Technology field
[One]
The present invention relates to a unit module having a busbar frame structure capable of facilitating welding and a battery module including the same, and more specifically, a bus to facilitate welding between electrode leads and busbars. It relates to a unit module having a structure provided with a welding slit in the bar frame and a battery module including the same.
[2]
This application is a priority claim application for Korean Patent Application No. 10-2018-0045710 filed on April 19, 2018, and all contents disclosed in the specification and drawings of the application are incorporated in this application by citation.
Background
[3]
In a battery module in which a plurality of battery cells are connected, the electrical connection between the battery cells is usually made by welding and attaching the electrode leads of each of the battery cells to be electrically connected to each other to one bus bar.
[4]
In the case of laser welding, which is one of the methods of connecting the electrode lead and the bus bar, the electrode lead is pressed toward the bus bar by using a welding jig that can closely connect the electrode lead and the bus bar of the battery cell to improve welding quality. It is done in
[5]
1, a conventional battery module is shown. As in the conventional battery module shown in FIG. 1, after pressing the electrode lead and the bus bar using a welding jig for welding, that is, pressing the electrode lead 1 with the contact jig, the bus bar disposed under the electrode lead 1 (2) In the case of a model that needs to be welded after being in close contact with each other, a close contact jig having a size and shape suitable for the corresponding model is required.
[6]
This means that the close contact jig for close contact between the electrode lead and the bus bar must be made with different close contact jigs for each battery module of different size/type.
[7]
In addition, in the case of a model in which the electrode lead and the busbar are to be welded using the welding jig for welding, space/structural constraints that a minimum space for seating the jig should be secured on the main surface of the welding part for the purpose of applying the welding jig when performing welding You will follow too.
[8]
Accordingly, there is a need to develop a battery module structure that can easily perform welding without such space/structural constraints and without having to provide different welding jigs for each battery module model.
Detailed description of the invention
Technical challenges
[9]
The present invention has been devised in consideration of the above-described problems, so that the busbar frame itself can serve as a welding jig, without the need to provide a dedicated welding jig for each model even in the case of different battery module models. The aim is to make welding easy.
[10]
However, the technical problem to be solved by the present invention is not limited to the above-described problems, and other problems that are not mentioned will be clearly understood by those skilled in the art from the description of the invention described below.
Task resolution
[11]
The unit module according to an embodiment of the present invention for solving the above-described problem includes an electrode assembly, a cell case accommodating the electrode assembly, and an electrode lead connected to the electrode assembly and drawn out of the cell case Battery cells; A bus bar attached to the electrode lead; And attached to the terrace portion of the battery cell to accommodate at least a portion of the electrode lead and the bus bar therein, pressurizing the electrode lead and the bus bar so as to be in close contact between the electrode lead and the bus bar. It is formed at a position corresponding to the electrode lead, the bus bar frame having a welding slit to expose the contact portion of the bus bar and the electrode lead to the outside.
[12]
The bus bar is in parallel with the electrode lead, is in contact with the electrode lead, a junction located inside the bus bar frame; And an exposed portion that is bent from the junction portion and vertically disposed with the junction portion, and is drawn out of the bus bar frame. And a hook portion extending in a direction parallel to the exposed portion from an end portion of the junction portion.
[13]
The bus bar frame includes a hook receiving groove extending from the welding slit; And a hook fixing portion formed on an inner wall surface of the hook receiving groove.
[14]
The busbar frame may have a busbar seating surface formed in a concave shape on the outer surface of the busbar frame so as to have a size and shape corresponding to the exposed portion of the busbar so that the exposed portion can be seated.
[15]
The bus bar frame may be provided with a damage preventing groove formed at a certain depth on the seating surface so that the bus bar and the bus bar frame are partially uncontacted to prevent damage to the bus bar frame due to heat caused by welding.
[16]
The bus bar frame may include a first unit frame covering at least a portion of an upper surface of the terrace portion; And a second unit frame covering at least a portion of the lower surface of the terrace unit and coupled to the first unit frame.
[17]
In the bus bar frame, the shapes of the first unit frame and the second unit frame may be point-symmetrical to each other.
[18]
A battery module according to an embodiment of the present invention includes: a unit module stack in which a plurality of unit modules according to an embodiment of the present invention are connected; And a connector connecting between the bus bars of the unit modules adjacent to each other.
[19]
On the other hand, the battery pack according to an embodiment of the present invention is implemented in a form including a plurality of battery modules according to an embodiment of the present invention described above, the vehicle according to an embodiment of the present invention, the present invention It is implemented in a form including a battery pack according to an embodiment.
