One]Cross-Citation with Related Application(s)
[2]
This application claims the benefit of priority based on Korean Patent Application No. 10-2019-0030176 dated March 15, 2019, and all contents disclosed in the literature of the Korean patent application are incorporated as a part of this specification.
[3]
The present invention relates to a battery module and a method for manufacturing the same, and more particularly, to a battery module having a connection structure of an electrode lead and a bus bar, and a manufacturing method thereof.
background
[4]
Secondary batteries are receiving a lot of attention as an energy source in various product groups such as mobile devices and electric vehicles. Such a secondary battery is a powerful energy resource that can replace the use of conventional products using fossil fuels, and is in the spotlight as an eco-friendly energy source because no by-products are generated due to energy use.
[5]
Recently, as the need for a large-capacity secondary battery structure, including the use of secondary batteries as an energy storage source, increases, the demand for a battery pack having a multi-module structure in which a plurality of secondary batteries are assembled in series/parallel connected battery pack is increasing. .
[6]
On the other hand, when configuring a battery pack by connecting a plurality of battery cells in series/parallel, a battery module composed of at least one battery cell is configured, and other components are added using the at least one battery module to add other components to the battery pack. The general way to configure
[7]
Such a battery module is configured to include a plurality of battery cells stacked together and a bus bar electrically connecting electrode leads of the plurality of battery cells.
[8]
1 is a view showing a state in which an electrode lead in a conventional battery module is connected to a bus bar.
[9]
Referring to FIG. 1 , in the related art, after forming a battery cell stack 40 by stacking battery cells, a battery cell stack 40 and a bus bar frame (not shown) on which the bus bars 20 are mounted are mounted. After assembling, the electrode leads 10 protruding from the battery cell stack were joined to the bus bar 20 mounted on the bus bar frame by laser welding, etc. to bond the electrode leads 10 and the bus bar 20. .
[10]
However, as shown in FIG. 1 , when assembling the battery cell stack 40 with the bus bar 20 , the electrode leads 10 connected to the battery cell stack 40 must be bent to bond with the bus bar. In the bending process, there is a problem that a spring-back phenomenon in which the bending of the previously bent electrode lead is restored to its original state by elasticity may occur.
[11]
Also, as shown in FIG. 1 , when a plurality of electrode leads 10 are bent and joined to the bus bar 20 side by side, the plurality of electrode leads 10 are bent while overlapping to be joined to the bus bar. At this time, a gap occurs between the electrode leads due to a difference in position between the electrode leads 10 due to the interaction of the springback phenomenon occurring between the electrode leads 10 and bending, and the electrode lead 10 and the bus bar 20 . As a difference in welding bonding degree occurs according to a distance between the and, the bonding strength between the electrode lead 10 and the bus bar 20 is lowered, which may cause an abnormality in electrical connectivity.
[12]
In addition, the bending of the electrode lead 10 may have to be performed manually for reasons such as breakage of the lead, which may cause problems such as a decrease in an automated process rate and a decrease in weldability quality.
DETAILED DESCRIPTION OF THE INVENTION
technical challenge
[13]
An object of the present invention is to provide a battery module having a connection structure of a bus bar and an electrode lead capable of improving fairness and reliability of an electrical connection between an electrode lead and the bus bar, and a method of manufacturing the same.
[14]
The problems of the present invention are not limited to the problems mentioned above, and other problems not mentioned will be clearly understood by those skilled in the art from the following description.
means of solving the problem
[15]
A battery module according to an embodiment of the present invention for realizing the above object is a battery cell stack in which a plurality of battery cells are stacked, electrode leads protruding from the battery cell stack, and electrically with the electrode leads a bus bar to be connected and a bus bar frame to which the bus bar is mounted, wherein the bus bar is formed of a clamp part and a fixing part connecting and fixing the clamp part, and the electrode leads are mounted between the clamp parts of the bus bar. do.
[16]
The bus bar frame may include a lower opening corresponding to the fixing part of the bus bar and a locking part corresponding to an end of the tongs of the bus bar.
[17]
The lower opening may correspond to a structure in which the bus bar frame is recessed.
