 210 in which the first welding protrusion 230 is welded to one electrode terminal 110 of the battery cell 100 and the other electrode terminal of the battery cell 100 may be measured. have.
[100]
The process of determining whether the welding state is defective is to determine whether the welding state is defective by comparing the measured voltage with a preset voltage. That is, when the first welding protrusion 230 is normally welded to the electrode terminal 110 of the battery cell 100, the battery cell 100 exhibits a constant voltage. However, when the first welding protrusion 230 is poorly welded to the electrode terminal 110 of the battery cell 100, the battery cell 100 exhibits a relatively low voltage compared to the normal welding. Accordingly, the voltage when the first welding protrusion 230 is normally welded to the electrode terminal 110 of the battery cell 100 or a voltage having a predetermined difference therefrom is preset as the threshold voltage, and the measured voltage is When the voltage is less than the threshold voltage, it may be determined that the welding state of the first welding protrusion 230 and the electrode terminal 110 is defective.
[101]
Here, when it is confirmed that the first welding protrusion 230 and the electrode terminal 110 of the battery cell 100 are normally welded, a conventional residual process for manufacturing the battery pack is performed (S400). However, when it is confirmed that the welding of the first welding protrusion 230 and the electrode terminal 110 of the battery cell 100 is poor, the process of welding the second welding protrusion 240 to the electrode terminal 110 (S300) is performed. Performed.
[102]
Here, before the process of welding the second welding protrusion 240 to the electrode terminal 110 (S300), the second welding protrusion 240 is disposed to be spaced apart from the electrode terminal 110 of the battery cell 100. Therefore, in the process of welding the second welding protrusion 240 to the electrode terminal 110 (S300), the second welding protrusion 240 disposed to be spaced apart from the electrode terminal 110 of the battery cell 100 is the electrode terminal. The contact between the second welding protrusion 240 and the electrode terminal 110 is made by deforming the lead part 210 as described above.
[103]
That is, in the case of the first embodiment in which the second welding protrusion 240 is formed to protrude lower than the first welding protrusion 230, the lead part 210 is deformed to be bent so that the second welding protrusion 240 is an electrode terminal. In the case of the second embodiment described above, in which the first welding protrusion 230 and the second welding protrusion 240 are formed to protrude in different directions, the lead part 210 is bent. The second welding protrusion 240 and the electrode terminal 110 may be in contact with each other by being deformed to form the same plane.
[104]
Thereafter, in the process of welding the second welding protrusion 240 to the electrode terminal 110 of the battery cell 100 (S300), a current flows between the two lead portions 210 extending over the electrode terminal 110. , It is the same as the case of the first welding protrusion 230 that the second welding protrusions 240 respectively formed on the two lead parts 210 can be welded to the electrode terminal 110 through resistance welding.
[105]
As described above, in addition to the first welding protrusion 230 for welding to the electrode terminal 110 of the battery cell 100, according to the bus bar for connecting the battery cell, the battery pack, and the manufacturing method thereof according to an embodiment of the present invention. The electrode terminal 110 is provided with an extra second welding protrusion 240 for welding to the electrode terminal 110, so that even when a welding failure occurs in the first welding protrusion 230, the electrode terminal 110 ) And can be connected stably.
[106]
In addition, the second welding protrusion 240 is spaced apart from the electrode terminal 110 of the battery cell 100 when checking the welding state of the first welding protrusion 230, and the first welding protrusion 230 and the electrode terminal 110 ) Can be checked without error, and guide grooves 212 and 214 that induce deformation of the lead part 210 are formed on at least one surface of the lead part 210 to weld the first welding protrusion 230 In case of failure, the second welding protrusion 240 can be easily brought into contact with the electrode terminal 110.
[107]
[108]
In the above, preferred embodiments of the present invention have been described and illustrated using specific terms, but such terms are only for clearly describing the present invention, and embodiments of the present invention and terms described are the technical spirit of the following claims And it is obvious that various changes and changes can be made without departing from the scope. Such modified embodiments should not be individually understood from the spirit and scope of the present invention, and should be said to fall within the scope of the claims of the present invention.