Effects of the Invention
[20]
According to an aspect of the present invention, by allowing the busbar frame itself to serve as a welding jig, welding can be easily performed without the need to provide a dedicated welding jig for each model even in the case of different battery module models. have.
Brief description of drawings
[21]
The following drawings attached to the present specification illustrate preferred embodiments of the present invention, and the present invention serves to further understand the technical idea of ​​the present invention together with the detailed description of the invention described below. It should not be interpreted as being limited to.
[22]
1 is a view showing a conventional battery module structure.
[23]
2 is a perspective view showing a part of a battery module according to an embodiment of the present invention.
[24]
3 is a front view showing a part of a battery module according to an embodiment of the present invention.
[25]
4 is a view showing a unit module stack applied to a battery module according to an embodiment of the present invention.
[26]
5 is an exploded perspective view showing a unit module applied to a battery module according to an embodiment of the present invention.
[27]
6 is a perspective view showing a battery cell applied to a battery module according to an embodiment of the present invention.
[28]
7 is a front view showing a unit module and a bus bar coupled to a battery module according to an embodiment of the present invention.
[29]
8 and 9 are perspective views illustrating unit frames constituting a bus bar frame applied to a battery module according to an embodiment of the present invention, from different angles.
[30]
10 is a side view showing a unit frame constituting a bus bar frame applied to a battery module according to an embodiment of the present invention.
Mode for carrying out the invention
[31]
Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. Prior to this, the terms or words used in the present specification and claims should not be interpreted as being limited to ordinary or dictionary meanings, and the inventor appropriately explains the concept of terms in order to explain his or her invention in the best way. Based on the principle that it can be defined, it should be interpreted as meanings and concepts consistent with the technical spirit of the present invention. Therefore, the embodiments shown in the embodiments and the drawings shown in the present specification are only some of the most preferred embodiments of the present invention and do not represent all of the technical spirit of the present invention, and thus can replace them at the time of application. It should be understood that there may be equivalents and variations.
[32]
[33]
First, the overall configuration of the battery module according to an embodiment of the present invention will be described with reference to FIGS. 2 to 5.
[34]
2 is a perspective view showing a part of a battery module according to an embodiment of the present invention, and FIG. 3 is a front view showing a part of a battery module according to an embodiment of the present invention. In addition, Figure 4 is a view showing a unit module stack applied to a battery module according to an embodiment of the present invention, Figure 5 is an exploded perspective view showing a unit module applied to a battery module according to an embodiment of the present invention .
[35]
2 and 3, a battery module according to an embodiment of the present invention is implemented in a form including a unit module stack 10, a connector 20, and an external terminal 30.
[36]
Referring to FIGS. 4 and 5, the unit module stack 10 is a stack formed by stacking a plurality of unit modules 100, and each unit module 100 includes a battery cell 110. , It is implemented in a form including a bus bar 120 connected to the electrode lead 114 of the battery cell 110 and a bus bar frame 130 attached to the terrace portion T of the battery cell 110. Each unit module stack 10 is stacked so that the wide surfaces of the battery cells 110 adjacent to each other face each other to form one unit module stack 10.
[37]
The connector 20 is a component applied to electrically connect the unit module stacks 10 adjacent to each other, and connects between the bus bars 130 provided in the unit module stacks 10 adjacent to each other. do.
[38]
The external terminal 30 is in contact with the bus bar 130 provided in the unit module 100 disposed on the outermost of the plurality of unit modules 100 constituting the unit module stack 10, which is external It functions as a terminal for electrical connection with electronic devices.
[39]
[40]
Next, a battery cell 110 constituting the unit module 100 according to an embodiment of the present invention will be described in detail with reference to FIG. 6 together with FIG. 5.
[41]
5 is an exploded perspective view showing a unit module applied to a battery module according to an embodiment of the present invention, and FIG. 6 is a perspective view showing a battery cell applied to a battery module according to an embodiment of the present invention.
[42]
5 and 6, a pouch type battery cell may be applied to the battery cell 110. The battery cell 110 may be implemented in a form including an electrode assembly (not shown), a cell case 111 and an electrode lead 114.
[43]
Although not shown in the drawing, the electrode assembly has a form in which a separator is interposed between the positive and negative plates alternately repeatedly stacked, and it is preferable that the separators are positioned at the outermost sides of each side for insulation.
