Battery module, method for manufacturing same, and battery pack

Abstract

The present invention relates to a battery module in which the number of components is reduced, an assembly process is simplified to improve production efficiency, and heat transfer between cells can be effectively prevented, and a battery pack comprising the same. The battery module according to the present invention comprises: a battery cell unit assembly comprising a plurality of battery cell units; and an end frame covering both ends of the battery cell unit assembly in the longitudinal direction of the battery cell unit, in which the battery cell unit may include: a battery cell laminate in which at least one or more battery cells are laminated; and a cell cover surrounding a top side portion and both side portions of the cell stack in the width direction.

Description

Technical Field

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to Korean Patent Application No. 10-2022-0100240 filed on August 10, 2022, Korean Patent Application No. 10-2022-0100241 filed on August 10, 2022, and Korean Patent Application No. 10-2023-0062426 filed on May 15, 2023, which are hereby incorporated by reference in their entirety. Technical Field

[0004] The present invention relates to a battery module, a method for manufacturing the battery module, and a battery pack, and more particularly, to a secondary battery module including a plurality of battery cells, a method for manufacturing the battery module, and a battery pack including the battery module. Background Art

[0005] In recent years, energy prices have risen due to the depletion of fossil fuels, people's concerns about environmental pollution have increased, and the demand for environmentally friendly alternative energy is becoming an indispensable factor in future life. Therefore, research on various power generation technologies such as solar energy, wind energy and tidal energy is continuing, and power storage devices such as batteries for more efficient use of generated electrical energy are also receiving great attention.

[0006] In addition, as technology develops and demand for electronic mobile devices and electric vehicles using batteries increases, demand for batteries as energy sources is rapidly increasing. Therefore, many studies have been conducted on batteries that can meet various demands.

[0007] Batteries that store electrical energy can generally be divided into primary batteries and secondary batteries. Such primary batteries are disposable consumable batteries. On the other hand, such secondary batteries are rechargeable batteries made by using materials in which oxidation and reduction processes between electric current and materials can be repeated. That is, when the material is subjected to a reduction reaction by electric current, charging is performed. When the material is subjected to an oxidation reaction by electric current, discharging is performed. Such charging-discharging is repeated to generate electricity.

[0008] Recently, as the demand for large-capacity structures in addition to being used as energy storage has been increasing, the demand for battery packs in which a plurality of secondary batteries or battery modules are gathered has been increasing, and therefore, the demand for battery modules has been increasing. For example, secondary batteries installed in vehicles, energy storage systems (ESS), etc., a plurality of secondary batteries are connected to increase output and power storage to form a battery module, and then the battery modules are connected to form a battery pack.

[0009] A battery module according to the related art may be manufactured by arranging a plurality of battery cells inside a frame and assembling the plurality of battery cells while blocking an opening of the frame using a stacking plate and an end plate.

[0010] Reference Figure 1 , which illustrates the appearance and the appearance after decomposition of a battery module having a conventional structure, the secondary batteries are stacked and arranged as a cell stack having a rectangular parallelepiped shape, and the stacking plate 2 is covered on the surface where the positive electrode lead and the negative electrode lead do not protrude among the six surfaces defined by the rectangular parallelepiped shape (selectively as needed), and the busbar frame 3 is covered on the two surfaces from which the positive electrode lead and the negative electrode lead protrude. The positive electrode lead and the negative electrode lead are electrically connected to the terminals (negative terminal and positive terminal) provided on the busbar frame 3.

[0011] In addition, a single frame 4 provided in a cylindrical shape with both sides opened is coupled to cover the outer side of the laminated plate 2. In addition, the single frame 4 is inserted so that the busbar frame 3 is exposed, and then, the end plate 5 is coupled to cover the busbar frame 3.

[0012] The end plate 5 and the single frame 4 are both made of metal, and the end plate 5 and the single frame 4 are assembled together by welding.

[0013] The battery module 1 according to the prior art manufactured in this way may have a structure in which all surfaces of the battery cells are blocked, and therefore, there is a limitation that an explosion may occur when gas is discharged or a flame occurs. That is, the battery module according to the prior art has a limitation in that it cannot effectively prevent heat propagation between the battery cells disposed inside.

[0014] In addition, since the end plates 5 are coupled after the bus bar frames 3 are coupled, there is a limitation that the number of assembly processes increases. That is, the battery module according to the related art has a large number of components and is complicated to assemble, thereby deteriorating the efficiency of the manufacturing process.

[0015] Therefore, in order to address this limitation, there is a need for a battery module that can effectively prevent heat propagation between battery cells while reducing the number of components and simplifying an assembly process, and a battery pack including the battery module. Summary of the invention

[0016] Technical issues

[0017] The present invention is invented to solve the above problems, and an object of the present invention is to provide a battery module capable of improving production efficiency by reducing the number of components and simplifying the assembly process to effectively prevent heat propagation between battery cells and a battery pack including the battery module.

[0018] Technical Solution

[0019] A battery module according to the present invention may include: a battery cell assembly including a plurality of battery cell units; and an end frame configured to cover both ends of the battery cell assembly based on the longitudinal direction of the battery cell units, wherein the battery cell units include: a battery cell stack in which at least one or more battery cells are stacked; and a battery cell cover configured to surround two side portions and an upper portion of the battery cell stack in a width direction.

