Cooling member, method for manufacturing the same, and battery pack including the same

Abstract

According to one embodiment of the present invention, there is provided a cooling member for cooling a battery cell, the cooling member comprising an upper plate, a lower plate, and an in / out port for injecting coolant into an internal space between the upper plate and the lower plate, the cooling member comprising an indentation formed by the upper plate being introduced into the lower plate or the lower plate being introduced into the upper plate, a first indentation formed in a peripheral portion of the cooling member and a second indentation formed in a central portion of the cooling member, and a sealing pad positioned between the upper plate and the lower plate forming the first indentation.

Description

Technical Field

[0001] [Cross - reference to Related Applications] This application claims the benefit of priority based on Korean Patent Application No. 10 - 2021 - 0086816, filed on July 2, 2021, and all the contents disclosed in the literature of the Korean patent application are incorporated herein by reference in their entirety.

[0002] Relates to a cooling member, a method for manufacturing the same, and a battery pack including the same.

Background Art

[0003] In modern society, with the daily use of portable devices such as mobile phones, laptops, camcorders, and digital cameras, the development of technologies in fields related to such mobile devices has become active. In addition, rechargeable secondary batteries are used as power sources for electric vehicles (EVs), hybrid electric vehicles (HEVs), plug - in hybrid electric vehicles (P - HEVs), etc., as a solution to problems such as air pollution caused by existing gasoline vehicles that use fossil fuels. As a result, the need for the development of secondary batteries is increasing.

[0004] Currently commercialized secondary batteries include nickel - cadmium batteries, nickel - metal hydride batteries, nickel - zinc batteries, lithium secondary batteries, etc. Among these, lithium secondary batteries are the most widely noted because of their advantages such as free charge and discharge, low self - discharge rate, and high energy density.

[0005] On the other hand, in the case of secondary batteries used in small devices, mainly 2 to 3 battery cells are used. In the case of secondary batteries used in medium - to - large - sized devices such as automobiles, medium - to - large - sized battery modules in which a large number of battery cells are electrically connected are used. Since medium - to - large - sized battery modules are preferably manufactured with the smallest possible size and weight, prismatic batteries, pouch - type batteries, etc. that can be stacked with a high degree of integration and have a small weight compared to their capacity are mainly used as the battery cells of medium - to - large - sized battery modules.

[0006] On the one hand, the battery cells mounted on the battery module may generate a large amount of heat during the charge and discharge process. If the temperature becomes higher than the appropriate temperature due to reasons such as overcharging, the performance may decrease. If the temperature rise is excessive, there is a risk of explosion or ignition. When an ignition phenomenon occurs inside the battery module, high-temperature heat, gas, or flame may be released to the outside of the battery module. At this time, heat, gas, spark, or flame released from one battery module may be transmitted to other adjacent battery modules placed at a narrow interval within the battery pack, and thus a continuous thermal runaway phenomenon may occur within the battery pack.

[0007] In order to prevent such a thermal runaway phenomenon, conventional battery modules may be provided with cooling members or heat dissipation members, etc. Recently, the application of water-cooled cooling members or water-cooled heat dissipation members injected with cooling water has been attempted.

[0008] FIG. 1 is a drawing showing a water-cooled cooling member provided in a battery cell laminate.

[0009] Referring to FIG. 1, the water-cooled cooling member 50 can be located on the upper part of the battery cell laminate 10 as shown. In the case of an air-cooled cooling member without the provision of cooling water, there was a problem that the battery cell laminate 10 was not uniformly cooled due to the formation of a temperature gradient in the cooling member depending on the position of the fan. However, in the case of the water-cooled cooling member 50, since the temperature of the cooling member 50 can be maintained relatively constant by the cooling water injected along the arrow direction, there is an advantage that the temperature deviation of the cooling member 50 is minimized.

[0010] The water-cooled cooling member 50 is formed by joining an upper plate and a lower plate, and cooling water is accommodated in the space between the upper plate and the lower plate. Conventionally, in order to ensure watertightness, methods such as welding were mainly used to join the upper plate and the lower plate. However, when the physical properties of the upper plate and the lower plate are different from each other, or when at least one of the upper plate and the lower plate partially includes a material with different physical properties, the upper plate and the lower plate may not be well joined by welding, or the upper plate and the lower plate may be damaged during the joining process. Therefore, there was a problem that the materials usable for the water-cooled cooling member 50 were limited.

[0011] Therefore, in fact, a technology that can solve such problems of the prior art is needed.

Summary of the Invention

Problems to be Solved by the Invention

[0012] The problem to be solved by the present invention is to provide a cooling member to which a cooling method using cooling water can be applied, a manufacturing method thereof, and a battery pack including the same.

[0013] However, the problems to be solved by the embodiments of the present invention are not limited to the above-mentioned problems, and can be variously extended within the scope of the technical idea included in the present invention.

Means for Solving the Problems

[0014] A cooling member according to an embodiment of the present invention is a cooling member for cooling a battery cell, including an upper plate, a lower plate, and an in-out port for injecting cooling water into an internal space between the upper plate and the lower plate. The cooling member includes a recessed portion formed by introducing the upper plate into the lower plate or the lower plate into the upper plate. A first recessed portion is formed at a peripheral portion of the cooling member, and a second recessed portion is formed at a central portion of the cooling member. A sealing pad is located between the upper plate and the lower plate forming the first recessed portion.

[0015] The recessed portion has a depth, and the direction in which the depth extends can be perpendicular to the flow direction of the cooling water inside the cooling member.

[0016] The recessed portion includes an upper recessed portion where the upper plate is deformed and a lower recessed portion where the lower plate is deformed, and the lowest point on the upper surface of the upper recessed portion can be located below the upper surface of the lower plate where the recessed portion is not formed.

[0017] The lowest point on the upper surface of the upper recessed portion can be located below the lower surface of the lower plate where the recessed portion is not formed.

[0018] The recessed portion includes an upper recessed portion where the upper plate is deformed and a lower recessed portion where the lower plate is deformed, and the maximum value of the outer diameter of the upper recessed portion may be larger than the minimum value of the inner diameter of the lower recessed portion.

[0019] The second recessed portion can be formed in an elongated groove formed along the length direction of the cooling member.

[0020] The recessed portion can include a third recessed portion located between the first recessed portion and the second recessed portion in the width direction of the cooling member.

[0021] The lower plate can include a first portion formed of a first material and a second portion formed of a second material different from the first material.

[0022] A method for manufacturing a cooling member according to another embodiment of the present invention includes the steps of positioning a sealing pad at the periphery of an upper plate, laminating the upper plate with the sealing pad thereon and a lower plate, joining the peripheral portions of the upper plate and the lower plate with the sealing pad therebetween by forming a first recessed portion, and forming a cooling flow path in the central portions of the upper plate and the lower plate by forming a second recessed portion.

[0023] The manufacturing method of the cooling member may further include a step of forming a deformation prevention structure at the central portions of the upper plate and the lower plate by forming the third bent portion.

[0024] The step of joining the peripheral portions of the upper plate and the lower plate includes a step of preparing a laminate in which the upper plate, the sealing pad, and the lower plate are laminated in this order, a step of aligning the laminate with a die, a step of advancing a punch toward the laminate, a step of locally pressing the laminate by the punch so that the laminate deforms according to the recess shape of the die, and a step of retracting the punch so as to move away from the laminate.

[0025] After the step of retracting the punch so as to move away from the laminate, a step of aligning the laminate with the second die may be included.

[0026] A battery module according to another embodiment of the present invention may include the above-described cooling member.

[0027] A battery pack according to another embodiment of the present invention may include the above-described cooling member.

[0028] The battery pack may include a battery module having a module-less structure.

Advantages of the Invention

[0029] According to the embodiment, by applying a mechanical fastening method instead of the conventional welding method, a cooling member to which various materials are applied can be manufactured.

