Battery module and battery pack including same

Abstract

A battery module according to an embodiment of the present invention comprises: a first sub-module and a second sub-module, each of which comprises a battery cell assembly in which a plurality of battery cells are stacked, and a bus bar frame that covers, from at least one side, a bus bar that electrically connects the battery cells to each other and the battery cell assembly; a module housing that accommodates the first sub-module and the second sub-module at the same time; and a terminal assembly located at a portion overlapping with a region between the first sub-module and the second sub-module, in which an opening portion is formed in a portion of the module housing overlapping with the module extension portion, and the terminal assembly is connected to the terminal bus bar of each of the first sub-module and the second sub-module through the opening portion.

Description

Technical Field

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims the benefit of Korean Patent Application No. 10-2022-0181906 filed in the Korean Intellectual Property Office on December 22, 2022, and Korean Patent Application No. 10-2023-0185439 filed in the Korean Intellectual Property Office on December 19, 2023, the entire contents of which are incorporated herein by reference in their entirety.

[0003] The present disclosure relates to a battery module and a battery pack including the same, and more particularly, to a battery module having a cooling structure using insulating oil and a battery pack including the same. Background Art

[0004] With the development of mobile device technology and the increase in demand for mobile devices, the demand for secondary batteries as energy sources has increased rapidly. In particular, secondary batteries have attracted considerable attention as energy sources for power-driven devices such as electric bicycles, electric vehicles, hybrid electric vehicles, and mobile devices such as mobile phones, digital cameras, laptop computers, and wearable devices.

[0005] In small mobile devices, one or two or three battery cells are used per device, while medium or large devices such as vehicles require high power and large capacity. Therefore, medium or large battery modules having a plurality of battery cells electrically connected to each other are used.

[0006] Meanwhile, when a plurality of battery cells are connected in series or in parallel to configure a battery module and / or a battery pack, a battery module consisting of at least one battery cell is usually configured first, and then a battery pack is configured by using at least one battery module and adding other components.

[0007] Since the battery cells that constitute such medium or large battery modules are composed of rechargeable and dischargeable secondary batteries, such high-output, large-capacity secondary batteries generate a large amount of heat during the charging and discharging process. In this case, the heat generated from multiple battery cells can be superimposed in a narrow space, so that the temperature can rise faster and more violently. In other words, a battery module stacked with multiple battery cells and a battery pack equipped with these battery modules can obtain a higher output, but the heat generated from the battery cells during the charging and discharging process is not easy to remove. When the heat dissipation of the battery cells is not properly performed, the degradation of the battery cells will be accelerated, the service life will be shortened, and the possibility of explosion or fire will increase.

[0008] Furthermore, in the case of a battery module included in a vehicle battery pack, the battery module is often exposed to direct sunlight and may be placed under high temperature conditions such as in summer or in desert areas. Furthermore, since a plurality of battery modules are centrally arranged to increase the mileage of the vehicle, a flame or heat generated in any one battery module may easily propagate to an adjacent battery module, which may eventually lead to a fire or explosion of the battery pack itself.

[0009] Figure 1 is a diagram showing a heat dissipation path in a conventional battery module.

[0010] Reference Figure 1 The conventional battery module 30 includes a cell assembly 70 having battery cells 60 stacked in a preset direction and a module frame 40 accommodating the cell assembly 70, wherein the cell assembly 70 is fixedly located on a thermally conductive resin layer 50 on a lower surface of the module frame 40. In this case, in order to cool the heat generated in the cell assembly 70, a heat dissipation device is provided at the bottom of the cell assembly 70. Figure 1 The heat sink 90 faces the bottom of the module frame 40 in the −z-axis direction, and a thermal pad 80 for heat transfer may be further installed between the heat sink 90 and the bottom of the module frame 40 .

[0011] However, since the heat sink 90 does not receive heat transfer while being in direct contact with the battery cell assembly 70, the cooling efficiency is not very high, and a cooling path is formed in one direction (-z axis direction) of the width direction of the battery cell, which may cause a temperature gradient.

[0012] Therefore, in order to extend the service life of the battery module and / or battery pack, the cooling efficiency of the battery module / battery pack must be improved so that the temperature of the battery cells does not increase. Summary of the invention

[0013] Technical issues

[0014] An object of the present disclosure is to provide a battery module that directly cools battery cells and thus maximizes cooling performance, and a battery pack including the battery module.

[0015] Another object of the present disclosure is to provide a battery module that integrates the structures of a battery module and a battery pack, adopts a high-rigidity case to ensure sealing reliability, and maximizes energy density, and a battery pack including the battery module.

[0016] The objects of the present disclosure are not limited to the above objects, and other objects not mentioned herein should be clearly understood by those skilled in the art from the following detailed description and accompanying drawings.

[0017] Technical Solution

[0018] According to one embodiment of the present disclosure, a battery module is provided, which includes: a first submodule and a second submodule, each of the first submodule and the second submodule including a battery cell assembly in which a plurality of battery cells are stacked, and a bus bar electrically connecting the battery cells and a bus bar frame covering the battery cell assembly on at least one side; a module housing, the module housing simultaneously accommodating the first submodule and the second submodule; and a terminal assembly, the terminal assembly being located at a portion overlapping with an area between the first submodule and the second submodule, wherein an opening is formed in a portion of the module housing, and the terminal assembly is connected to a terminal bus bar of each of the first submodule and the second submodule through the opening.

[0019] The battery module may further include a bracket positioned in the opening, and a sealing member formed between the bracket and the terminal assembly.

[0020] The terminal assembly may include a connection cable having a flexible property, a terminal housing coupled with the connection cable, and an upper cover covering an upper portion of the terminal housing connected with the bracket.

[0021] The module case is formed of a high-rigidity material, and the high-rigidity material may include fiber reinforced plastic (FRP) which is a composite material.

[0022] The battery module may further include a flange portion formed on a side surface of the module case, and a module fastening member coupled to the flange portion.

[0023] According to one embodiment of the present disclosure, a battery pack is provided, comprising: a plurality of battery modules, wherein a first battery module and a second battery module included in the plurality of battery modules are adjacent to each other, wherein the first battery module and the second battery module are electrically connected through a first terminal assembly and a second terminal assembly, and wherein the first terminal assembly and the second terminal assembly are connected to each other through a fixing member.