[0020] The cell cover may include an upper plate disposed above the cell stack to cover a top surface of the cell stack; and a side plate connected to be bent from the upper plate to cover a side surface of the cell stack.

[0021] The side plates may be disposed to be in contact with side surfaces of the cell stack.

[0022] Gas discharge holes are defined in both ends of the upper plate based on the longitudinal direction.

[0023] The battery cell stack may include more than one and less than three battery cells.

[0024] The cell cover may be made of metal material.

[0025] The cell cover may be arranged to be in contact with the end frame.

[0026] The portion of the cell cover that contacts the end frame may be welded.

[0027] The battery cell unit assembly may further include an insulating plate disposed between adjacent battery cell units and including an insulating material.

[0028] Both ends of the insulating plate may be disposed to be in contact with the end frames based on a longitudinal direction.

[0029] A battery pack according to the present invention may include: a battery module according to the present invention and a cooling plate disposed below the plurality of battery modules, wherein the cooling plate may be configured to cover lower portions of openings of the battery modules.

[0030] A battery module according to the present invention may include: a cell stack in which a plurality of cells are stacked, electrode leads protruding from the cells at each of the two ends in the longitudinal direction; and an end frame connected to an end plate and a bus bar assembly, the end plate being connected to each of the two ends of the cell stack, the bus bar assembly being connected to the end plate and the electrode leads of each cell being electrically connected to the bus bar assembly.

[0031] The end frames may be coupled such that the end plates are disposed closer to the cell stack than the bus bar assembly.

[0032] An opening hole through which the electrode lead passes may be defined in the end plate so that the electrode lead is connected to the bus bar assembly through the opening hole.

[0033] A plurality of first holes may be punched in the bus bar assembly, and the electrode lead may pass through each of the first holes to facilitate electrical connection to a terminal provided on the bus bar assembly.

[0034] A second hole may be additionally defined in the bus bar assembly, the second hole being spaced apart from the first hole and through which the electrode lead does not pass.

[0035] The first hole may be set to a size sufficient to provide an empty space after the electrode lead is passed therethrough.

[0036] The bus bar assembly may be made of a synthetic resin material having relatively low rigidity, and the end plate may be made of a metal material having relatively high rigidity.

[0037] One side of the bus bar assembly may be bent to provide a bent portion, and the end plate may be bent to an opposite side of the bent portion to provide a folded portion.

[0038] According to the method for manufacturing a battery module of the present invention, the method may include the following steps: a cell stack manufacturing process, which manufactures a cell stack by stacking cell cells and cell covers made of metal material, wherein electrode leads protrude from the cell to each of the two ends in the longitudinal direction; an end frame manufacturing process, which manufactures an end frame connected to an end plate and a bus bar assembly, the end plate being made of metal material, the bus bar assembly being connected to the end plate and the electrode lead of each cell being electrically connected to the bus bar assembly; and a connection process, which connects the end frame to the cell stack by welding the end plate to the cell cover.

[0039] Technical Effects

[0040] The battery module according to the present invention may include: a battery cell unit assembly, which includes a plurality of battery cell units; an end frame, which covers both ends of the battery cell unit assembly based on the longitudinal direction of the battery cell, and the battery cell unit may include a battery cell stack in which at least one or more battery cells are stacked and a battery cell cover surrounding the two sides and the upper part of the battery cell stack in the width direction.

[0041] Therefore, the number of components required to manufacture the battery module can be reduced to improve the economic efficiency of the manufacturing process.

[0042] Furthermore, the efficiency of the manufacturing process can be improved by simplifying the assembly process of the battery module.

[0043] In addition, heat propagation between battery cells can be effectively prevented to improve the stability of the battery module.

[0044] In addition, secondary damage due to heat spread caused by gas leakage or flame can be prevented.

[0045] Furthermore, the energy density per volume of the battery module can be increased by reducing wasted space.

[0046] In addition, in the structure according to the prior art, when welding the bus bar assembly and the electrode lead, and when welding the single frame and the end plate after the welding of the electrode lead is completed, it may be necessary to separately install a welding jig (although the installation of the welding jig needs to be performed at least twice). However, in the present invention, when welding the cell cover and the end plate, the bus bar assembly and the electrode lead can also be welded at the same time, so the number of installation and removal of the welding jig can be reduced.

[0047] The effects of the present invention are not limited to the above description, and therefore, more various effects are involved in this specification. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] Figure 1 1 is a schematic perspective view and an exploded perspective view of a battery module according to the prior art.

[0049] Figure 2 This is a schematic perspective view illustrating a battery module according to Embodiment 1 of the present invention.

[0050] Figure 3 This is a schematic exploded perspective view of the battery module according to the first embodiment of the present invention.

[0051] Figure 4 is a schematic perspective view illustrating a cell cover of a battery module according to Embodiment 1 of the present invention.

[0052] Figure 5 is a schematic perspective view illustrating an end plate of a battery module according to Embodiment 1 of the present invention.

[0053] Figure 6 It is an example Figure 2 Schematic front view of a battery module.