[0030] The effects of the present invention are not limited to the effects mentioned above, and other effects not mentioned will be clearly understood by those skilled in the art from the description of the claims.

Brief Description of the Drawings

[0031]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Embodiments for Carrying Out the Invention

[0032] Hereinafter, various embodiments of the present invention will be described in detail with reference to the attached drawings so that those having ordinary knowledge in the technical field to which the present invention belongs can easily implement it. The present invention can be realized in various different forms other than those described below, and the scope of the present invention is not limited by the embodiments described here.

[0033] To clearly explain the present invention, parts that are unnecessary for the explanation are omitted, and the same reference numerals are given to the same or similar components throughout the specification.

[0034] In addition, the sizes and thicknesses of the respective components shown in the drawings are arbitrarily enlarged or reduced for the sake of convenience of explanation, so it is obvious that the content of the present invention is not limited to what is shown in the drawings. In the following drawings, the thicknesses of the respective layers are enlarged to clearly represent a plurality of layers and regions. And in the following drawings, for the sake of convenience of explanation, the thicknesses of some layers and regions are exaggeratedly shown.

[0035] In addition, when explaining that a part such as a layer, a film, a region, or a plate is "above" another part, this should be interpreted to include not only the case where the corresponding part such as the layer, the film, the region, or the plate is "directly above" another part, but also the case where there are other parts in between. Conversely, when explaining that the corresponding part such as the layer, the film, the region, or the plate is "directly above" another part, it may mean that there are no other parts in between. Also, being "above" a reference part means being located above or below the reference part, and does not necessarily mean being located "above" in the direction opposite to gravity. On the other hand, similar to the explanation of being "above" another part, the explanation of being "below" another part can also be understood with reference to the above-mentioned content.

[0036] In addition, since the upper surface / lower surface of a specific member can be determined differently depending on the reference direction, throughout the specification, "upper surface" or "lower surface" is defined to mean the two surfaces facing each other on the z-axis of the member.

[0037] Also, throughout the specification, when a part "includes" a certain component, this means that, unless otherwise stated to the contrary, other components are not excluded and other components can be further included.

[0038] Also, throughout the specification, when referring to "on a plane", this means when looking at the target part from above, and when referring to "in a cross-section", this means when looking at the cross-section obtained by vertically cutting the target part from the side.

[0039] Hereinafter, a cooling member according to an embodiment of the present invention will be described.

[0040] Figure 2 is a perspective view showing a cooling member according to an embodiment of the present invention. Figure 3 is a drawing showing an upper plate included in the cooling member of Figure 2. Figure 4 is a drawing showing a lower plate included in the cooling member of Figure 2.

[0041] Referring to Figure 2, the cooling member 500 of the present embodiment can be provided to lower the internal temperature of a battery module or a battery pack including a battery cell. The cooling member 500 can be a water-cooled cooling member 500 into which a refrigerant or cooling water is injected. By providing the cooling member 500 in a water-cooled manner, the cooling efficiency of the cooling member 500 can be maintained uniformly, and the battery cells in the battery module or the battery pack can be cooled uniformly. At this time, as the cooling water used for the cooling member 500, one of known ones or a mixture thereof can be used, and any of known ones may be used as long as it can release the heat of the battery cell by moving along the flow path inside the cooling member 500.

[0042] The cooling member 500 can be disposed on one surface of the battery cell stack to release the heat of the battery cell. The cooling member 500 can be disposed parallel to the stacking direction of the battery cell stack so as to be close to a large number of battery cells of the battery cell stack. Specifically, the cooling member 500 can be located above the battery cell stack (in the +z-axis direction of Figure 11). However, this is not necessarily the case, and depending on the design, the cooling member 500 may be located below the battery cell stack (in the -z-axis upward direction) or on the side portion (in the + / -y-axis upward direction).

[0043] The size of the cooling member 500 can be adjusted according to the size of the battery cell stack to which the cooling member 500 is applied. As an example, the cooling member 500 can be provided to correspond to one battery cell stack. At this time, the length of the cooling member 500 can be adjusted according to the length of the battery cell stack, or can be made larger or smaller with a certain margin, and the width of the cooling member 500 can be adjusted according to the width of the battery cell stack, or can be made larger or smaller with a certain margin. As another example, the cooling member 500 can be provided to correspond to a plurality of battery cell stacks. At this time, the length and width of the cooling member 500 can be adjusted according to the length and width of the plurality of battery cell stacks, or can be made larger or smaller with a certain margin. Here, the cooling member 500 can be located inside the battery module, but it is also possible to be located inside the battery pack 1000 (see FIG. 11) outside the battery module.

[0044] The cooling member 500 can include an upper plate 510 and a lower plate 520 that form the outer shape of the cooling member 500, and an inlet / outlet port 530 for injecting cooling water into the cooling member 500.

[0045] The cooling member 500 can be formed by joining the peripheries of the upper plate 510 and the lower plate 520. A sealing portion 540 formed by joining the peripheries of the upper plate 510 and the lower plate 520 of the cooling member 500 can be located at the peripheral portion of the cooling member 500. Cooling water can be built in or circulated between the joined upper plate 510 and lower plate 520 in the cooling member 500.

[0046] Cooling water can be supplied through the inlet ports 530 positioned side by side and discharged to the outlet ports 530. The inlet ports 530 and the outlet ports 530 can be positioned side by side in parallel on one end side of the cooling member 500. This can be for the purpose of simplifying the design regarding the inflow and discharge of the cooling water supplied from outside the battery module or the battery pack. Also, this can be for the purpose of minimizing the temperature difference between the periphery of the inlet ports 530 and the periphery of the outlet ports 530. Specifically, the cooling water flowing into the inlet ports 530 can have the lowest temperature, and the cooling water discharged to the outlet ports 530 can have the highest temperature. Therefore, when the inlet / outlet ports 530 are arranged adjacent to each other, the temperature deviation of the entire cooling water flowing through the internal space of the cooling member can be minimized due to heat exchange between them. Therefore, by arranging the inlet / outlet ports 530 side by side, the cooling member 500 can have a uniform heat dissipation performance as a whole.

[0047] A flow path forming groove 550 may be formed in the cooling member 500. By providing the flow path forming groove 550 in the cooling member 500, the flow of the cooling water supplied to the cooling member 500 can be determined. A plurality of flow path forming grooves 550 may be formed, and the plurality of flow path forming grooves 550 can be positioned along a single straight line parallel to the length direction of the cooling member 500. The flow path forming groove 550 can be continuously formed along the length direction of the cooling member 500 at the center of the cooling member 500 except for a predetermined section, and thus the flow of the cooling water can be formed in a U shape. The flow of the cooling water injected through the inlet port 530 of the cooling member 500 can be restricted by the flow path forming groove 550. By flowing along the U shape, the cooling water injected through the inlet port 530 can be discharged to the outlet port 530 positioned beside the inlet port 530. Specifically, the U-shaped flow path through which the cooling water flows includes a first flow path extending from the inlet port 530 along a straight line parallel to the length direction of the cooling member 500, a second flow path extending along a curve rotating clockwise or counterclockwise at the end of the first flow path, and a third flow path extending along a straight line parallel to the length direction of the cooling member 500 toward the outlet port 530 at the end of the second flow path.

