Battery Module

Abstract

The present invention discloses a battery module having improved heat dissipation performance so that heat in the battery module can be appropriately controlled. The battery module according to the present invention includes a cell assembly having a plurality of battery cells stacked in at least one direction, and a module case that houses the cell assembly in an internal space and has at least a portion of an internal surface having projections and recesses formed in a direction not parallel to the stacking direction of the battery cells.

Description

[Technical field]

[0001] This application claims priority to Korean Patent Application No. 10-2021-0132745 filed on October 6, 2021, the entire contents of which are incorporated herein by reference in their entirety in the specification and drawings.

[0002] The present invention relates to a battery, and more particularly to a battery module having improved heat dissipation performance, and a battery pack and a vehicle including the same. [Background technology]

[0003] In recent years, as the demand for portable electronic products such as notebook computers, video cameras, and mobile phones has increased dramatically and the commercialization of robots, electric vehicles, and the like has progressed in earnest, active research has been conducted into high-performance secondary batteries that can be repeatedly charged and discharged.

[0004] Currently, commercially available secondary batteries include nickel-cadmium batteries, nickel-metal hydride batteries, nickel-zinc batteries, and lithium secondary batteries. Of these, lithium secondary batteries are in the spotlight for their advantages over nickel-based secondary batteries, such as the almost complete absence of memory effect, which allows for free charging and discharging, a very low self-discharge rate, and a high energy density.

[0005] This type of lithium secondary battery mainly uses a lithium-based oxide and a carbon material as a positive electrode active material and a negative electrode active material, respectively, and includes an electrode assembly in which a positive electrode plate and a negative electrode plate coated with such a positive electrode active material and a negative electrode active material are arranged with a separator sandwiched therebetween, and an exterior material, such as a battery case, that encloses the electrode assembly together with an electrolyte.

[0006] In general, lithium secondary batteries are classified according to the shape of their exterior material into can-type secondary batteries in which an electrode assembly is housed in a metal can and pouch-type secondary batteries in which an electrode assembly is housed in a pouch made of an aluminum laminate sheet.

[0007] Recently, secondary batteries are widely used for driving and storing energy not only in small devices such as portable electronic devices but also in medium- to large-sized devices such as electric vehicles and energy storage systems (ESS). A battery module can be configured by housing a plurality of such secondary batteries together inside a module case in an electrically connected state. A battery pack can be configured by connecting a plurality of such battery modules.

[0008] When a secondary battery used in a battery module or a battery pack is used in an environment with a higher temperature than the appropriate temperature, the performance may be degraded, and in the worst case, there is a risk of explosion or fire. Furthermore, when a battery module is constructed using multiple secondary batteries, the heat from the multiple secondary batteries may be merged in a small space, causing the temperature of the battery module to rise more quickly and violently. In addition, in the case of a battery module used in an automobile or an energy storage system (ESS), since it may be located outdoors, there is a risk of heat being applied from the outside, such as direct sunlight or high temperatures. Therefore, it can be said that it is very important to control the temperature in a battery module, and in particular to cool the battery pack when the temperature of the battery pack rises.

[0009] In addition, an abnormal situation may occur in some battery cells among various battery cells (secondary batteries) arranged in a battery module, causing heat generation. Such heat generation may cause the temperature of the battery to constantly rise, and if it exceeds a certain threshold temperature, it may lead to a thermal runaway state. Furthermore, there is a possibility that the thermal runaway state may be propagated to other battery cells or other battery modules. If such a heat generation or thermal runaway state cannot be controlled normally, it may threaten the safety of the battery module or battery pack, and even the device in which such a battery is installed, such as an automobile or energy storage system, or the user who uses such a device.

[0010] Furthermore, although the capacity and output of batteries have increased in recent years, the need to shorten charging times is also increasing. Therefore, rapid charging technology for batteries is widely used, but there is a problem that the heat generated by the battery increases when rapid charging is performed. Therefore, it has been proposed that the heat generated by the battery needs to be appropriately controlled even in rapid charging mode. Summary of the Invention [Problem to be solved by the invention]

[0011] Therefore, the present invention has been made in consideration of the above problems, and aims to provide a battery module having improved heat dissipation performance so that the heat of the battery module can be appropriately controlled, and a battery pack and automobile including the same.

[0012] However, the technical problems that the present invention aims to solve are not limited to the problems described above, and other problems not mentioned will be clearly understood by those skilled in the art from the detailed description of the invention described below. [Means for solving the problem]

[0013] To achieve the above-mentioned objective, a battery module according to one aspect of the present invention includes a cell assembly having a plurality of battery cells stacked in at least one direction, and a module case that houses the cell assembly in an internal space and has at least a portion of its internal surface formed with projections and recesses in a direction not parallel to the stacking direction of the battery cells.

[0014] Here, the plurality of battery cells may be stacked in a left-right direction, and the concaves and convexes of the module case may be formed in a front-rear direction.

[0015] In addition, the battery module according to the present invention may further include a thermal resin interposed between the cell assembly and the inner surface of the module case having the irregularities.

[0016] Furthermore, the module case may include a top plate, a base plate, and a side plate, and the projections and recesses may be formed on the base plate.

[0017] Furthermore, the unevenness may be further formed on at least one of the top plate and the side plate.

