Battery module and method for manufacturing the 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 May 27, 2022 and Korean Patent Application No. 10-2023-0062576 filed May 15, 2023, and all contents disclosed in the documents of said Korean patent applications are incorporated herein by reference.

[0002] The present invention relates to a battery module and a method for manufacturing a battery module. [Background technology]

[0003] Generally, there are various types of secondary batteries, including nickel-cadmium batteries, nickel-metal hydride batteries, lithium-ion batteries, and lithium-ion polymer batteries. These secondary batteries are used not only in small products such as digital cameras, DVD players, MP3 players, mobile phones, PDAs, portable game devices, power tools, and electric bicycles, but also in large products that require high output, such as electric vehicles and hybrid vehicles, as well as in power storage devices and backup power storage devices that store surplus generated power and new / renewable energy.

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

[0005] A cell assembly can be manufactured by packing a plurality of electrode assemblies, and a battery module can be manufactured by housing the cell assembly in a frame. When the cell assembly is disposed inside the frame, a problem of reduced battery performance can occur 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 ensure an insulating distance between the frame and the cell assembly has been utilized. Therefore, there is an increasing need to devise an insulating sheet arrangement and structure to more effectively ensure an insulating distance between the frame and the cell assembly during the process of manufacturing a battery module.

[0006] In addition, during the welding process on the top surface of the frame with the cell assembly inside, the flames from the welding may splash and damage the cell assembly, which is why a battery module with a structure that prevents damage from welding spatter is needed. Summary of the Invention [Problem to be solved by the invention]

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

[0008] SUMMARY OF THE INVENTION One problem to be solved by the present invention is to provide a battery module that prevents damage to cell assemblies due to spatters that occur during the welding process of a frame. [Means for solving the problem]

[0009] A battery module according to an embodiment of the present invention includes a cell assembly, a frame forming an accommodation space therein for accommodating the cell assembly, and an insulating portion disposed on the inside of a first surface, which is a side surface of the frame, and the insulating portion may be positioned between the frame and the cell assembly and have 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 bending member connected to one end of the side member and including a shape bent toward the cell assembly.

[0011] The frame may include a main body having open front and rear surfaces located in front and rear of the longitudinal direction and an open second surface parallel to the longitudinal direction, forming the storage space, end plates covering the front and rear surfaces and connected to the main body, and a cover plate covering the second surface and connected to the main body.

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

[0013] The folding member may be located between the cell assembly and the second surface.

[0014] The bending member may be formed to protrude from the side member perpendicular to the longitudinal direction of the main body.

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

[0016] When the cell assembly is placed in the accommodation space, the distance between the cell assembly and the second surface may be shorter than the distance between the cell assembly and the front and rear surfaces.

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

[0018] A method for manufacturing a battery module by positioning a cell assembly in an accommodation space with respect to a frame including a body forming a first surface and an open second surface and a cover plate connected to the second surface, the frame forming an accommodation space inside, the method for manufacturing a battery module according to an embodiment of the present invention may include a positioning step of arranging an insulating part including a side member connected to the inside of the first surface and a bending member protruding from the side member and having a shape bent toward the cell assembly, a placing step of moving the cell assembly via the second surface and placing it in the accommodation space, and a welding step of welding the cover plate to the body so that the cover plate covers the second surface. [Effects of the Invention]

[0019] According to a preferred embodiment of the present invention, the insulation distance between the cell assembly and the frame is further ensured, thereby preventing a deterioration in performance due to an electrical phenomenon.

[0020] According to a preferred embodiment of the present invention, the yield of battery modules can be increased by preventing damage to cell assemblies due to spatters that occur during the frame welding process.

[0021] Other effects may be included that can be easily predicted by a person skilled in the art from the configuration according to the preferred embodiment of the present invention. [Brief explanation of the drawings]

[0022] The following drawings attached to this specification illustrate preferred embodiments of the present invention and, together with the detailed description of the invention described below, serve to further understand the technical concept of the present invention, and the present invention should not be interpreted as being limited solely to the matters depicted in such drawings.

[0023] [Figure 1] FIG. 1 is a perspective view of a battery module according to an embodiment. [Figure 2] FIG. 1 is an exploded view of a frame according to one embodiment. [Figure 3] FIG. 10 is a perspective view illustrating a cell assembly according to one embodiment being placed on a main body. [Figure 4] FIG. 1 is a perspective view of a cell assembly according to one embodiment mounted on a body. [Figure 5] FIG. 5 is an enlarged view of part A in FIG. 4. [Figure 6] FIG. 5 is an enlarged view of the upper side of part A in FIG. 4. [Figure 7] 10 is a flowchart of a method for manufacturing a battery module according to another embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0024]

[0030] The present invention will now be described in detail with reference to the accompanying drawings, in which:

[0031] A preferred embodiment of the present invention will be described in detail so that those skilled in the art can easily implement the present invention; however, the present invention may be embodied in various different forms and should not be construed as being limited to the following embodiments.