[18]
The tongs of the bus bar may be formed of two clip parts extending from the fixing part, and a distance between the two clip parts may decrease toward the fixing part.
[19]
The electrode leads may be in contact with the clip portion at a portion closer to the fixing portion than to an end of the clip portion.
[20]
The electrode leads may be formed to protrude in a flat plate shape.
[21]
The battery cell stack may further include cell terraces each protruding from adjacent battery cells among the battery cells included in the battery cell stack, and the electrode leads may be formed to protrude from the cell terraces.
[22]
The tongs of the bus bar may be in close contact with the flat surface of the electrode lead in a vertical direction.
[23]
A method of manufacturing a battery module according to an embodiment of the present invention includes the steps of mounting a bus bar in an opening of a bus bar frame, inserting an electrode lead between the tongs of the bus bar, and the bus bar and the electrode lead through a jig It includes the step of adhering and removing the jig.
[24]
In the step of bringing the bus bar and the electrode lead into close contact, the jig may be inserted between the bus bar frame and the bus bar to bring the bus bar and the electrode lead into close contact.
Effects of the Invention
[25]
The battery module according to an embodiment of the present invention inserts and mounts a flat electrode lead to a bus bar, so that the electrode lead and the bus bar can be joined without bending the electrode lead, so that the bonding strength between the electrode lead and the bus bar and the resulting Reliability can be achieved with respect to electrical connections.
[26]
In addition, the battery module according to an embodiment of the present invention can improve the automated process rate according to production as the manual process required for the bending operation is no longer unnecessary.
[27]
In addition, the battery module according to an embodiment of the present invention enables the electrical connection between the electrode lead and the bus bar to be stably made by closely contacting the bus bar and the electrode lead through a jig.
[28]
In addition, in the battery module according to an embodiment of the present invention, the weight of the bus bar can be reduced through a thin clip-shaped bus bar structure.
[29]
Effects of the present invention are not limited to the effects mentioned above, and other effects not mentioned will be clearly understood by those skilled in the art from the description of the claims.
Brief description of the drawing
[30]
1 is a view showing a state in which an electrode lead in a conventional battery module is connected to a bus bar.
[31]
2 is a perspective view showing a battery module according to an embodiment of the present invention.
[32]
3 is a view showing a state in which the electrode lead of FIG. 2 is inserted into the bus bar.
[33]
4 is a cross-sectional view of the bus bar frame of FIG. 3 viewed from the front.
[34]
5 is a cross-sectional view illustrating a state in which a bus bar and an electrode lead are mounted on the bus bar frame of FIG. 4 .
[35]
6 is a cross-sectional view illustrating a state in which a jig is inserted into the bus bar frame of FIG. 5 to closely contact the bus bar and the electrode lead.
Modes for carrying out the invention
[36]
It should be understood that the embodiments described below are illustratively shown to help understanding of the invention, and that the present invention may be implemented with various modifications different from the embodiments described herein. However, in the description of the present invention, if it is determined that a detailed description of a related known function or component may unnecessarily obscure the gist of the present invention, the detailed description and specific illustration thereof will be omitted. In addition, the accompanying drawings are not drawn to scale in order to help understanding of the invention, but dimensions of some components may be exaggerated.
[37]
The first and second terms used in the present application may be used to describe various components, but the components should not be limited by the terms. The terms are used only for the purpose of distinguishing one component from another.
[38]
In addition, the terms used in the present application are only used to describe specific embodiments, and are not intended to limit the scope of rights. The singular expression includes the plural expression unless the context clearly dictates otherwise. In the present application, terms such as "comprises", "consists of" or "consisting It should be understood that this does not preclude the possibility of addition or existence of other features or numbers, steps, operations, components, parts, or combinations thereof.
[39]
Hereinafter, a battery module according to an embodiment of the present invention will be described with reference to FIGS. 2 to 3 .
[40]
2 is a perspective view showing a battery module according to an embodiment of the present invention. 3 is a view showing a state in which the electrode lead of FIG. 2 is inserted into the bus bar.
