Battery module and battery pack including the battery module

Abstract

A battery module according to one embodiment of the present disclosure includes: a battery cell stack having a plurality of battery cells stacked thereon; a plate-shaped lower plate located below the battery cell stack; a module frame for covering an upper surface and both side surfaces of the battery cell stack; and a thermally conductive resin layer located between the lower plate and the battery cell stack.

Description

Technical Field

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims the benefit of Korean Patent Application No. 10-2020-0102355 filed on August 14, 2020, in the Korean Intellectual Property Office, the disclosure of which is incorporated herein by reference in its entirety.

[0003] The present disclosure relates to a battery module and a battery pack including the same, and more particularly, to a battery module capable of adjusting a usage amount of a thermally conductive resin and a battery pack including the same. Background Art

[0004] In modern society, with the daily use of portable devices such as mobile phones, laptops, camcorders, and digital cameras, the development of technology in the field related to the mobile devices as described above has been stimulated. In addition, rechargeable / dischargeable secondary batteries are used as power sources for electric vehicles (EVs), hybrid electric vehicles (HEVs), plug-in hybrid electric vehicles (P-HEVs), etc., in an attempt to solve the air pollution caused by existing gasoline vehicles using fossil fuels, etc. Therefore, the demand for the development of secondary batteries is increasing.

[0005] Currently available secondary batteries include nickel-cadmium batteries, nickel-metal hydride batteries, nickel-zinc batteries, lithium secondary batteries, etc. Among them, lithium secondary batteries have attracted much attention because they have advantages over nickel-based secondary batteries, for example, they hardly show a memory effect and are thus freely chargeable and dischargeable, have a very low self-discharge rate, and have a high energy density.

[0006] Such lithium secondary batteries mainly use lithium-based oxides and carbonaceous materials as positive electrode active materials and negative electrode active materials, respectively. The lithium secondary battery includes: an electrode assembly in which a positive electrode plate and a negative electrode plate coated with positive electrode active materials and negative electrode active materials, respectively, are arranged with a separator interposed therebetween; and a battery case that seals and contains the electrode assembly and an electrolyte.

[0007] Generally, lithium secondary batteries may be divided into can type secondary batteries in which an electrode assembly is mounted in a metal can, and pouch type secondary batteries in which an electrode assembly is mounted in a pouch of an aluminum laminate sheet, based on the shape of an exterior material.

[0008] In the case of a secondary battery for a small device, two to three battery cells are provided, but in the case of a secondary battery for a medium or large device such as an automobile, a battery module (Battery module) in which a large number of battery cells are electrically connected is used. In such a battery module, a large number of battery cells are connected in series or in parallel to each other to form a battery cell stack, thereby increasing capacity and output. In addition, one or more battery modules may be installed together with various control and protection systems such as a BMS (Battery Management System) and a cooling system to form a battery pack.

[0009] Figure 1 This is a perspective view of a conventional battery module. Figure 2 yes Figure 1 An exploded perspective view of a battery module.

[0010] Reference Figure 1 and Figure 2 , a conventional battery module 10 includes: a battery cell stack 20 formed by stacking battery cells; a cell frame 30 for accommodating the battery cell stack 20; and a thermally conductive resin layer 50 located between the battery cell stack 20 and the bottom surface of the cell frame 30. The cell frame 30 may be a metal plate material with the front and rear sides opened, and the end plate 70 may cover the open front and rear sides of the cell frame 30.

[0011] In addition, the conventional battery module 10 may further include an upper cover 41 and a bus bar frame 42 housed in the single body frame 30 together with the battery cell stack 20. The upper cover 41 is located at the upper portion of the battery cell stack 20, thereby preventing damage to the battery cell stack 20 when the battery cell stack 20 is inserted into the single body frame 30. The bus bar frame 42 may be located on the front and rear surfaces of the battery cell stack 20, respectively. Bus bars 43 connected to electrode leads of battery cells constituting the battery cell stack 20 may be mounted on the bus bar frame 42.

[0012] In addition, a thermally conductive resin may be injected between the battery cell stack 20 and the bottom surface of the single body frame 30 to form a thermally conductive resin layer 50, which can transfer the heat generated by the battery cell stack 20 to the bottom of the battery module 10. Figure 3 A method of forming the thermally conductive resin layer 50 in the conventional battery module 10 is described.

[0013] Figure 3 It is shown Figure 1 A perspective view of a battery module in a state where the bottom surface is turned upside down.

[0014] Reference Figures 1 to 3 An injection hole 30H for injecting a thermally conductive resin may be formed on the bottom surface of the conventional battery module 10 , that is, on the bottom surface of the cell frame 30 .

[0015] Specifically, the battery cell stack 20, the upper cover 41, the busbar frame 42, etc. are accommodated in the single body frame 30, and then the end plate 70 covers the open front and rear of the single body frame 30. At this time, the single body frame 30 and the end plate 70 can be joined to each other by a method such as welding. After that, a thermally conductive resin can be injected through the injection hole 30H to form a thermally conductive resin layer 50 between the battery cell stack 20 and the bottom surface of the single body frame 30.

[0016] However, the injection amount of the thermally conductive resin varies greatly because the injection is performed after first accommodating the battery cell stack 20. In addition, in the process of injecting the thermally conductive resin, due to gaps between components in the battery module, etc., more than a predetermined fixed amount may be injected, thereby increasing the production cost of the battery module, which may adversely affect profitability.