[0025] In order to clearly explain the present invention, detailed descriptions of parts that are not relevant to the description or related known technologies that may obscure the gist of the present invention are omitted, and when referring to components in each drawing in this specification, the same or similar reference symbols are used throughout the specification to refer to the same or similar components.

[0026] Furthermore, the terms and words used in this specification and claims should not be interpreted in a limited way to their ordinary or dictionary meanings, but should be interpreted in a way that is consistent with the technical idea of ​​the present invention, based on the principle that the inventors can appropriately define the concepts of terms in order to best explain their invention.

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

[0028] 1, a battery module 1 includes a plurality of battery cells, stores electrical energy, and outputs the stored electrical energy to the outside through connecting terminals. During the manufacturing process of the battery module 1 and its use, the battery module 1 may include an insulating sheet to prevent current leakage from the internal cells or degradation of the electrical energy storage and output functions. Furthermore, during the welding process of the battery module 1, the insulating sheet may have a structure that protrudes in a specific direction to prevent damage to the battery cells located inside the battery module 1 from welding spatter.

[0029] The battery module 1 may include a cell assembly 10 , a frame 11 and an insulator 12 .

[0030] The cell assembly 10 may be a collection of multiple batteries in which M electrode assemblies are housed in a pack-like case. With this structure, the cell assembly 10 can store a large amount of electrical energy and output and release the electrical energy to the outside as needed.

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

[0032] 2, the frame 11 forms an accommodation space inside and can accommodate the cell assembly 10. With the cell assembly 10 accommodated inside, the frame 11 isolates the cell assembly 10 from the external space, thereby protecting the cell assembly 10 from external impacts and the environment.

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

[0034] The main body 110 can form a storage space. For example, the main body 110 can have a rectangular parallelepiped shape, and the front surface M3 and rear surface M4 of the main body 110 can be located in front and rear in the longitudinal direction. In this case, the front surface M3 and rear surface M4 of the main body 110 can be open to communicate the storage space with the outside space.

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

[0036] Furthermore, the first surface M1 of the body 110 may be a surface parallel to the longitudinal direction. Unlike the front surface M3 and the rear surface M4, the first surface M1 may be a surface formed by both side walls of the body 110 that is not open. An insulating portion 12, which will be described later, may be attached to the inner surface of the side wall of the body 110.

[0037] Furthermore, the second surface M2 of the body 110 may be a surface parallel to the longitudinal direction. The second surface M2 of the body 110 may also be open like the front surface M3 and the rear surface M4. Here, the second surface M2 may refer to a surface different from the first surface M1. For example, the second surface M2 may be an upper surface of the body 110 that is open to the upper side of the body 110.

[0038] According to this structure, the main body 110 may have a U-shape when viewed from one side. Specifically, the main body 110 may have a U-shape when viewed from the front surface M3 or the rear surface M4.

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

[0040] 3 and 4, when the cell assembly 10 is positioned on the upper side of the main body 110, the cell assembly 10 can move into the inner storage space of the main body 110 via the second surface M2. When placed in the storage space, the cell assembly 10 can be connected to and fixed to the inner surface of the main body 110.

[0041] The end plates 111 may 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, the end plates 111 may be located in pairs at the front and rear of the main body 110 in the longitudinal direction, and may be welded to both ends of the main body 110 corresponding to the front surface M3 and the rear surface M4.

[0042] The cover plate 112 may cover the second surface M2 of the main body 110 and be connected to the main body 110. For example, the cover plate 112 may cover the upper surface, i.e., the second surface M2, of the main body 110 when the cell assembly 10 is housed inside the main body 110, thereby isolating the housing space from the outside space. In other words, the cover plate 112 may be welded to the main body 110 so that the cell assembly 10 is isolated from the outside 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 electrical communication 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 formed integrally with the frame 11. In other words, the insulating portion 12 can be located between the frame 11 and the cell assembly 10. That is, the insulating portion 12 can be located inside the first surface M1, which is a side surface of the frame 11, and the cell assembly 10 can be located inside the frame 11 with the insulating portion 12 sandwiched between them. Furthermore, the insulating portion 12 can have a shape bent toward the cell assembly 10. A pair of insulating portions 12 can be located on both side surfaces of the frame 11.

