Battery module and method for manufacturing a battery module

Abstract

According to an embodiment of the present invention, due to the structural characteristics of the insulating part, by ensuring a greater insulation distance between the cell assembly and the frame, it is possible to prevent a decrease in function due to electrical phenomena and prevent damage to the cell assembly caused by the spatter phenomenon that occurs during the welding process of the frame, thereby increasing the yield of the battery module.

Description

Technical Field

[0001] This application claims the benefit of priority based on Korean Patent Application No. 10-2022-0065688 filed on May 27, 2022 and Korean Patent Application No. 10-2023-0062576 filed on May 15, 2023, and all the contents disclosed in the documents of the Korean patent applications are incorporated herein by reference in their entirety.

[0002] The present invention relates to a battery module and a method of manufacturing the same.

Background Art

[0003] Generally, types of secondary batteries include nickel-cadmium batteries, nickel-metal hydride batteries, lithium-ion batteries, and lithium-ion polymer batteries. Such secondary batteries are used not only in small products such as digital cameras, P-DVDs, MP3Ps, mobile phones, PDAs, portable game devices, power tools, and e-bikes, but also in large products that require high power such as electric vehicles and hybrid vehicles, as well as power storage devices for storing surplus generated power and new / renewable energy, and backup power storage devices.

[0004] To manufacture such secondary batteries, first, an electrode active material slurry is applied to a positive electrode current collector and a negative electrode current collector to manufacture a positive electrode and a negative electrode, and these are laminated on both sides of a separator to form an electrode assembly having a predetermined shape. Also, the electrode assembly is housed in a battery case, an electrolyte is injected, and then sealed.

[0005] A cell assembly can be manufactured by housing a plurality of electrode assemblies in a pack, and a battery module can be manufactured by housing the cell assembly in a frame. When the cell assembly is disposed inside the frame, there is a problem that the performance of the battery deteriorates due to electrical phenomena between the frame and the cell assembly. To prevent this, a method of attaching an insulating sheet to the inner surface of the frame to secure an insulating distance between the frame and the cell assembly is utilized. Therefore, in the process of manufacturing a battery module, there is an increasing need to devise the arrangement and structure of the insulating sheet in order to more effectively secure the insulating distance between the frame and the cell assembly.

[0006] In addition, in the process of welding the upper surface of the frame with the cell assembly located inside, there may be a problem that the cell assembly is damaged due to the flame from welding scattering. In this regard, there is a situation where a battery module having a structure for preventing damage by welding spatter is required.

SUMMARY OF THE INVENTION

PROBLEMS TO BE SOLVED BY THE INVENTION

[0007] One problem to be solved by the present invention is to provide a battery module that further secures an insulating distance between a cell assembly and a frame.

[0008] One problem to be solved by the present invention is to provide a battery module that prevents a cell assembly from being damaged by a spatter phenomenon occurring during the welding process of a frame.

MEANS FOR SOLVING THE PROBLEMS

[0009] A battery module according to an embodiment of the present invention includes a cell assembly, a frame that forms an accommodation space inside to accommodate the cell assembly, and an insulating portion disposed inside a first surface that is a side surface of the frame, the insulating portion being located between the frame and the cell assembly and having a shape bent toward the cell assembly.

[0010] The insulating portion may include a side member connected to the inside of the first surface, and a bent member connected to one end of the side member and having a shape bent toward the cell assembly.

[0011] The frame may include a main body that forms an accommodation space with a front surface and a rear surface that are open in the front and rear directions with respect to the longitudinal direction, and a second surface that is a plane parallel to the longitudinal direction being open, an end plate that covers the front surface and the rear surface and is connected to the main body, and a cover plate that covers the second surface and is connected to the main body.

[0012] The first surface, which is different from the second surface, is formed on the main body parallel to the longitudinal direction of the main body, and the bent member can protrude from the side member and be bent toward the cell assembly.

[0013] The bent member can be positioned between the cell assembly and the second surface.

[0014] The bent member can protrude from the side member perpendicular to the longitudinal direction of the main body.

[0015] The cell assembly can be spaced apart from the front surface and the rear surface by a predetermined distance, and a part of the side member can be disposed in the space between the cell assembly and the front surface and the rear surface.

[0016] In a state where the cell assembly is placed in the accommodation space, the distance between the cell assembly and the second surface can be shorter than the distance between the cell assembly and the front surface and the rear surface.

[0017] The insulating portion may further include an annular member connected to the other end of the bent member and having a shape bent in a direction opposite to the direction in which the bent member is bent.