[0017] Furthermore, during the injection process, the battery cell stack 20 may be pushed toward the top surface of the cell frame 30 due to the pressure of the thermally conductive resin, which may affect the size of main components such as the terminal bus bar.

[0018] Furthermore, since injection is performed through the injection hole 30H, it is difficult for the thermally conductive resin layer 50 to form a constant thickness between the battery cell stack 20 and the bottom surface of the cell frame 30. This is the reason why the heat transfer performance of each region is different.

[0019] Therefore, it is necessary to develop a technology for a battery module that can appropriately adjust the amount of thermally conductive resin used. Summary of the invention

[0020] Technical issues

[0021] An object of the present disclosure is to provide a battery module having a new structure capable of injecting an appropriate amount of thermally conductive resin and a battery pack including the battery module.

[0022] However, the problems to be solved by the embodiments of the present disclosure are not limited to the above-mentioned problems, and various extensions can be made within the scope of the technical concept included in the present disclosure.

[0023] Technical Solution

[0024] According to one embodiment of the present disclosure, a battery module is provided, comprising: a battery cell stack having a plurality of battery cells stacked thereon; a plate-shaped lower plate located below the battery cell stack; a module frame for covering an upper surface and two side surfaces of the battery cell stack; and a thermally conductive resin layer located between the lower plate and the battery cell stack.

[0025] The module frame may include: a first side surface portion and a second side surface portion covering the two side surfaces of the battery cell stack; and a top portion covering the upper surface of the battery cell stack.

[0026] The first side surface portion, the second side surface portion, and the top portion may be integrally formed.

[0027] A first edge portion and a second edge portion of the lower plate facing each other may be joined to the first side surface portion and the second side surface portion, respectively.

[0028] The first edge portion and the second edge portion may be weld-joined to the first side surface portion and the second side surface portion, respectively.

[0029] The lower plate may include a mounting portion, and the mounting portion may be formed on first and second edge portions of the lower plate facing each other.

[0030] A mounting hole may be formed in the mounting portion, and the mounting portion may extend parallel to one surface of the lower plate.

[0031] The thermally conductive resin layer may be formed by applying thermally conductive resin to the lower plate.

[0032] The battery module may further include a compression pad surrounding the thermally conductive resin layer.

[0033] The battery cell may include electrode leads protruding in opposite directions and a protrusion formed on one edge of the battery cell. The protrusion may be located closer to one end of the lower plate in a direction in which one of the electrode leads protrudes than the compression pad.

[0034] The lower plate may include a step portion formed at the one end portion of the lower plate, and the protrusion may be located above the step portion.

[0035] The thickness of the thermally conductive resin layer may be equal to or thinner than the thickness of the compression pad portion.

[0036] The thermally conductive resin layer may include a first thermally conductive resin layer and a second thermally conductive resin layer disposed to be spaced apart from each other.

[0037] The battery module may further include a first compression pad surrounding the first thermally conductive resin layer and a second compression pad surrounding the second thermally conductive resin layer.

[0038] According to another embodiment of the present disclosure, a battery pack including the battery module is provided.

[0039] Beneficial Effects

[0040] According to an embodiment of the present disclosure, applying an appropriate amount of thermally conductive resin may be achieved through the structure of the plate-shaped lower plate and the module frame.

[0041] Furthermore, by adjusting the amount of application of the thermally conductive resin and controlling the thickness of the compression pad, the dimensional stability of the battery module in the height direction can be easily ensured.

[0042] Furthermore, the mounting structure is applied to the lower plate in a plate shape, thereby enabling free design and simplification of shape.

[0043] The effects of the present disclosure are not limited to the above-described effects, and additional other effects not described above will be clearly understood by those skilled in the art from the description of the appended claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Figure 1 is a perspective view of a conventional battery module;

[0045] Figure 2 yes Figure 1 An exploded perspective view of a battery module;

[0046] Figure 3 It is shown Figure 1 A perspective view of a battery module in which the bottom surface is turned upside down;

[0047] Figure 4 is a perspective view of a battery module according to an embodiment of the present disclosure;

[0048] Figure 5 The end plate is removed Figure 4 An exploded perspective view of a battery module;

[0049] Figure 6 It is shown Figure 5 An exploded perspective view of a battery cell stack, a bus bar frame, and a bus bar included in a battery module;

[0050] Figure 7 yes Figure 6 A perspective view of a battery cell included in a battery cell stack;

[0051] Figure 8 is a perspective view of a module frame according to a comparative example of the present disclosure;

[0052] Fig. 9 is a perspective view of a lower plate according to an embodiment of the present disclosure;

[0053] Fig.10 When viewed along the -x axis in the yz plane Figure 4 A front view of a battery module;

[0054] Fig.11 is a perspective view showing a battery cell stack and a lower plate according to an embodiment of the present disclosure;

[0055] Fig.12 (a) is along Fig.11 A cross-sectional view taken along the cutting line A-A';

[0056] Fig.12 (b) is along Fig.11 A cross-sectional view taken along the cutting line BB';

[0057] Fig.13 is a perspective view showing a lower plate according to a modified embodiment of the present disclosure;

[0058] Fig.14 (a) is along Fig.13 A cross-sectional view taken along the cutting line C-C';

[0059] Fig.14 (b) is along Fig.13 Cross-sectional view taken along the cutting line D-D'. DETAILED DESCRIPTION

[0060] 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 them. The present disclosure can be modified in various different ways and is not limited to the embodiments set forth herein.