[0054] Figure 7 is a schematic perspective view illustrating a battery module according to Embodiment 2 of the present invention.

[0055] Figure 8 is a schematic perspective view illustrating a cell cover of a battery module according to a second embodiment of the present invention.

[0056] Fig. 9 is a schematic perspective view illustrating an end plate of a battery module according to Embodiment 2 of the present invention.

[0057] Fig.10 1 is a schematic exploded perspective view of a battery pack according to a third embodiment of the present invention. DETAILED DESCRIPTION

[0058] Hereinafter, the preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art can easily implement the present invention. However, the present invention can be implemented in several different forms and is not limited or restricted by the following examples.

[0059] In order to clearly illustrate the present invention, the detailed description of the related known technology that is irrelevant to the description or may unnecessarily obscure the gist of the present invention has been omitted, and in this specification, the reference numerals are added to the components in each figure. In this case, the same or similar reference numerals are assigned to the same or similar elements throughout the specification.

[0060] Furthermore, the terms or words used in the specification and claims should not be restrictively interpreted as ordinary meanings or dictionary-based meanings, but should be interpreted as meanings and concepts consistent with the scope of the present invention on the basis that the inventor can appropriately define the concepts of the terms to best describe and explain the principles of his or her invention.

[0061] Implementation Method 1

[0062] The present invention provides a battery module 10 as Embodiment 1.

[0063] Figure 2 is a schematic perspective view illustrating a battery module 10 according to Embodiment 1 of the present invention, Figure 3 1 is a schematic exploded perspective view of the battery module 10 according to the first embodiment of the present invention.

[0064] Reference Figure 2 and Figure 3 , the battery module 10 according to Embodiment 1 of the present invention may include a battery cell unit assembly 100 and an end frame 200 .

[0065] The cell unit assembly 100 of the battery module 10 according to the first embodiment of the present invention may include a plurality of cell units 110. Specifically, the battery module 10 may include: a cell unit assembly 100 having a generally rectangular parallelepiped shape, which includes a plurality of cell units 110; and an end frame 200 assembled on the front and rear surfaces of the cell unit assembly 100.

[0066] Reference Figure 2 and Figure 3 , the cell unit assembly 100 of the battery module 10 according to Embodiment 1 of the present invention may include four cell units 110. Therefore, the four cell units 110 may be stacked side by side to provide the cell unit assembly 100.

[0067] Figure 41 is a schematic perspective view illustrating a cell cover 120 of a battery module 10 according to Embodiment 1 of the present invention.

[0068] As an example of a configuration for effectively preventing heat propagation between cells, the cell unit 110 included in the cell unit assembly 100 of the battery module 10 according to Embodiment 1 of the present invention may include a cell stack 111 and a cell cover 120 .

[0069] The cell stack 111 of the cell unit 110 may be provided by stacking at least one or more battery cells.

[0070] Preferably, for the purpose of preventing heat transfer between cells in the battery module 10 of the present invention, the cell stack 111 constituting the cell unit 110 may include three or fewer cells. That is, the number of cells constituting the cell stack 111 may be more than one and less than three.

[0071] The cell stack 111 according to Embodiment 1 of the present invention may be provided by stacking three cells side by side. Here, the cell may be a pouch-shaped cell.

[0072] Reference Figure 4 , the cell cover 120 of the cell unit 110 may be arranged to surround the cell stack 111. Specifically, the cell cover 120 may be arranged to surround both sides and the upper portion of the cell stack 111 in the width direction. Therefore, the cell stack 111 of the cell unit 110 may be arranged inside the cell cover 120 in a state where both ends and the lower portion in the longitudinal direction are open.

[0073] The cell cover 120 of the cell unit 110 according to Embodiment 1 of the present invention may have a substantially rectangular parallelepiped shape with three surfaces opened. Therefore, the cell unit assembly 100 provided by stacking the cell units 110 each having a substantially rectangular parallelepiped shape may also have a substantially rectangular parallelepiped shape.

[0074] As an example of a configuration surrounding the cell stack 111 , the cell cover 120 of the cell unit 110 according to Embodiment 1 of the present invention may include a top plate 121 and side plates 122 .

[0075] The top plate 121 of the cell cover 120 may cover the top surface of the cell stack 111. Specifically, the top plate 121 may be disposed on the upper portion of the cell stack 111 to cover the top surface of the cell stack 111. In addition, the top plate 121 may have a plate shape with a generally rectangular cross section.

[0076] The side plate 122 of the cell cover 120 may cover the side surface of the cell stack 111. Specifically, the side plate 122 may be bent to be connected to each of both ends of the upper plate 121 in the width direction, and be disposed at each side of both sides of the cell stack 111. Here, the top plate 121 and the side plate 122 may be connected to each other substantially vertically.

[0077] The cell cover 120 including the top plate 121 and the side plate 122 may be shared and used in various types of battery modules.

[0078] As an example of a configuration for fixing the cell stack 111, the side plate 122 of the cell cover 120 according to Embodiment 1 of the present invention may contact the side surface of the cell stack 111. Specifically, the side plate 122 may be provided so that the outer surface of the cell stack 111 and the inner surface of the side plate 122 contact each other.

