Title of Invention: Battery module and manufacturing method thereof
technical field
[One]
Cross-Citation with Related Application(s)
[2]
This application claims the benefit of priority based on Korean Patent Application No. 10-2020-0028574 dated March 06, 2020, 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 for preventing swelling of a battery cell and a method for manufacturing the same.
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 according 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 battery packs 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 including at least one battery cell is configured, and other components are added using the at least one battery module to form a battery pack. The general way to configure
[7]
Such a battery module includes a battery cell stack in which a plurality of battery cells are stacked, and a frame for accommodating the battery cell stack.
[8]
1 is a view showing a battery module including a conventional U-shaped frame.
[9]
Referring to FIG. 1 , the frames covering the conventional battery cell stack 10 are a U-shaped frame 20 covering the lower surface and both sides of the battery cell stack 10 , and the upper surface of the battery cell stack 10 . It is formed of an upper plate 30 that covers the , and an end plate 40 that covers the front and rear surfaces of the battery cell stack 10 . During charging and discharging of the battery cells, a swelling phenomenon in which the battery cells swell may occur. It can receive pressure due to swelling from the laminate. At this time, there is a problem in that only both sides of the U-shaped frame 20 formed in one layer must withstand the swelling pressure of the battery module.
DETAILED DESCRIPTION OF THE INVENTION
technical challenge
[10]
SUMMARY OF THE INVENTION An object of the present invention is to provide a battery module having a frame structure capable of withstanding the swelling of battery cells, and a method for manufacturing the same.
[11]
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
[12]
A battery module according to an embodiment of the present invention for realizing the above object includes: a battery cell stack in which a plurality of battery cells are stacked; a first frame formed of a lower surface and left and right surfaces to cover the lower surface and left and right surfaces of the battery cell stack; The upper surface and the front and rear left and right surfaces are integrally formed to include a second frame that covers the upper surface and the front and rear surfaces of the battery cell stack and the left and right surfaces of the first frame.
[13]
In addition, a method for manufacturing a battery module according to an embodiment of the present invention for realizing the above object includes assembling a battery cell stack on a first frame formed of a lower surface and left and right surfaces; Assembling a second frame integrally formed with an upper surface and front and rear left and right surfaces to cover the upper surface and front and rear surfaces of the battery cell stack and the left and right surfaces of the first frame; and welding the first frame and the second frame.
[14]
The lower left and right sides of the first frame, the lower left and right sides of the second frame, and the front and rear ends of the first frame and the front and rear lower ends of the second frame may be joined by welding.
[15]
Frame surface thicknesses of the first frame and the second frame may be the same.
[16]
Guides are protruded from the lower ends of the left and right surfaces of the first frame, and the guide insertion portions into which the guides are inserted are recessed on the lower left and right sides of the second frame corresponding to the guides, and the guides are inserted into the guide insertion portions. can be
[17]
The left and right surfaces of the first frame and the left and right surfaces of the second frame may be disposed to be perpendicular to the stacking direction of the battery cell stack.
[18]
An upper surface of the second frame may be wider than a lower surface of the first frame.
[19]
The first frame and the second frame may be formed by a press method.
[20]
In the step of welding the first frame and the second frame, the lower left and right sides of the first frame, the lower left and right sides of the second frame, the front and rear ends of the first frame, and the front and rear lower ends of the second frame can be welded.
Effects of the Invention
[21]
The battery module and its manufacturing method according to an embodiment of the present invention provide an effect of preventing swelling without a separate additional structure by adopting a double frame structure in the direction in which the swelling occurs.
[22]
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
[23]
1 is a view showing a battery module including a conventional U-shaped frame.
[24]
2 is an exploded perspective view showing a battery module according to an embodiment of the present invention.
[25]
3 is a view showing a state in which the battery module according to an embodiment of the present invention is assembled.
[26]
4 is a section AA of FIG. 3 , and is a cross-sectional view of a battery module according to an embodiment of the present invention.