[0018] Furthermore, the module case may have projections and recesses formed on at least a portion of the outer surface.

[0019] Furthermore, the module case may be configured so that the surface area of ​​the projections and recesses varies from the inside to the outside.

[0020] Furthermore, the module case may be configured such that projections and recesses are formed on each of the top plate and the base plate, and the projections and recesses formed on the top plate and the projections and recesses formed on the base plate have different shapes.

[0021] In order to achieve the above object, a battery pack according to another aspect of the present invention includes a battery module according to the present invention.

[0022] Furthermore, in order to achieve the above object, according to yet another aspect of the present invention, a vehicle includes a battery module according to the present invention. Effect of the Invention

[0023] According to one aspect of the present invention, it is possible to provide a battery module with improved heat dissipation and cooling performance.

[0024] Therefore, even if heat is generated inside the battery module, the internal heat is quickly discharged to the outside, thereby preventing heat from accumulating inside the battery module.

[0025] Furthermore, when rapid charging is performed, more heat may be released from the battery cells, but according to the above aspects of the present invention, it is possible to increase the heat release performance through the module case and module frame, so that even when a rapid charging operation is performed on the battery module, the temperature of the battery module does not increase rapidly and heat can be appropriately managed.

[0026] Furthermore, according to one embodiment of the present invention, a thermal resin may be interposed between the module case and the cell assembly, and in this case, the amount of thermal resin used can be reduced.

[0027] Furthermore, according to the above-described embodiment of the present invention, the contact area between the cell assembly and the thermal resin can be increased, and therefore, the amount of thermal resin used can be reduced while improving heat dissipation performance, thereby reducing costs and providing an economical battery module.

[0028] In addition to these, the present invention can have various other effects, which will be described in the sections for each embodiment, and descriptions of effects that can be easily inferred by a person skilled in the art will be omitted.

[0029] The drawings attached to this specification are intended to illustrate preferred embodiments of the present invention and serve to facilitate a further understanding of the technical ideas of the present invention as well as the content of the invention, and therefore the present invention should not be interpreted as being limited to only the matters depicted in the drawings. [Brief description of the drawings]

[0030] [Figure 1] 1 is a perspective view illustrating a schematic configuration of a battery module in an assembled state according to an embodiment of the present invention; [Diagram 2] FIG. 2 is an exploded perspective view of the battery module of FIG. 1. [Diagram 3] 1 is a cross-sectional view illustrating a schematic configuration of a portion of a battery module according to an embodiment of the present invention. [Figure 4] 4 is a cross-sectional view illustrating a schematic configuration of a portion of a battery module according to another embodiment of the present invention. [Diagram 5] 11 is a cross-sectional view illustrating a schematic configuration of a battery module according to still another embodiment of the present invention. [Figure 6] 11 is a cross-sectional view illustrating a schematic configuration of a portion of a battery module according to still another embodiment of the present invention. [Figure 7] 11 is a cross-sectional view illustrating a schematic configuration of a portion of a battery module according to still another embodiment of the present invention. [Figure 8] 4 is a cross-sectional view illustrating a schematic configuration of a portion of a battery module according to another embodiment of the present invention. [Figure 9] 13 is an exploded perspective view illustrating a schematic configuration of a portion of a battery module according to still another embodiment of the present invention. FIG. [Figure 10] 13 is an exploded perspective view illustrating a schematic configuration of a portion of a battery module according to still another embodiment of the present invention. FIG. [Figure 11] 11 is a cross-sectional view illustrating a schematic configuration of a portion of a battery module according to still another embodiment of the present invention. [Figure 12] 11 is a cross-sectional view illustrating a schematic configuration of a portion of a battery module according to still another embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0031] Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the attached drawings. Prior to this, the terms and words used in the present specification and claims are not to be construed as being limited to their ordinary or dictionary meanings, but are to be construed as having meanings and concepts corresponding to the technical ideas of the present invention, in accordance with the principle that the inventors themselves can appropriately define the concepts of terms in order to best describe the invention.

[0032] Therefore, it should be understood that the embodiment described in this specification and the configurations shown in the drawings are merely the most preferred embodiment of the present invention and do not represent the entire technical idea of ​​the present invention, and therefore there may be various equivalents and modifications that can be substituted therefor at the time of this application.

[0033] Fig. 1 is a perspective view of an assembled state, which shows a schematic configuration of a battery module according to an embodiment of the present invention, and Fig. 2 is an exploded perspective view of the battery module of Fig. 1. Fig. 3 is a cross-sectional view showing a schematic configuration of a portion of a battery module according to an embodiment of the present invention. In particular, Fig. 3 can be said to be a view showing a partial configuration of a cross section taken along the line A1-A1' of Fig. 1.

[0034] 1 to 3, a battery module according to the present invention includes a cell assembly 100 and a module case 200.

[0035] The cell assembly 100 may include one or more battery cells 110, particularly a plurality of battery cells 110. Here, each battery cell 110 may refer to a secondary battery. The secondary battery may include an electrode assembly, an electrolyte, and a battery case. In particular, the battery cell 110 disposed in the cell assembly 100 may be a pouch-type secondary battery. However, other types of secondary batteries, such as cylindrical batteries and prismatic batteries, may also be adopted in the cell assembly 100 of the present invention.