[0048] The cooling member 500 may be formed with deformation prevention grooves 560. By providing the cooling member 500 with the deformation prevention grooves 560, the shape deformation of the cooling member 500 due to the cooling water can be prevented. For example, when the cooling water is injected into the cooling member 500, the injected cooling water can be concentrated in the 1 / 2 space of the cooling member 500 by the flow path forming groove 550 that crosses the center. Before the cooling water moves to the remaining 1 / 2 space through the U-shaped flow path, a large pressure can act on this space, and for this reason, at least a part of the cooling member 500 may expand or the cooling member 500 may be damaged. When the deformation prevention grooves 560 are formed in the flow path of the cooling member 500, even if a large pressure acts on a specific section due to the temporary concentration of the cooling water, the deformation caused thereby can be minimized. The deformation prevention grooves 560 may be arranged at intervals, partially in the U-shaped flow path through which the cooling water flows in the cooling member 500. The deformation prevention grooves 560 can be located between the flow path forming groove 550 and the sealing portion 540 in the width direction of the cooling member 500. The specific position of the deformation prevention grooves 560 can be appropriately set so as to correspond to the flow rate and flow velocity of the cooling water while not excessively disturbing the cooling water flowing in through the inlet port 530. Here, the width direction of the cooling member 500 can be a direction parallel to the short side of the cooling member 500. Also, here, the length direction of the cooling member 500 can be a direction parallel to the long side of the cooling member 500.

[0049] Further, a protrusion extending from one side of the cooling member 500 and continuously positioned along the length direction of the cooling member 500 may be formed around the cooling member 500. As illustrated in FIG. 11 described later, the protrusion may contact or be disposed in proximity to the electrode lead of each battery cell laminate or the bus bar connected to the electrode lead. Since the electrode lead or bus bar that provides electrical connection in the battery module or battery pack is a configuration that easily generates heat, if the above-described protrusion promotes the heat dissipation of the electrode lead or bus bar, the temperature rise of the battery cell can be more efficiently prevented.

[0050] Referring to FIG. 3, the upper plate 510 is provided in a plate shape, but its central portion can be formed to be recessed or indented to have a step with the peripheral portion. Specifically, the upper plate 510 can have a concave shape based on the cross-section in the width direction. This can be formed by creating an internal space through the step for the upper plate 510 to accommodate cooling water. Here, the width direction of the upper plate 510 can be a direction parallel to the short side of the upper plate 510.

[0051] A sealing pad 512 can be provided on the cooling member 500. FIG. 3 shows the back surface of the upper plate 510, that is, the surface of the upper plate 510 facing the lower plate 520, and the sealing pad 512 can be provided on the back surface of the upper plate 510 and located between the upper plate 510 and the lower plate 520. The sealing pad 512 can be located in the sealing portion 540 of the cooling member 500.

[0052] The sealing pad 512 can be manufactured from a flexible material with elastic force. Examples of the material used to manufacture the sealing pad 512 include silicone-based foam pads, acrylic-based foam pads, or urethane-based foam pads. When the upper plate 510 and the lower plate 520 are joined, the sealing pad 512 can be compressed by an external force to fill the gap existing between the upper plate 510 and the lower plate 520. The sealing pad 512 can prevent the cooling water inside the cooling member 500 from flowing out through the gap.

[0053] On the other hand, in FIG. 3, the upper plate 510 is shown with the aforementioned flow path forming groove 550 and the deformation prevention groove 560 formed therein. However, since the flow path forming groove 550 or the deformation prevention groove 560 can be formed through an additional process after the upper plate 510 and the lower plate 520 are joined, it is not necessary that the flow path forming groove 550 or the deformation prevention groove 560 must be pre-formed on the upper plate 510 provided during the manufacture of the cooling member 500.

[0054] Referring to FIG. 4, the lower plate 520 of the cooling member 500 can have a shape generally similar to that of the upper plate 510. The lower plate 520 is also provided in a plate shape, but its central portion can be formed to be recessed or indented to have a step with the peripheral portion. By having a recessed shape based on the cross-section in the width direction, the lower plate 520 can form an internal space for accommodating cooling water. Here, the width direction of the lower plate 520 can be a direction parallel to the short side of the lower plate 520.

[0055] When the cooling member 500 is provided on top of the battery cell, the lower plate 520 can be the portion of the cooling member 500 that is closest to the battery cell. Therefore, the lower plate 520 is preferably provided with a material having a high thermal conductivity so as to promote heat dissipation of the battery cell. Also, in order to improve the overall heat dissipation performance of the cooling member 500, the upper plate 510 of the cooling member 500 can also be provided with a material having a high thermal conductivity. The upper plate 510 and the lower plate 520 forming the outer shape of the cooling member 500 can be manufactured with a highly rigid metal, and specific examples thereof include aluminum, gold, silver, copper, platinum, or alloys containing these.

[0056] The lower plate 520 can be provided with one material, or can be provided with two or more types of materials. For example, the lower plate 520 can include a first portion 522 provided with a first material and a second portion 524 provided with a second material. Specifically, the lower plate 520 can be formed by removing a partial region from a plate-shaped member manufactured with a first material and then filling or fitting a member manufactured with a second material into the removed partial region. This can be such that when an internal ignition of the battery cell occurs, the second portion 524 of the lower plate 520 is opened by heat or pressure generated by the ignition. The second material provided for the second portion 524 can be more vulnerable to heat or pressure than the first material. When the second portion 524 is opened, the cooling water in the cooling member 500 can be sprayed onto the battery cell, so that the ignition phenomenon of the battery cell can be more rapidly alleviated. More specifically, the first material can be a metal such as aluminum, and the second material can be a thermoplastic polymer resin having a melting point of 200 °C or lower. Examples of the thermoplastic polymer resin include substances such as polyethylene and polypropylene having a melting point of about 100 °C or higher and 200 °C or lower.

[0057] On the other hand, as described above, even if the upper plate 510 or the lower plate 520 is manufactured with two or more types of materials, or the lower plate 520 is manufactured with one material, when the upper plate 510 is manufactured with a material different from that of the lower plate 520, two or more types of materials with different physical properties can be included in the cooling member 500. Conventionally, since the upper plate 510 and the lower plate 520 of the cooling member 500 were mainly joined by brazing or laser welding, etc., when designed such that two or more types of materials are included in the cooling member 500 in this way, one material can be deformed during the welding process, so there were problems such as the welding process becoming complicated or impossible. Also, when using laser welding or the like, a local temperature gradient can be formed in the upper plate 510 or the lower plate 520, and thus there was a problem that at least a part of the upper plate 510 or the lower plate 520 is bent.

[0058] However, since the cooling member 500 of the present embodiment is manufactured through a mechanical fastening method instead of a welding method, it can be manufactured to include two or more types of materials, which is different from the prior art. Specifically, the mechanical fastening method of the present embodiment can minimize damage to the material forming the cooling member 500 by not applying heat or applying heat at a temperature lower than the melting point of the material provided to the cooling member 500. Therefore, since various materials can be used for the cooling member 500 of the present embodiment regardless of the welding temperature, the design of the cooling member 500 can be made easier and more diverse.

[0059] Hereinafter, the mechanical fastening method applied to the cooling member 500 and the structural characteristics of the cooling member 500 manifested thereby will be described with reference to the drawings.

[0060] FIG. 5 is a drawing showing a cross-section taken along line A-A of the cooling member in FIG. 2. FIG. 6 is a drawing showing the process of forming the cross-sectional structure in FIG. 5. FIG. 7 is a partially enlarged view of the cooling member in FIG. 2.

[0061] The cooling member 500 of the present embodiment can be manufactured using a clinching fastening method. Clinching is a deformation joining method that mechanically joins two members by pressing one surface of two laminated plate-shaped members using a punch or the like to deform their shape. Clinching can also be referred to as penetration joining in consideration of its shape.

[0062] When manufacturing the cooling member 500, if the clinching fastening method is applied instead of the welding joining method, excessive heat will not be generated during the manufacturing process. Therefore, unintended deformation of the cooling member 500 can be minimized, and dimensional stability can be ensured by reducing the difference between the pre-designed dimensions and the dimensions of the final product. In particular, in the case of the aluminum material that has been mainly used for the cooling member 500, it can start to deform when a temperature of 660°C or higher, which is the melting point, is applied. However, if the above-described clinching fastening method is applied, since heat above the melting point is not applied to the cooling member 500, the dimensional stability of the cooling member 500 can be further improved.