[0079] The cell cover 120 may include a pair of side plates 122, and a space may be defined between the pair of side plates 122. When the cell stack 111 consisting of three cells is disposed in contact with the side plates 122 in this space, the cell stack 111 may be sandwiched between the pair of side plates 122. Therefore, the cell stack 111 may be easily fixed between the pair of side plates 122.

[0080] The cell cover 120 of the cell unit 110 according to Embodiment 1 of the present invention may be made of a metal material as an example of a configuration for preventing heat propagation between the cell stacks 111. Specifically, the cell cover 120 may be made of a highly heat-resistant metal material.

[0081] Since the cell cover 120 is made of a metal material, the flame and high-temperature gas generated from the cell stack 111 of one cell unit 110 can be prevented from spreading to other adjacent cell units 110, and the cell cover 120 can withstand internal combustion. Here, the end frame 200 can block the diffusion at both open ends of the cell cover 120, and thus, the diffusion can be blocked at the open lower portion of the cell cover 120 by the cooling plate 20 of the battery pack 1. This will be described in detail later.

[0082] As an example of a configuration for delaying heat conduction between the battery cells 110, the battery cell assembly 100 of the battery module 10 according to Embodiment 1 of the present invention may further include an insulating plate 130. That is, the insulating plate 130 may be selectively disposed between adjacent battery cells 110 to reduce temperature, improve insulation performance, and mitigate impact during stacking.

[0083] The insulating plate 130 may be disposed between adjacent battery cell units 110 and may include an insulating material. In addition, the insulating plate 130 may have a plate shape with a generally rectangular cross-section and may have the same cross-sectional area as the side plate 122 of the cell cover 120 .

[0084] The insulating plate 130 may include a material having an excellent insulating effect, and examples of the insulating plate 130 may include silicone, aerogel, and the like.

[0085] As an example of a configuration for effectively delaying heat conduction between the battery cell units 110, both ends of the insulating plate 130 according to the first embodiment of the present invention may be arranged to contact the end plates based on the longitudinal direction. Therefore, the adjacent battery cell units 110 may not contact each other due to the insulating plate 130, and thus the insulation effect may be effectively maintained.

[0086] The battery cell unit assembly 100 of the battery module 10 according to Embodiment 1 of the present invention may include an insulating plate 130 to effectively delay heat conduction between the battery cell units 110 .

[0087] By coupling a cell stack 111 including one or more cells to a cell cover 120 , a cell unit 110 may be provided to have an overall hexahedral shape, and a positive lead 11 and a negative lead 12 protruding from the cell stack 111 may protrude from both sides of the cell unit 110 , respectively.

[0088] In addition, the end frame 200 can be configured to be in a state in which the bus bar assembly 210 in which the electrode leads (positive lead and negative lead) of each battery cell stack 111 are electrically connected to the terminals 213 and 214 and the end plate 220 for protecting and finishing the battery cell stack 111 (especially the electrode lead portion) from external physical impacts are integrally connected to each other.

[0089] Figure 5 is a schematic perspective view illustrating an end plate 200 of a battery module 10 according to Embodiment 1 of the present invention, and Figure 6 It is an example Figure 2 Schematic front view of a battery module 10.

[0090] As an example of a configuration for fixing the battery cell unit assembly 100 , the battery module 10 according to Embodiment 1 of the present invention may include an end frame 200 .

[0091] The end frame 200 of the battery module 10 may cover both ends of the battery cell unit assembly 100. Specifically, both ends of the battery cell unit assembly 100 may be covered based on the longitudinal direction of the battery cell unit 110. Therefore, the flame may be prevented from spreading through both open ends of the battery cell unit assembly 100 by the end frame 200.

[0092] Reference Figure 5 , the end frame 200 according to Embodiment 1 of the present invention may be configured such that the end plate 220 is disposed at the inner side and thus may be coupled closer to the cell stack 111 than the bus bar assembly.

[0093] Therefore, the end plate 220 may have a plurality of opening holes 221 through which the electrode leads 11 and 12 pass, so that the positive electrode lead 11 and the negative electrode lead 12 protruding from the individual cell stack 111 pass through the end plate 220 instead of bypassing the end plate to extend to the bus bar assembly 210. The number, size, and arrangement structure of the opening holes 221 may be determined according to the positions and number of the electrode leads 11 and 12. Therefore, the electrode leads 11 and 12 may be connected to the bus bar assembly 210 through the opening holes 221.

[0094] A plurality of first holes 211 through which the electrode leads 11 and 12 pass may also be punched in the bus bar assembly 210, so that the electrode leads 11 and 12 may pass through the first holes 211 and be electrically connected to the terminals 213 and 214 provided on the bus bar assembly 210. That is, the ends of the electrode leads 11 and 12 may be connected to the terminals 213 and 214 by welding or brazing.

[0095] A second hole 212 may be additionally defined, which is spaced apart from the first hole 211 and through which the electrode leads 11 and 12 do not pass. The second hole 212 may be provided so that when gas leaks or a flame occurs in the battery cell, the gas and the flame leak to the outside, but the direction of the leakage is adjusted so as not to cause an explosion.