[0024] Respective flange portions of the first battery module and the second battery module overlap each other, and the first battery module and the second battery module may be coupled by a module fastening member passing through the overlapping flange portions.

[0025] The coupling portion including the module fastening member may form a rigid beam of the battery pack.

[0026] The fixing member may be fastened to the module housing by a fastening member.

[0027] The battery pack further includes a battery pack frame surrounding the plurality of battery modules from the front, rear, left and right sides, respectively, wherein the battery pack frame may be divided into a plurality of portions so that the plurality of battery modules correspond to the front, rear, left and right sides, respectively.

[0028] The battery pack further includes a frame fastening part formed on a side surface of the module case, wherein at least one of the pack frames may be connected to the battery module by inserting a frame fastening member into the frame fastening part.

[0029] A mounting hole is formed in at least one of the battery pack frames, the mounting hole being arranged to correspond to a hole formed in a mounting portion of an end plate of the battery module, and the frame fastening member may be inserted into the mounting hole and the hole formed in the mounting portion.

[0030] The overall structure of the pack frame may have a shape in which upper and lower portions of the battery module are exposed.

[0031] The upper portion and the lower portion of the module case formed of a high-rigidity material may form an upper cover and a lower cover of the pack frame.

[0032] The first terminal assembly and the second terminal assembly may be respectively connected to terminal bus bars having polarities different from each other.

[0033] Beneficial Effects

[0034] According to an embodiment, the cooling performance of the battery module may be maximized by directly cooling the battery cells through the circulation of insulating oil.

[0035] Furthermore, sealing reliability can be ensured by applying a high-rigidity housing.

[0036] In addition, the energy density can be maximized by integrating the structure of battery modules and battery packs.

[0037] Effects obtainable from the present disclosure are not limited to the above-mentioned effects, and other additional effects not mentioned herein will be clearly understood by those skilled in the art from the description and the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 is a diagram showing a heat dissipation path in a conventional battery module.

[0039] Figure 2 is a perspective view showing a battery module according to an embodiment of the present disclosure.

[0040] Figure 3 yes Figure 2 An exploded perspective view of a battery module.

[0041] Figure 4 is to show the terminal assembly with Figure 2 A perspective view of the state of battery module connection.

[0042] Figure 5 It is shown that the Figure 4 Figure 2 is a diagram of a terminal assembly in a battery module.

[0043] Figure 6 It is shown that the Figure 4 An exploded perspective view of the battery cell assembly in a battery module.

[0044] Figure 7 The busbar frame and Figure 6 A perspective view of a battery cell assembly before connection.

[0045] Figure 8 is a perspective view illustrating coupling between a bus bar bolt and a bus bar nut according to an embodiment of the present disclosure.

[0046] Fig. 9 is shown by connecting Figure 4 A perspective view of a battery pack formed by multiple battery modules.

[0047] Fig.10 It is a front view of a state where adjacent battery modules are connected together.

[0048] Fig.11 is a perspective view illustrating coupling between a battery module and a cooling assembly according to an embodiment of the present disclosure.

[0049] Fig.12 is a diagram illustrating a front surface or a rear surface of a battery module according to an embodiment of the present disclosure.

[0050] Fig.13 and Fig.14 is a front view illustrating coupling of a cooling assembly in a battery pack according to an embodiment of the present disclosure.

[0051] Fig.15 is a schematic diagram showing a connection relationship of cooling components in a battery pack according to a comparative example.

[0052] Fig.16 is a schematic diagram showing the connection relationship of cooling components in a battery pack according to an embodiment of the present disclosure.

[0053] Fig.17 and Fig.18 is a diagram illustrating coupling of a battery module and a pack frame according to an embodiment of the present disclosure.

[0054] Fig.19is a plan view showing a structure of connecting terminal assemblies in a battery pack according to an embodiment of the present disclosure. DETAILED DESCRIPTION

[0055] Hereinafter, various embodiments of the present disclosure will be described in detail with reference to the accompanying drawings so that those skilled in the art can easily implement the embodiments. The present disclosure can be modified in various different ways and is not limited to the embodiments set forth herein.

[0056] Parts irrelevant to the description will be omitted to clearly describe the present disclosure, and the same reference numerals denote the same elements throughout the specification.

[0057] In addition, in the drawings, the size and thickness of each element are arbitrarily shown for the convenience of description, and the present disclosure is not necessarily limited to those sizes and thicknesses shown in the drawings. In the drawings, the thickness of layers, regions, etc. are exaggerated for the sake of clarity. In the drawings, the thickness of parts and regions is exaggerated for the convenience of description.

[0058] In addition, throughout the specification, unless otherwise stated, when a part is referred to as “including” or “comprising” a certain component, it means that the part may further include other components, without excluding other components.

[0059] Furthermore, throughout the specification, when referred to as a “plane”, it means when the target portion is viewed from the upper side, and when referred to as a “cross section”, it means when the target portion is viewed from the side of the cross section cut vertically.

[0060] Figure 2 is a perspective view showing a battery module according to an embodiment of the present disclosure. Figure 3 yes Figure 2 An exploded perspective view of a battery module. Figure 4 is to show the terminal assembly with Figure 2 A perspective view of the state of battery module connection. Figure 5 It is shown that the Figure 4 Figure 2 is a diagram of a terminal assembly in a battery module. Figure 6 It is shown that the Figure 4 An exploded perspective view of the battery cell assembly in a battery module. Figure 7 The busbar frame and Figure 6 A perspective view of a battery cell assembly before connection.

[0061] Reference Figure 2 , Figure 3 , Figure 6 and Figure 7According to the present embodiment, the battery module 100 includes: a first submodule 100a and a second submodule 100b, each of the first submodule and the second submodule including a cell assembly 120 in which a plurality of battery cells 110 are stacked; and a bus bar electrically connecting the battery cells 110, and a bus bar frame 130 covering the cell assembly 120 on at least one side; and a module housing 200, which simultaneously accommodates the first submodule 100a and the second submodule 100b.