[0063] In addition, if the clinching fastening method is applied during the manufacturing of the cooling member 500, specific materials that are vulnerable to temperature can be prevented from deforming during the manufacturing process, so that various materials and shapes of structures that can be formed by insert injection can be applied to the cooling member 500.

[0064] Referring to FIGS. 5 to 7, the sealing portion 540 of the cooling member 500 of the present embodiment can be formed through the aforementioned clinching fastening method. The sealing portion 540 can have an indented portion 542 that is indented in one direction. The indented portion 542 can be a portion that is integrally indented along the pressing direction when a part of the upper plate 510 or the lower plate 520 is pressed. By forming the indented portion 542 in the sealing portion 540, the upper plate 510 and the lower plate 520 can be physically coupled. Here, the pressing direction may be a direction from the upper plate 510 to the lower plate 520, or may be a direction from the lower plate 520 to the upper plate 510.

[0065] For a specific example, the two surfaces of the upper plate 510 can be referred to as the first surface and the second surface, and the two surfaces of the lower plate 520 can be referred to as the third surface and the fourth surface. Based on the first direction from the upper plate 510 to the lower plate 520, the first surface to the fourth surface can be positioned in the order of the first surface, the second surface, the third surface, and the fourth surface. The first surface of the upper plate 510 and the fourth surface of the lower plate 520 can form the outer surface of the cooling member 500, and the second surface of the upper plate 510 and the third surface of the lower plate 520 can face each other.

[0066] Here, when the first surface of the upper plate 510 is partially pressed, the first surface can be indented in the first direction so as to have a predetermined depth and be formed in a concave shape. Here, when the upper plate 510 is pressed, the lower plate 520 located below the upper plate 510 can be deformed together, and the upper plate 510 and the lower plate 520 can be integrally coupled by being physically deformed by the pressing. Here, when the lower plate 520 is used as a reference, the indented portion 542 can also be described as being formed in a protruding convex shape.

[0067] When referring to the photograph of FIG. 5, the upper plate 510 and the lower plate 520 are respectively recessed through pressurization. Here, the recessed portion formed in the upper plate may be referred to as the upper recessed portion 543, and the recessed portion formed in the lower plate 520 may be referred to as the lower recessed portion 544. When the upper plate 510 is pressurized, the upper recessed portion 543 is formed, and the lower recessed portion 544 may be formed by introducing the upper recessed portion 543 into the lower plate 520.

[0068] The recessed portion 542 becomes to have a depth value by being recessed, and the depth direction of the recessed portion 542 may be perpendicular to the direction in which the cooling water inside the cooling member 500 flows. Here, the depth direction may be the pressurization direction described above. By forming the recessed portion 542 to have a depth, the upper plate 510 and the lower plate 520 are firmly bonded to each other, and it can be prevented that the upper plate 510 and the lower plate 520 are slightly opened due to the pressure in the cooling member 500. Also, even when the upper plate 510 and the lower plate 520 are slightly opened, the recessed portion 542 can prevent the cooling water from flowing out of the cooling member 500 to the outside by obstructing the flow of the cooling water so that the cooling water does not exceed the sealing portion 540 where the recessed portion 542 is formed.

[0069] Here, the lowest point of the first surface where the recessed portion 542 is formed can be located below the highest point of the region where the recessed portion 542 is not formed, that is, the highest point of the third surface or the highest point of the fourth surface. When a part of the upper surface (the first surface) of the upper plate 510 is deformed to be located below the upper surface (the third surface) or the lower surface (the fourth surface) of the lower plate 520 through the clinching process in this way, the upper plate 510 is completely introduced into the lower plate 520, so that the connection between the upper plate 510 and the lower plate 520 can be formed more stably.

[0070] The depth of the recessed portion 542 may be greater than the thickness of the upper plate 510, the lower plate 520, or the combined thickness of these. If the depth of the recessed portion 542 is excessively small, it may be difficult to ensure watertightness between the upper plate 510 and the lower plate 520. If the depth of the recessed portion 542 is excessively large, the upper plate 510 and the lower plate 520 may be excessively deformed or partially cut. For example, when the sum of the thickness of the upper plate 510 and the lower plate 520 in the portion where the recessed portion 542 is not formed is 100, the depth of the recessed portion 542 can be 50 or more, or can have a value between 50 and 200. However, the above values are merely illustrative and do not limit the depth of the recessed portion 542 of the present invention. Here, the depth of the recessed portion 542 can be based on the upper recessed portion 543, and specifically can be the depth of the first surface of the upper recessed portion 543 based on the upper plate 510 where the recessed portion 542 is not formed.

[0071] The depth of the upper recessed portion 543 may be greater than the depth of the lower recessed portion 544. This may be because when pressurized along the first direction, the upper recessed portion 543 is located inside the recessed portion 542 relative to the lower recessed portion 544, so the upper recessed portion 543 forming the inner diameter has to be deformed more than the lower recessed portion 544 forming the outer diameter. During the process of forming the upper recessed portion 543 and the lower recessed portion 544 through the pressurization process, the pressurized upper plate 510 and lower plate 520 will have their thickness values decreased as the area increases, but the upper recessed portion 543 has to accommodate all the changes in the thickness of the upper plate 510 and the lower plate 520 and be deformed, so it can also be formed with a greater depth. On the other hand, the first direction is for illustrative purposes of the pressurization direction. When the upper plate 510 and the lower plate 520 are pressurized along the second direction opposite to the first direction, the lower recessed portion 544 will be located inside, so the depth of the lower recessed portion 544 can have a value greater than the depth of the upper recessed portion 543.

[0072] The recessed portion 542 can have a shape in which the end in the depth direction is somewhat widened. The lowermost end (the lowest end) of the upper recessed portion 543 can have a diameter somewhat larger than that of other portions of the upper recessed portion 543. The lowermost end (the lowest end) of the lower recessed portion 544 can have a diameter somewhat larger than that of other portions of the lower recessed portion 544. Here, the maximum value of the outer diameter of the upper recessed portion 543 may be larger than the minimum value of the inner diameter of the lower recessed portion 544, and for this reason, a locking connection can be formed between the upper recessed portion 543 and the lower recessed portion 544. Therefore, even if pressure acts between the upper recessed portion 543 and the lower recessed portion 544 due to the internal pressure of the cooling member 500, the upper plate 510 and the lower plate 520 cannot be opened due to the above-described locking connection. Thus, according to the shapes of the upper recessed portion 543 and the lower recessed portion 544, the coupling force of the recessed portion 542 can be further improved.

[0073] On the other hand, according to an embodiment, the punch can re-pressurize the recessed portion 542 so that the sealing portion 540 can be formed more completely. At this time, the punch can deform the recessed portion 542 so that the recessed portion 542 is stepped on, so that the upper plate 510 and the lower plate 520 can be more stably coupled. Through such re-pressurization, the recessed portion 542 can be deformed so as to be distorted or the depth of the recessed portion 542 can be reduced. At this time, the recessed portion 542 can be disposed between the punch and a second die having a recess with a diameter larger than that of the die, and when the punch pressurizes the recessed portion 542, the already formed recessed portion 542 is deformed to fit into the recess of the second die, so that at least a part of the recessed portion 542 can have a larger diameter.

[0074] Here, the fact that the upper bay-in part 543 and the lower bay-in part 544 have a shape with a somewhat widened end in the depth direction may be for the re-pressurization process by the second die. However, this is not necessarily the case, and even without using the second die, the upper bay-in part 543 and the lower bay-in part 544 can be formed to have the above-described shape by the operations of the punch and the die. Re-pressurizing the bay-in part 542 may cause damage to the bay-in part 542, so the above-described re-pressurization process must be applied considering the physical properties, size, etc. of the bay-in part 542.