[0061] For clarity, description of parts not related to the description will be omitted herein, and like reference numerals denote like elements throughout the application.

[0062] In addition, in the drawings, for the convenience of description, the size and thickness of each element are arbitrarily shown, and the present disclosure is not necessarily limited to those shown in the drawings. In the drawings, for the sake of clarity, the thickness of layers, regions, etc. are exaggerated. In the drawings, for the convenience of description, the thickness of some layers and regions is exaggeratedly shown.

[0063] Furthermore, it will be understood that when an element such as a layer, film, region, or plate is referred to as being "on" or "over" another element, the element may be directly on the other element or intervening elements may also be present. Conversely, when an element is referred to as being "directly on" another element, this means that no other intervening elements are present. Furthermore, the term "on..." or "over..." refers to being disposed above or below a reference portion, and does not necessarily mean being disposed "on" or "over" a reference portion in the opposite direction of gravity.

[0064] Furthermore, throughout the application, when a part is referred to as “comprising” a certain component, it means that the part may further include other components, without excluding the other components, unless otherwise specified.

[0065] Furthermore, throughout the application, when referred to as a “plane”, it means when the target portion is viewed from the upper side, and when referred to as a “section”, it means when the target portion is viewed from the side of a vertically cut cross section.

[0066] Figure 4 is a perspective view of a battery module according to an embodiment of the present disclosure. Figure 5 The end plate is removed Figure 4 An exploded perspective view of a battery module. Figure 6 It is shown Figure 5 An exploded perspective view of a battery cell stack, a bus bar frame, and bus bars included in a battery module. Figure 7 yes Figure 6 A perspective view of a battery cell included in a battery cell stack.

[0067] Reference Figures 4 to 6 , the battery module 100 according to the embodiment of the present disclosure includes: a battery cell stack 200 on which a plurality of battery cells 110 are stacked; a plate-shaped lower plate 300 located below the battery cell stack 200; a module frame 400 for covering the upper surface and both side surfaces of the battery cell stack 200; and a thermally conductive resin layer 500 located between the lower plate 300 and the battery cell stack 200. In addition, the battery module 100 may further include end plates 700 located on the front and rear surfaces of the battery cell stack 200, respectively, and an insulating cover (not shown) having electrical insulation may be provided between the battery cell stack 200 and the end plates 700.

[0068] First, the battery cell 110 is preferably a pouch-type battery cell and may be formed in a rectangular sheet structure. For example, the battery cell 110 according to the present embodiment has a structure in which two electrode leads 111 and 112 face each other and protrude from one end and the other end, respectively.

[0069] In particular, refer to Figure 7The battery cell 110 according to the present embodiment has a structure in which two electrode leads 111 and 112 are opposite to each other and protrude from one end 114a and the other end 114b of the cell body 113, respectively. More specifically, the electrode leads 111 and 112 are connected to an electrode assembly (not shown) and protrude from the electrode assembly (not shown) to the outside of the battery cell 110.

[0070] In addition, the battery cell 110 may be manufactured by joining the two end portions 114a and 114b of the unit case 114 and one side portion 114c connecting the two end portions 114a and 114b in a state where the electrode assembly (not shown) is accommodated in the unit case 114. In other words, the battery cell 110 according to the present embodiment has a total of three sealing portions 114sa, 114sb, 114sc having a structure sealed by a method such as thermal fusion, and the remaining other side portion may be composed of a connection portion 115. The unit case 114 may be composed of a laminate sheet including a resin layer and a metal layer.

[0071] In addition, the connection portion 115 may extend elongatedly along one edge of the battery cell 110, and a protrusion 110p of the battery cell 110 called a bat-ear may be formed at the end of the connection portion 115. However, the protrusion 110p is an exemplary structure, and the battery cell 110 according to another embodiment of the present disclosure may have a form in which the protrusion is not formed and the connection portion 115 extends in a straight line.

[0072] The battery cell 110 may be configured in plural, and the plural battery cells 110 may be stacked to be electrically connected to each other, thereby forming a battery cell stack 200. In particular, as Figure 6 As shown in , a plurality of battery cells 110 may be stacked along the y-axis direction. Therefore, one electrode lead 111 of the battery cell 110 may protrude toward the x-axis direction, and the other electrode lead 112 may protrude toward the -x-axis direction.

[0073] The lower plate 300 is a plate-shaped member, and the battery cell stack 200 can be placed on the lower plate 300. The module frame 400 may include: a first side surface portion 410 and a second side surface portion 420 covering the two side surfaces (y-axis direction and -y-axis direction) of the battery cell stack 200; and a top 430 covering the upper surface (z-axis direction) of the battery cell stack 200. Specifically, the first side surface portion 410 and the second side surface portion 420 may extend downward from both ends of the top 430. In addition, the first side surface portion 410, the second side surface portion 420 and the top 430 may be formed integrally. The module frame 400 may form an n-shaped cross section cut along the yz plane.