[0062] The battery cells arranged in the battery cell assembly 120 may be in a bag shape, which can maximize the number of cells stacked per unit area. The battery cells arranged in a bag shape may be manufactured by accommodating an electrode assembly including a positive electrode, a negative electrode, and a separator in a battery cell housing of a laminate and then heat-sealing the sealed portion of the battery cell housing. However, the battery cells do not need to be arranged in a bag shape per se, and may be arranged in a square, cylindrical, or various other forms, as long as the storage capacity required for the device to be installed in the future can be achieved.

[0063] Meanwhile, the battery cell arranged in a bag shape may have a length, a width and a thickness, and the length direction, the width direction and the thickness direction of the battery cell may be perpendicular to each other. Figure 2 , Figure 6 and Figure 7 As shown, the length direction of the battery cell can be defined as the y-axis direction, the width direction as the z-axis direction, and the thickness direction as the x-axis direction. Therefore, the length direction of the battery cell assembly 120 can be defined as the y-axis, and the stacking direction of the battery cells in the battery cell assembly 120 (hereinafter referred to as the stacking direction) can be defined as the x-axis direction.

[0064] exist Figure 6 In the embodiment, the cooling fins 210 may be arranged between adjacent battery cells 110, wherein the cooling fins 210 may be cooled by receiving the transfer of heat generated from the battery cells 110 and contacting with the insulating oil. In addition, an insulating plate 115 may be formed at the outermost side of the battery cell assembly 120.

[0065] exist Figure 7 In the embodiment, each battery cell of the battery cell assembly 120 may include an electrode lead protruding from both sides in the length direction (y-axis direction). One end of the electrode lead is located inside the battery cell and is thus electrically connected to the positive electrode or negative electrode of the electrode assembly in the battery cell, and the other end of the electrode lead protrudes outside the battery cell and can be electrically connected to the bus bar mounted on the bus bar frame 130.

[0066] The bus bar frame 130 is located on one surface of the battery cell assembly 120, and thus may be provided to cover one surface of the battery cell assembly 120 and simultaneously guide the connection between the battery cell assembly 120 and an external device. The bus bar frame 130 may be coupled to the front surface or the rear surface of the battery cell assembly 120 in a state where the outermost surface of the battery cell assembly 120 is pressed by the insulating plate 115. The bus bar frame 130 may be provided on the front surface and the rear surface of the battery cell assembly 120, respectively. Among them, the front surface or the rear surface may be the surface where the electrode lead of the corresponding battery cell in the battery cell assembly 120 is located.

[0067] The busbar frame 130 may include a slit 131 into which the electrode lead of the battery cell can be inserted. The electrode lead passing through the slit 131 can be connected to a busbar 132 mounted on one surface of the busbar frame 130. The electrode lead of each battery cell is connected to the busbar 132, so that the plurality of battery cells of the cell assembly 120 can be electrically connected to each other. In addition, the slit 131 can be used as a channel for the coolant to flow into the interior of the battery module 100. Since the coolant in the present embodiment is injected through the end plate 400, the injected coolant can pass through the slit 131 of the busbar frame 130 and contact the battery cell. In addition, the coolant that has been in contact with the battery cell can pass through the slit 131 and be discharged to the outside of the battery module 100.

[0068] The bus bar frame 130 may be made of an electrically insulating material. The bus bar frame 130 includes an insulating material, thereby being able to restrict the bus bars 132 from contacting other portions of the battery cell except for the electrode leads and preventing an electrical short circuit from occurring.

[0069] The busbar frame 130 may be mounted with terminal busbars 133 and 134 that provide electrical connection between the battery cell assembly 120 and an external device. The terminal busbars 133 and 134 are high potential terminals and may be connected to the HV connection assembly 500 (see FIG. 1 ) that electrically connects the two battery modules 100. Fig.19 ). The terminal bus bars 133 and 134 may include a first terminal bus bar 133 and a second terminal bus bar 134, each of which may have a different polarity from each other.

[0070] Figure 8 is a perspective view illustrating coupling between a bus bar bolt and a bus bar nut according to an embodiment of the present disclosure.

[0071] Reference Figure 8, the first terminal bus bar 133 can be connected to the bus bar bolt 138 and the bus bar nut 139. As will be described later, the bus bar bolt 138 and the bus bar nut 139 can be used to facilitate the connection between the first terminal bus bar 133 and the terminal assembly 300. The first terminal bus bar 133 is arranged so that one end protrudes along the length direction of the battery cell, and the protruding end can have a surface parallel to the ground (xy plane). A hole into which the bus bar bolt 138 can be inserted is formed on the above-mentioned one surface of the first terminal bus bar 133, and the bus bar bolt 138 passing through the hole on one side of the first terminal bus bar 133 can be connected to the bus bar nut 139 located on the other side. Among them, although the drawings show that the bus bar bolt 138 is inserted from the upper side to the lower side, this is not always the case, and the present embodiment can also include the case where the bus bar bolt 138 is inserted from the lower side to the upper side.

[0072] Meanwhile, although the first terminal bus bar 133 is mainly described above, the above description may also be applied to the second terminal bus bar 134. For example, the second terminal bus bar 134 mounted on the bus bar frame 130 may have one surface parallel to the ground. In addition, the second terminal bus bar 134 may be provided with a bus bar bolt 138 passing through a hole formed on the above one surface and a bus bar nut 139 coupled to the bus bar bolt 138.

[0073] Reference Figure 8 , the sensing unit 140 may be located on one surface of the busbar frame 130. The sensing unit 140 is provided for implementing a low voltage (LV) connection, wherein the LV connection may refer to a sensing connection for detecting and controlling the voltage of a battery cell. The sensing unit 140 may include a sensing terminal for detecting a voltage value of the busbar 132, a temperature sensor for detecting a temperature inside the battery module 100, and a connecting member connecting the sensing terminal and the temperature sensor. For example, the sensing unit 140 may include a PCB (printed circuit board) and / or an FFC (flexible flat cable). Alternatively, the sensing unit 140 may include a flexible printed circuit board (FPCB0.

[0074] Refer again Figure 2 The module case 200 according to the present embodiment can be used to protect the battery cell assembly 120 and the electrical components connected thereto from external physical impact. The module case 200 can accommodate the battery cell assembly 120 and the electrical components connected thereto in its internal space.