[109]
Claims
[Claim 1]
A body made of a conductive material; A lead portion extending from the body portion; A first welding protrusion protruding from the lead part to be welded to the electrode terminal of the battery cell; And a second welding protrusion protruding from the lead part to be welded to the electrode terminal, wherein the second welding protrusion is formed to protrude lower than the first welding protrusion.
[Claim 2]
The bus bar of claim 1, wherein the first welding protrusion and the second welding protrusion are formed to face each of the electrode terminals.
[Claim 3]
A body made of a conductive material; A lead portion extending from the body portion; A first welding protrusion protruding from the lead part to be welded to the electrode terminal of the battery cell; And a second welding protrusion protruding from the lead part to be welded to the electrode terminal, wherein the second welding protrusion is formed to protrude in a direction different from the protruding direction of the first welding protrusion. Bus bar.
[Claim 4]
The method of claim 3, wherein the lead part comprises: a first lead facing the electrode terminal of the battery cell; And a second lead bent and disposed from the first lead, wherein the first welding protrusion and the second welding protrusion are respectively formed on the first lead and the second lead.
[Claim 5]
The bus bar of claim 1 or 3, wherein the second welding protrusion is disposed to be adjacent to the body portion rather than the first welding protrusion.
[Claim 6]
The bus bar of claim 5, wherein a guide groove is formed on at least one surface of the lead portion in a direction crossing an extension direction from the body portion.
[Claim 7]
The method of claim 6, wherein the guide groove comprises: a first guide groove positioned between the first welding protrusion and the second welding protrusion; And a second guide groove positioned between the second welding protrusion and the body portion.
[Claim 8]
The bus bar of claim 7, wherein at least one of the first guide groove and the second guide groove is formed in a plurality.
[Claim 9]
A plurality of battery cells; And a bus bar for electrically connecting the plurality of battery cells, wherein the bus bar includes: a lead portion extending over an electrode terminal of the battery cell; A first welding protrusion formed on the lead portion and bonded to the electrode terminal; And a second welding protrusion formed on the lead portion and disposed to be spaced apart from the electrode terminal.
[Claim 10]
The battery pack of claim 9, wherein the first welding protrusion and the second welding protrusion are formed to face each of the electrode terminals, and the second welding protrusion is formed to protrude lower than the first welding protrusion.
[Claim 11]
The apparatus of claim 9, wherein the lead part comprises: a first lead facing an electrode terminal of the battery cell; And a second lead bent and disposed from the first lead, wherein the first welding protrusion and the second welding protrusion are respectively formed on the first lead and the second lead to protrude in different directions.
[Claim 12]
The battery pack of claim 9, wherein the lead portion is provided in plural, and at least two lead portions of the plurality of lead portions extend onto the electrode terminal.
[Claim 13]
Welding the first welding protrusion protruding from the lead portion to the electrode terminal of the battery cell; Checking a welding state between the first welding protrusion and the electrode terminal; And welding a second welding protrusion protruding from the lead part and spaced apart from the electrode terminal to the electrode terminal when welding between the first welding protrusion and the electrode terminal is poor. .
[Claim 14]
The method of claim 13, wherein the welding of the first welding protrusion to the electrode terminal comprises welding first welding protrusions respectively protruding from a plurality of lead portions to electrode terminals of a plurality of battery cells. .
[Claim 15]
The method of claim 13, wherein the welding of the first welding protrusion to the electrode terminal comprises: a first welding protrusion formed on each of the two lead parts by flowing a current between two lead parts extending over the electrode terminal. Method of manufacturing a battery pack welding to the electrode terminal.
[Claim 16]
The method of claim 13, wherein the checking of the welding state between the first welding protrusion and the electrode terminal comprises: measuring a voltage of the battery cell through the lead part; And comparing the measured voltage with a preset voltage to determine whether the welding state is defective.
[Claim 17]
The method of claim 13, wherein the welding of the second welding protrusion to the electrode terminal comprises: welding the lead by modifying the lead so that a second welding protrusion spaced apart from the electrode terminal contacts the electrode terminal. .
[Claim 18]
The method of claim 13, wherein the welding of the second welding protrusion to the electrode terminal comprises: flowing a current between two lead portions extending over the electrode terminal, and second welding protrusions respectively formed on the two lead portions. Method of manufacturing a battery pack welding to the electrode terminal.