[0036] A plurality of battery cells 110 may be stacked in at least one direction to form a cell assembly 100. For example, a plurality of secondary batteries may be stacked in a form in which they are arranged in a horizontal direction (Y-axis direction in the figure) while being vertically erected (Z-axis direction in the figure). In this case, each battery cell 110 may be configured in a form in which the surface of the wide receiving portion is arranged on the left and right sides, respectively. Also, each battery cell 110 may have an electrode lead 111, which may be located at both ends of each battery cell 110 or at one end. A secondary battery in which the electrode lead 111 protrudes in both directions may be called a bidirectional cell, and a secondary battery in which the electrode lead 111 protrudes in one direction may be called a unidirectional cell. In the configurations of FIGS. 1 to 3, a bidirectional cell form in which the electrode lead 111 is located on the front and rear sides of the battery cell 110, respectively, is shown. However, the present invention is not limited in any way by the specific type or form of such a secondary battery, and various types of secondary batteries known at the time of filing the present application can be adopted in the cell assembly 100 of the present invention.

[0037] The module case 200 may be configured to have an internal space formed therein and to accommodate the cell assembly 100 in the internal space. For example, the module case 200 may be configured to include a plurality of plates (frames) and define an internal space when the plurality of plates are coupled to each other. The cell assembly 100 may be accommodated in the internal space defined by the plates of the module case 200. Therefore, the module case 200 may cover the outside of the cell assembly 100 in various directions, such as up, down, front, rear, left, and right.

[0038] The module case 200 may have projections and recesses formed on at least a part of the inner surface. For example, the module case 200 may have projections and recesses formed on the whole or a part of the bottom surface facing the lower part of the cell assembly 100, as shown by G in FIG. 2. Here, the projections and recesses G may include a convex portion formed in a convex shape toward the inside of the battery module and a concave portion formed in a concave shape toward the outside of the battery module. That is, the projections and recesses G may be formed in a shape in which the projections and recesses are arranged to intersect. Furthermore, in the module case 200, the projections and recesses G may be formed in a wave shape as shown in FIG. 3. That is, the projections and recesses G may be formed in a curved shape in which the projections and recesses are arranged to intersect, but are continuous with each other.

[0039] In particular, the direction of the unevenness may be formed in a direction that is not parallel to the stacking direction of the battery cells 110. For example, referring to the configurations of Fig. 2 and Fig. 3, the stacking direction of the battery cells 110 is formed in the Y-axis direction, whereas the unevenness of the module case 200 may not be formed in the Y-axis direction, but may be formed in another direction, i.e., in a direction inclined at a predetermined angle from the Y-axis direction.

[0040] According to this embodiment of the present invention, the unevenness formed on the inner surface of the module case 200 can improve the heat dissipation efficiency of the cell assembly 100 through the module case 200. That is, according to the above embodiment, the surface area of ​​the inside of the module case 200 is increased in the portion where the unevenness is formed, so that the heat transfer ability between the cell assembly 100 and the module case 200 can be increased.

[0041] Furthermore, in the case of a battery module according to the present invention, the concaves and convexes of the module case 200 are formed in a direction different from the stacking direction of the battery cells 110, so that each battery cell 110 can come into contact with a plurality of concaves and convexes. For example, referring to FIG. 3, a lower portion of one battery cell 110 may be disposed to face a plurality of convex portions and a plurality of concave portions formed on the module case 200.

[0042] According to such a structural aspect of the present invention, it is possible to further improve the heat dissipation performance of each battery cell 110. That is, since each battery cell 110 included in the cell assembly 100 contacts a plurality of protrusions and a plurality of recesses of the module case 200, the heat dissipation efficiency of each battery cell 110 through the module case 200 can be further improved.

[0043] In particular, referring to FIG. 2, in a battery module according to the present invention, a plurality of battery cells 110 may be stacked in the left-right direction (Y-axis direction). In this case, the unevenness of the module case 200 may be formed in the front-rear direction (X-axis direction). More specifically, referring to FIG. 3, the unevenness of the module case 200 may be configured in a form in which convex portions and concave portions are repeatedly arranged in the X-axis direction, which is the front-rear direction. In such an embodiment, it can be said that the direction in which the unevenness of the module case 200 is formed is perpendicular to the stacking direction of the plurality of battery cells 110.

[0044] According to such an embodiment of the present invention, each battery cell 110 can face a large number of projections and recesses. Therefore, the heat dissipation performance through the module case 200, particularly the heat dissipation performance through the portion of the module case 200 where the projections and recesses are formed, can be further improved.

[0045] 4 is a cross-sectional view showing a schematic configuration of a portion of a battery module according to another embodiment of the present invention. In describing this embodiment and other embodiments of the present invention, detailed descriptions of parts that are the same or similar to the descriptions of other embodiments will be omitted, and the description will focus on differences.

[0046] 4, the battery module according to the present invention may further include a thermal resin 300. The thermal resin 300 may be interposed between the module case 200 and the cell assembly 100. In particular, as described above, the module case 200 may have irregularities, and the thermal resin 300 may be located on the inner surface side of the portion of the module case 200 where such irregularities are formed. Therefore, the thermal resin 300 may be interposed at least between the portion of the module case 200 where the irregularities are formed and the cell assembly 100.