[0075] The module housing 200 may be provided with various structures. For example, the module housing 200 may be in the shape of a metal plate in which an upper surface, a lower surface, and two side surfaces are integrated. Among them, the module housing may be manufactured by extrusion molding. However, differently from this, the module housing 200 may be provided in the form of a U-shaped frame and a plate in which one of the upper and lower surfaces is coupled to the two side surfaces, and may also be provided as two L-shaped frames in which one of the upper and lower surfaces is coupled to one side surface. At this time, each frame or plate may be manufactured by press molding.

[0076] The respective components of the module case 200 may be coupled by welding or the like in a state where corresponding corners contact each other, or may be fixed to each other by a separate fastening member. In addition, the respective components of the module case 200 may be made of a metal material having a predetermined strength.

[0077] The module case 200 may be provided in an open shape along a length direction (y-axis direction) of the cell assembly 120 , and may accommodate the cell assembly 120 and then be coupled to the end plates 400 provided on the front and rear surfaces of the cell assembly 120 .

[0078] The battery module 100 according to the present embodiment may have a dual structure. Here, the dual structure may be a structure in which the battery module 100 includes two battery cell assemblies 120. In the dual structure, the two battery cell assemblies 120 accommodated in one module housing 200 may be arranged in the length direction (y-axis direction). In addition, the two battery cell assemblies 120 accommodated in one module housing 200 may be arranged so that the front surface or the rear surface of the battery cell assembly where the electrode lead is located faces each other.

[0079] Specifically, refer to Figure 3 According to the present embodiment, the battery module 100 includes a first battery cell assembly 121 and a second battery cell assembly 122. Figure 2 and Figure 3As shown, since the cell assembly 120 is inserted into the module housing 200 in the length direction, one of the front and rear surfaces of the first cell assembly 121 is located inside the module housing 200, and the other of the front and rear surfaces may be located outside the module housing 200, that is, located on an open surface. In a conventional structure, two end plates 400 are provided in each of the first cell assembly 121 and the second cell assembly 122, and each end plate 400 is formed with two openings for exposing the positive terminal bus bar 133 and the negative terminal bus bar 134. However, in the structure of the present embodiment, one of the front and rear surfaces of the first cell assembly 121 and the second cell assembly 122 faces each other inside the module housing 200, and the other of the front and rear surfaces may be arranged outside. Therefore, the number of end plates 400 provided in the first cell assembly 121 and the second cell assembly 122 is reduced from 4 to 2, so that the number of openings formed in the end plates 400 can be reduced.

[0080] At the same time, refer to Figure 2 , Figure 3 and Figure 7 In the dual-structure battery module 100 according to the present embodiment, since the terminal bus bars 133 and 134 are located in the module housing 200, as shown in FIG. Figure 2 and Figure 3 As shown, the module housing 200 may be formed with a Figure 7 The terminal bus bars 133 and 134 are connected to the module terminal portion 201 of the external device. The module terminal portion 201 may be formed on an upper surface of the module case 200 .

[0081] Figure 5 The terminal assembly 300 may be mounted on the module terminal portion 201, wherein the module terminal portion 201 may have a concave shape to facilitate the installation of the terminal assembly 300. The module terminal portion 201 may be formed in the central portion of the module housing 200. The central portion may be a portion including the center based on the length direction (y-axis direction) of the battery module 100.

[0082] The module housing 200 may include two module terminal portions 201. Each module terminal portion 201 may include two terminal holes 202 corresponding to the terminal bus bars 133 and 134. At this time, one of the two terminal holes 202 is used to connect to one of the positive and negative electrodes of the first battery cell assembly 121, and the other of the two terminal holes 202 may be used to connect to one of the positive and negative electrodes of the second battery cell assembly 122.

[0083] In the battery cell assembly 120 of the present embodiment, the terminal bus bars 133 and 134 may be arranged to be biased to one side in the stacking direction. Therefore, the four terminal bus bars 133 and 134 of the two battery cell assemblies 120 housed in the same module housing 200 may be arranged to intersect with each other in one direction. Therefore, one module terminal portion 201 corresponds to all two battery cell assemblies 120, and the two terminal holes 202 included in one module terminal portion 201 may each correspond to one of the terminal bus bars 133 and 134 included in the first battery cell assembly 121 and the second battery cell assembly 122. In this case, the terminal bus bars 133 and 134 of the first battery cell assembly 121 and the second battery cell assembly 122, respectively corresponding to the two terminal holes 202 of one module terminal portion 201, may have different polarities from each other.

[0084] More specifically, the negative electrode of the second battery cell assembly 122, the positive electrode of the first battery cell assembly 121, the positive electrode of the second battery cell assembly 122, and the negative electrode of the first battery cell assembly 121 can be arranged based on the stacking direction. In this way, in the dual structure according to the present embodiment, the terminal bus bars 133 and 134 of the two battery cell assemblies 120 can be arranged in the order of negative electrode, positive electrode, positive electrode and negative electrode. However, this is not always the case, and they can also be arranged in the order of positive electrode, negative electrode, negative electrode and positive electrode, and can also be arranged in a different order according to the design. In this regard, reference can be made to Fig.19 , which will be described later.

[0085] like Figure 8 As shown, the terminal bus bars 133 and 134 are installed with bus bar bolts 138, and the cell assembly 120 is inserted into the module housing 200, and then the position of the bus bar bolts 138 can be adjusted. Figure 2 The bus bar bolt 138 is connected to the terminal assembly 300 located outside the module housing 200 through the terminal hole 202, so that the battery cell assembly 120 (for example, the battery cell assembly 120 of the adjacent battery module 100) can be electrically connected to an external device. Meanwhile, in the case of the battery module 100 located at the outermost side of the battery pack 1000 (see Fig. 9 ), the two battery cell assemblies 120 included in one battery module 100 may be electrically connected through the terminal assembly 300 for HV connection. In addition, the battery module 100 located at the outermost side may be electrically connected to the BDU 190 through the terminal assembly 300 (see Fig.17 ).