[0074] The lower plate 300 and the module frame 400 may be joined by welding or the like in a state where the corresponding corners are in contact with each other, thereby forming a structure that vertically and horizontally covers the battery cell stack 200. Specifically, the first edge portion 310 and the second edge portion 320 of the lower plate 300 facing each other may be butt-joined with the first side surface portion 410 and the second side surface portion 420, respectively. The connection method is not particularly limited, but it is preferred that the first edge portion 310 and the second edge portion 320 are welded and joined to the first side surface portion 410 and the second side surface portion 420, respectively.

[0075] The battery cell stack 200 may be physically protected by the lower plate 300 and the module frame 400. To this end, the lower plate 300 and the module frame 400 may include a metal material having a predetermined strength.

[0076] When the battery cell stack 200 is accommodated in the lower plate 300 and the module frame 400, the end plate 700 may be provided on the open front surface (x-axis direction) and rear surface (-x-axis direction) of the battery cell stack 200. That is, the end plate 700 may be formed to be located on the front surface (x-axis direction) and rear surface (-x-axis direction) of the battery cell stack 200 and to cover the battery cell stack 200. The end plate 700 may be joined to the lower plate 300 and the module frame 400 by a method such as welding.

[0077] The thermally conductive resin layer 500 may be formed by applying thermally conductive resin to the lower plate 300. Specifically, the thermally conductive resin may be applied on the lower plate 300, the battery cell stack 200 may be disposed thereon, and then the thermally conductive resin may be cured to form the thermally conductive resin layer 500.

[0078] The thermally conductive resin may include a thermally conductive adhesive material, specifically, may include at least one of a silicone material, a polyurethane material, and an acrylic material. The thermally conductive resin is liquid during application, but solidifies after application, so that it can play a role in fixing the plurality of battery cells 110 constituting the battery cell stack 200. In addition, since the thermally conductive resin has excellent heat transfer characteristics, the heat generated from the battery module 110 can be quickly transferred to the lower side of the battery module 100, thereby preventing the battery module 100 from overheating. The heat generated from the battery cell 110 can be transferred to the outside of the battery module 100 via the thermally conductive resin layer 500, the lower plate 300, and the heat sink (not shown).

[0079] In addition, the thermally conductive resin layer 500 may include a first thermally conductive resin layer 510 and a second thermally conductive resin layer 520 that are spaced apart from each other. Specifically, the first thermally conductive resin layer 510 and the second thermally conductive resin layer 520 may be spaced apart from each other along a direction in which the electrode leads 111 and 112 protrude from the battery cell 110. Here, the direction in which the electrode leads 111 and 112 protrude from the battery cell 110 may correspond to the x-axis direction or the -x-axis direction.

[0080] When charging and discharging of the battery cell are repeatedly performed, a large amount of heat is generated in the portion close to the electrode leads 111 and 112. The thermally conductive resin layer 500 according to the present embodiment is not formed on the entire lower plate 300, but may be composed of a first thermally conductive resin layer 510 and a second thermally conductive resin layer 520 to correspond to the portion of the battery cell 110 where excessive heat is generated. Through this structure, the cooling and heat dissipation performance can be improved while saving raw materials.

[0081] In addition, for the battery cell 110 having a large difference in the degree of heat generation of each part, it is difficult for the thermally conductive resin layer formed on the entire lower plate 300 to eliminate the temperature deviation between the parts of the battery cell 110. In contrast, since the battery module 100 according to the present embodiment has the first thermally conductive resin layer 510 and the second thermally conductive resin layer 520, heat can be effectively dissipated at both ends of the battery cell 110 where excessive heat is generated, and the temperature deviation between the parts of one battery cell 110 can be minimized. Since the temperature deviation between the parts of the battery cell 110 eventually leads to a decrease in the performance of the battery module 100, the first thermally conductive resin layer 510 and the second thermally conductive resin layer 520 according to the present embodiment can help improve the performance and life of the battery module.

[0082] At this time, refer again Figures 1 to 3 In the conventional battery module 10, the thermally conductive resin is injected through the injection hole 30H to form the thermally conductive resin layer 50 between the battery cell stack 20 and the bottom surface of the single body frame 30, so it is difficult to accurately form the thermally conductive resin layer 50. Specifically, due to the gap between the components in the battery module, the thermally conductive resin exceeding a predetermined amount may be over-injected. In addition, by such an injection method, it is difficult to form the first thermally conductive resin layer 510 and the second thermally conductive resin layer 520 separated from each other as in the present embodiment.

[0083] Unlike this, since the thermally conductive resin layer 500 according to the present embodiment is formed by applying a thermally conductive resin on the lower plate 300, the possibility of excessive use of the thermally conductive resin is low. In addition, it has an advantage that the thermally conductive resin layer can be freely designed and configured as in the first thermally conductive resin layer 510 and the second thermally conductive resin layer 520. In addition, since it is not an injection method, it is conducive to uniformly forming the thickness of the thermally conductive resin layer 500. In addition, since the lower plate 300 is formed in a plate shape, it is easy to uniformly apply the thermally conductive resin to its edge portion.

[0084] In addition, although not specifically shown in the drawings, an insulating film or the like may be provided on the lower plate 300 between the first thermally conductive resin layer 510 and the second thermally conductive resin layer 520 .