[0018] A method of manufacturing a battery module by positioning a cell assembly in a housing space with respect to a frame that forms a first surface and an open second surface and includes a cover plate connected to the second surface to form an inner housing space, the method of manufacturing a battery module according to an embodiment of the present invention comprising: an arranging step of arranging an insulating portion including a side member connected to the inside of the first surface and a bent member protruding from the side member and having a shape bent toward the cell assembly; a placing step of moving the cell assembly through the second surface and placing it in the housing space; and a welding step of covering the second surface with the cover plate and welding it to the main body.

Effects of the Invention

[0019] According to a preferred embodiment of the present invention, by ensuring a greater insulation distance between the cell assembly and the frame, it is possible to prevent a decrease in function due to electrical phenomena.

[0020] According to a preferred embodiment of the present invention, by preventing the cell assembly from being damaged by spatter generated during the welding process of the frame, the yield of the battery module can be increased.

[0021] In addition, it can include effects that can be easily predicted by those skilled in the art from the configuration according to a preferred embodiment of the present invention.

Brief Description of the Drawings

[0022] The following drawings attached to this specification illustrate preferred embodiments of the present invention and serve to further understand the technical idea of the present invention together with the detailed description of the invention to be described later. The present invention should not be construed as being limited only to the matters described in such drawings.

[0023]

Figure 1

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Figure 7

[0024] Hereinafter, with reference to the accompanying drawings, preferred embodiments of the present invention will be described in detail so that those having ordinary knowledge in the technical field to which the present invention pertains can easily implement the present invention. However, the present invention can be realized in various different forms and is not limited or restricted by the following embodiments.

[0025] To clearly explain the present invention, detailed descriptions of parts not related to the explanation or known technologies related to the present invention that may obscure the gist of the present invention are omitted. When attaching reference numerals to the components of each drawing in this specification, the same or similar reference numerals are attached to the same or similar components throughout the specification.

[0026] Also, the terms and words used in this specification and the claims should not be construed as being limited to their ordinary or dictionary meanings. The inventors should interpret them in accordance with the meaning and concept that conform to the technical idea of the present invention in accordance with the principle that they can appropriately define the concept of the terms in order to explain their invention in the best way.

[0027] FIG. 1 is a perspective view of a battery module 1 according to an embodiment.

[0028] Referring to FIG. 1, the battery module 1 includes a plurality of battery cells to store electrical energy and can output the stored electrical energy to the outside via connection terminals. In the process of manufacturing the battery module 1 and utilizing the process, the battery module 1 can include an insulating sheet so that current does not leak from the internal cells and the storage and output functions of electrical energy do not decline. Also, in the process of welding and manufacturing the battery module 1, in order to prevent the battery cells located inside the battery module 1 from being damaged by welding spatter, the insulating sheet can have a structure protruding in a specific direction.

[0029] The battery module 1 can include a cell assembly 10, a frame 11, and an insulating part 12.

[0030] The cell assembly 10 can be a plurality of battery aggregates in which the M electrode assemblies are housed in a case like a pack. With such a structure, the cell assembly 10 can store a large amount of electrical energy and, if necessary, output the electrical energy and release it to the outside.

[0031] FIG. 2 is an exploded view of the frame 11 according to an embodiment.

[0032] Referring to FIG. 2, the frame 11 can form an accommodation space inside to accommodate the cell assembly 10. The frame 11 can protect the cell assembly 10 from external impacts and the environment by blocking the cell assembly 10 from the external space in a state where the cell assembly 10 is accommodated inside.

[0033] The frame 11 can include a main body 110, an end plate 111, and a cover plate 112.

[0034] The main body 110 can form an accommodation space. For example, the main body 110 includes a rectangular parallelepiped shape, and the front surface M3 and the rear surface M4 of the main body 110 can be located forward and backward with respect to the longitudinal direction. In this case, the front surface M3 and the rear surface M4 of the main body 110 can be open and communicate the accommodation space with the external space.

[0035] In this case, the above-mentioned front surface M3 and rear surface M4, and the first surface M1 and the second surface M2 described later can mean virtual surfaces formed by the main body 110.

[0036] Also, the first surface M1 of the main body 110 can be a surface parallel to the longitudinal direction. Different from the front surface M3 and the rear surface M4, the first surface M1 can be a surface formed by both side walls of the main body 110 that are not open. The insulating portion 12 described later can be attached to the inner surface of the side wall of the main body 110.

[0037] Furthermore, the second surface M2 of the main body 110 can be a surface parallel to the longitudinal direction. The second surface M2 of the main body 110 can also be opened like the front surface M3 and the rear surface M4. Here, the second surface M2 can mean a surface different from the first surface M1. For example, the second surface M2 can be the upper surface of the main body 110 opened on the upper side of the main body 110.