[0086] Reference Figures 2 to 5, the battery module 100 according to the present embodiment includes a terminal assembly located at a portion overlapping with the area between the first submodule 100a and the second submodule 100b, and a portion overlapping with the module extension portion located at a portion where the first submodule 100a and the second submodule 100b face each other. A terminal assembly 300 may be provided to achieve HV connection with the battery module 100. The terminal assembly 300 may be located on the module terminal portion 201 of the module housing 200. The terminal assembly 300 is connected to the terminal bus bars 133 and 134 within the module housing 200, and thus may be electrically connected to the battery cell assembly 120.

[0087] Reference Figure 7 and Fig. 9 , the terminal assembly 300 can be electrically connected between adjacent battery modules 100. More specifically, the terminal assembly 300 is connected to the positive pole of the terminal bus bars 133 and 134 of one battery module 100, and can be connected to the negative pole of the terminal bus bars 133 and 134 of the battery module 100 adjacent to the above battery module 100. In addition, the terminal assembly 300 can electrically connect the BDU 190 and the battery module 100 adjacent thereto. In addition, depending on the position, the terminal assembly 300 can be configured to electrically connect the two battery cell assemblies 120 of the battery module 100 located at the outermost side.

[0088] Reference Figures 3 to 5 , the terminal assembly 300 according to the present embodiment may be connected to the terminal bus bar of each of the first submodule 100a and the second submodule 100b through the openings 211 and 215 formed in the portion of the module housing 200 overlapping the module extension portion. The bracket 220 may be located in the openings 211 and 215, and a sealing member may be formed between the bracket 220 and the terminal assembly 300. When an electrical connection structure is formed by a structure in which the terminal assembly 300 is connected to the bracket 220, the sealing member may ensure a sealing structure of the insulating oil for direct module cooling.

[0089] In addition, the terminal assembly 300 according to the present embodiment includes a connection cable 310 having a flexible characteristic, a terminal housing 320 connected to the connection cable 310, and an upper cover 330 covering the upper portion of the terminal housing 320 connected to the bracket 220. In addition, the terminal assembly 300 that connects terminal bus bars having different polarities from each other can electrically connect the adjacent first battery module and the second battery module. At this time, the first battery module and the second battery module are connected by Figure 5 The first terminal assembly 300 a and the second terminal assembly 300 b are shown to be electrically connected, and the first terminal assembly 300 a and the second terminal assembly 300 b may be connected to each other by a fixing member 350 .

[0090] The module housing 200 according to the present embodiment is formed of a high-rigidity material, and the high-rigidity material may include fiber reinforced plastic (FRP) as a composite material. Due to the high rigidity of the module housing 200, it can not only control the battery cells with high capacity and high expansion, but also the module housing 200 itself is used as a battery pack housing, so that the battery pack housing structure can be minimized and the long-term reliability of the seal is ensured. In addition, since the upper part of the module housing 200 is used as a battery pack cover, the upper housing can be omitted from the battery pack.

[0091] The module case 200 according to the present embodiment includes at least two plates spaced apart from each other, and a space may be formed between the plates. Such a space may be a space in which a coolant flows.

[0092] According to the present embodiment, the coolant used for cooling is a fluid, and the coolant can be in direct contact with the battery cell assembly 120, other electrical components, and the busbar frame 130 in the battery module 100. At this time, since the coolant must be electrically insulating, the coolant according to the present embodiment can be a material having insulating properties. As an example, the coolant can be insulating oil.

[0093] As described above, the coolant can directly contact the battery cell assembly 120, other electrical components, and the busbar frame 130 that generate heat in the battery module 100, thereby directly cooling the above components while receiving the transfer of heat. Therefore, compared with the traditional method of indirectly cooling the battery module using a radiator, the cooling efficiency can be improved, thereby extending the service life of the battery.

[0094] Fig. 9 is shown by connecting Figure 4 A perspective view of a battery pack formed by multiple battery modules. Fig.10 It is a front view of a state where adjacent battery modules are connected together.

[0095] Reference Fig. 9 According to the present embodiment, the battery pack 1000 includes a plurality of battery modules 100, a first battery module and a second battery module included in the plurality of battery modules 100 are adjacent to each other, and the first battery module 100a and the second battery module 100b may be electrically connected through a first terminal assembly 300a and a second terminal assembly 300b.

[0096] Reference Figure 5 As described above, the first terminal assembly 300 a and the second terminal assembly 300 b are connected to each other by the fixing member 350 , and the fixing member 350 may be fastened to the module housing 200 by the fastening member 360 .

[0097] In addition, refer to Figure 4 , Fig. 9 and Fig.10 , in a state where the flange portions 200F formed on the side surfaces of the module housing 200 overlap each other, the battery modules 100 adjacent to each other can be connected by a module fastening member 1200 such as a bolt. At this time, the flange portion 200F can be formed one by one on each of the upper and lower sides of the side surface of the module housing 200. Through this connection structure, the battery pack housing structure can be eliminated, the number of battery pack housing parts can be minimized, and specifically, the module fastening member 1200 can be connected at the overlapping portion of the flange portion 200F formed on the upper and lower sides of the side surface of the flange portion 200F, so that components such as rigid beams can be removed. In other words, the connection portion of the module fastening member 1200 included in the overlapping portion of the flange portion 200F can be used as a rigid beam in the battery pack structure. A plurality of module fastening members 1200 can be formed to be spaced apart from each other along the length direction (y-axis direction) of the battery module 100.

[0098] In addition, the battery pack 1000 according to the present embodiment includes a battery pack frame 1100 that protects a plurality of battery modules 100 from external impacts. The battery pack frame 1100 may include a front frame 1110, a rear frame 1120, a first side frame 1130, and a second side frame 1140. Among them, the front frame 1110 and the rear frame 1120 may extend in the length direction (y-axis direction) of the battery module 100, and the lengths of the front frame 1110 and the rear frame 1120 may be similar to the length of the battery module 100. The first side frame 1130 and the second side frame 1140 may extend in the width direction (x-axis direction) of the battery module 100. In addition, the lengths of the first side frame 1130 and the second side frame 1140 may be proportional to the number of battery modules 100 included in the battery pack 1000.