[0044] 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.

[0045] 5 and 6, the insulating portion 12 can include a side member 120 and a folding member 121.

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

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

[0048] The bending member 121 may be positioned between the cell assembly 10 and the second surface M2. In other words, the bending member 121 may be positioned between the upper surface of the cell assembly 10 and the second surface M2. With this structure, the insulation distance between the cell assembly 10 and the frame 11 may be further ensured, and the bending member 121 may block the welding flame generated during the welding process of the upper surface of the body 110 of the cover plate 112 so that the welding flame does not spread 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 portion of the side member 120 may be disposed in the space between the cell assembly 10 and the front surface M3 and the rear surface M4. That is, when viewed from above, the side members 120 are located on both sides of the cell assembly 10, and the side members 120 may be formed to be longer than the cell assembly 10 in the longitudinal direction and connected to the front surface M3 and the rear surface M4 of the main body 110.

[0050] When the cell assembly 10 is placed in the storage space, the distance between the cell assembly 10 and the second surface M2 may be shorter than the distance between the cell assembly 10 and the front surface M3 and the rear surface M4. Therefore, the bending members 121 are formed on the upper side of the side surface member 120, rather than on the front and rear of the side surface member 120, thereby ensuring a sufficient insulating distance between the upper surface of the cell assembly 10 and the second surface M2 of the main body 110, i.e., the cover plate 112.

[0051] The insulating part 12 may further include a ring member 122 having a shape bent in a direction opposite to the bending direction of the bending member 121. For example, one end of the bending member 121 may be connected to the side member 120, and the ring member 122 may be connected to the other end of the bending member 121. The ring member 122 may have a ring shape. In addition, one end of the ring member 122 may be connected to the other end of the bending member 121, and the other end of the ring member 122 may have a shape bent toward the second surface M2 of the main body 110.

[0052] As a result, the structural features of the insulating part 12 allow the insulating part 12 to further ensure the insulation distance between the frame 11 and the cell assembly. Specifically, the insulation distance is divided into clearance distance and creepage distance, where clearance distance refers to the shortest distance across air between two conductive objects, and creepage distance refers to the shortest distance along the surface of insulating material between two conductive objects. That is, the structural features of the bending member 121 bent toward the cell assembly 10 and the structural features of the ring member 122 bent again in the opposite direction allow the insulation distance between the frame 11 and the cell assembly 10 to be further ensured in terms of both clearance distance and creepage distance.

[0053] In addition, since 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 insulating structure by placing the bending member 121 and the ring member 122 between the cover plate 112 and the cell assembly 10.

[0054] Specifically, the spatial distance ensured by the bending member 121 and the ring member 122 may refer to the insulating distance between the cell assembly 10 and the main body 110. More specifically, the spatial distance may refer to the distance between the top surface of the cell assembly 10 and the inner side surface of the main body 110. In other words, the spatial distance may refer to the insulating distance between the inner side surface of the main body 110 to which the insulating portion 12 is attached and the top surface of the cell assembly 10. In this case, the spatial distance may be 2 mm to 8 mm due to the bending member 121 and the ring member 122.

[0055] If the clearance is less than 2 mm, a short circuit may occur due to an insufficient insulation distance between components inside the battery module 1. In other words, due to the characteristics of the battery module 1 that houses the cell assemblies 10, if the clearance between the top surface of the cell assembly 10 and the inner surface of the body 110 is 2 mm or less, a current may flow between the cell assembly 10 and the body 110, causing a short circuit and potentially damaging the battery module.

[0056] Furthermore, if the spatial distance exceeds 8 mm, the bending members 121 and the ring members 122 must be made longer, which may result in excessive internal space within the battery module, resulting in a decrease in the energy density of the battery module or an unnecessary increase in the weight of the battery module. Furthermore, the longer bending members 121 and the ring members 122 may be tilted toward the cell assembly 10, which may result in an insufficient insulation distance.

[0057] Furthermore, the creepage distance ensured by the bending member 121 and the ring member 122 may refer to the distance 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, the bending part 12 allows the creepage distance to be 8 mm to 16 mm.

[0058] If the creepage distance is less than 8 mm, the insulation distance between the internal components of the battery module 1 will not be ensured, and a short circuit may occur. In other words, if the distance from the top surface of the cell assembly 10 along the outer surface of the insulating portion 12 to the inner surface of the body 110 is less than 8 mm, a short circuit may occur between the cell assembly 10 and the body 110, and current may flow between the cell assembly 10 and the body 110. In other words, a short circuit may damage or destroy the battery module, and may cause dangerous problems such as a fire.