[0096] Reference Figure 6 , four first holes 211 may be defined in the bus bar assembly 210 of the end frame 200 according to Embodiment 1 of the present invention. Here, each first hole 211 may be defined to have a size sufficient to define an empty space after the electrode leads 11 and 12 pass therethrough, so that when gas or flame is generated, the gas or flame is exhausted through the first hole 211. In addition, the first hole 211 may be defined in a portion of the bus bar assembly 210 corresponding to a portion where the battery cell unit 110 is disposed.

[0097] That is, the first hole 211 and the second hole 212 may be defined in the bus bar assembly 210 according to Embodiment 1 of the present invention to prevent the battery cell unit 110 from exploding.

[0098] The first hole 211 and the second hole 212 may be provided in various shapes to facilitate gas discharge. The first hole 211 and the second hole 212 of the bus bar assembly 210 according to the first embodiment of the present invention may be provided to have a substantially rectangular cross section. In addition, the first hole 211 and the second hole 212 may be defined to pass from one side of the bus bar assembly 210 to the opposite side.

[0099] Since the first hole 211 and the second hole 212 are defined in the bus bar assembly 210 of the end frame 200 according to Embodiment 1 of the present invention, explosion due to increased internal pressure of the battery cell unit 110 can be prevented. In addition, secondary damage due to heat propagation caused by gas leakage or flame can be prevented.

[0100] The bus bar assembly 210 may be made of a synthetic resin material having relatively low rigidity so that the rest of the assembly except the terminals 213 and 214 has electrical insulation properties and is relatively light weight. On the other hand, the end plate 220 may be made of a metal material having relatively high rigidity to protect the battery cell stack from external loads and impacts.

[0101] The two end frames 200 may be coupled to respectively cover both sides of the electrode leads 11 and 12 protruding from the two cell stacks 111 , and the end plates 220 may be coupled to face the electrode leads 11 and 12 .

[0102] The end plate 220 or the bus bar assembly 210 may be coupled to the cell stack by other coupling means, but in this embodiment, the cell stack and the end frame may be securely coupled to each other.

[0103] That is, the cell cover 120 provided in the present embodiment may be made of a weldable metal, and a portion of the end plate 220 in contact with the cell cover 120 in a state of being in contact with or temporarily fixed to the cell cover 120 may be welded to be coupled.

[0104] Here, if Figure 5 As shown, the bus bar assembly 210 may be bent at one side thereof to provide a bent portion 215, and the end plate 220 may be bent at a side opposite to the bent portion 215 to provide a folded portion 222, so that the cell stack is inserted into the end frame and temporarily fixed before welding.

[0105] The end frame 200 of the battery module 10 according to Embodiment 1 of the present invention may further include a component such as a bus bar for electrical connection between the battery cell units 110 .

[0106] As an example of a method of connecting the cell unit assembly 100 and the end frame 200 , welding may be used in the battery module 10 according to Embodiment 1 of the present invention.

[0107] The cell cover 120 of the cell unit 110 included in the cell unit assembly 100 may be disposed to contact the end frame 200. Specifically, both ends of the cell cover 120 in the longitudinal direction may contact the end frame 200. Here, contact portions of the cell cover 120 and the end frame 200 may be coupled to each other by welding.

[0108] Therefore, both ends of the cell cover 120 may be disposed to contact the end frame 200 , and the contact portions may be welded, and thus, the cell unit assembly 100 may be fixed and coupled to the end frame 200 .

[0109] When the battery cell unit assembly 100 is coupled to the end frame 200 by welding, both open surfaces of the battery cell unit 110 in the longitudinal direction may be covered by the end frame 200 .

[0110] As described above, the battery module 10 may include a cell unit assembly 100 and an end frame 200, and the cell unit assembly 100 may include a plurality of cell units 110 and an insulating plate 130. In addition, each cell unit 110 may include a cell stack 111 and a cell cover 120 surrounding the cell stack 111.

[0111] As described above, the battery module 10 according to the first embodiment of the present invention can be composed of relatively few parts, so the economic efficiency of the manufacturing process can be improved, and the efficiency of the manufacturing process can be improved because the assembly process is simple. In addition, the battery module 10 can prevent the battery cell unit 110 from exploding due to increased pressure, and also prevent or delay the spread of flame and heat between the battery cell units 110 to improve the stability of the battery module 10. In addition, a module structure with various capacities and sizes can be manufactured using the battery cell unit 110 having a specific shape.

[0112] Hereinafter, a method for manufacturing the battery module 10 according to Embodiment 1 of the present invention will be described in detail.

[0113] The method for manufacturing the battery module 10 may include a cell stack manufacturing process, an end frame manufacturing process, and a coupling process.

[0114] In the cell stack manufacturing process, the cell unit 110 may be manufactured by stacking a cell stack 111 of which electrode leads 11 and 12 protrude from both ends in a longitudinal direction, respectively, and a cell cover 120 made of metal.

[0115] In more detail, an electrode assembly in which a positive electrode, a separator, and a negative electrode are repeatedly stacked may be embedded in a bag together with an electrolyte, and then a charge / discharge process, an aging process, a test process, etc. may be performed according to a known method for manufacturing a battery cell to manufacture a single battery cell. Then, the battery cell cover 120 may be coupled to one or more battery cells and stacked to manufacture the battery cell unit 110.