[0075] The outer diameter of the bay-in part 542, that is, the outer diameter of the lower bay-in part 544, can have values of 5 to 11 mm, 7 to 9 mm, or 7.5 to 8.5 mm. If the diameter of the bay-in part 542 is excessively small, it may be difficult for the upper plate 510 and the lower plate 520 to be firmly joined by the bay-in part 542. If the diameter of the bay-in part 542 is excessively large, the deformation of the upper plate 510 and the lower plate 520 due to the bay-in part 542 may become excessive, and the dimensional stability of the cooling member 500 may decrease. Also, the diameter of the bay-in part 542 can be designed differently according to the distance between the bay-in parts 542, that is, the first interval described later.

[0076] At this time, since the diameter of the bay-in part 542 can vary depending on the diameter of the second die, the above-described outer diameter value of the lower bay-in part 544 can correspond to the recess inner diameter value of the second die. Also, when forming the bay-in part 542 and only one die is used without using the second die, the above-described outer diameter value of the lower bay-in part 544 can correspond to the recess inner diameter value of the die. That is, the above-described outer diameter value of the lower bay-in part 544 can correspond to the recess inner diameter value of the die finally used.

[0077] Also, in addition to the diameter of the bay-in part 542, the shape of the bay-in part 542 can be determined according to the shape of the punch, die, or second die used. For example, when the cross-section of the punch is circular, the bay-in part 542 can be formed as a whole in a tubular shape, and when the cross-section of the punch is square, the bay-in part 542 can be formed as a whole in a square tubular shape.

[0078] The above description was based on the case where the recessed portion 542 is formed by pressing the first surface in the first direction. However, this is an example of the formation of the recessed portion 542, and the recessed portion 542 can also be formed by pressing the fourth surface along the second direction. Even if the recessed portion 542 is formed by being pressed along the second direction, it can be sufficiently understood through the above-described content, and thus a detailed description thereof will be omitted.

[0079] On the other hand, in order to further improve the watertightness between the upper plate 510 and the lower plate 520, a sealing pad 512 can be positioned between the upper plate 510 and the lower plate 520. When applying the conventional welding connection method, it was difficult to provide the sealing pad 512, which is somewhat vulnerable to heat, during the connection of the upper plate 510 and the lower plate 520. Therefore, when using the welding process, in order to complement the watertightness of the welded surface, mainly after the connection of the upper plate 510 and the lower plate 520, a sealant or the like was applied through an additional process. However, since the cooling member 500 according to the present embodiment is formed through a mechanical connection method, the heat-vulnerable sealing pad 512 can be joined together during the joining process of the upper plate 510 and the lower plate 520, thereby achieving simplification of the manufacturing process and reduction of manufacturing costs.

[0080] The sealing pad 512 is provided between the second surface of the upper plate 510 and the third surface of the lower plate 520 facing each other, and the upper plate 510, the sealing pad 512, and the lower plate 520 can be arranged to be in surface contact with each other. As shown in FIG. 6, a punch can be positioned on one surface of the laminate in which the upper plate 510, the sealing pad 512, and the lower plate 520 are laminated along the first direction, and a die having a recess can be positioned on the other surface. Here, the recess provided in the die can be formed to correspond to the outer peripheral shape of the punch. After the laminate is disposed between the punch and the die, when the punch moves to press one surface of the laminate, the laminate is deformed until it abuts against the recessed portion of the die, and the recessed portion 542 is formed in the laminate having three layers by the above-described pressure, whereby the three layers can be firmly joined to each other.

[0081] Through the pressurization process described above, the sealing pad 512 provided by the elastic body can have its thickness reduced by being compressed. Specifically, based on the thickness of the sealing pad 512 without external force applied, the thickness of the sealing pad 512 appearing on the cross-section of the cooling member 500 can be 20% to 80%. At this time, the thickness of the sealing pad 512 can be compared based on the smallest value among the thicknesses of the sealing pad 512 appearing on the cross-section, or based on the average value of the thickness of the sealing pad 512. On the other hand, when the sealing pad 512 is compressed, the watertightness between the upper plate 510 and the lower plate 520 can be improved. In order to ensure the watertightness described above, it is preferable that the sealing pad 512 is compressed at 40% to 60%, or about 50%. Therefore, at least a part of the sealing pad 512 appearing on the cross-section of the cooling member 500 is preferably 40% to 60%, or about 50% or less based on the thickness of the sealing pad 512 without external force applied. The minimum value of the thickness of the sealing pad 512 is preferably 40% to 60%, or about 50% or less.

[0082] On the other hand, not only does the sealing pad 512 decrease through the pressurization process, but the thicknesses of the upper plate 510 and the lower plate 520 can also be partially deformed. The lowest point of the recessed portion 542 can be the portion that is pressurized by the punch and receives the greatest pressure. Therefore, the thickness value of the lowest point of the recessed portion 542, that is, the deepest recessed portion, may be smaller than the thicknesses of other portions. Before the recessed portion 542 is formed, the portion corresponding to the punch must form the side portion from the highest point to the lowest point of the recessed portion 542 by being pressed by the pressure of the punch. Therefore, the overall thickness may decrease as the area increases due to the pressure of the punch.

[0083] Referring to FIG. 7, a plurality of recessed portions 542 can be formed in the sealing portion 540, and the plurality of recessed portions 542 can be positioned at intervals. Specifically, in the sealing portion 540 formed with the first width w1, the adjacent recessed portions 542a and 542b can be positioned at the first distance p1. The first distance p1 can be an important variable for ensuring the watertightness of the sealing portion 540. Specifically, if the value of the first distance p1 is excessively small, the deformation due to pressurization may become excessive, and the dimensional stability of the cooling member 500 may decrease. If the value of the first distance p1 is excessively large, the firmness of the sealing portion 540 may decrease. Also, as described above, the first distance p1 can also affect the size value of the recessed portion 542. When the first distance p1 is designed to be large, it is preferable that the recessed portion 542 is formed larger than when the first distance p1 is designed to be small. Here, the first width w1 can also be the width value of the sealing pad 512. Also here, the first distance p1 can be referred to as a pitch.

[0084] FIG. 8 is a drawing showing a cross-section taken along the line B-B of the cooling member in FIG. 2. FIG. 9 is a drawing showing the process of forming the cross-sectional structure of FIG. 8.

[0085] Referring to FIGS. 8 and 9, the flow path forming groove 550 and the anti-deformation groove 560 of the cooling member 500 of the present embodiment can be formed through the above-described clinching fastening method. In the manufacturing method of the cooling member 500 applying the conventional welding connection method, a separate manufacturing process had to be added to form the flow path. However, since the mechanical connection method is applied to the cooling member 500 of the present embodiment, a separate manufacturing process for forming the flow path is omitted, and the flow paths can be formed together during the coupling process of the upper plate 510 and the lower plate 520 described in FIGS. 5 to 7. Also, within the same process, an anti-deformation structure can be formed in the cooling member 500 by forming the anti-deformation groove 560. Therefore, the cooling member 500 of the present embodiment applying the mechanical connection method can have advantages such as simplification of the manufacturing process and reduction of manufacturing costs compared to the case of using the conventional connection method.

[0086] Specifically, the flow path forming groove 550 or the anti-deformation groove 560 can be formed by pressing one surface of the separated upper plate 510 and lower plate 520. Since the flow path forming groove 550 or the anti-deformation groove 560 can be formed in the same manner as the aforementioned recessed portion 542 except that the sealing pad 512 is not provided, a detailed description thereof is omitted. Also, considering the manufacturing process and shape of the flow path forming groove 550 and the anti-deformation groove 560, they can be referred to as "recessed portions". At this time, the recessed portion 542 formed in the sealing portion 540 can be referred to as the first recessed portion, the flow path forming groove 550 as the second recessed portion, and the anti-deformation groove 560 as the third recessed portion.