[0047] The thermal resin 300 is a component capable of transferring heat between the battery cells 110 and the module case 200, and may be made of a variety of heat conductive materials known at the time of filing of the present invention. That is, the battery module according to the present invention is not limited by the specific type of the thermal resin 300. In particular, the thermal resin 300 may be injected or applied between the battery cells 110 and the module case 200 in a fluid state, and may be configured to be fixed in place by curing. The thermal resin 300 may also include an adhesive material. For example, the thermal resin 300 may be realized by a thermally conductive adhesive.

[0048] When the thermal resin 300 is interposed between the module case 200 and the cell assembly 100, the heat dissipation efficiency of the cell assembly 100 through the module case 200 can be improved. Furthermore, in the battery module according to the present invention, the thermal resin 300 can be located in a portion where the unevenness is formed, and in this case, the amount of the thermal resin 300 used can be reduced. In particular, since a smaller amount of the thermal resin 300 is interposed in a portion where the protrusion is formed in the unevenness, the amount of the thermal resin 300 used can be reduced. Therefore, according to this aspect of the present invention, the material cost can be reduced, and the manufacturing cost of the battery module can be reduced.

[0049] 2, the module case 200 may include a top plate 210, a base plate 220, and a side plate 230. The module case 200 may define an internal space with these components, i.e., the top plate 210, the base plate 220, and the side plate 230, and may accommodate the cell assembly 100 in the internal space. Here, the top plate 210 may be located at an upper portion of the module case 200, and the base plate 220 may be disposed below the top plate 210 and spaced a predetermined distance from the top plate 210. Also, the side plate 230 may be disposed between the top plate 210 and the base plate 220, with the upper end and the lower end connected to each other.

[0050] The top plate 210, the base plate 220, and / or the side plate 230 may be configured in a thin sheet shape, i.e., a plate shape, but may be configured in a polyhedral shape, for example, a rectangular parallelepiped shape, having a thickness of a certain level or more. Furthermore, the side plate 230 may include a left plate 231, a right plate 232, a front plate 233, and a rear plate 234. The top plate 210, the base plate 220, and / or the side plate 230 may be entirely or partially made of a metal material. Also, at least a part of them may be made of a plastic material. For example, the left plate 231, the right plate 232, the top plate 210, and the base plate 220 may be made of a steel material. And the front plate 233 and the rear plate 234 may be made of a plastic material.

[0051] At least some of the top plate 210, the base plate 220, and the side plate 230 may be configured to be integrated with each other. For example, as shown in FIG. 2, the left plate 231 and the right plate 232 among the four side plates 230 may be configured to be integrated with the base plate 220. In this case, the left plate 231, the right plate 232, and the base plate 220 that are integrated with each other may be referred to as a U-frame or the like due to their shape. In this case, the front plate 233 and the rear plate 234 are end plates and may be respectively coupled to the openings at the front and rear ends of the U-frame. And the top plate 210 may be coupled to the opening at the upper end of the U-frame.

[0052] However, in addition to these, the module case 200 may be configured in various other forms. For example, the base plate 220 and the four side plates 230 may be integrated with each other to form a box-shaped lower case. In this case, the top plate 210 may be coupled to an opening at the top end of the box-shaped lower case. As another example, the base plate 220, the left plate 231, the right plate 232, and the top plate 210 may be integrated with each other to form a tubular case. In this case, the tubular case may be referred to as a monoframe. Alternatively, the top plate 210, the base plate 220, the left plate 231, the right plate 232, the front plate 233, and the rear plate 234 may be manufactured in separate forms, and then the corners of the top plate 210, the base plate 220, the left plate 231, the right plate 232, the front plate 233, and the rear plate 234 may be coupled together during the assembly process.

[0053] Meanwhile, various types of connection methods may be adopted for the configuration in which the components are not manufactured in an integrated form in the module case 200 but are connected during the assembly process of the battery module. For example, the top plate 210, the front plate 233, and the rear plate 234 may be connected to the U-frame by laser welding or ultrasonic welding. Alternatively, each component of the module case 200 may be connected to each other by a bolt fastening method, etc.

[0054] In the configuration of the module case 200 as described above, the unevenness may be formed on the base plate 220. That is, as shown in Figures 2 and 3, the unevenness may be formed on the upper surface of the base plate 220 on which the cell assembly 100 is placed.

[0055] In the module case 200, the part that can be positioned closest to the cell assembly 100 is the base plate 220. Therefore, when the inner surface of the base plate 220 is formed with irregularities, the heat dissipation effect of the cell assembly 100 via the irregularities is further improved.

[0056] Furthermore, such an embodiment of the present invention is further suitable for use when applied to an apparatus in which a heat dissipation path is disposed under a battery module. For example, when a cooling component, such as a refrigerant pipe, is provided under the battery module, a better heat dissipation effect can be obtained if unevenness is formed on the inner surface of the base plate 220.

[0057] Furthermore, in the configuration of module case 200 as described above, the unevenness may be formed on a plurality of different side surfaces of module case 200. In particular, the unevenness may be further formed on at least one of top plate 210 and side plate 230 in addition to base plate 220. This will be described further with reference to FIG. 5.