[44]
The positive electrode plate is made of a positive electrode current collector and a positive electrode active material layer coated on one or both sides thereof, and a positive electrode non-coated region where a positive electrode active material is not coated is formed at one end, which is an electrode lead. It functions as a positive electrode tab connected to 114.
[45]
Similarly, the negative electrode plate is made of a negative electrode current collector and a negative electrode active material layer coated on one or both sides thereof, and a negative electrode non-coated region where the negative electrode active material layer is not coated is formed at one end thereof. The region functions as a negative electrode tab connected to the electrode lead 114.
[46]
In addition, the separator is interposed between the positive electrode plate and the negative electrode plate to prevent direct contact between electrode plates having different polarities, but may be made of a porous material to enable ionic movement by using an electrolyte between the positive electrode plate and the negative electrode plate as a medium. have.
[47]
The cell case 111 extends in the circumferential direction of the receiving part 112 accommodating the electrode assembly (not shown) and the accommodating part, and the electrode lead 114 is thermally fused to the outside to open the cell case 111. The sealing portion 113 to be sealed includes two regions.
[48]
The electrode lead 114 is divided into a positive electrode lead connected to the positive electrode tab and a negative electrode lead connected to the negative electrode tab, and each of the positive electrode lead and the negative electrode lead is withdrawn to the outside of the cell case 111, and withdrawn in opposite directions to each other. do.
[49]
On the other hand, in the present invention, in the sealing portion 113 formed around the receiving portion 112, the sealing portion 113 located in the direction in which the electrode lead 114 is drawn out is particularly called the terrace portion (T). Let's define.
[50]
[51]
Next, the bus bar 120 constituting the unit module 100 according to an embodiment of the present invention will be described in detail with reference to FIG. 5 referred to above.
[52]
Referring to FIG. 5, the bus bar 120 is bonded to the electrode lead 114 by welding while being fixed to the bus bar frame 130, and some are located inside the bus bar frame 130 and the rest Some are exposed outside of the busbar frame 140. As such, a portion of the busbar frame 140 exposed to the outside of the busbar frame 140 is connected to the above-described connector 20 (see FIGS. 2 and 3), whereby the electrical between the battery unit modules 100 adjacent to each other The connection is made.
[53]
More specifically, the bus bar 120 includes a junction portion 121, an exposed portion 122 and a hook portion 123.
[54]
The bonding part 121 extends in a direction parallel to the electrode lead 114, that is, extends in a horizontal direction to contact the electrode lead 114, and is located inside the bus bar frame 130. The exposed portion 122 is bent from the junction portion 121 and extends in a direction perpendicular to the junction portion 121 and is drawn out of the bus bar frame 130 and seated on the bus bar seating portion 136 to be described later. do.
[55]
The hook portion 123 extends in a direction parallel to the exposed portion 122 from the end of the bonding portion 121, and is provided with one or two or more. The hook portion 123 is to allow the bus bar 120 to be fixed to the inside of the bus bar frame 130, and is coupled to the hook fixing portion 135 provided on the inner surface of the bus bar frame 130. / Fixed.
[56]
As described above, the bus bar 120 is fixedly installed inside the bus bar frame 120, and a part of the bus bar 120 is installed to be exposed to the outside of the bus bar frame 120 and is located inside the bus bar frame 120. The bonding part 121, which is a part to be connected, is joined to the lower surface of the electrode lead 114, and the exposed part 122, which is a part located outside the bus bar frame 120, is connected to the connector 20 and adjacent unit modules ( 100) Let each other be electrically connected.
[57]
[58]
Next, the bus bar frame 130 constituting the unit module 100 according to an embodiment of the present invention will be described in detail with reference to FIGS. 7 to 10 together with FIG. 5 referred to above.
[59]
7 is a front view showing a unit module and a bus bar coupled to a battery module according to an embodiment of the present invention, and FIGS. 8 and 9 are bus bars applied to a battery module according to an embodiment of the present invention It is a perspective view showing a unit frame constituting the frame from different angles, Figure 10 is a side view showing a unit frame constituting the bus bar frame applied to the battery module according to an embodiment of the present invention.
[60]
First, referring to FIGS. 5 and 7, the bus bar frame 130 is attached to the terrace portion T of the battery cell 110 and functions as a support of the bus bar 120 as described above.