[0087] Here, since the flow path forming groove 550 or the anti-deformation groove 560 is also formed by deforming both the upper plate 510 and the lower plate 520 together, an upper flow path forming groove and a lower flow path forming groove can be formed in the upper plate 510 and the lower plate 520 respectively through the flow path forming groove 550, and an upper anti-deformation groove and a lower anti-deformation groove can be formed in the upper plate 510 and the lower plate 520 respectively through the anti-deformation groove 560. Therefore, since the content regarding the depth, diameter, etc. of each deformed part can be specifically described through the aforementioned content, a detailed description thereof is omitted.

[0088] However, since the recessed portion 542 in FIGS. 5 to 7 is formed by pressing the peripheral edges of the upper plate 510 and the lower plate 520 that are in contact with each other or in contact through the sealing pad 512, the upper plate 510 and the lower plate 520 are integrally joined through the formation of the recessed portion 542. However, since the flow path forming groove 550 and the anti-deformation groove 560 are formed by pressing the central or inner portions of the upper plate 510 and the lower plate 520 that are separated from each other, the central or inner portions of the upper plate 510 and the lower plate 520 are not joined as firmly as the recessed portion 542 by the flow path forming groove 550 or the anti-deformation groove 560. For example, the depth of the recessed portion 542 formed at the peripheral portion of the upper plate 510 and the lower plate 520 can have a value larger than the depth of the flow path forming groove 550 and the anti-deformation groove 560 formed at the central or inner portions of the upper plate 510 and the lower plate 520.

[0089] However, since the channel forming groove 550 requires a stronger bond between the upper plate 510 and the lower plate 520 than the deformation prevention groove 560, a long groove extending in the length direction of the cooling member 500 is pre-formed, and by forming the channel forming grooves 550 at intervals in the long groove, the bonding level can also be complemented. By pre-forming a long groove extending in the length direction of the cooling member 500 in the upper plate 510 or the lower plate 520, the upper plate 510 and the lower plate 520 can partially contact each other. Since the channel forming groove 550 is formed by locally pressing two plates in contact with each other, the channel forming groove 550 can mechanically and firmly join the upper plate 510 and the lower plate 520, similar to the case of the recessed portion 542. Here, in the cooling member 500, the upper plate 510, or the lower plate 520, the central portion or the inner portion means a portion excluding the periphery and can be a portion where the cooling water is built-in or circulated.

[0090] Hereinafter, a method for manufacturing a cooling member using a mechanical fastening method will be described.

[0091] FIG. 10 is a flowchart showing a method for manufacturing a cooling member according to another embodiment of the present invention.

[0092] Referring to FIG. 10, the method for manufacturing a cooling member (S1000) can include a step of providing an upper plate 510 (S1100), a step of positioning a sealing pad 512 on the upper plate 510 (S1200), a step of joining the upper plate 510 and the lower plate 520 with the sealing pad 512 interposed therebetween (S1300), a step of forming a cooling channel (S1400), and a step of forming a deformation prevention structure (S1500).

[0093] Hereinafter, each step will be described in more detail.

[0094] The step of providing the upper plate 510 (S1100) may mean that the manufactured upper plate 510 is prepared for the manufacturing process of the present embodiment. Here, the upper plate 510 can have a shape in which the central portion is recessed more than the peripheral portion. A groove may be provided partially in the central portion of the upper plate 510. Also here, the lower plate 520 can have a shape in which the central portion is recessed more than the peripheral portion. The lower plate 520 can include a first portion having a first material and a second portion having a second material. At least a part of the lower plate 520 can be formed through insert injection.

[0095] The step of positioning the sealing pad 512 on the upper plate 510 (S1200) can include the step of closely attaching the sealing pad 512 to the back surface (lower surface) of the upper plate 510 as shown in FIG. 3. Since this can be explained through FIG. 3, a specific explanation thereof is omitted in the present embodiment.

[0096] Also, the step of positioning the sealing pad 512 on the upper plate 510 (S1200) can include the step of laminating the upper plate 510 and the lower plate 520 with the sealing pad 512 positioned thereon after the step of closely attaching the sealing pad 512 to the back surface (lower surface) of the upper plate 510. The step can be a step of placing the upper plate 510 and the sealing pad 512 on the lower plate 520. Here, the upper plate 510 and the lower plate 520 having similar outer shapes to each other can be arranged such that the back surface of the upper plate 510 and the upper surface of the lower plate 520 face each other, and the peripheries of each other where the sealing pad 512 is positioned can be arranged to correspond to each other.

[0097] The step of joining the upper plate 510 and the lower plate 520 with the sealing pad 512 interposed therebetween (S1300), the step of forming a cooling flow path (S1400), and the step of forming a deformation prevention structure (S1500) can be performed through the clinching process described above.

[0098] Specifically, a pair of punching and die can be used in the clinching process. The die can have a recess formed with a shape corresponding to the outer shape of the punching. If a workpiece is positioned between the punching and the die, a part of the workpiece can be deformed to fit the shapes of the punching and the recess of the die as the punching moves toward the die. When the workpiece is composed of two or more layers, the two or more layers can be mechanically joined through the above-described deformation.

[0099] The punch and the die can join an upper plate 510 and a lower plate 520 with a sealing pad 512 interposed therebetween (S1300). By forming an indentation portion 542 through the operations of the punch and the die, a sealing portion 540 is formed on the upper plate 510 and the lower plate 520, whereby the upper plate 510 and the lower plate 520 can be joined. By forming the indentation portion 542, the peripheral portions of the upper plate 510 and the lower plate 520 can be joined. By forming the indentation portion 542, the upper plate 510, the sealing pad 512, and the lower plate 520 laminated on each other can be joined.

[0100] The step of joining the upper plate 510 and the lower plate 520 with the sealing pad 512 interposed therebetween (S1300) can include the steps of preparing a laminate in which the upper plate 510, the sealing pad 512, and the lower plate 520 are laminated in this order, aligning the laminate with the die, advancing the punch toward the laminate, locally pressing the laminate with the punch so that the laminate is deformed according to the recess shape of the die, and retracting the punch away from the laminate.

[0101] Here, the step (S1300) of joining the upper plate 510 and the lower plate 520 with the sealing pad 512 interposed therebetween can further include a step of retracting the punch away from the laminate, a step of aligning the laminate with the second die, a step of advancing the punch toward the laminate, a step of locally pressing a deformed part (the recessed part) of the laminate by the punch so that the deformed part (the recessed part) of the laminate is deformed according to the recess shape of the second die, and a step of retracting the punch away from the laminate. At this time, in the step of aligning the laminate with the second die, the part of the laminate corresponding to the second die can be the recessed part 542 formed through the above-described steps.

[0102] On the other hand, by repeating the above-described steps, at least two or more recessed parts 542 can be formed in the sealing part 540 of the upper plate 510 and the lower plate 520, and by forming a plurality of recessed parts 542, the connection between the upper plate 510 and the lower plate 520 can be made stronger.

[0103] The punch and the die can form a cooling flow path (S1400). By forming the flow path forming groove 550 through the operation of the punch and the die, a flow path can be formed in the central part of the upper plate 510 and the lower plate 520. By forming the flow path forming groove 550 to have a depth, a partition wall can be formed between the upper plate 510 and the lower plate 520. The partition wall can cross the internal space of the cooling member 500 so as to be perpendicular to the direction in which the cooling water inside the cooling member 500 flows, and the partition wall can obstruct the flow of the cooling water moving in the internal space.