[0116] Here, the positive lead 11 of the battery cell may protrude from one end of the bag, and the negative lead 12 may protrude from the other end of the bag, and the battery cell unit 110 in which one or more battery cells and the battery cell cover 120 are stacked may be manufactured to have an overall hexahedral shape.

[0117] In addition, in the end frame manufacturing process, the end plate 220 made of metal and the bus bar assembly 210 made of synthetic resin may be manufactured to be integrated with each other.

[0118] The end plate 220 made of metal may be manufactured by a metal processing method such as casting, forging, cutting, rolling, and milling. In addition, the end plate 220 manufactured first may be inserted into an injection mold and then manufactured as a whole with the bus bar assembly 210 by an insert molding method in which a polymer resin is injected into the outside of the end plate 220.

[0119] The polymer resin injected into the end plate 220 from the outside may be cooled to form the exterior appearance of the bus bar assembly 210 , and after cooling, the terminals 213 and 214 , etc. may be additionally mounted to manufacture the bus bar assembly 210 .

[0120] Alternatively, in addition to the above insert injection, the end frame 200 may also be manufactured by another manufacturing method of integrally molding a metal material and a synthetic resin material. If the end plate 220 is made of a synthetic resin material instead of a metal material, the end plate 220 may be manufactured using a method such as two-shot molding in which various types of synthetic resin materials are manufactured as one piece. Alternatively, the end frame 200 may also be manufactured by separately manufacturing the end plate 220 using a metal material, then manufacturing the bus bar assembly 210 using a synthetic resin material, and then bonding the end plate 220 to the bus bar assembly 210 by an adhesive.

[0121] In addition, a coupling process of coupling the end frame 200 to the cell unit assembly 100 by welding the end plate 220 to the cell cover 120 may be performed.

[0122] The end plate 220 and the cell cover 120 provided in this embodiment may be made of metals that are welded to each other to be coupled. Therefore, the coupling may be achieved by welding the end plate 220 to the cell cover 120 while the end plate 220 is in contact with the cell cover 120 .

[0123] Here, welding with the end plate 220 may be performed even if there is at least one cell cover 120 , but it is preferred that the cell cover 120 is provided to be coupled to each cell stack 111 so as to be welded as continuously as possible along the edge of the end plate 220 .

[0124] Therefore, according to the prior art, the end plate can be set at the outermost side, and the bus bar assembly and the end plate can be connected to each other separately, but in the present invention, the end plate 220 and the bus bar assembly 210 can be manufactured as one piece with each other, and then, the end plate 220 can be fixed to the battery cell stack to reduce the assembly process.

[0125] In the present invention having the above configuration, the end plate 220 and the bus bar assembly 210 can be coupled to provide an end frame 200, and therefore, when compared with a structure according to the prior art in which the bus bar assembly 210 and the end plate 220 can be separately installed, the assembly process can be simplified to further improve production efficiency.

[0126] In addition, since the single frame and the laminated plates are removed from the structure according to the related art, the assembling process can be simplified to reduce weight.

[0127] The end frame 200 can be connected so that the end plate 220 is set closer to the cell stack than the bus bar assembly 210, so that the fixing points of the end plate 220 and the cell stack can be set relatively inside, and no wasted space can be provided to further improve the energy density per volume of the battery module.

[0128] An opening hole 221 may be formed in the end plate 220, and a first hole 211 and a second hole 212 may be formed in the bus bar assembly 210. Therefore, even if gas leakage or flame occurs in the battery cell unit assembly 100, the gas or flame may be discharged to the outside through the first hole 211 and the second hole 212 to prevent heat propagation.

[0129] One or more cell covers 120 may be stacked on the cell unit 110 together with the cell stack 111 to increase the rigidity of the cell unit 110 itself. In addition, the cell cover 120 and the end plate 220 may be made of metal and coupled to each other by welding to simplify the assembly process.

[0130] For example, in the structure according to the prior art, when the bus bar assembly and the electrode lead are welded, and when the single frame and the end plate are welded after the welding of the electrode lead is completed, it may be necessary to separately install a welding fixture (although the welding fixture needs to be installed at least twice). However, in the present invention, when the battery cell cover 120 and the end plate 220 are welded, the bus bar assembly 210 and the electrode leads 11 and 12 can also be welded at the same time, so the number of installations and installations of the welding fixture can be reduced.

[0131] Implementation Method 2

[0132] The present invention provides another type of battery module 10 ′ as a second embodiment.

[0133] The battery module 10′ according to embodiment 2 of the present invention differs from the battery module 10 according to embodiment 1 of the present invention in terms of the number of battery cells constituting the battery cell stack, the number of battery cell units 110′ constituting the battery cell unit assembly 100′, the shape of the end frame 200′, and the assembly method of the battery cell cover 120′ and the end frame 200′.

[0134] Hereinafter, a detailed description of the same configuration as that of the battery module 10 according to Embodiment 1 of the present invention will be omitted.

[0135] Figure 5 1 is a schematic perspective view illustrating an end plate of a battery module 10 ′ according to Embodiment 2 of the present invention.

[0136] The battery module 10' according to Embodiment 2 of the present invention may include a cell unit assembly 100' and an end frame 200'. Here, the cell unit assembly 100' may include twelve cell units 110'.