[0058] Fig. 5 is a cross-sectional view showing a schematic configuration of a battery module according to another embodiment of the present invention. Furthermore, Fig. 5 is another form of the configuration of the cross section taken along the line A1-A1' in Fig. 1, and can be said to be a view showing a part of the configuration. In particular, Fig. 5 does not show the front plate 233 and the rear plate 234.

[0059] 5, the unevenness may be formed on both the upper surface of the base plate 220 and the lower surface of the top plate 210. In this case, one battery cell 110 may come into contact with multiple unevenness on both the upper and lower surfaces.

[0060] According to this embodiment of the present invention, the heat dissipation performance of the cell assembly 100 can be improved from multiple sides, particularly from both the top and bottom. In particular, in a configuration in which multiple pouch-type cells are arranged in a horizontal direction, as in the above embodiment, a dual cooling method in which cooling is performed on both the top and bottom of the battery module can be used. Furthermore, in the current situation where requirements for fast charging are becoming increasingly strict, the possibility of adopting the dual cooling method may be further increased. In this case, when both the base plate 220 and the top plate 210 are formed with unevenness as in the above embodiment, the cooling performance of such a dual cooling method can be further improved.

[0061] 6 is a cross-sectional view showing a schematic configuration of a portion of a battery module according to another embodiment of the present invention, for example, FIG. 6 shows another modified embodiment of the configuration of FIG.

[0062] 6, the module case 200 may have unevenness formed on at least a portion of the outer surface. More specifically, in the configuration of FIG. 6, the base plate 220 may have unevenness formed on both the upper surface and the lower surface. In this case, it can be said that the module case 200, i.e., the base plate 220, has unevenness formed not only on the inner surface but also on the outer surface. In this case, the areas of both the inner surface and the outer surface of the base plate 220 may be increased.

[0063] According to this embodiment, when heat is generated on the cell assembly 100 side, more heat can be absorbed through the unevenness formed on the inner surface of the module case 200. Furthermore, more heat can be released to the outside through the unevenness formed on the outer surface of the module case 200. Furthermore, as shown by C in FIG. 6, a cooling component can be disposed on the outside of the battery module. Such a cooling component can be a battery pack or a cooling pipe provided in a device to which a battery pack is attached, such as an automobile. In this case, the heat of the cell assembly 100 can be more quickly and smoothly released to the cooling component C through the unevenness formed on both sides of the base plate 220, i.e., the module case 200.

[0064] In the above embodiment, a thermal interface material may be interposed between the outer surface of the base plate 220 and the cooling component C, as shown by T in Fig. 6. In particular, such a thermal interface material may be filled into the irregularities formed on the outer surface of the base plate 220. In this case, the contact area between the thermal interface material and the base plate 220 increases, thereby improving the cooling efficiency of the base plate 220.

[0065] Meanwhile, in module case 200, the unevenness may not be formed uniformly overall, but may be configured to have partially different shapes, which will be described in more detail with reference to FIG.

[0066] 7 is a cross-sectional view illustrating a schematic configuration of a portion of a battery module according to another embodiment of the present invention, for example, FIG. 7 is another modified example of the configuration of FIG.

[0067] Referring to FIG. 7, the module case 200 may be configured to have a difference in surface area of ​​the projections and recesses as it moves from the inside to the outside. For example, as shown in FIG. 7, in a state where the cell assembly 100 and the base plate 220 are arranged, the central portion indicated by D2 is the inner portion, and the peripheral portions indicated by D1 and D3 are the outer portion. In this case, at least two of the portions indicated by D1, D2, and D3 may be configured to have different shapes of projections and recesses, in particular, different surface areas. Here, making the surface areas of the projections and recesses different can be realized by increasing the depth of the projections and recesses or shortening the distance between the projections of the projections and recesses. For example, when the projections and recesses are formed in a wavy shape, the surface area of ​​the projections and recesses can be increased by increasing the amplitude of the wavy shape or shortening the wavelength of the wavy shape.

[0068] More specifically, with respect to the configuration formed on the base plate 220 of FIG. 7, it can be seen that there is a change in the surface area of ​​the projections and recesses as one moves from the inside to the outside, i.e., from D2 to D1 or D3.

[0069] According to this embodiment of the present invention, more suitable heat dissipation performance can be ensured according to the difference in the shape of the projections and recesses in each part formed on the base plate 220, i.e., the module case 200. Furthermore, the cell assembly 100 may have different heat dissipation amounts depending on its position. Therefore, when the shape of the projections and recesses is partially changed on the module case 200 as in the above embodiment, it is possible to adaptively respond to the difference in the amount of heat dissipation. Therefore, in this case, heat can be dissipated more efficiently and uniformly.

[0070] In particular, the battery cell 110 may emit heat during charging and discharging, and the amount of heat emitted may vary from part to part. As a representative example, the battery cell 110 may generate and emit more heat in a part where the electrode lead 111 is located. In this case, the module case 200 may be configured such that the unevenness of the outer part close to the electrode lead 111 has a larger surface area than other parts. For example, as shown in FIG. 7, in the case of a base plate 220 disposed under the battery cell 110 in which the electrode lead 111 is provided at the front and rear, the outer part close to the electrode lead 111, i.e., the peripheral part, indicated by D1 and D3, may have deeper and more numerous unevenness than the central part indicated by D2. In particular, the central part indicated by D2 may be configured to have almost no unevenness and only protrusions.