[41]
2 and 3 , the battery module according to an embodiment of the present invention basically includes a battery cell stack in which a plurality of battery cells 100 are stacked, and battery cells 100 included in the battery cell stack. ), including electrode leads 120 protruding from the electrode lead 120 , a bus bar 200 electrically connected to the electrode lead 120 , and a bus bar frame 300 on which the bus bar 200 is mounted, and additionally stacking battery cells and a frame member 500 surrounding the sieve and the bus bar frame 300 .
[42]
The battery cell 100 is a secondary battery and may be configured as a pouch-type secondary battery. The plurality of battery cells 100 may be stacked to each other so as to be electrically connected to each other to form a battery cell stack.
[43]
Each of the plurality of battery cells 100 may include an electrode assembly, a battery case, and an electrode lead 120 protruding from the electrode assembly. The electrode assembly may include a positive electrode plate, a negative electrode plate, and a separator. The battery case is for packaging the electrode assembly, and may be formed of a laminate sheet including a resin layer and a metal layer. Such a battery case may include a case body and a cell terrace 110 . The electrode lead 120 may be electrically connected to the electrode assembly.
[44]
The configuration of the battery cell 100 described above is an example, and the shape of the battery cell 100 for configuring the battery cell stack may be variously modified.
[45]
The electrode leads 120 may be formed in a flat plate to protrude toward at least one side of the battery cell 100 . These electrode leads 120 may be stacked in one direction and protrude, through which a series or parallel connection between the electrode leads 120 may be possible. The electrode leads 120 may function as battery terminals and may be formed of a metal material such as copper or aluminum. In addition, the electrode lead 120 may be formed in various thicknesses and may be formed in various widths. The thickness or width of the electrode lead 120 may be manufactured differently according to the specifications of the secondary battery and the battery module.
[46]
The bus bar 200 may be electrically connected to the electrode leads 120 by contacting them. For electrical connection with the electrode leads 120 , the bus bar 200 may be formed of an electrically conductive metal material such as copper or aluminum, like the electrode leads 120 .
[47]
Hereinafter, a bus bar frame, a bus bar mounted thereon, and an electrode lead connected to the bus bar in the battery module according to an embodiment of the present invention will be described in detail with reference to FIGS. 2 to 5 .
[48]
4 is a cross-sectional view of the bus bar frame of FIG. 3 viewed from the front. 5 is a cross-sectional view illustrating a state in which a bus bar and an electrode lead are mounted on the bus bar frame of FIG. 4 .
[49]
Referring to FIG. 4 , in the structure of the bus bar frame 300 according to the embodiment of the present invention, an opening 310 is formed by partially opening the upper end of the structure. The opening 310 includes a locking part 311 having a stepped shape with respect to the entrance of the opening 310 at its upper end, and a lower opening 312 recessed further from the center of the opening 310 at its lower end. may include
[50]
Referring to FIG. 5 , the bus bar 200 according to the present embodiment is formed of a clamp part 210 formed to insert the electrode lead 120 , and a fixing part 220 connecting and fixing the clamp part 210 . can be
[51]
The tongs 210 may be formed of two clip parts 211 and 212 respectively extending in an upper diagonal direction from the fixing part 220 . When the electrode lead 120 is inserted, the electrode lead 120 may contact inner surfaces of the two clip parts 211 and 212 .
[52]
The fixing unit 220 may serve to connect and fix the tongs 210 at the lower side of the tongs 210 . The fixing part 220 is connected to the lower ends of the two clip parts 211 and 212, respectively, and according to an embodiment of the present invention, the fixing part 220 is formed to have a curvature downward of the tongs 210, , the electrode lead 120 can facilitate insertion of the tongs 210 and elastically prevent deformation or movement of the tongs 210 so that the tongs 210 are fixed.
[53]
The bus bar 200 as described above may be mounted in the opening 310 formed in the bus bar frame 300 provided on one side of the battery cell stack. At this time, the upper end of the tongs 210 is located at the engaging portion 311 of the bus bar frame 300 , and the fixing unit 220 is located at the lower opening 312 of the bus bar frame 300 .