[0137] Figure 6 1 is a schematic perspective view illustrating a cell cover 120 ′ of a battery module 10 ′ according to Embodiment 2 of the present invention.

[0138] The battery cell unit 110' according to Embodiment 2 of the present invention may include a battery cell and a battery cell cover 120'. Specifically, the battery cell unit 110' may include one battery cell and a battery cell cover 120' surrounding the battery cell. Here, the battery cell may be arranged so that a free space is defined between the outer surface of the battery cell and the inner surface of the battery cell cover 120'.

[0139] The cell cover 120' may include a top plate 121' and a side plate 122' bent and connected to the top plate 121'. Here, the top plate 121' may cover the upper portion of the cell, and the side plate 122' may cover both sides of the cell. Similar to Embodiment 1, the cell cover 120' may have a generally rectangular parallelepiped shape with three sides open.

[0140] As an example of a configuration for preventing the battery cell unit 110 ′ from exploding, according to Embodiment 2 of the present invention, a gas discharge hole 123 may be defined in the upper plate 121 ′ of the cell cover 120 ′.

[0141] Reference Figure 6 , the gas discharge hole 123 may be defined at each side of both ends of the upper plate 121 ′ in the longitudinal direction. Therefore, according to Embodiment 2 of the present invention, two gas discharge holes 123 may be defined in the upper plate 121 ′ of the cell cover 120 ′.

[0142] The gas discharge hole 123 may be provided in various shapes to facilitate gas discharge. The gas discharge hole 123 of the upper plate 121' according to Embodiment 2 of the present invention may be defined to have an approximately circular cross-section.

[0143] The gas discharge hole 123 may be defined to pass through from one surface of the upper plate 121' facing the battery cell to another surface opposite to the battery cell. Therefore, high temperature gas generated due to ignition of the battery cell in the battery cell unit 110' may be discharged from the inside of the battery cell unit 110' to the outside of the battery cell unit 110'.

[0144] Since the gas discharge hole 123 is defined in the upper plate 121' of the cell cover 120' according to Embodiment 2 of the present invention, explosion due to pressure increase inside the cell unit 110' can be prevented. In addition, secondary damage caused by heat propagation due to gas leakage or flame can be prevented.

[0145] Figure 7 is a schematic perspective view illustrating a battery module according to Embodiment 2 of the present invention.

[0146] As an example of a configuration for fixing the cell unit assembly 100', the battery module 10' according to Embodiment 2 of the present invention may include an end frame 200'. In addition, the cell unit assembly 100' according to Embodiment 2 may include a greater number of cell units 110' than Embodiment 1, and therefore, the horizontal length of the end frame 200' according to Embodiment 2 may be longer than that of the end frame 200 of Embodiment 1.

[0147] As an example of a method of connecting the cell unit assembly 100 ′ and the end frame 200 ′, the cell unit assembly 100 ′ according to Embodiment 2 of the present invention may be inserted between the folded portion 222 ′ of the end frame 200 ′ and the bent portion 215 ′ of the bus bar assembly 210 ′.

[0148] A space may be defined between the folded portion 222' and the bent portion 215' extending in parallel to each other. Here, the battery cell unit assembly 100' may have the same height as the height of the space. Therefore, when both ends are set to contact the end plate 220' of the end frame 200', the battery cell unit assembly 100' may be inserted into the space between the folded portion 222' and the bent portion 215', and thus, the unit assembly 100' may be fixed to the end frame 200'.

[0149] The battery module 10' according to the second embodiment of the present invention can prevent the explosion of the battery cell 110' due to the increase of pressure by simplifying the connection of the battery cell unit assembly 100' and the end frame 200', and prevent or delay the spread of flame between the battery cell units 110' to improve the stability of the module 10' in the manufacturing process of the battery module 10' and the efficiency of the battery module 10'. In addition, the battery cell unit 110 having a certain shape can be used to manufacture a battery module structure with various capacities and sizes.

[0150] Implementation 3

[0151] The present invention provides a battery pack 1 as a third embodiment.

[0152] Figure 8 1 is a schematic exploded perspective view of a battery pack 1 according to a third embodiment of the present invention.

[0153] The battery pack 1 according to Embodiment 3 of the present invention may include a battery module 10 and a cooling plate 20 .

[0154] In order to provide a large amount of electric energy, a battery pack 1 in which a plurality of battery modules 10 are assembled may be used. Therefore, the battery pack 1 according to Embodiment 3 of the present invention may include a plurality of battery modules 10 according to Embodiment 1. Specifically, the battery pack 1 may include six battery modules 10.

[0155] The cooling plate 20 of the battery pack 1 may be disposed under the plurality of battery modules 10. Here, the cooling plate 20 may have a plate shape having a substantially rectangular cross-section, and the cooling plate 20 may cover the lower portion of the opening of the battery module 10.

[0156] The cooling plate 20 may further include a cooling channel through which a coolant for cooling passes. Therefore, the cooling plate 20 may effectively reduce the temperature of the battery cells placed inside the battery module 10 through the lower portion of the opening.