[0059] Similarly, if the creepage distance exceeds 16 mm, the bending members 121 and the ring members 122 must be made longer, which may result in excessive space inside the battery module, resulting in a lower energy density of the battery module or an unnecessary increase in the weight of the battery module. Furthermore, the longer bending members 121 and the ring members 122 may be tilted toward the cell assembly 10, which may result in an insufficient insulation distance.

[0060] However, the above numerical ranges for the clearance distance and creepage distance are merely examples, and the numerical ranges may vary depending on the design method and application environment, such as the model of the battery module and the voltage used.

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

[0062] 7, the manufacturing method of the battery module 1 allows the insulating portion 12 to be connected to the inside of the frame 11, preventing damage to the cell assemblies 10 housed therein and preventing deterioration of the functionality of the battery module 1. For example, damage to the cell assemblies 10 due to welding spatter during the process of welding the frame 11 can be prevented, increasing the yield of the battery module 1 and improving the efficiency of the manufacturing process of the battery module 1.

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

[0064] The manufacturing method of the battery module 1 may include an arrangement step (S10), a mounting step (S20), and a welding step (S30).

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

[0066] In the placing step (S20), the cell assembly 10 can be moved and placed in the storage space. For example, with the cell assembly 10 positioned on the upper side of the main body 110, the cell assembly 10 can be moved into the storage space inside the main body 110 via the second surface M2.

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

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

[0069] The above description is merely an illustrative example of the technical concept of the present invention, and various modifications and variations are possible by a person having ordinary knowledge in the technical field to which the present invention pertains, without departing from the essential characteristics of the present invention.

[0070] Therefore, the embodiments disclosed in the present invention are for illustrative purposes only and are not intended to limit the technical idea of ​​the present invention, and the scope of the technical idea of ​​the present invention is not limited by such embodiments.

[0071] The scope of protection of the present invention should be interpreted by the following claims, and all technical ideas within the scope equivalent thereto should be interpreted as being included in the scope of the present invention. [Explanation of symbols]

[0072] 1 Battery Module 10 Cell Assembly 11 frames 12 Insulation section 110 Main Unit 111 End plate 112 Cover Plate 120 Side member 121 Bending members 122 Ring member First side of the M1 body Second side of M2 body Front of the M3 unit Rear of M4 body S10 Placement Step S20 Placement step S30 Welding Step

Claims

1. A cell assembly; a frame forming an internal storage space for storing the cell assembly; an insulating portion disposed on the inside of a first surface that is a side surface of the frame, the insulating portion is located between the frame and the cell assembly and has a shape bent toward the cell assembly; The insulating portion includes a side member connected to an inner side of the first surface; a folding member connected to one end of the side member and having a shape folded toward the cell assembly; The frame is a main body having a front surface and a rear surface, which are located in front and rear of the main body in a longitudinal direction, open, and a second surface, which is a surface parallel to the longitudinal direction, open, and which forms the storage space; an end plate covering the front and rear surfaces and connected to the main body; a cover plate covering the second surface and connected to the body.

2. The first surface, which is different from the second surface, is formed on the main body parallel to a longitudinal direction of the main body, The battery module according to claim 1 , wherein the bending members protrude from the side members and are bent toward the cell assemblies.

3. The battery module according to claim 2 , wherein the folding member is located between the cell assembly and the second surface.

4. The battery module according to claim 2 , wherein the bending members are formed to protrude from the side members perpendicular to a longitudinal direction of the main body.

5. the cell assembly is spaced apart from the front and rear surfaces by a predetermined distance; The battery module according to claim 2 , wherein a portion of the side member is disposed in a space between the cell assembly and the front and rear sides.

6. The battery module according to claim 2 , wherein a distance between the cell assembly and the second surface is shorter than a distance between the cell assembly and the front and rear surfaces when the cell assembly is placed in the accommodation space.

7. The insulating portion is The battery module of claim 1 , further comprising a ring member connected to the other end of the bending member and having a shape bent in a direction opposite to the bending direction of the bending member.

8. A method for manufacturing a battery module, comprising: a frame including a body forming a first surface and an open second surface, and a cover plate connected to the second surface, and forming an accommodation space therein; and positioning a cell assembly in the accommodation space, a positioning step of positioning an insulating portion including a side member connected to an inner side 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 in which the cell assembly is moved via the second surface and placed in the accommodation space; and welding the cover plate to cover the second surface and to the body.

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