[54]
The locking parts 311 are respectively recessed at both vertices of the upper side of the opening 310, and the upper ends of the clip parts 211 and 212 on both sides of the tongs 210 are hooked on both locking parts 311, respectively. It may be supported from the upper side so that the bar 200 does not move.
[55]
The lower opening part 312 is formed to correspond to a structure in which the bus bar frame 300 is depressed in the downward direction, and the fixing part 220 is inserted and mounted to support the bus bar 200 from the lower side so that the bus bar 200 does not move. .
[56]
As a result, the bus bar frame 300 may support the tongs 210 of the bus bar 200 at the upper left and right sides, respectively, and support the fixing unit 220 of the bus bar at the lower center.
[57]
According to an embodiment of the present invention, the clamp portion 210 and the fixing portion 220 of the bus bar 200 have a bent plate-shaped clip shape having a minimum width sufficient to be in contact with the flat surface of the electrode lead 120 . is formed to reduce the unnecessary volume of the conventional busbar structure, so that a lighter busbar device can be mounted on the battery module.
[58]
The electrode leads 120 are electrically connected to the bus bar 200 , and for this purpose, contact between the electrode leads 120 and the bus bar 200 is required. According to an embodiment of the present invention, the electrode leads 120 are stacked in a horizontal direction in a flat plate shape to protrude from each of the plurality of battery cells 100 , and the electrode leads 120 protruding in this way are a bus bar. After being inserted into the tongs 210 of 200 , they are contacted and fixed by the left and right clip parts 211 and 212 to establish electrical connection with the bus bar 200 .
[59]
The upper side of the bus bar frame 300 has an open structure, the electrode leads 120 are formed to be easily inserted into the bus bar frame 300 , and the bus bar 200 mounted inside the bus bar frame 300 . Since the clamp part 210 of the upper side is also formed to be open, the electrode leads 120 use the upper open structure of the bus bar frame 300 and the bus bar 200 to form the clamp part 210 of the bus bar 200 . ) and can be easily inserted and mounted.
[60]
The distance between the two clip parts 211 and 212 may decrease toward the lower fixing part 220 based on the distance between the upper both ends of the clip parts 211 and 212 . Accordingly, the electrode leads 120 inserted from the upper side of the bus bar 200 may be inserted downward along the insertion space formed by the two clip parts 211 and 212 of the tongs 210 , and may be inserted toward the lower side. A gap between the two clip parts 211 and 212 may be reduced.
[61]
Accordingly, the electrode leads 120 may contact the portion between the two clip portions 211 and 212 formed closer to the fixing portion 220 than to the upper end of the two clip portions. More specifically, since the flat surfaces of the electrode leads 120 correspond to the opposite surfaces of the two clip parts 211 and 212 , as a result, the tongs 210 of the bus bar 200 are the electrode leads 120 . ) and can be in close contact with the flat surface in the vertical direction.
[62]
According to the embodiment, as the distance between the locking parts 311 positioned at both ends of the upper side of the bus bar frame 300 becomes narrower, the distance between the two clip parts 211 and 212 becomes narrower, so that the electrode leads 120 and the two A contact position between the clip parts 211 and 212 may move upward.
[63]
According to the embodiment of the present invention, in order to continuously enable the contact between the electrode leads 120 and the tongs 210 of the bus bar 200 in a close state, the contact between the two components is joined by welding. can be made with
[64]
As in the embodiment of the present invention, when the electrode leads 120 are formed to protrude in a flat plate shape, and are inserted and mounted between the clip-shaped bus bars made of the clamp and the fixing part, it is necessary to bend the electrode leads 120 . There is no need to increase the automation rate of the process, and since there is no need to worry about the springback phenomenon for bending, the reliability of the electrical connection between the electrode leads and the bus bar can be secured.
[65]
6 is a cross-sectional view illustrating a state in which a jig is inserted into the bus bar frame of FIG. 5 to closely contact the bus bar and the electrode lead.
[66]
Hereinafter, a method of manufacturing a battery module according to an embodiment of the present invention will be described with reference to FIGS. 2 to 6 .