[27]
5 is a view showing a battery module according to another embodiment of the present invention.
[28]
6 is a view showing a state in which the battery cell stack according to an embodiment of the present invention is assembled to the first frame.
[29]
FIG. 7 is a view showing a state in which the second frame is assembled to the structure assembled through FIG. 6 .
[30]
8 is a view showing a state in which the first and second frames are coupled by welding the structure assembled through FIG. 7 .
Modes for carrying out the invention
[31]
It should be understood that the embodiments described below are illustratively shown to aid understanding of the invention, and 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 detailed 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.
[32]
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.
[33]
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 this application, terms such as "comprises", "consists of" or "consisting It should be understood that it does not preclude the possibility of addition or existence of further other features or numbers, steps, operations, components, parts, or combinations thereof.
[34]
Hereinafter, a battery module according to embodiments of the present invention will be described with reference to FIGS. 2 to 5 .
[35]
2 is an exploded perspective view showing a battery module according to an embodiment of the present invention. 3 is a view showing a state in which the battery module according to an embodiment of the present invention is assembled. 4 is a section AA of FIG. 3 , and is a cross-sectional view of a battery module according to an embodiment of the present invention. 5 is a view showing a battery module according to another embodiment of the present invention.
[36]
2 to 5 , the battery module according to an embodiment of the present invention is formed of a battery cell stack 100 in which a plurality of battery cells are stacked, a lower surface and left and right surfaces, and the battery cell stack ( 100) The first frame 200 and the upper surface, front and rear left and right surfaces are integrally formed to cover the lower surface and the left and right surfaces of the battery cell stack 100 , and the upper surface and the front and rear surfaces of the battery cell stack 100 and the left and right sides of the first frame 200 . and a second frame 300 covering the surface.
[37]
The battery cell is a secondary battery, and may be configured as a pouch-type secondary battery. The battery cells may be configured in plurality, and the plurality of battery cells may be stacked to each other so as to be electrically connected to each other to form the battery cell stack 100 . Each of the plurality of battery cells may include an electrode assembly, a cell case, and an electrode lead protruding from the electrode assembly.
[38]
According to an embodiment of the present invention, it includes the first and second frames 200 and 300 covering the battery cell stack 100 . The first frame 200 is formed such that the first frame left and right surfaces 210 and the first frame lower surface 220 are integrally formed to cover the lower surface and the left and right surfaces of the battery cell stack 100 .
[39]
The second frame 300, the second frame left and right surfaces 310, the second frame front and rear surfaces 320 and the second frame upper surface 330 are integrally formed, and the upper surface and the front and rear surfaces of the battery cell stack 100 It is formed to cover the surface and the left and right surfaces 210 of the first frame 200 .
[40]
According to an embodiment of the present invention, the second frame upper surface 330 is formed wider than the first frame lower surface 220 so that the second frame left and right surfaces 310 cover the first frame left and right surfaces 210 . can
[41]
Conventionally, since the frame structure formed in the stacking direction of the battery cell stack is formed as a single frame structure, it is difficult to prevent swelling of the battery module when swelling occurs.
[42]
Accordingly, according to an embodiment of the present invention, the dual frame structure of the left and right surfaces 210 of the first frame 200 and the left and right surfaces 310 of the second frame 300 in the stacking direction of the battery cell stack 100 is By forming a reinforced double frame structure in the stacking direction of the battery cells vulnerable to swelling, it is possible to effectively prevent the battery module from swelling when the battery cells are swollen.
[43]
In addition, in the prior art, as a frame for covering the battery cell stack, the structure was structured to cover the battery cell stack by assembling several parts of a U-shaped frame, an upper plate, and two end plates. There is a possibility that the rigidity may be lowered, all parts must be assembled, and the assembly line is long when welding or bolting, and the assembly process is complicated.