[0071] According to such an embodiment of the present invention, the module case 200 can be formed so that the surface on which the electrode lead 111 is located has a higher heat absorption amount or heat absorption rate than other parts. Therefore, even if a relatively large amount of heat is emitted from the part of the battery cell 110 where the electrode lead 111 is located, the module case 200 can absorb a similarly large amount of heat, so that the temperature of the battery cell 110 can be made uniform overall.

[0072] In addition, according to the above embodiment, the amount of thermal resin 300 in the central portion as indicated by D2 can be reduced. That is, in the case of the portion indicated by D2, the recess is hardly formed, and the protrusion is mainly formed widely, so that the gap between the battery cell 110 and the base plate 220 can be eliminated or reduced. Therefore, in this portion, the amount of thermal resin 300 interposed between the base plate 220 and the battery cell 110 can be reduced.

[0073] 8 is a cross-sectional view illustrating a schematic configuration of a portion of a battery module according to another embodiment of the present invention. In particular, FIG. 8 can be considered as a modified example of the configuration of FIG.

[0074] 8, the module case 200 may have projections and recesses formed on each of the top plate 210 and the base plate 220. In this case, the projections and recesses formed on the top plate 210 and the base plate 220 may be configured to have different shapes. More specifically, the base plate 220 has projections and recesses formed uniformly in the horizontal direction (front-rear direction) that is the X-axis direction. In contrast, the top plate 210 has projections and recesses formed non-uniformly in the horizontal direction. In particular, the projections and recesses formed on the top plate 210 may be formed such that the surface area of ​​the projections and recesses on the outer side is larger than the surface area of ​​the projections and recesses on the inner side, similarly to the base plate 220 of FIG. 7. That is, in FIG. 8, the top plate 210 may be formed such that the depth of the projections and recesses is deeper in the peripheral portion than in the central portion. Also, the peripheral portion of the top plate 210 may have more projections and recesses formed on it based on the same horizontal distance than the central portion. In particular, in the case of the above embodiment, the concave and convex shapes of the top plate 210 and the base plate 220 are not symmetrical in the vertical direction, but are formed asymmetrically.

[0075] According to this embodiment of the present invention, when dual cooling is performed by the module case 200, a configuration for uniformly cooling the battery cells 110 as a whole can be more efficiently realized. For example, the base plate 220 has unevenness formed uniformly as a whole, and can absorb and release heat from the cell assembly 100. Although the temperature of the battery cells 110 may be partially uneven due to the cooling configuration of the base plate 220, the top plate 210 may have a configuration for eliminating such temperature unevenness. In particular, when the temperature of the electrode lead 111 side is relatively higher than other parts as a result of cooling by the base plate 220, the area of ​​the unevenness on the outer periphery of the top plate 210 may be relatively large as shown in FIG. 8. In this case, the top plate 210 can absorb more heat from the part on the electrode lead 111 side than the other parts. Therefore, the temperature of the battery cells 110 can be uniform as a whole as a result of combined cooling by the base plate 220 and the top plate 210.

[0076] 9 is an exploded perspective view illustrating a schematic configuration of a portion of a battery module according to still another embodiment of the present invention, in which the side plate 230 is not shown for ease of explanation.

[0077] 9, both the base plate 220 and the top plate 210 are formed with unevenness, but the directions of the unevenness may be different from each other. That is, the top plate 210 may have unevenness in the direction of the arrow F1, and the base plate 220 may have unevenness in the direction of the arrow F2. More specifically, the unevenness of the top plate 210 may be formed in a form in which the convex portions and the concave portions intersect repeatedly as it progresses in the direction of the arrow F1. And, the unevenness of the base plate 220 may be formed in a form in which the convex portions and the concave portions intersect repeatedly as it progresses in the direction of the arrow F2. In particular, the directions of the unevenness of the top plate 210 and the base plate 220 may be formed in a form in which the convex portions and the concave portions intersect repeatedly as it progresses in the direction of the arrow F2.

[0078] According to such an embodiment of the present invention, the cooling form of the upper side and the cooling form of the lower side of the same cell assembly 100 can be different from each other. In this case, it is advantageous to ensure a uniform cooling performance for the cell assembly 100 as a whole. Furthermore, when the thermal resin 300 is filled in the unevenness of the base plate 220 and the top plate 210, the amount of resin contacting the upper side and the amount of resin contacting the lower side of one battery cell 110 may differ. Therefore, it is possible to reduce the problem of a decrease in the cooling performance of a specific part of one battery cell 110. For example, according to the above embodiment, even if the amount of contact resin is small at the lower side of a certain part of one battery cell 110 due to contact with the convex part, the amount of contact resin may be large at the upper side of the part due to contact with the concave part. Therefore, it is possible to reduce the possibility that the amount of contact resin is small at both the upper side and the lower side at a certain part of one battery cell 110. Therefore, in this case, it is possible to ensure a uniform cooling performance for each battery cell 110 as a whole.