[0099] A plurality of battery modules 100 are aligned in one direction (x-axis direction), and adjacent battery modules 100 are connected to each other through flange portions 200F and module fastening members 1200, and then the front frame 1110 may be connected to the outermost battery module 100 through a separate fastening member. In addition, the rear frame 1120 may be connected to the other side of the BDU 190 through a separate fastening member after the outermost battery module 100 on the other side is connected to one side of the BDU 190. In addition, after the outermost battery module 100 on the other side is connected to one side of the BDU 190, the rear frame 1120 may be connected to the other side of the BDU 190 through a separate fastening member. Fig.13 After the cooling assembly 600 and the LV cable 800 are mounted on the front surface or the rear surface of the plurality of battery modules 100 , the first side frame 921 and the second side frame 922 may be coupled to cover the front surface or the rear surface of the plurality of battery modules 100 .

[0100] The overall structure of the battery pack frame 1100 according to the present embodiment may have a shape that exposes the upper and lower portions of the battery modules 100. In other words, the battery pack frame 1100 may not separately include an upper cover that covers the upper portions of the plurality of battery modules 100 and a lower cover that supports the lower portions of the plurality of battery modules 100. At this time, the upper and lower portions of the module housing formed of a highly rigid material may form the upper and lower covers of the battery pack frame 1100.

[0101] Therefore, the battery pack frame 1100 of the present embodiment covers the front and rear surfaces, or the left and right surfaces of the battery module assembly in which a plurality of battery modules 100 are aligned for structural stability of the battery pack 1000, but unlike conventional battery packs, the frame structure provided on the upper or lower surface may be removed, thereby providing the advantages of increased energy density and space efficiency.

[0102] Fig.11 is a perspective view illustrating coupling between a battery module and a cooling assembly according to an embodiment of the present disclosure. Fig.12 is a diagram illustrating a front surface or a rear surface of a battery module according to an embodiment of the present disclosure. Fig.13 and Fig.14 is a front view illustrating coupling of a cooling assembly in a battery pack according to an embodiment of the present disclosure. Fig.13 Is from Fig. 9 When the first side frame 1130 is removed, Fig. 9 The graph viewed from direction P in Fig.14 The second side frame 1140 is removed. Fig. 9 Figure viewed in the Q direction.

[0103] Reference Figures 11 to 14 , the battery pack 1000 of the present embodiment may include a cooling assembly 600 that provides a coolant into the battery module 100 .

[0104] The cooling assembly 600 may include a cooling pipe 610 for moving a coolant and a cooling port 620 for allowing the coolant to enter and exit. The cooling port 620 may be coupled to a cooling port opening 420 formed in the end plate 400, through which the coolant may be provided from the cooling pipe 610 to the interior of the battery module 100. The coolant introduced into the battery module 100 may cool the battery cells while in direct contact with the battery cells. Therefore, the direct cooling method of the present embodiment may significantly improve the cooling efficiency compared to the conventional indirect cooling method with the aid of a heat transfer member and a cooling fin.

[0105] The cooling port 620 may have holes on both sides for coupling with the end plate 400, and the cooling port fastening member 760 is inserted into the hole so that the cooling port 620 and the end plate 400 can be stably coupled. In order to prevent the coolant around the cooling port 620 from leaking, a sealing member such as an O-ring may be provided between the cooling port 620 and the end plate 400.

[0106] The cooling ports 620 connected to each battery module 100 may all be connected to one cooling pipe 610, but this is not always the case. Fig.13 and Fig.14 As shown, part of the cooling ports 620 are connected to one cooling pipe 610, and the other part may be connected to another cooling pipe 610. By changing the connection structure of the cooling pipe 610 in this way, the flow of the coolant may be changed, thereby optimizing the cooling efficiency.

[0107] Reference Fig. 9 and Figures 11 to 14 In the battery pack 1000 according to the present embodiment, a plurality of cooling pipes 610 may be formed at the upper end or the lower end of the front surface and the rear surface of the battery module 100. Fig.13 and Fig.14 In a battery module 100, if arranged with Fig. 9 The first cooling pipe 610 on the front surface of the battery module 100 adjacent to the first side frame 1130 is arranged at the lower end of the front surface of the battery module 100, and is arranged at the lower end of the front surface of the battery module 100. Fig. 9 The second cooling pipe 610 at the rear surface of the battery module 100 adjacent to the second side frame 1140 may be arranged at the upper end of the rear surface of the battery module 100. On the contrary, in one battery module 100, if the second cooling pipe 610 is arranged at the rear surface of the battery module 100 adjacent to the second side frame 1140 Fig. 9 The first cooling pipe 610 on the front surface of the battery module 100 adjacent to the first side frame 1130 is arranged at the upper end of the front surface of the battery module 100, and is arranged at the upper end of the front surface of the battery module 100. Fig. 9The second cooling pipe 610 at the rear surface of the battery module 100 adjacent to the second side frame 1140 may be arranged at the lower end of the rear surface of the battery module 100. At this time, the coolant of the cooling pipe 610 arranged at the lower end of the front surface or the rear surface of the battery module 100 corresponds to the case where the coolant is supplied to the inside of the battery module 100 through the cooling port 620 connected to the cooling pipe 610. The coolant of the cooling pipe 610 arranged at the upper end of the front surface or the rear surface of the battery module 100 corresponds to the case where the coolant inside the battery module 100 is supplied from the cooling port 620 connected to the cooling pipe 610. According to the present embodiment, the cooling pipe 610 used as the coolant inlet is arranged at the lower part of the battery module, and the cooling pipe 610 used as the coolant outlet may be arranged on the upper part of the battery module. At this time, the coolant flows into the battery module through the cooling port 620 connected to the cooling pipe 610 arranged at the lower portion of the battery module, and the coolant is discharged to the outside of the battery module through the cooling port 620 connected to the cooling pipe 610 arranged at the upper portion of the battery module, so that the insulating oil is evenly distributed in the battery module 100, which can minimize the cooling deviation between the battery cells.

[0108] Reference Fig.14 , a portion of the cooling pipe 610 according to the present embodiment may be configured such that one end of the cooling pipe 610 is connected to the cooling port 620 at the upper end of the battery module, and the other end of the cooling pipe 610 may be connected to the cooling port 620 at the lower end of the battery module adjacent to the battery module. At this time, the structure of the cooling pipe 610 may be a curved portion 612 having a curved shape, so that a configuration in which the cooling assemblies of adjacent battery modules are connected in series with each other can be achieved.