[0085] Next, we will refer to Figure 8 etc. describe advantages of the lower plate 300 and the module frame 400 according to the present embodiment.

[0086] Figure 8 is a perspective view of a module frame according to a comparative example of the present disclosure.

[0087] Reference Figure 8 , a modular frame structure in which an upper frame 40a and a lower frame 40b are combined can be proposed as a comparative example of the present disclosure. Both the upper frame 40a and the lower frame 40b can have side wall portions, wherein the cross-section of the upper frame 40a can form an n-shape, and the cross-section of the lower frame 40b can form a u-shape. As described above, since the lower plate 300 according to the present embodiment is configured in a plate shape, it is easy to evenly apply the thermally conductive resin to the edge portion. On the other hand, since the lower frame 40b according to the comparative example has two side wall portions facing upward, such side wall portions may become an interference factor in the process of applying the thermally conductive resin.

[0088] Furthermore, when the upper frame 40a and the lower frame 40b are joined by a method such as welding, the joining portion is located at the center of the side surface. In such joining, the thickness, verticality, width between the side wall portions, etc. of the frame must be accurately controlled without error so that the side wall portions of the upper frame 40a and the side wall portions of the lower frame 40b can contact each other. Otherwise, the side wall portions of the upper frame 40a and the side wall portions of the lower frame 40b are not in contact with each other and are thus likely to be misaligned. In order to prevent such misalignment, the thickness of the upper frame 40a and the lower frame 40b must be increased, which is disadvantageous in terms of the space efficiency or battery capacity of the battery module. On the other hand, if Figure 5As shown in FIG. 1 , the first side surface portion 410 and the second side surface portion 420 of the module frame 400 according to the present embodiment facilitate docking with the lower plate 300 formed in a plate shape as a wide support structure. In addition, the risk of misalignment relative to the plate-shaped lower plate 300 is low, and thus the thickness of the module frame 400 can be formed thinner, which is advantageous in terms of space efficiency or battery capacity of the battery module.

[0089] Furthermore, if the joint portion between the upper frame 40a and the lower frame 40b is located at the center of the side surface, the internal battery cells and the like may be damaged due to penetration of the laser when performing laser welding and the like. On the other hand, according to the present embodiment, since the first edge portion 310 and the second edge portion 320 of the lower plate 300 are welded and joined to the first side surface portion 410 and the second side surface portion 420, respectively, welding can be performed without being penetrated by the laser.

[0090] Next, we will refer to Fig. 9 etc. describe the mounting portion according to an embodiment of the present disclosure.

[0091] Fig. 9 is a perspective view of a lower plate according to an embodiment of the present disclosure. Figure 5 The battery module includes a lower plate.

[0092] Reference Figure 5 and Fig. 9 , the lower plate 300 according to the present embodiment may include a mounting portion 300M, and such mounting portions 300M may be formed on the first edge portion 310 and the second edge portion 320 facing each other of the lower plate 300. The number of mounting portions 300M is not particularly limited, and as shown in the figure, a plurality of mounting portions 300M may be configured for each of the first edge portion 310 and the second edge portion 320.

[0093] A plurality of battery modules 100 according to the present embodiment may be assembled to form a battery pack, and each battery module 100 may be fixed to a structure such as a battery pack frame (not shown) of the battery pack via a mounting portion 300M. Specifically, a mounting hole 300H is formed in the mounting portion 300M, and the mounting portion 300M may extend parallel to one surface of the lower plate 300. A fastening structure such as a bolt and a nut is applied between the mounting hole 300H and the battery pack frame so that the battery module 100 can be fixed to the battery pack frame.

[0094] Refer again Figure 1 and Figure 2In the case of the conventional battery module 10, it is difficult to set the mounting portion 70M and the mounting hole 70H to the monomer frame 30, etc., so that the mounting portion 70M can only be formed on the end plate 70. The lower plate 300 of the plate-shaped structure according to the present embodiment can form the mounting portion 300M only by cutting from the plate material used as the base material, but in order to form the mounting portion 70M on the monomer frame 30, etc., it is inevitable to need complicated processes such as bending, additional molding or joining. Thus, in the conventional battery module 10, the mounting portion 70M is usually formed on the end plate 70 instead of on the monomer frame 30, etc. After all, the conventional mounting portion 70M is formed only in the two end portions of the end plate 70, that is, only in the restricted portions called the four corners relative to the battery module 10, and its number is also inevitably limited. In contrast, the lower plate 300 of the plate shape according to the present embodiment is easy to form the mounting portion 300M, and the position or number of the mounting portion 300M can be set more freely. As an example, the number of mounting portions 300M may be increased, thereby improving the degree of fixation of the battery module 100. In the design of the battery module 100 and the battery pack including the same, the position of the mounting portion 300M may be adjusted to reduce restrictions. In addition, the shape of the end plate 700 may be simplified and freely designed.

[0095] Next, we will refer to Fig. 9 etc. describe a compression pad portion according to an embodiment of the present disclosure.

[0096] The battery module 100 according to an embodiment of the present disclosure may further include a compression pad 600 surrounding the thermally conductive resin layer 500. Specifically, a first compression pad 610 surrounding the first thermally conductive resin layer 510 and a second compression pad 620 surrounding the second thermally conductive resin layer 520 may be provided. More specifically, the first compression pad 610 may be provided on the lower plate 300 to surround four sides of the first thermally conductive resin layer 510, and the second compression pad 620 may be provided to surround four sides of the second thermally conductive resin layer 520.