[0079] Also, according to the above embodiment, the heat dissipation form of the upper side and the heat dissipation form of the lower side of the cell assembly 100 may be different. For example, in the embodiment of FIG. 9, the top plate 210 may have a recess with a large contact surface area formed in an elongated shape in the direction of F2, and the base plate 220 may have a recess formed in an elongated shape in the direction of F1. In this case, the top plate 210 may be formed so that the heat dissipation direction is more likely to be in the same direction as F2, and the base plate 220 may be formed so that the heat dissipation direction is more likely to be in the direction of F1. Therefore, since the heat dissipation form may be different between the upper and lower parts of the cell assembly 100, it is possible to reduce the concentration of a large amount of heat in a specific direction in the battery module. Therefore, the overall cooling efficiency of the battery module may be improved.

[0080] 10 and 11 are an exploded perspective view and a cross-sectional view, respectively, illustrating a configuration of a part of a battery module according to still another embodiment of the present invention. In particular, Fig. 11 shows the cross-sectional configuration of Fig. 10 when assembled, taken along the line A2-A2'.

[0081] 10 and 11, in the battery module according to the present invention, the module case 200 may have micro-protrusions as indicated by J. Such micro-protrusions J may be formed in a shape that protrudes inwardly from the inner surface of the module case 200 in a convex shape. In particular, the micro-protrusions J may be provided in a portion of the module case 200 where the irregularities G are formed. For example, when the irregularities G are formed on the base plate 220 of the module case 200, a large number of micro-protrusions J may be provided on the inner surface of the base plate 220, i.e., the upper surface.

[0082] A large number of small protrusions J may be arranged horizontally, i.e., in the left-right direction (Y-axis direction) and the front-rear direction (X-axis direction), on the inner surface of the module case 200. In this case, the small protrusions J may have a size that is significantly smaller than the length of the module case 200. For example, the small protrusions J may be formed in a circular shape having a diameter and height of approximately 1 mm to 50 mm or less.

[0083] According to this embodiment of the present invention, the contact area between the module case 200 and the cell assembly 100 is further increased by the micro-protrusions J together with the irregularities G. Therefore, the efficiency and speed of heat transfer from the cell assembly 100 to the module case 200 is increased, and the cooling performance of the battery module can be improved. In addition, when the micro-protrusions J are applied in an embodiment in which the thermal resin 300 is interposed between the cell assembly 100 and the module case 200, the thermal resin 300 is prevented from moving significantly downward along the slope caused by the irregularities G on the surface of the module case 200. Therefore, the thermal resin 300 can be uniformly positioned in the portion where the irregularities G are formed.

[0084] 10 and 11, the module case 200 may have projections G formed in a configuration in which projections G1 and recesses G2 are alternately positioned. In this case, the small protrusions J may be disposed in the recesses G2 of the projections G of the module case 200. Furthermore, the end of the small protrusion J located in the recess G2 may be configured to be located at a position lower than the projection G1. In other words, the small protrusions J in the recess G2 may not be higher than the height of the projection G1.

[0085] According to this embodiment, it is possible for the micro-protrusions J located in the recesses G2 not to come into direct contact with the battery cells 110. Therefore, when the battery cells 110 are mounted on the inner surface of the module case 200, for example, on the upper surface of the base plate 220, problems such as the micro-protrusions J interfering with the mounting process or damaging the battery cells 110 can be prevented.

[0086] In addition, in the above embodiment, the micro protrusions J arranged on one surface of the module case 200 may be configured to have partially different density. Here, the density may be expressed by the number or height of the micro protrusions J compared to the same surface area of ​​the module case 200. In particular, the multiple micro protrusions J may be configured to have different density in the stacking direction of the battery cells 110.

[0087] For example, as shown in Fig. 10, when a plurality of battery cells 110 are stacked in the left-right direction on the upper part of the base plate 220, the number or shape of the multiple micro protrusions J may vary in the left-right direction. In particular, the multiple micro protrusions J may be configured in at least a part of the upper surface of the base plate 220 so as to have a gradually higher density as it progresses toward the center part based on the stacking direction (Y-axis direction) of the battery cells 110. In other words, the multiple micro protrusions J may be configured so as to have a gradually lower density as it progresses toward the outer periphery of the stacking direction of the battery cells 110.

[0088] According to this embodiment of the present invention, in the configuration of the cell assembly 100 in which a plurality of battery cells 110 are stacked, the cooling performance of the battery cell 110 located in the center portion can be improved. Therefore, it is possible to prevent a problem in which the temperature of the battery cell 110 stacked in the center becomes relatively higher than the temperature of the battery cell 110 stacked in the outer shell, and contribute to uniforming the temperature throughout the cell assembly 100.

[0089] 10 and 11, the description has been focused on the embodiment in which the microprotrusions J are provided on the base plate 220, but the microprotrusions J may also be provided on the top plate 210. When the microprotrusions J are provided on the top plate 210, the description of the microprotrusions J provided on the base plate 220 described above can be applied in the same or similar manner. This will be described in more detail with reference to the embodiment of FIG.

[0090] FIG. 12 is a cross-sectional view illustrating a schematic configuration of a portion of a battery module according to still another embodiment of the present invention.