[0104] The step (S1400) of forming the cooling flow path can include a step of preparing the upper plate 510 and the lower plate 520, a step of aligning the upper plate 510 and the lower plate 520 with the die, a step of advancing the punch toward one surface of the upper plate 510 and the lower plate 520, a step of locally pressing the upper plate 510 and the lower plate 520 by the punch so that the upper plate 510 and the lower plate 520 are deformed according to the recess shape of the die, and a step of retracting the punch away from the upper plate 510 and the lower plate 520.

[0105] Here, in the step of forming the cooling channel (S1400), after the step of retracting the punch, by realigning the upper plate 510 and the lower plate 520 in the second die alignment, the already formed channel forming groove 550 can also be repressurized. Since the specific steps regarding this can be described through the content of the aforementioned S1300 step, specific mention is omitted.

[0106] Also here, the upper plate 510 or the lower plate 520 provided in the step of forming the cooling channel (S1400) may be in a state where long grooves extending in the length direction are formed. Therefore, the step of forming the cooling channel (S1400) or the step of providing the upper plate 510 (S1100) can further include the step of forming long grooves extending in the length direction in the upper plate 510 or the lower plate 520. Since the description of the long grooves can be described with reference to the content regarding the channel forming groove 550, specific mention is omitted.

[0107] On the other hand, by repeating the aforementioned steps, at least two or more channel forming grooves 550 can be formed. If there are pre-formed long grooves, the channel forming grooves 550 can be continuously formed along the long grooves.

[0108] The punch and the die can form a deformation prevention structure (S1500). By forming the deformation prevention groove 560 through the operation of the punch and the die, a deformation prevention structure can be formed in the central portions of the upper plate 510 and the lower plate 520. The deformation prevention groove 560 is formed to have a depth, and for this purpose, a partition wall can be formed between the upper plate 510 and the lower plate 520. The partition wall can cross the internal space of the cooling member 500 so as to be perpendicular to the direction in which the cooling water inside the cooling member 500 flows. Therefore, even when an excessive amount of cooling water is injected into the internal space, the deformation of the cooling member 500 can be somewhat prevented.

[0109] The step of forming the anti-deformation structure (S1500) may include the steps of preparing the upper plate 510 and the lower plate 520, aligning the upper plate 510 and the lower plate 520 with the die, advancing the punch toward one surface of the upper plate 510 and the lower plate 520, locally pressing the upper plate 510 and the lower plate 520 by the punch so that the upper plate 510 and the lower plate 520 are deformed according to the recess shape of the die, and retracting the punch away from the upper plate 510 and the lower plate 520.

[0110] Here, in the step of forming the anti-deformation structure (S1500), after the step of retracting the punch, the formed anti-deformation groove 560 can be re-pressed by aligning the upper plate 510 and the lower plate 520 with the second die. Since the specific steps regarding this can be described through the content of the above-mentioned S1300 step, specific mention is omitted.

[0111] On the other hand, by repeating the above-mentioned steps, at least two or more anti-deformation grooves 560 can be formed. The anti-deformation groove 560 can be located between the sealing portion 540 and the flow path forming groove 550 in the width direction of the cooling member 500. The specific position of the anti-deformation groove 560 can be appropriately designed so as to correspond to the flow rate and flow velocity of the cooling water while not overly obstructing the cooling water flowing in through the inlet port 530.

[0112] Hereinafter, a battery pack including the above-mentioned cooling member will be described.

[0113] FIG. 11 is an exploded perspective view showing a battery pack according to another embodiment of the present invention. FIG. 12 is a perspective view of a battery module included in the battery pack according to FIG. 11.

[0114] Referring to FIG. 11, a battery pack 1000 according to an embodiment of the present invention can include at least one battery module 100, a pack frame 200 that houses the battery module 100, a resin layer 300 formed on the inner surface of the pack frame 200, an end plate 400 that closes the open surface of the pack frame 200, and a cooling member 500 disposed between the pack frame 200 and the battery cell stack 120. However, the components included in the battery pack 1000 are not limited to this, and depending on the design, the battery pack 1000 can be provided with some of the aforementioned components omitted, or can be provided with other components not mentioned added.

[0115] Referring to FIGS. 11 and 12, the battery module 100 provided in this embodiment can have a module-less structure in which the module frame is omitted.

[0116] Normally, a conventional battery pack has a double-assembly structure in which a battery cell stack and a number of components connected thereto are assembled to form a battery module, and a plurality of battery modules are again housed in the battery pack. At this time, since the battery module includes a module frame that forms its outer surface, etc., a conventional battery cell is doubly protected by the module frame of the battery module and the pack frame of the battery pack. However, such a double-assembly structure not only increases the manufacturing cost and manufacturing process of the battery pack, but also has the disadvantage that the reassembly performance deteriorates when a defect occurs in some battery cells. Also, when a cooling member or the like exists outside the battery module, there is a problem that the heat transfer path between the battery cell and the cooling member becomes somewhat complicated.

[0117] Therefore, the battery module 100 of the present embodiment can be provided in the form of a "cell block" in which the module frame is omitted, and the battery cell stack 120 included in the cell block can be directly coupled to the pack frame 200 of the battery pack 1000. As a result, the structure of the battery pack 1000 becomes simpler, and advantages in manufacturing cost and manufacturing process can be obtained, and the weight reduction of the battery pack can be achieved.

[0118] Hereinafter, the battery module 100 without a module frame may be referred to as a "cell block" for the purpose of distinction from a battery module having a module frame. However, the battery module 100 should be interpreted as including both a normal battery module having a module frame and a cell block, as a general term for those having a battery cell stack 120 segmented in a predetermined unit for modularization regardless of the presence or absence of a module frame.

[0119] Referring to FIG. 12, the battery module 100 of the present embodiment may include a battery cell stack 120 in which a plurality of battery cells 110 are stacked along one direction, side plates 130 positioned at both ends in the stacking direction of the battery cell stack 120, a holding strap 140 surrounding the side plates 130 and the battery cell stack 120 to fix its form, and a bus bar frame 150 covering the front and rear surfaces of the battery cell stack 120.

[0120] On the other hand, although FIG. 12 shows the battery module 100 provided in the form of a cell block, the content of such a drawing does not exclude the case where a sealed battery module 100 having a module frame is applied to the battery pack 1000 of the present embodiment.

[0121] The battery cell 110 can include an electrode assembly, a cell case, and an electrode lead protruding from the electrode assembly, respectively. The battery cell 110 can be provided in a pouch type or a rectangular type that can maximize the number of laminations per unit area. For example, the battery cell 110 provided in a pouch type can be manufactured by housing an electrode assembly including a positive electrode, a negative electrode, and a separator in a cell case of a laminate sheet and then heat-sealing the sealing portion of the cell case. On the other hand, in FIGS. 11 and 12, the positive electrode lead and the negative electrode lead of the battery cell 110 are shown protruding in opposite directions from each other, but this is not necessarily the case, and the electrode leads of the battery cell 110 can also protrude in the same direction.

[0122] The battery cell stack 120 can be a stack of a plurality of electrically connected battery cells 110 along one direction. The direction in which the plurality of battery cells 110 are stacked (hereinafter referred to as the "stacking direction") can be the y-axis direction (or the -y-axis direction, and hereinafter, the expression "axial direction" can be interpreted to include all + / - directions) as shown in FIGS. 11 and 12.

[0123] On the other hand, by arranging the battery cells 110 along one direction, the electrode leads of the battery cells 110 can be located on one surface of the battery cell stack 120, or one surface and the other surface facing the one surface. In this way, the surface on which the electrode leads are located in the battery cell stack 120 can be referred to as the front surface or the rear surface of the battery cell stack 120, and the front surface and the rear surface of the battery cell stack 120 are shown as two surfaces facing each other on the x-axis in FIGS. 11 and 12.

[0124] In addition, the surface on which the outermost battery cell 110 is located in the battery cell stack 120 can be referred to as the side surface of the battery cell stack 120, and the side surfaces of the battery cell stack 120 are shown as two surfaces facing each other on the y-axis in FIGS. 11 and 12.