[44]
Accordingly, according to an embodiment of the present invention, the battery module structure is formed to cover the battery cell stack 100 only with the two first and second frames 200 and 300 , thereby unifying and simplifying the frame structure, and the end plate can be replaced by the front and rear surfaces 320 of the second frame 300, and the upper surface 330 of the second frame 300 can replace the upper plate, thereby reducing the number of frame parts, and As the assembly process can be reduced, the problem of quality defects that can occur in a complex assembly process can be dramatically improved.
[45]
According to an embodiment of the present invention, the first frame 200 and the second frame 300 may be coupled by welding. In this case, the first and second frames 200 and 300 may be joined by welding the lower ends of the front, rear, left, and right surfaces of the second frame 300 and the first frame 200 . In more detail, the lower left and right surfaces of the first frame 200, the lower left and right surfaces of the second frame 300, the front and rear ends of the first frame 200, and the lower front and rear surfaces of the second frame 300 are welded to each other. can be combined.
[46]
Welding may be performed using a laser, and the first frame 200 and the second frame 300 may be sealed through welding to block electrical connection between the inside and the outside of the battery module. In addition, since the left and right surfaces of the first frame 200 and the left and right surfaces of the second frame 300 are double-coupled, the lower left and right surfaces of the first frame 200 and the lower left and right surfaces of the second frame 300 are welded. It is difficult for the laser beam to enter the battery module, or for foreign substances (spatter) generated during welding to flow into the battery module.
[47]
The thickness of the frame surface of the first frame 200 and the second frame 300 may be the same. The left and right surfaces 210 of the first frame 200 and the left and right surfaces 310 of the second frame 300 may be disposed to be perpendicular to the stacking direction of the battery cell stack 100 .
[48]
5 shows another embodiment of the present invention. According to FIG. 5 , in the battery module according to another embodiment of the present invention, a guide 400 is protruded from the lower left and right sides of the first frame 200 , and a second frame 300 corresponding to the guide 400 . A guide insertion part 500 into which the guide 400 is inserted is formed in the lower left and right sides of the , and the guide 400 may be inserted into the guide insertion part 500 .
[49]
Therefore, when assembling the second frame 300 to the first frame 200 to which the battery cell stack 100 is assembled, the second frame 300 is aligned with the guide 400 formed in the first frame 200 . It can be assembled to one frame 200 . Through assembling through the guide 400 , assembly accuracy may be improved, and assembly rigidity may be strengthened by the protruding guide 400 .
[50]
Hereinafter, a method of assembling a battery module according to an embodiment of the present invention will be described with reference to FIGS. 6 to 8 .
[51]
6 is a view showing a state in which the battery cell stack according to an embodiment of the present invention is assembled to the second frame. FIG. 7 is a view showing a state in which the first frame is assembled to the structure assembled through FIG. 6 . 8 is a view showing a state in which the first and second frames are coupled by welding the structure assembled through FIG. 7 .
[52]
6 to 8 , the method of assembling a battery module according to an embodiment of the present invention includes assembling a battery cell stack 100 on a first frame 200 formed of a lower surface and left and right surfaces ( 6), the step of assembling the second frame 300 in which the upper surface and the front and rear left and right surfaces are integrally formed to cover the upper surface and the front and rear surfaces of the battery cell stack 100 and the left and right surfaces of the first frame 200 ( 7) and welding the first frame 200 and the second frame 300 (FIG. 8).
[53]
According to an embodiment of the present invention, the first frame 200 and the second frame 300 may be formed by a press method. The first and second frames 200 and 300 may be formed of the same material. Through this, it is possible to manufacture the first and second frames 200 and 300 by a single method when manufacturing frame parts, thereby simplifying the manufacturing process and reducing quality defects.
[54]
According to an embodiment of the present invention, in the step of welding the first frame 200 and the second frame 300 , the lower left and right surfaces of the first frame 200 and the lower left and right surfaces of the second frame 300 . And the front and rear ends of the lower surface of the first frame 200 and the front and rear lower ends of the second frame 300 may be welded. The contents of the welding section are shown in FIG. 8 .