[67]
First, the bus bar 200 is mounted on the opening 310 of the bus bar frame 300 . The tongs 210 of the bus bar 200 are mounted on the engaging parts 311 formed on both sides of the upper opening of the bus bar frame 300 , and the fixing part 220 of the bus bar 200 is the bus bar frame 300 . ) can be mounted on the lower opening of the In this case, the bus bar 200 may be mounted through a jig 400 .
[68]
After the bus bar 200 is mounted on the bus bar frame 300 , the electrode leads 120 are inserted between the tongs 210 of the bus bar 200 . Through this, the electrode leads 120 may be electrically connected to the bus bar 200 from both sides.
[69]
After the electrode lead 120 is inserted between the tongs 210 of the bus bar 200 , the bus bar 200 and the electrode lead 120 are brought into close contact with each other through a jig. As shown in FIG. 6 , the jig may be inserted into the space between the bus bar frame 300 and the bus bar 200 to closely contact the bus bar 200 and the electrode lead 120 . By closely contacting the bus bar 200 and the electrode lead 120 , reliability of the electrical connection between each other can be secured.
[70]
After the bus bar 200 and the electrode lead 120 are brought into close contact with each other through the jig 400 , the jig 400 may be removed from the battery module.
[71]
In the above, preferred embodiments of the present invention have been illustrated and described, but the present invention is not limited to the specific embodiments described above, and it is common in the technical field to which the present invention pertains without departing from the gist of the present invention as claimed in the claims. Various modifications may be made by those having the knowledge of, of course, and these modifications should not be individually understood from the technical spirit or perspective of the present invention.
[72]
Explanation of symbols
[73]
100: battery cell
[74]
110: cell terrace
[75]
120: electrode lead
[76]
200: bus bar
[77]
210: tongs
[78]
211: first clip part
[79]
212: second clip part
[80]
220: fixed part
[81]
300: bus bar frame
[82]
310: opening
[83]
311: catch
[84]
312: lower opening
[85]
400: jig

WE CLAIMS

a battery cell stack in which a plurality of battery cells are stacked; electrode leads protruding from the battery cell stack; a bus bar electrically connected to the electrode leads; and a bus bar frame on which the bus bar is mounted, wherein the bus bar includes a clamp part and a fixing part connecting and fixing the clamp part, the electrode leads are located between the clamp part of the bus bar, The bus bar frame includes an opening, a locking part formed on the upper side of the opening so that the upper end of the tongs is positioned, and a lower opening part formed below the opening so that the fixing part is located.
[Claim 2]
The battery module of claim 1 , wherein the locking part is formed to be stepped on the upper side of the opening, and the upper end of the tongs is hooked to the step of the locking part.
[Claim 3]
The battery module of claim 1 , wherein the lower opening portion is recessed to a lower side of the opening portion, and the fixing portion is inserted and mounted in the lower opening portion.
[Claim 4]
The battery module of claim 1 , wherein the clamp part of the bus bar is formed of two clip parts extending from the fixing part, and the distance between the two clip parts decreases toward the fixing part.
[Claim 5]
The battery module of claim 4, wherein the locking parts are formed on both sides of the opening, respectively, and the upper ends of the two clip parts are respectively hooked to the locking parts formed on the both sides.
[Claim 6]
The battery module of claim 4 , wherein the electrode leads are in contact with the clip portion at a portion closer to the fixing portion than to an end of the clip portion.
[Claim 7]
The battery module of claim 1, wherein the electrode leads are formed to protrude in a flat plate shape.
[Claim 8]
The battery module of claim 7 , further comprising cell terraces each protruding from adjacent battery cells among the battery cells included in the battery cell stack, wherein the electrode leads are formed to protrude from the cell terraces.
[Claim 9]
The battery module of claim 8 , wherein the clamp portion of the bus bar is in close contact with the flat surface of the electrode lead in a vertical direction.
[Claim 10]
mounting the busbar to the opening of the busbar frame; inserting an electrode lead between the tongs of the bus bar; adhering the bus bar to the electrode lead through a jig; and removing the jig.
[Claim 11]
The method of claim 11 , wherein the jig for contacting the bus bar and the electrode lead is inserted between the bus bar frame and the bus bar to closely contact the bus bar and the electrode lead.