[0038] According to such a structure, when viewed from one side, the main body 110 can include a U shape. Specifically, based on the state seen from the front surface M3 or the rear surface M4, the main body 110 can have a U shape.

[0039] FIG. 3 is a perspective view illustrating a state in which the cell assembly 10 according to an embodiment is placed on the main body 110, and FIG. 4 is a perspective view of a state in which the cell assembly 10 according to an embodiment is placed on the main body 110.

[0040] Referring to FIGS. 3 and 4, with the cell assembly 10 positioned above the main body 110, the cell assembly 10 can move into the inner accommodation space of the main body 110 through the second surface M2. The cell assembly 10 can be connected and fixed to the inner surface of the main body 110 when placed in the accommodation space.

[0041] The end plates 111 can cover the front surface M3 and the rear surface M4 of the main body 110 and be connected to the main body 110. In other words, a pair of end plates 111 are respectively positioned in the front and rear directions with respect to the longitudinal direction of the main body 110, and can be welded to both end portions of the main body 110 corresponding to the front surface M3 and the rear surface M4.

[0042] The cover plate 112 can cover the second surface M2 of the main body 110 and be connected to the main body 110. For example, with the cell assembly 10 accommodated inside the main body 110, the cover plate 112 can cover the upper surface of the main body 110, that is, the second surface M2, to block the accommodation space and the external space from each other. In other words, the cover plate 112 can be welded to the main body 110 so that the cell assembly 10 is blocked from the external space.

[0043] The insulating portion 12 can ensure an insulating distance between the frame 11 and the cell assembly 10. In other words, the insulating portion 12 can function to prevent electricity from passing between the frame 11 and the cell assembly 10 through the space therebetween. For example, the insulating portion 12 can be provided inside the frame 11 and integrally formed with the frame 11. In other words, the insulating portion 12 can be positioned between the frame 11 and the cell assembly 10. That is, the insulating portion 12 is disposed inside the first surface M1 which is the side surface of the frame 11, and the cell assembly 10 can be positioned inside the frame 11 while sandwiching the insulating portion 12. Further, the insulating portion 12 can have a shape bent toward the cell assembly 10. A pair of insulating portions 12 can be disposed on both side surfaces of the frame 11.

[0044] FIG. 5 is an enlarged view of part A in FIG. 4, and FIG. 6 is an enlarged view of the upper side of part A in FIG. 4.

[0045] Referring to FIGS. 5 and 6, the insulating part 12 can include a side member 120 and a bending member 121.

[0046] The side member 120 can be connected to the inside of the first surface M1. In other words, the side member 120 can be connected to the inner surface of the side wall of the main body 110 forming the first surface M1 and can be arranged along the longitudinal direction of the main body 110.

[0047] The bending member 121 can be connected to one end of the side member 120 and can include a shape bent toward the cell assembly 10. For example, the bending member 121 can protrude from the side member 120 and be bent toward the cell assembly 10. Specifically, the bending member 121 can protrude from one side of the side member 120 close to the second surface M2 of the main body 110. More specifically, the bending member 121 can be formed to protrude from the side member 120 perpendicular to the longitudinal direction of the main body 110.

[0048] The bending member 121 can be located between the cell assembly 10 and the second surface M2. In other words, the bending member 121 can be located between the upper surface of the cell assembly 10 and the second surface M2. According to such a structure, the insulating distance between the cell assembly 10 and the frame 11 can be more ensured, and the bending member 121 can block the welding flame so that the welding flame generated in the process of welding the upper surface of the main body 110 of the cover plate 112 does not scatter toward the cell assembly 10.

[0049] The cell assembly 10 is spaced apart from the front surface M3 and the rear surface M4 by a predetermined distance, and a part of the side member 120 can be disposed in the space between the cell assembly 10 and the front surface M3 and the rear surface M4. That is, based on the state seen from above, the side members 120 are positioned on both side surfaces of the cell assembly 10, and in the longitudinal direction, the side member 120 is formed longer than the cell assembly 10 and can be connected to the front surface M3 and the rear surface M4 of the main body 110.

[0050] In a state where the cell assembly 10 is placed in the accommodation space, the distance between the cell assembly 10 and the second surface M2 can be shorter than the distance between the cell assembly 10 and the front surface M3 and the rear surface M4. Therefore, the bending member 121 is formed not in front of and behind the side member 120 but above the side member 120, and an insulation distance between the upper surface of the cell assembly 10 and the second surface M2 of the main body 110, that is, the cover plate 112, can be further ensured.