[0097] The compression pad part 600 including the first compression pad part 610 and the second compression pad part 620 may be a foam type pad including polyurethane (PU).

[0098] The positions of the first compression pad 610 and the second compression pad 620 are adjusted in advance to set an area, and a thermally conductive resin can be applied to the area to form the first thermally conductive resin layer 510 and the second thermally conductive resin layer 520. The positions of the first compression pad 610 and the second compression pad 620 can be freely set, so that the lateral length or the longitudinal length of each of the first thermally conductive resin layer 510 and the second thermally conductive resin layer 520 can be easily adjusted. In other words, the first compression pad 610 and the second compression pad 620 according to the present embodiment can serve as a kind of guide member for adjusting the area to which the thermally conductive resin is applied. That is, since the first compression pad 610 and the second compression pad 620 are set in advance, the thermally conductive resin can be prevented from being applied outside the predetermined area, so that the thermally conductive resin layer 500 can be accurately implemented in the desired area.

[0099] In addition, since the first compression pad 610 and the second compression pad 620 have a predetermined height, the injection amount of the thermally conductive resin can be prevented from overflowing. In particular, in the lower plate 300 of the plate-shaped structure, the first compression pad 610 and the second compression pad 620 can prevent the thermally conductive resin from flowing beyond the first edge portion 310 or the second edge portion 320.

[0100] In addition, the first compression pad 610 and the second compression pad 620 include materials to be compressed. Thus, when the battery cell stack 200 is placed thereon, it can be compressed. This can help the battery cell stack 200 to be attached to the first thermally conductive resin layer 510 and the second thermally conductive resin layer 520, which can ultimately lead to an improvement in the fixing force to the battery cell 110 or an improvement in the heat transfer performance via the thermally conductive resin layer 500.

[0101] Next, we will refer to Fig.10 etc. describe the advantage of dimensional stability of the battery module 100 according to an embodiment of the present disclosure.

[0102] First, refer again Figures 4 to 6 , the battery module 100 according to the present embodiment may further include a bus bar frame 800 on which the bus bar 810 and the terminal bus bar 820 are mounted.

[0103] The busbar 810 and the terminal busbar 820 may be bonded to the electrode leads 111 and 112 of the battery cell 110 so as to electrically connect the plurality of battery cells 110. Specifically, the busbar frame 800 on which the busbar 810 and the terminal busbar 820 are mounted may be disposed on the front surface (x-axis direction) and the rear surface (-x-axis direction) of the battery cell stack 200. The front surface (x-axis direction) and the rear surface (-x-axis direction) of the battery cell stack 200 correspond to the surfaces in the direction in which the electrode leads 111 and 112 of the battery cell 110 protrude. A lead groove may be formed in the busbar frame 800, and the electrode leads 111 and 112 are bent and bonded to the busbar 810 or the terminal busbar 820 after passing through the lead groove. The bonding method is not particularly limited as long as physical and electrical connection can be performed, for example, welding bonding may be performed.

[0104] In addition, a groove may be formed in the bus bar 810 or the terminal bus bar 820 and may be disposed corresponding to the lead groove of the bus bar frame 800. The electrode leads 111 and 112 passing through the lead groove may be bent via the groove of the bus bar 810 or the groove of the terminal bus bar 820.

[0105] In addition, a portion of the terminal bus bar 820 may be exposed to the outside of the battery module 100. Specifically, an opening portion may be formed in the end plate 700 or the insulation cover (not shown) so that a portion of the terminal bus bar 820 may be exposed. Figure 4 As shown in . A portion of the exposed terminal bus bar 820 may be connected to another battery module or a battery disconnect unit (BDU) to achieve a high voltage (HV) connection, etc. Here, the HV connection is a connection that functions as a power source for power supply, and the HV connection refers to a connection between battery cells or a connection between battery modules.

[0106] Fig.10 When viewed along the -x axis in the yz plane Figure 4 Front view of the battery module.

[0107] Reference Figure 4 and Fig.10 The battery module 100 according to the present embodiment can ensure the stability of the height direction dimension by adjusting the application amount of the thermally conductive resin and controlling the thickness of the compression pad part 600 .

[0108] exist Figures 1 to 3In the case of the conventional battery module 10 shown in , during the injection process, the battery cell stack 20 may be pushed toward the top surface of the single body frame 30 due to the pressure of the thermally conductive resin, thereby affecting the size of the main parts such as the terminal bus bar. When such a battery module 10 is configured in plurality and assembled into a battery pack, the battery modules 10 are connected to each other via the terminal bus bar. At this time, if the deviation of the height direction dimension of the terminal bus bar of each battery module 10 is large, there is a problem that heat is generated due to the increase in contact resistance or the voltage value becomes inaccurate.