[61]
The bus bar frame 130 is implemented by combining the first unit frame 130A and the second unit frame 130B having the same shape. That is, the first unit frame 130A and the second unit frame 130B are parts having the same shape as each other, and the first unit frame 130A covers at least a portion of the upper surface of the terrace portion T, and the second The unit frames 130A are coupled to each other while covering at least a portion of the lower surface of the terrace portion T.
[62]
Meanwhile, when the first unit frame 130A and the second unit frame 130B are combined to form one bus bar frame 130, the first unit frame 130A and the second unit frame 130B ) Is in a point-symmetry relationship.
[63]
That is, in the completed one bus bar frame 130, if the first unit frame 130A is rotated 180 degrees based on the center point in the longitudinal direction, the second unit frame 130B has the same shape.
[64]
As described above, when a pair of unit frames 130A and 130B having a point-symmetry relationship with each other is coupled, the bus bar 130 is drawn out through a gap of the bonding surface. That is, the exposed portion 122 of the bus bar 120 is drawn out through a gap between the engaging surfaces of the first unit frame 130A and the second unit frame 130B.
[65]
In addition, the withdrawn bus bar 130 is bent toward either one of the first unit frame 130A or the second unit frame 130B and is formed in the first unit frame 130A or the second unit frame 130B. Seated on the bus bar seating portion 136, the bending direction is to establish an electrical connection with any one of the unit module contacting the first unit frame (130A) and the unit module 100 and the second unit frame (130B) It depends on whether it is.
[66]
[67]
As described above, since the pair of unit frames 130A and 130B are parts having the same shape with each other, referring to FIGS. 8 to 10 in describing a specific structure of the bus bar frame 130, one unit frame It will be described based on (130A or 130B).
[68]
8 to 10, the unit frames 130A and 130B are fixed protrusions 131, protrusion receiving grooves 132, welding slits 133, hook receiving grooves 134, and hook fixing parts 135. , It may be implemented in a form including a bus bar seating portion 136, a connector holder (137).
[69]
The fixing protrusion 131 and the protrusion receiving groove 132 are formed on at least one or more on the engagement surface of each of the unit frames 130A and 130B, and the fixing protrusion 131 and the protrusion receiving groove 132 are unit frames (130A, 130B) are formed in pairs at corresponding positions of each opposing surface. That is, the fixing protrusion 131 formed on the engaging surface of the first unit frame 130A is formed at a position corresponding to the size and shape corresponding to the projection receiving groove 132 formed on the engaging surface of the second unit frame 130B. Likewise, the protrusion receiving groove 132 formed on the engaging surface of the first unit frame 130A is at a position corresponding to the size and shape corresponding to the fixed protrusion 131 formed on the engaging surface of the second unit frame 130B. Is formed.
[70]
The first unit frame 130A and the second unit frame 130B may be coupled/fixed to each other due to the formation of the mating fixing protrusions 131 and the protrusion receiving grooves 132 as described above.
[71]
[72]
8 and 10, the welding slit 133 is formed on a surface perpendicular to a bonding surface of the unit frames 130A and 130B, and an electrode lead 114 positioned inside the busbar frame 130. (See FIG. 5) and to be able to perform welding on the joint of the bus bar 120. The welding slit 133, the width of the bonding portion of the electrode lead 114 and the bus bar 130, so that welding can be made over the entire width of the bonding portion of the electrode lead 114 and the bus bar 130 It can be formed to a corresponding length.
[73]
The bus bar frame 130 is attached to the battery cell 110 and constitutes the unit module 100, and the bus bar 120 fixed/combined therein is pressed against the electrode lead 114. It can also perform the function as a pressing jig, and also, by providing the welding slit 133, it is possible to easily perform the welding without a separate operation for securing a space for welding.
[74]
The hook receiving groove 134 is formed to extend from the welding slit 133 to provide a space in which the hook portion 123 of the bus bar 130 can be accommodated. In consideration of this function, the hook receiving groove 134 may be formed in the same number as the hook portion 123.
[75]
The hook fixing portion 135 is formed on the inner wall surface of the hook receiving groove 134, and has a shape corresponding to the fastening with the hook portion 134. That is, the hook fixing part 135 may be formed in various forms, such as a shape of a groove formed on the hook receiving groove 134 or a shape of a protruding protrusion.
[76]
The bus bar seating portion 136 corresponds to the exposed portion 132 so that the exposed portion 132, which is a portion exposed to the outside of the bus bar frame 130 among the bus bars 120, can be seated without shaking. It is formed concavely on the outer surface of the busbar frame 130 in size and shape.