[0051] The insulating portion 12 can further include an annular member 122 having a shape bent in a direction opposite to the direction in which the bending member 121 is bent. For example, one end of the bending member 121 can be connected to the side member 120, and the annular member 122 can be connected to the other end of the bending member 121. The annular member 122 can include an annular shape. Also, one end of the annular member 122 is connected to the other end of the bending member 121, and the other end of the annular member 122 can include a shape bent toward the second surface M2 of the main body 110.

[0052] As a result, due to such structural features of the insulating portion 12, the insulating portion 12 can ensure a greater insulation distance between the frame 11 and the cell assembly. Specifically, the insulation distance is divided into a space distance and a creepage distance. The space distance means the shortest distance across the air between two conductive objects, and the creepage distance means the shortest distance along the surface of the insulating material between two conductive objects. That is, due to the structural features of the bent member 121 bent toward the cell assembly 10 and the ring member 122 bent again in the opposite direction, the insulation distance between the frame 11 and the cell assembly 10 can be better ensured in terms of both the space distance and the creepage distance.

[0053] Also, in that the distance between the cover plate 112 and the cell assembly 10 is shorter than the distance between the end plate 111 and the cell assembly 10, the battery module 1 can effectively utilize the insulation structure by arranging the bent member 121 and the ring member 122 between the cover plate 112 and the cell assembly 10.

[0054] Specifically, the space distance ensured by the bent member 121 and the ring member 122 can mean the insulation distance between the cell assembly 10 and the main body 110. More specifically, the space distance can mean the distance between the upper surface of the cell assembly 10 and the inner side surface of the main body 110. That is, the space distance can mean the insulation distance between the inner side surface of the main body 110 to which the insulating portion 12 is attached and the upper surface of the cell assembly 10. In this case, due to the bent member 121 and the ring member 122, the space distance can be 2 mm to 8 mm.

[0055] When the space distance is less than 2 mm, the insulation distance between the components inside the battery module 1 cannot be ensured, and a short - circuit phenomenon may occur. In other words, due to the characteristics of the battery module 1 that houses the cell assembly 10, when the space distance between the upper surface of the cell assembly 10 and the inner surface of the main body 110 becomes 2 mm or less, a current may flow between the cell assembly 10 and the main body 110, resulting in a short - circuit phenomenon, and problems such as damage and breakage of the battery module may occur.

[0056] Also, when the spatial distance exceeds 8 mm, the bending member 121 and the ring member 122 have to be formed longer, so that the battery module also occupies the internal space excessively, which may cause the energy density of the battery module to decrease or the weight of the battery module to increase unnecessarily. Moreover, the lengthened bending member 121 and ring member 122 may incline toward the cell assembly 10, resulting in a problem that the insulation distance cannot be ensured sufficiently.

[0057] Furthermore, the creepage distance ensured by the bending member 121 and the ring member 122 may mean the distance reaching from the cell assembly 10 along the outer surface of the insulating part 12 to the inner surface of the main body 110. In this case, due to the bending part 12, the creepage distance can be 8 mm to 16 mm.

[0058] When the creepage distance is less than 8 mm, the insulation distance between the components inside the battery module 1 cannot be ensured, and a short - circuit phenomenon may occur. In other words, when the distance reaching from the upper surface of the cell assembly 10 along the outer surface of the insulating part 12 to the inner surface of the main body 110 is less than 8 mm, a short - circuit phenomenon between the cell assembly 10 and the main body 110 occurs, and an electric current can flow between the cell assembly 10 and the main body 110. That is, due to the short - circuit phenomenon, the battery module may be damaged and broken, and dangerous problems such as a fire may occur.

[0059] When the creepage distance exceeds 16 mm, similarly, the bending member 121 and the ring member 122 have to be formed longer, so that the battery module occupies the internal space excessively, which may cause the energy density of the battery module to decrease or the weight of the battery module to increase unnecessarily. Moreover, the lengthened bending member 121 and ring member 122 may incline toward the cell assembly 10, resulting in a problem that the insulation distance cannot be ensured sufficiently.

[0060] However, the numerical ranges for the spatial distance and the creepage distance are merely examples, and the numerical ranges may vary according to design methods such as the model of the battery module and the voltage used, and the application environment.

[0061] FIG. 7 is a flowchart of a method for manufacturing a battery module 1 according to another embodiment.

[0062] Referring to FIG. 7, according to the method for manufacturing the battery module 1, an insulating portion 12 can be connected inside the frame 11, so that the cell assembly 10 housed inside is not damaged and the function of the battery module 1 can be prevented from degrading. For example, during the process of welding the frame 11, damage to the cell assembly 10 caused by welding spatter can be prevented, the yield of the battery module 1 can be increased, and the efficiency of the manufacturing process of the battery module 1 can be improved.