[0109] On the other hand, in the battery module 100 according to the present embodiment, since the thermally conductive resin is applied to the lower plate 300 as described above, a thermally conductive resin layer 500 having a relatively constant thickness can be formed, and the battery cell stack 200 will not be pushed. In addition, the thickness and compression degree of the compression pad 600 can be calculated to ensure the dimensional safety of the battery module 100 in the height direction. As an example of the height direction dimension, the height direction dimension h of the terminal bus bar 820 can be considered. Considering the thickness of the thermally conductive resin layer 500 (corresponding to the amount of thermally conductive resin applied), the thickness of the compression pad 600, and the degree of compression of the compression pad 600, the height direction dimension h of the terminal bus bar 820 can be predicted for each battery module 100, and the height direction dimension h of such a terminal bus bar 820 can be stabilized, thereby showing a constant value. In other words, the battery module 100 according to the present embodiment can be easily stabilized by the method of applying the thermally conductive resin, the thickness control of the compression pad, etc., so that the height direction dimension h of the terminal bus bar of each product shows a constant value.

[0110] Furthermore, since the configuration of the lower plate 300 is also formed of a plate-shaped structure, processing of the bottom portion, which is a datum of the battery module 100 , is minimized, which may help ensure dimensional stability in a height direction.

[0111] Fig.11 is a perspective view showing a battery cell stack and a lower plate according to an embodiment of the present disclosure. Fig.12 (a) is along Fig.11 Cross-sectional view taken along the cutting line AA'. Fig.12 (b) is along Fig.11 The cross-sectional view taken along the cutting line BB'. At this time, Fig.12 (a) and Fig.12 (b) shows a state where the battery cell stack is placed on the lower plate.

[0112] Reference Figure 7 , Fig.11 , Fig.12 (a) and Fig.12(b), as described above, a protrusion 110p called a bat-ear may be formed in the battery cell 110 according to the present embodiment. Specifically, two protrusions 110p may be formed at both ends of the connection portion 115 in a direction in which the electrode leads 111 and 112 protrude.

[0113] When the battery cell stack 200 stacked with a plurality of battery cells 110 is placed on the compression pad 600 and the thermally conductive resin layer 500, the protrusion 110p may be located outside the compression pad 600. That is, the protrusion 110p is positioned closer to one end of the lower plate 300 than the compression pad 600, so that the compression pad 600 may be provided between the protrusion 110p and the thermally conductive resin layer 500. Specifically, any one of the protrusions 110p may be positioned closer to one end of the lower plate in the direction in which the electrode lead 111 protrudes than the first compression pad 610. The other protrusion 110p may be positioned closer to the other end of the lower plate in the direction in which the electrode lead 112 protrudes than the second compression pad 620. Here, the two ends of the lower plate 300 may refer to the ends in contact with the first edge portion 310 and the second edge portion 320.

[0114] Since the protrusion 110p of the battery cell 110 has a protruding shape, there may be a problem that the portion is damaged when the battery cell stack is placed. At this time, the compression pad 600 according to the present embodiment is located on the lower plate 300, so that a space in which the protrusion 110p of the battery cell 110 can be placed can be naturally provided. Therefore, problems such as damage to the battery cell 110 including the protrusion 110p when the battery cell stack 200 is placed can be prevented. For this purpose, the thickness t31 and t32 of the compression pad 600 according to the present embodiment may be thicker than the protruding thickness t1 of the protrusion 110p. Specifically, the thickness t31 of the first compression pad 610 and the thickness t32 of the second compression pad 620 may be thicker than the protruding thickness t1 of the protrusion 110p. Here, the protruding thickness t1 of the protrusion 10p may represent the length of the protrusion 110p protruding from the connecting portion 115 of the battery cell 110.

[0115] Fig.13 is a perspective view showing a lower plate 300 a according to a modified embodiment of the present disclosure. Fig.14 (a) is along Fig.13 The cross-sectional view taken along the cutting line C-C', Fig.14 (b) is along Fig.13 The cross-sectional view taken along the cutting line D-D'. At this time, Fig.14 (a) and Fig.14 (b) shows a state where the battery cell stack is placed on the lower plate.

[0116] Reference Figure 7, Fig.13 , Fig.14 (a) and Fig.14 (b), the lower plate 300a according to the modified embodiment of the present disclosure may include step portions 300S formed at both ends. Specifically, the step portions 300S may be formed at both ends of the lower plate 300a in the two directions in which the electrode leads 111 and 112 of the battery cell 110 protrude. Here, the step portion 300S may refer to a portion of the lower plate 300a that is thinner than other portions. Here, the two ends of the lower plate 300a may refer to the ends that are in contact with the first edge portion 310 and the second edge portion 320.

[0117] When the battery cell stack 200 stacked with a plurality of battery cells 110 is placed on the compression pad 600 and the thermally conductive resin layer 500, the protrusion 110p may be located on the step portion 300S. Specifically, the protrusion 110p located outside the compression pad 600 may be located above the step portion 300S and spaced apart from the step portion 300S. Any one of the protrusions 110p may be located on any one of the step portions 300S, and another one of the protrusions 110p may be located on another one of the step portions 300S.