[0091] 12, microprotrusions J may be formed on the top plate 210 as well as the base plate 220. In particular, the microprotrusions J formed on the top plate 210 may be configured to have a different shape, size, layout, etc. from the microprotrusions J formed on the base plate 220. For example, in the case of the base plate 220, the microprotrusions J may be formed in the recesses G2, and in the case of the top plate 210, the microprotrusions J may be formed in the protrusions G1. Here, the protrusions G1 of the top plate 210 may be a portion formed in a convex shape toward the cell assembly 100, i.e., toward the lower portion, in the concave-convex configuration of the lower surface of the top plate 210.

[0092] According to this embodiment of the present invention, the cell assembly 100 can be more stably accommodated in the module case 200. Furthermore, in the case of the base plate 220, the cell assembly 100 may directly contact the upper surface, but the small protrusion J is formed in the recess G2, so that the flat part of the protrusion G1 can stably contact the lower part of the cell assembly 100. The space between the lower surface of the top plate 210 and the cell assembly 100 may have a shape that is somewhat separated due to tolerances, etc. At this time, the small protrusion J is formed in the protrusion G1 close to the cell assembly 100 side, so that the small protrusion J can be located close to the upper part of the cell assembly 100 or can be in direct contact. Therefore, the accommodation state of the battery cell 110, particularly the accommodation state in which the battery cell 110 is upright in the vertical direction and stacked in the horizontal direction, can be more stably maintained. In this case, the heat transfer efficiency between the cell assembly 100 and the module case 200, particularly the top plate 210, can be increased.

[0093] The battery pack according to the present invention may include one or more of the battery modules according to the present invention described above. In addition to the battery module, the battery pack according to the present invention may further include various other components, such as a battery management system (BMS), bus bars, a pack case, a relay, a current sensor, and other battery pack components that are already known at the time of filing of the present invention.

[0094] The battery module according to the present invention is applicable to automobiles such as electric automobiles and hybrid automobiles. That is, the automobile according to the present invention may include the battery module according to the present invention or the battery pack according to the present invention. Furthermore, the automobile according to the present invention may further include various other components included in the automobile, in addition to such a battery module or battery pack. For example, the automobile according to the present invention may further include a vehicle body, a motor, a control device such as an electronic control unit (ECU), and the like, in addition to the battery module according to the present invention.

[0095] In particular, there is an increasing need for rapid charging technology for automobiles driven by motors in recent years. Under such circumstances, in the case of an automobile employing the battery module according to the present invention, excellent heat dissipation and cooling performance can be ensured even during rapid charging.

[0096] Furthermore, the battery module according to the present invention is applicable to an energy storage system (ESS), that is, the energy storage system according to the present invention may include the battery module according to the present invention or the battery pack according to the present invention.

[0097] Meanwhile, although directional terms such as up, down, left, right, front, and back can be used in this specification, it will be obvious to those skilled in the art of the present invention that these terms are used merely for convenience of explanation and may vary depending on the position of the object in question or the position of the observer.

[0098] Although the present invention has been described above using limited embodiments and drawings, the technical concept of the present invention is in no way limited thereto, and it goes without saying that a person having ordinary knowledge in the technical field to which the present invention pertains can make various modifications and variations within the scope of the technical concept of the present invention and the equivalent scope of the claims. [Explanation of symbols]

[0099] 100 Cell Assembly 110 Battery Cell 111 Electrode lead 200 module case 210 top plate, 220 base plate, 230 Side Plate 231 Left side plate, 232 Right side plate, 233 forward plate, 234 Rear plate 300 Thermal Resin G unevenness

Claims

1. A cell assembly including a plurality of battery cells stacked in at least one direction; a module case that houses the cell assembly in an internal space and has an internal surface on at least a portion of which an unevenness is formed in a direction that is not parallel to a stacking direction of the battery cells; The projections and recesses contact the battery cells. Battery module.

2. 2. The battery module according to claim 1, wherein the plurality of battery cells are stacked in a stacking direction parallel to a longitudinal direction of the battery cells, and the projections and recesses of the module case are formed in a direction perpendicular to the stacking direction.

3. The battery module according to claim 1 , further comprising a thermal resin interposed between the cell assemblies and an inner surface of the module case having projections and recesses.

4. A cell assembly comprising a plurality of battery cells stacked in at least one direction; a module case that houses the cell assembly in an internal space and has an internal surface on at least a portion of which an unevenness is formed in a direction that is not parallel to a stacking direction of the battery cells; the module case includes a top plate, a base plate, and a side plate, and the projections and recesses are formed on the base plate. Battery module.

5. The battery module according to claim 4 , wherein the unevenness is further formed on at least one of the top plate and the side plate.

6. The battery module according to claim 1 , wherein the module case has an outer surface having projections and recesses formed on at least a portion of the outer surface.

7. The battery module according to claim 1 , wherein the module case is configured to have a difference in surface area between the projections and recesses as proceeding from the inside to the outside.

8. A cell assembly comprising a plurality of battery cells stacked in at least one direction; a module case that houses the cell assembly in an internal space and has an internal surface on at least a portion of which an unevenness is formed in a direction that is not parallel to a stacking direction of the battery cells; the module case includes a top plate and a base plate, the top plate and the base plate each have a projection and recess, and the projection and recess formed on the top plate and the projection and recess formed on the base plate have shapes different from each other; Battery module.

9. A battery pack comprising the battery module according to any one of claims 1 to 8.

10. A motor vehicle comprising a battery module according to any one of claims 1 to 8.

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