[77]
The bus bar seating portion 136 may be provided with a damage preventing groove 136a formed in a concave groove shape along the longitudinal direction on the surface thereof, which is a bus bar 130 and a connector 20 (FIGS. 2 and 3 ). This is to prevent damage to the busbar seating portion 136 in the process of welding performed for coupling.
[78]
That is, the bus bar frame 130 may be made of a resin injection material. In this case, welding is performed for coupling the exposed portion 132 of the bus bar 120 seated on the seating portion 136 and the connector 20. In the course of being performed, it is highly likely that the busbar seating portion 136 is damaged by heat.
[79]
Accordingly, a groove is formed at a position corresponding to a welding line where welding is performed to partially prevent the busbar 130 and the busbar seating portion 136 from contacting each other, thereby preventing the resin injection material from melting due to heat conduction by welding. Is to do.
[80]
[81]
Next, the connector holder 137 will be described in detail with reference to FIGS. 7 to 11 together with FIGS. 2 and 3.
[82]
The connector holder 137 is formed in a protruding form on the same surface as the busbar seating portion 136 of the unit frames 130A, 130B, and one side and/or the other side in the longitudinal direction of the unit frames 130A, 130B. At least one is formed.
[83]
The connector holder 137 is a component applied to fix the connector 20 in performing welding for joining the connector 20 and the bus bar 120.
[84]
2 and 3, the connector holders 137 provided in each of the pair of unit modules 100A and 100B adjacent to each other are simultaneously engaged with one connector 20, and thus the first bent toward each other. The bus bar 120 of the unit module 100A and the bus bar 120 of the second unit module 100B are in common contact with one connector 20 so that a pair of unit modules 100A, 100B are electrically connected. Leads to
[85]
[86]
Although the present invention has been described above by way of limited examples and drawings, the present invention is not limited by this and will be described below and the technical thoughts of the present invention by those skilled in the art to which the present invention pertains. Of course, various modifications and variations are possible within the equal scope of the claims.

Claim
[Claim 1]
A battery cell including an electrode assembly, a cell case accommodating the electrode assembly, and an electrode lead connected to the electrode assembly and drawn out of the cell case; A bus bar attached to the electrode lead; And attached to the terrace portion of the battery cell to accommodate at least a portion of the electrode lead and the bus bar therein, pressurizing the electrode lead and the bus bar so as to be in close contact between the electrode lead and the bus bar. A bus bar frame formed at a position corresponding to the electrode lead and having a welding slit to expose the contact portion between the bus bar and the electrode lead to the outside; Unit module comprising a.
[Claim 2]
According to claim 1, The bus bar, It is extended in a direction parallel to the electrode lead is in contact with the electrode lead, a junction located inside the bus bar frame; And an exposed portion that is bent from the junction portion and extends in a direction perpendicular to the junction portion, and is drawn out of the bus bar frame. And a hook portion extending in a direction parallel to the exposed portion from an end portion of the bonding portion. Unit module characterized in that it comprises a.
[Claim 3]
According to claim 2, The bus bar frame, Hook receiving groove formed extending from the welding slit; And a hook fixing portion formed on an inner wall surface of the hook receiving groove. Unit module characterized in that it comprises a.
[Claim 4]
The bus bar seating of claim 2, wherein the bus bar frame has a size and shape corresponding to an exposed portion of the bus bar, and is formed concavely with a step on the outer surface of the bus bar frame so that the exposed portion can be seated. Unit module characterized in that it has a portion.
[Claim 5]
According to claim 4, The bus bar frame is formed at a predetermined depth on the seating surface to prevent the busbar and the busbar frame from partially contacting the damage prevention groove to prevent damage to the busbar frame due to heat caused by welding. Unit module characterized in that it comprises a.
[Claim 6]
According to claim 1, The bus bar frame, A first unit frame covering at least a portion of the upper surface of the terrace portion; And a second unit frame covering at least a portion of the lower surface of the terrace unit and coupled to the first unit frame. Unit module characterized in that it comprises a.
[Claim 7]
The unit module according to claim 6, wherein in the busbar frame, the first unit frame and the second unit frame have a point-symmetrical relationship with each other.
[Claim 8]
A unit module stack in which a plurality of unit modules according to any one of claims 1 to 7 are connected; And a connector connecting the bus bars of the unit modules adjacent to each other. Battery module comprising a.
[Claim 9]
A battery pack implemented by connecting a plurality of battery modules according to claim 8.
[Claim 10]
A vehicle comprising the battery pack according to claim 9.