[0118] Since the step portion 300S is formed on the lower plate 300a according to the present embodiment, the thicknesses t31 and t32 of the compression pad portion 600 may be thinner than the protruding thickness t1 of the protruding portion 110p. That is, the thickness t31 of the first compression pad portion 610 and the thickness t32 of the second compression pad portion 620 may be thinner than the protruding thickness t1 of the protruding portion 110p. By providing the step portion 300S, even if the thicknesses t31 and t32 of the compression pad portion 600 and the thicknesses t21 and t22 of the thermally conductive resin layer 500 are formed thinly, a space in which the protruding portion 110p of the battery cell 110 can be placed can be provided. The step depth of the step portion 300S may be set in consideration of the thicknesses t31 and t32 of the compression pad portion 600, the thicknesses t21 and t22 of the thermally conductive resin layer 500, and the protruding thickness t1 of the protruding portion 110p. Here, the step depth may refer to a difference between the thickness of the step portion 300S and the thickness of the remaining lower plate 300 a where the step portion 300S is not formed.

[0119] In addition, return to reference Fig.12 (a) Fig.12 (b) Fig.14 (a) and Fig.14 (b), the thicknesses t21 and t22 of the thermally conductive resin layer 500 are equal to or thinner than the thicknesses t31 and t32 of the compression pad portion 600. Specifically, the thickness t21 of the first thermally conductive resin layer 510 may be equal to or thinner than the thickness t31 of the first compression pad portion 610, and the thickness t22 of the second thermally conductive resin layer 520 may be equal to or thinner than the thickness t32 of the second compression pad portion 620.

[0120] As described above, the first compression pad 610 and the second compression pad 620 may prevent the injection amount of the thermally conductive resin from overflowing and may be compressed according to the placement of the battery cell stack 200. That is, the thicknesses t21 and t22 of the thermally conductive resin layer 500 may be equal to or thinner than the thicknesses t31 and t32 of the compression pad 600, wherein the compression pad 600 may be compressed due to the battery cell stack 200, and the battery cell stack 200 may be in close contact with the thermally conductive resin layer 500.

[0121] Although terms indicating directions such as up, down, left, right, front and rear directions are used in this embodiment, it will be apparent to those skilled in the art that these terms are for ease of description and merely indicate relative positions and may change depending on the position of the observer, the position of the object, etc.

[0122] One or more battery modules according to the present embodiment described above may be installed together with various control and protection systems such as a battery management system (BMS) and a cooling system to form a battery pack.

[0123] The battery module or battery pack can be applied to various devices. Specifically, these devices can be applied to vehicle devices such as electric bicycles, electric vehicles, hybrid vehicles, etc., but the present disclosure is not limited thereto and can be applied to various devices that can use secondary batteries.

[0124] Although the preferred embodiments of the present disclosure have been described in detail above, the scope of the present disclosure is not limited thereto, and various modifications and improvements made by those skilled in the art using the basic concept of the present disclosure defined in the appended claims also fall within the spirit and scope of the present disclosure.

[0125] Description of Reference Numbers

[0126] 200: Battery cell stack

[0127] 300: Lower plate

[0128] 400: Module Framework

[0129] 500: Thermally conductive resin layer

[0130] 600: Compression pad.

Claims

1. A battery module, comprising: a battery cell stack having a plurality of battery cells stacked thereon; a plate-shaped lower plate located below the battery cell stack; a module frame for covering an upper surface and two side surfaces of the battery cell stack; a thermally conductive resin layer between the lower plate and the battery cell stack; as well as a compression pad portion surrounding the thermally conductive resin layer, in: The module frame includes: a first side surface portion and a second side surface portion covering the two side surfaces of the battery cell stack; and a top portion covering the upper surface of the battery cell stack, in: The first side surface portion, the second side surface portion and the top portion are formed integrally, in: The thermally conductive resin layer includes a first thermally conductive resin layer and a second thermally conductive resin layer disposed apart from each other in a direction in which the electrode lead protrudes from the battery cell, wherein the first thermally conductive resin layer and the second thermally conductive resin layer are provided to correspond to two end portions of the battery cell each having a protrusion of the electrode lead, respectively, and wherein a portion between the first thermally conductive resin layer and the second thermally conductive resin layer is arranged to correspond to a middle portion of the battery cell, in: The battery cell includes the electrode leads protruding in directions opposite to each other and a protrusion formed on one edge of the battery cell, and The protruding portion is located closer to one end portion of the lower plate in a direction in which one of the electrode leads protrudes than the compression pad portion.

2. The battery module according to claim 1, wherein: A first edge portion and a second edge portion of the lower plate facing each other are joined to the first side surface portion and the second side surface portion, respectively.

3. The battery module according to claim 2, wherein: The first edge portion and the second edge portion are welded and joined to the first side surface portion and the second side surface portion, respectively.

4. The battery module according to claim 1, wherein: The lower plate includes a mounting portion, and The mounting portion is formed on first and second edge portions of the lower plate facing each other.

5. The battery module according to claim 4, wherein: A mounting hole is formed in the mounting portion, and The mounting portion extends parallel to one surface of the lower plate.

6. The battery module according to claim 1, wherein: The thermally conductive resin layer is formed by applying a thermally conductive resin to the lower plate.

7. The battery module according to claim 1, wherein: The lower plate includes a step portion formed at the one end portion of the lower plate, and The protruding portion is located above the stepped portion.

8. The battery module according to claim 1, wherein: The thickness of the thermally conductive resin layer is equal to or thinner than the thickness of the compression pad portion.

9. The battery module according to claim 1, The battery module further includes a first compression pad surrounding the first thermally conductive resin layer and a second compression pad surrounding the second thermally conductive resin layer. 10 . A battery pack comprising the battery module according to claim 1 .

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