[0157] The battery pack 1 according to Embodiment 3 of the present invention may further include a case for covering upper portions of the battery modules 10 and additional components for electrically connecting the battery modules 10 to each other.

[0158] The battery pack 1 shown in the third embodiment of the present invention is merely an example. Therefore, the effects of the present invention can be achieved by battery packs having various structures including different types of battery modules or different numbers of battery modules.

[0159] While embodiments of the present invention have been described with reference to specific embodiments, it will be apparent to those skilled in the art that various changes and modifications may be made without departing from the spirit and scope of the invention as defined in the appended claims.

[0160] [reference numerals list]

[0161] 1: Battery Pack

[0162] 10, 10′: Battery module

[0163] 11: Positive lead

[0164] 12: Negative lead

[0165] 20: Cooling plate

[0166] 100, 100′: battery cell assembly

[0167] 110, 110′: battery cell

[0168] 111: Battery cell stack

[0169] 120, 120′: Battery cover

[0170] 121, 121′: upper board

[0171] 122, 122′: Side panels

[0172] 123: Gas discharge hole

[0173] 130: Insulation board

[0174] 200, 200′: End frame

[0175] 210, 210′: Busbar assembly

[0176] 211: First hole

[0177] 212: Second hole

[0178] 213, 214: Terminal

[0179] 215, 215': bending part

[0180] 220, 220′: End plate

[0181] 221: Opening hole

[0182] 222, 222′: Folding part

Claims

1. A battery module, comprising: A battery cell unit assembly, the battery cell unit assembly comprising a plurality of battery cell units; as well as an end frame configured to cover both ends of the battery cell unit assembly based on the longitudinal direction of the battery cell unit, Wherein, the battery cell unit comprises: A battery cell stack in which at least one or more battery cells are stacked; and A cell cover is configured to surround both side portions and an upper portion of the cell stack in a width direction.

2. The battery module according to claim 1, wherein: The battery cover comprises: an upper plate disposed above the battery cell stack to cover a top surface of the battery cell stack; and A side plate is connected to be bent from the upper plate to cover a side surface of the battery cell stack.

3. The battery module according to claim 2, wherein: The side plate is disposed in contact with the side surface of the cell stack.

4. The battery module according to claim 2, wherein: Gas discharge holes are defined in both ends of the upper plate based on the longitudinal direction.

5. The battery module according to claim 1, wherein: The battery cell stack includes one or more and three or less battery cells.

6. The battery module according to claim 1, wherein: The battery cell cover is made of metal material.

7. The battery module according to claim 1, wherein: The cell cover is disposed to be in contact with the end frame.

8. The battery module according to claim 7, wherein: A portion of the cell cover that contacts the end frame is welded.

9. The battery module according to claim 1, wherein: The battery cell unit assembly further includes an insulating plate, which is disposed between adjacent battery cell units and includes an insulating material.

10. The battery module according to claim 9, wherein: Both ends of the insulating plate are disposed to be in contact with the end frame based on the longitudinal direction.

11. A battery pack, comprising: The battery module according to any one of claims 1 to 10; as well as a cooling plate disposed below the plurality of battery modules, The cooling plate is configured to cover a lower portion of the opening of the battery module.

12. A battery module, comprising: A cell stack in which a plurality of cells are stacked, and an electrode lead protrudes from the cells to each of both ends in a longitudinal direction; as well as An end frame coupled to an end plate coupled to each of the two ends of the battery cell stack and a bus bar assembly coupled to the end plate and to which the electrode lead of each battery cell is electrically connected.

13. The battery module according to claim 12, wherein: The end frames are coupled such that the end plates are disposed closer to the battery cell stack than the bus bar assembly.

14. The battery module according to claim 13, wherein: An opening hole through which the electrode lead passes is defined in the end plate so that the electrode lead is connected to the bus bar assembly through the opening hole.

15. The battery module according to claim 14, wherein: A plurality of first holes are punched in the bus bar assembly, and The electrode lead passes through each of the first holes to be electrically connected to a terminal provided on the bus bar assembly.

16. The battery module according to claim 15, wherein: A second hole is additionally defined in the bus bar assembly, the second hole being spaced apart from the first hole and through which the electrode lead does not pass.

17. The battery module according to claim 15, wherein: The first hole is set to a size sufficient to provide an empty space after the electrode lead is passed therethrough.

18. The battery module according to claim 13, wherein: The bus bar assembly is made of a synthetic resin material having relatively low rigidity, and the end plate is made of a metal material having relatively high rigidity.

19. The battery module according to claim 12, wherein: One side of the bus bar assembly is bent to provide a bent portion, and the end plate is bent to an opposite side of the bent portion to provide a folded portion.

20. A method for manufacturing a battery module, the method comprising the following steps: A cell stack manufacturing process, which manufactures a cell stack by stacking cells and cell covers made of a metal material, wherein an electrode lead protrudes from the cell to each of both ends in a longitudinal direction; an end frame manufacturing process of manufacturing an end frame coupled to an end plate and a bus bar assembly, the end plate being made of a metal material, the bus bar assembly being coupled to the end plate and the electrode lead of each battery cell being electrically connected to the bus bar assembly; as well as A coupling process of coupling the end frame to the cell stack by welding the end plate to the cell cover.

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