[0063] In this case, as described above, the frame 11 can include a main body 110, an end plate 111, and a cover plate 112. Further, the main body 110 can form a first surface M1, a second surface M2, a front surface M3, and a rear surface M4.

[0064] The method for manufacturing the battery module 1 can include an arranging step (S10), a placing step (S20), and a welding step (S30).

[0065] In the arranging step (S10), the insulating portion 12 can be arranged inside the frame 11. In other words, as described above, the insulating portion 12 can include a side member 120, a bending member 121, and a ring member 122. The side member 120 is arranged on both side walls of the main body 110 along the longitudinal direction of the main body 110, and the bending member 121 is formed to protrude from the upper side of the side member 120 and can be bent toward the cell assembly 10.

[0066] In the placing step (S20), the cell assembly 10 can move and be placed in the accommodation space. For example, in a state where the cell assembly 10 is located above the main body 110, the cell assembly 10 can move into the inner accommodation space of the main body 110 through the second surface M2.

[0067] In the welding step (S30), the cover plate 112 can cover the second surface M2 and be welded and connected to the main body 110.

[0068] According to such an order, the welding flame generated by the welding of the cover plate 112 and the main body 110 scatters toward the cell assembly 10, but the insulating part 12 blocks the welding flame so that the welding flame cannot reach the cell assembly 10, thereby preventing damage to the cell assembly 10.

[0069] The above description merely exemplarily explains the technical idea of the present invention. Those with ordinary knowledge in the technical field to which the present invention pertains can make various modifications and deformations without departing from the essential characteristics of the present invention.

[0070] Therefore, the embodiments disclosed in the present invention are not for limiting the technical idea of the present invention, but for explanatory purposes, and the scope of the technical idea of the present invention is not limited by such embodiments.

[0071] The protection scope of the present invention should be interpreted according to the following claims, and all technical ideas within the equivalent scope should be interpreted as being included in the scope of rights of the present invention.

Explanation of Reference Numerals

[0072] 1 Battery module 10 Cell assembly 11 Frame 12 Insulating part 110 Main body 111 End plate 112 Cover plate 120 Side member 121 Bending member 122 Ring member M1 The first surface of the main body M2 The second surface of the main body M3 The front surface of the main body M4 The rear surface of the main body S10 Arrangement step S20 Placement step S30 Welding step

Claims

1. A cell assembly, a frame that forms an accommodation space inside to accommodate the cell assembly, and an insulating portion disposed inside a first surface that is a side surface of the frame, wherein the insulating portion is located between the frame and the cell assembly and has a shape bent toward the cell assembly, a battery module.

2. The insulating portion includes a side member connected to the inside of the first surface, and a bent member connected to one end of the side member and including a shape bent toward the cell assembly, the battery module according to claim 1.

3. The frame includes a main body with a front surface and a rear surface located in front and rear with respect to the longitudinal direction being open, a second surface that is a surface parallel to the longitudinal direction being open, and forming the accommodation space, an end plate that covers the front surface and the rear surface and is connected to the main body, and a cover plate that covers the second surface and is connected to the main body, the battery module according to claim 2.

4. The first surface different from the second surface is formed on the main body parallel to the longitudinal direction of the main body, wherein the bent member protrudes from the side member and is bent toward the cell assembly, the battery module according to claim 3.

5. The bent member is located between the cell assembly and the second surface, the battery module according to claim 4.

6. The bent member protrudes from the side member perpendicular to the longitudinal direction of the main body, the battery module according to claim 4.

7. The cell assembly is spaced apart from the front surface and the rear surface by a predetermined distance, and a part of the side member is disposed in a space between the cell assembly and the front surface and the rear surface, the battery module according to claim 4.

8. In a state where the cell assembly is placed in the accommodation space, a distance between the cell assembly and the second surface is shorter than a distance between the cell assembly and the front surface and the rear surface, the battery module according to claim 4.

9. The insulating portion further includes an annular member connected to the other end of the bent member and including a shape bent in a direction opposite to the direction in which the bent member is bent, the battery module according to claim 2.

10. A method of manufacturing a battery module by positioning a cell assembly in an accommodation space with respect to a frame that forms an accommodation space inside, the frame including a main body that forms a first surface and an open second surface, and a cover plate connected to the second surface, an arranging step of arranging an insulating part including a side member connected to the inside of the first surface and a bent member that protrudes from the side member and has a shape bent toward the cell assembly; a placing step of moving the cell assembly through the second surface and placing it in the accommodation space; a welding step of covering the second surface with the cover plate and welding it to the main body. A method of manufacturing a battery module.

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