[55]
Conventionally, the battery cell stack is inserted into the U-shaped frame, the upper plate is assembled on the upper side of the battery cell stack, the upper plate and the U-shaped frame are welded, the first end plate is assembled, and the first end plate There was a problem in that the frame structure had to be assembled through a complicated assembly process of welding the U-shaped frame and the upper plate with the U-shaped frame and the upper plate, assembling the second end plate, and welding the second end plate, the U-shaped frame and the upper plate.
[56]
However, according to an embodiment of the present invention, since it has a structure that can cover the battery cell stack 100 only with two frame parts of the first and second frames 200 and 300, the battery cell stack 100 is A battery module frame structure through a simple assembly process of inserting into the second frame 300 , assembling the first frame 200 to the second frame 300 , and then welding the first and second frames 200 and 300 to each other can be formed, and as compared to the prior art, the welding process is simplified and the defective rate of the product can be reduced as the manufacturing process is simplified.
[57]
The battery module described above may be included in the battery pack. The battery pack may have a structure in which one or more battery modules according to the present embodiment are collected and packed by adding a battery management system (BMS) that manages the temperature or voltage of the battery and a cooling device.
[58]
The battery pack may be applied to various devices. These devices can be applied to transportation means such as electric bicycles, electric vehicles, hybrid vehicles, etc., but the present invention is not limited thereto and can be applied to various devices that can use a battery module, which also falls within the scope of the present invention. .
[59]
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 are possible 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.
[60]
Explanation of symbols
[61]
100: battery cell stack
[62]
200: first frame
[63]
210: left and right sides of the first frame
[64]
220: when the first frame
[65]
300: second frame
[66]
310: second frame left and right sides
[67]
320: second frame front and rear
[68]
330: second frame upper surface
[69]
400: guide
[70]
500: guide insertion unit
Claims
[Claim 1]
a battery cell stack in which a plurality of battery cells are stacked; a first frame formed of a lower surface and left and right surfaces to cover the lower surface and left and right surfaces of the battery cell stack; and a second frame having an upper surface and front, rear, left and right surfaces integrally formed to cover the upper surface and front and rear surfaces of the battery cell stack and the left and right surfaces of the first frame.
[Claim 2]
The battery module of claim 1, wherein the lower left and right sides of the first frame and the lower left and right sides of the second frame and the front and rear ends of the first frame and the front and rear lower ends of the second frame are welded together.
[Claim 3]
The battery module of claim 1 , wherein the frame surface thickness of the first frame and the second frame is the same.
[Claim 4]
[Claim 2] The method of claim 1, wherein guides are protruded from the lower ends of the left and right surfaces of the first frame, and the guide insertion parts into which the guides are inserted are recessed on the lower ends of the left and right surfaces of the second frame corresponding to the guides, and the guides are A battery module inserted into the guide insertion part.
[Claim 5]
The battery module of claim 1 , wherein left and right surfaces of the first frame and left and right surfaces of the second frame are perpendicular to a stacking direction of the battery cell stack.
[Claim 6]
The battery module of claim 1, wherein an upper surface of the second frame is wider than a lower surface of the first frame.
[Claim 7]
Assembling a battery cell stack on a first frame formed of a lower surface and left and right surfaces; Assembling a second frame integrally formed with an upper surface and front and rear left and right surfaces to cover the upper surface and front and rear surfaces of the battery cell stack and the left and right surfaces of the first frame; and welding the first frame and the second frame to each other.
[Claim 8]
The method of claim 7 , wherein the first frame and the second frame are formed by a press method.
[Claim 9]
[8] The method of claim 7, wherein in the welding-combining of the first frame and the second frame, the lower left and right surfaces of the first frame, the lower left and right surfaces of the second frame, the front and rear ends of the lower surface of the first frame, and the second frame A method of manufacturing a battery module by welding the front and rear lower ends of the frame.
[Claim 10]
A battery pack comprising the battery module according to claim 1 .