[0109] In order to ensure that the cooling pipe 610 according to the present embodiment is installed on the battery module 100, a snap-fit ​​portion 650 may be formed on the front surface and the rear surface of the battery module 100. The snap-fit ​​portions 650 may be formed on the front surface and the rear surface of the battery module 100, respectively, or may be formed one by one at the upper end and the lower end of one surface of the battery module 100. The cooling pipe 610 is connected to the cooling port 620, and the cooling port 620 may be connected to the end plate 400 via a cooling port fastening member 760. At this time, the snap-fit ​​portion 650 may be used as a structure to assist the cooling port fastening member 760, so that the cooling pipe 610 may be stably installed on the battery module 100.

[0110] The engaging portion 620 may have a concave shape so as to be engaged with the outer shape of the cooling pipe 610. The cooling pipe 610 may be formed of a flexible material, and the radius of the mounting portion of the engaging portion 650 where the cooling pipe 610 is located is formed to be smaller than the radius of the cooling pipe 610 so that the cooling pipe 610 can be mounted in the engaging portion 650. This is an example, and the radius of the mounting portion of the engaging portion 650 does not necessarily need to be smaller than the radius of the cooling pipe 610. The engaging portion 650 may be formed to surround a portion of the outer surface of the cooling pipe 610.

[0111] At the same time, if Fig.13 and Fig.14 As shown, the LV cable 800 of this embodiment can be provided for connection between battery modules 100. Fig.13 and Fig.14 As shown, the LV connection structure of the present embodiment can be made simpler than the conventional LV connection structure, thereby being able to improve space efficiency.

[0112] The end plate 400 according to the present embodiment seals the open surface of the module housing 200, thereby protecting the battery cell assembly 120 and the electrical components connected thereto from external physical impact. To this end, the end plate 400 may be made of a material having a predetermined strength. For example, the end plate 400 may include a metal such as aluminum.

[0113] The end plate 400 may be coupled to the module case 200 while covering the bus bar frame 130 located on one surface of the battery cell assembly 120. Each corner of the end plate 400 may be coupled to a corresponding corner of the module case 200 by welding or the like.

[0114] Two end plates 400 may be provided to seal the two open surfaces of the module housing 200. Among them, the end plate provided on the front surface of the module housing 200 and the end plate provided on the rear surface of the module housing 200 may have the same shape. This may be to simplify the process and minimize the cost by manufacturing the two parts constituting the battery module 100 in the same form.

[0115] In addition, the end plate 400 may have a vertically or horizontally symmetrical shape. Specifically, the end plate 400 may include a fracture opening 410, a cooling port opening 420, and a CMC opening 460, each of which may have a vertically symmetrical shape. In addition, the end plate 400 may include two fracture openings 410, and the two fracture openings 410 may be positioned to be horizontally symmetrical relative to a vertical bisector (or a vertical centerline). The end plate 400 may include two cooling port openings 420, and the two cooling port openings 420 may be positioned to be horizontally symmetrical relative to a vertical bisector (or a vertical centerline) of the end plate 400.

[0116] In other words, the end plate 400 may have a symmetrical shape with respect to a first center line, which may be a line that vertically divides the end plate 400. In addition, the end plate 400 may have a symmetrical shape with respect to a second center line, which may be a line that horizontally divides the end plate 400. At this time, the vertically and horizontally symmetrical shapes are based on the overall shape, and it may be determined that components located outside, such as the mounting portion 490, are not included.

[0117] The end plate 400 has a vertically or horizontally symmetrical structure as a whole in this way, so that even if the battery module 100 is arranged upside down (i.e., the battery module is turned upside down), it can be conveniently connected to an external device, and can achieve effects such as simplifying the process or reducing costs, and facilitating design.

[0118] Fig.15 is a schematic diagram showing a connection relationship of cooling components in a battery pack according to a comparative example. Fig.16 is a schematic diagram showing the connection relationship of cooling components in a battery pack according to an embodiment of the present disclosure.

[0119] Reference Fig.15 (a), in the coolant flow path where the coolant passes through the inside of the plurality of battery modules 30, the cooling components are connected in parallel so that the coolant inflow portion and the coolant discharge portion constituting the coolant flow path are arranged in parallel. In other words, the coolant flows into the plurality of battery modules 30 in a parallel structure, and the coolant passing through the plurality of battery modules 30 is discharged to the outside of the battery modules in a parallel structure. On the other hand, referring to Fig.15 (b), in the coolant flow path where the coolant passes through the inside of the plurality of battery modules 30, the cooling components are connected in series so that the coolant inflow portion and the coolant discharge portion constituting the coolant flow path are arranged in series. In other words, the coolant flows into the plurality of battery modules 30 in a series structure, and the coolant passing through the plurality of battery modules 30 is discharged to the outside of the battery modules in a series structure.

[0120] In accordance with Fig.15 In the battery pack of (a), the total flow rate can be increased and the temperature difference between the plurality of battery modules can be reduced. Fig.15 In the battery pack of (b), the total flow rate can be reduced and the temperature difference between the plurality of battery modules can be increased.

[0121] Reference Fig.16In the battery pack according to the present embodiment, in the coolant flow path in which the coolant passes through the inside of the plurality of battery modules 100, the coolant flow path is a flow path in which the plurality of battery modules 100 are connected in series. Specifically, in the coolant flow path, N battery modules (where N is a natural number of 2 or more) are connected in parallel, and in a state in which a plurality of module groups including the N battery modules connected in parallel are arranged, the module groups may have flow paths connected in series to each other.

[0122] Alternatively, each of the plurality of module groups includes an inflow portion for allowing coolant to flow into the battery module 100 and a discharge portion for allowing coolant to be discharged from the battery module 100, and the module groups may be arranged so that the inflow portion and the discharge portion of the module groups are alternately formed based on one side of the battery module 100.

[0123] As described above, according to the present embodiment, by configuring the series-parallel mixed coolant flow path, a coolant flow path having an optimum flow rate and temperature deviation can be formed.

[0124] Fig.17 and Fig.18 is a diagram illustrating coupling of a battery module and a pack frame according to an embodiment of the present disclosure.

[0125] like Fig.10 As shown, a frame fastening portion 230 may be formed on the side surface of the module housing to couple with the battery pack frame when the battery pack is assembled. The frame fastening portion 230 may correspond to one of the holes formed in the mounting portion 490 of the end plate, such as Fig.11 As shown, and may be fixed to the pack frame together when the mounting portion 490 is coupled with the pack frame.

[0126] Reference Fig. 9 , Fig.17 and Fig.18 , a mounting hole 900 is formed in the first side frame 1130 and the second side frame 1140, and the mounting hole 900 may be arranged to correspond to the hole formed in the mounting portion 490 of the end plate 400. At this time, the frame fastening member 1105 may be inserted through the holes formed in the mounting hole 900 and the mounting portion 490, so that the battery module 100 can be coupled to the first side frame 1130 or the second side frame 1140. In addition, the inserted frame fastening member 1105 may be inserted into Fig.10 The module housing 200 is shown in the frame fastening portion 230 , thereby further improving the structural stability.

[0127] Fig.19 is a plan view showing a structure of connecting terminal assemblies in a battery pack according to an embodiment of the present disclosure.

[0128] Reference Fig.19, a plurality of terminal assemblies 300 can electrically connect adjacent battery modules across the P region, thereby connecting the battery module to an external power source or BDU (battery disconnect unit) 190, so that an HV (high voltage) connection structure can be formed. The plurality of terminal assemblies can be located at a portion overlapping with a module extension portion in which a first submodule and a second submodule constituting one battery module face each other, and can extend parallel to the direction in which the battery cells are stacked.

[0129] As described above, in the battery pack 1000 according to the present embodiment, the connection between the plurality of battery modules 100 and between the battery module 100 and the BDU 190 is formed through the terminal assembly 300 on the upper side of the module housing, so that the HV connection structure can be relatively simplified and the margin of assembly tolerance can be ensured.

[0130] A conventional battery pack includes a battery module, a cooling structure such as a heat transfer pad and a heat sink, and a battery pack housing, wherein the battery pack housing includes many metal rows, including a battery pack cover, a battery pack frame, a crossbeam, and an underguard. In contrast, the battery pack of the present disclosure has a direct cooling structure through the circulation of insulating oil, has no separate cooling structure except for components for sealing, and can connect high-rigidity battery modules to form a battery pack, thereby minimizing the battery pack housing.

[0131] Although the present invention has been described in detail with reference to its preferred embodiments, the scope of the present disclosure is not limited thereto and those skilled in the art may make various modifications and improvements using the basic concepts of the present disclosure defined in the appended claims which also belong to the scope of the present disclosure.

[0132] [Explanation of Reference Numerals]

[0133] 100: Battery module

[0134] 120: Battery cell components

[0135] 130: Busbar frame

[0136] 200: Module housing

[0137] 200A: Open

[0138] 210: Cooling fin

[0139] 220: Bracket

[0140] 300: Terminal assembly

[0141] 310: Connecting cable

[0142] 320: Terminal housing

[0143] 330: Upper cover

[0144] 350: Fixed components

[0145] 360: Fastening components

Claims

1. A battery module, comprising: a first submodule and a second submodule, each of the first submodule and the second submodule comprising a battery cell assembly having a plurality of battery cells stacked thereon, and a bus bar electrically connecting the battery cells and a bus bar frame covering the battery cell assembly on at least one side; a module housing, the module housing accommodating the first submodule and the second submodule at the same time; as well as a terminal assembly located at a portion overlapping an area between the first submodule and the second submodule, wherein an opening is formed in a portion of the module housing, and the terminal assembly is connected to a terminal bus bar of each of the first submodule and the second submodule through the opening.

2. The battery module according to claim 1, further comprising: a bracket, the bracket being located in the opening; as well as A sealing member is formed between the bracket and the terminal assembly.

3. The battery module according to claim 2, wherein: The terminal assembly includes a connection cable having a flexible characteristic, a terminal housing coupled to the connection cable, and an upper cover covering an upper portion of the terminal housing connected to the bracket.

4. The battery module according to claim 1, wherein: The module housing is formed of a high-rigidity material, and The high-rigidity material includes fiber reinforced plastic (FRP) which is a composite material.

5. The battery module according to claim 1, further comprising: a flange portion formed on a side surface of the module housing; as well as A module fastening member is coupled to the flange portion.

6. A battery pack, comprising: A plurality of battery modules according to any one of claims 1 to 5, The first battery module and the second battery module included in the plurality of battery modules are adjacent to each other. The first battery module and the second battery module are electrically connected via a first terminal assembly and a second terminal assembly, and Wherein, the first terminal assembly and the second terminal assembly are connected to each other by a fixing member.

7. The battery pack according to claim 6, wherein: Respective flange portions of the first battery module and the second battery module overlap each other, and the first battery module and the second battery module are coupled by a module fastening member passing through the overlapping flange portions.

8. The battery pack according to claim 7, wherein: A coupling portion including the module fastening member forms a rigid beam of the battery pack.

9. The battery pack according to claim 6, wherein: The fixing member is fastened to the module case by a fastening member.

10. The battery pack according to claim 6, The battery pack further includes a battery pack frame surrounding the plurality of battery modules from the front side, the rear side, the left side, and the right side, respectively, wherein: The battery pack frame is divided into a plurality such that the plurality of battery modules correspond to the front side, the rear side, the left side, and the right side, respectively.

11. The battery pack according to claim 10, The battery pack further includes a frame fastening portion formed on a side surface of the module case, in, At least one of the battery pack frames is connected to the battery module by inserting a frame fastening member into the frame fastening portion.

12. The battery pack according to claim 11, wherein: forming a mounting hole in at least one of the battery pack frames, The mounting holes are arranged to correspond to holes formed in the mounting portions of the end plates of the battery modules, and The frame fastening member is inserted into the mounting hole and the hole formed in the mounting portion.

13. The battery pack according to claim 10, wherein: The overall structure of the pack frame has a shape in which upper and lower portions of the battery module are exposed.

14. The battery pack according to claim 13, wherein: The upper portion and the lower portion of the module case formed of a high-rigidity material form an upper cover and a lower cover of the pack frame.

15. The battery pack according to claim 6, wherein: The first terminal assembly and the second terminal assembly are respectively connected to terminal bus bars having polarities different from each other.

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