[0125] The side plate 130 may be provided to maintain the overall shape of the battery cell stack 120. As a plate-shaped member, the side plate 130 can complement the rigidity of the cell block instead of the module frame. The side plate 130 may be disposed at both ends in the stacking direction of the battery cell stack 120 and can contact the outermost battery cells 110 on both sides of the battery cell stack 120.

[0126] The side plate 130 can be manufactured from various materials and provided through various manufacturing methods. As an example, the side plate 130 can be a plastic material manufactured by injection molding. As another example, the side plate 130 can be manufactured from a leaf spring material. As still another example, the side plate 130 can be manufactured from an elastic material so that its shape can be partially deformed in response to the volume change of the battery cell stack 120 due to swelling.

[0127] The holding strap 140 may be for fixing the positions and forms of the side plates 130 at both side ends of the battery cell stack 120. The holding strap 140 can be a member having a length and a width. Specifically, the battery cell stack 120 can be positioned between two side plates 130 that contact the outermost battery cells 110, and the holding strap 140 can connect the two side plates 130 across the battery cell stack 120. Thereby, the holding strap 140 can prevent the distance between the two side plates 130 from increasing beyond a certain range, so that the overall shape of the cell block can be maintained within a certain range.

[0128] The holding strap 140 can have locking portions at both ends in its length direction for stable connection with the side plate 130. The locking portions can be formed by bending both ends in the length direction of the holding strap 140. On the other hand, locking grooves are formed at positions corresponding to the locking portions on the side plate 130, and the holding strap 140 and the side plate 130 can be stably connected through the connection between the locking portions and the locking grooves.

[0129] The holding strap 140 can be provided through various materials or various manufacturing methods. As an example, the holding strap 140 can be manufactured from an elastic material, thereby allowing the volume change of the battery cell stack 120 due to swelling to be within a certain range.

[0130] On the other hand, the holding strap 140 is for fixing the relative position between the side plate 130 and the battery cell stack 120, and if its purpose as a "fixing member" is achieved, it can be provided in a form different from that shown. For example, the fixing member can be provided in the form of a long bolt that can cross between the two side plates 130, that is, a long bolt. The side plate 130 is provided with a groove into which the long bolt can be inserted, and the long bolt can fix the relative position of the two side plates 130 by simultaneously connecting to the two side plates 130 through the groove. The long bolt can be provided at the periphery of the side plate 130, preferably at a position close to the apex of the side plate 130. By design, it is also possible for the holding strap 140 to be replaced by the aforementioned long bolt, but it is also possible for both the holding strap 140 and the long bolt to be provided in the cell block.

[0131] The bus bar frame 150 can be located on one surface of the battery cell stack 120 to cover one surface of the battery cell stack 120 and at the same time guide the connection between the battery cell stack 120 and an external device. The bus bar frame 150 can be located on the front or rear surface of the battery cell stack 120. Two bus bar frames 150 can be provided so as to be located on the front and rear surfaces of the battery cell stack 120. A bus bar is mounted on the bus bar frame 150, and thereby the electrode leads of the battery cell stack 120 can be connected to the bus bar, whereby the battery cell stack 120 can be electrically connected to an external device.

[0132] The bus bar frame 150 can include a material that is electrically insulating. The bus bar frame 150 can limit contact between other parts of the battery cell 110 except for the part where the bus bar is joined to the electrode lead, and can prevent an electrical short circuit from occurring.

[0133] The pack frame 200 can be for protecting the battery module 100 and electrical components connected thereto from external physical impacts. The pack frame 200 can house the battery module 100 and electrical components connected thereto in the internal space of the pack frame 200. Here, the pack frame 200 includes an inner surface and an outer surface, and the internal space of the pack frame 200 can be defined by the inner surface.

[0134] There can be a plurality of battery modules 100 housed in the pack frame 200. The plurality of battery modules 100 can be referred to as a “module assembly”. The module assembly can be arranged in rows and columns within the pack frame 200. Here, “row” means a set of battery modules 100 arranged in one direction, and “column” can mean a set of battery modules 100 arranged in a direction perpendicular to the one direction. For example, the battery modules 100 can be arranged along the stacking direction of the battery cell laminate as shown in FIG. 12 to form one row or column to form a module assembly.

[0135] The pack frame 200 can be provided in a hollow form that is open along one direction. For example, as shown in FIG. 12, a plurality of battery modules 100 are continuously positioned along the stacking direction of the battery cells 110, and the pack frame 200 can have a hollow form that is open along the aforementioned stacking direction.

[0136] The structure of the pack frame 200 can be diverse. As an example, as shown in FIG. 11, the pack frame 200 can include a lower frame 210 and an upper frame 220. Here, the lower frame 210 is provided in a plate shape, and the upper frame 220 can be provided in a U shape. At least one battery module 100 is disposed on the plate-shaped lower frame 210, and the U-shaped upper frame 220 can be provided so as to surround the upper surface of the module assembly and two surfaces on the x-axis.

[0137] The pack frame 200 can include portions with high thermal conductivity to quickly release heat generated in the internal space to the outside. For example, at least a part of the pack frame 200 is made of a metal with high thermal conductivity, and examples thereof can include aluminum, gold, silver, copper, platinum, or alloys containing these. Also, the pack frame 200 can be partially electrically insulating, and an insulating film can be provided or an insulating coating can be applied at positions where insulation is required. The portions where the insulating film or insulating coating is applied in the pack frame 200 can be referred to as insulating portions.

[0138] A resin layer 300 can be provided between the battery module 100 and the inner surface of the pack frame 200. The resin layer 300 can be provided between the bottom surface of the battery module 100 and the lower frame 210. The resin layer 300 can be provided between the upper surface of the battery module 100 and the upper frame 220. Here, specifically, the resin layer 300 can be provided between the cooling member 500 described later and the upper frame 220.

[0139] The resin layer 300 can be formed by injecting resin between the battery cell laminate 120 and one side surface of the inner surface of the pack frame 200. However, this is not necessarily the case, and the resin layer 300 can also be a member provided in a plate shape.

[0140] The resin layer 300 is manufactured from various substances, and the functions of the resin layer 300 can vary depending on the substance. For example, the resin layer 300 is formed of an insulating substance, and electron transfer between the battery module 100 and the pack frame 200 can be prevented through the insulating resin layer 300. As another example, the resin layer 300 can be formed of a heat-conductive substance. The resin layer 300 manufactured from a heat-conductive substance can transfer the heat generated in the battery cell 110 to the pack frame 200, so that the heat can be released / transferred to the outside. As still another example, the resin layer 300 can include an adhesive substance, whereby the battery module 100 and the pack frame can be fixed to each other. As a specific example, the resin layer 300 can be provided to include at least one of a silicone-based material, a urethane-based material, and an acrylic-based material.

[0141] The end plate 400 can be for protecting the battery module 100 and the electrical components connected thereto from external physical impacts by sealing the open surface of the pack frame 200. Each edge of the end plate 400 can be joined to the corresponding edge of the pack frame 200 by a method such as welding. Two end plates 400 can be provided to seal the two open sides of the pack frame 200 and can be manufactured from a metallic substance having a predetermined strength.

[0142] An opening 410 can be formed in the end plate 400 to expose the inlet / outlet port 530 of the cooling member 500 described later, and a connector 420 for LV (Low voltage) connection or HV (High voltage) connection with an external device can be mounted.

[0143] The cooling member 500 can be for cooling the interior of the battery pack 1000 by releasing the heat generated from the battery cell 110. For the description of the cooling member 500, refer to the content described above.

[0144] On the one hand, although FIG. 11 shows that the cooling member 500 is provided outside the battery module 100, this is not necessarily the case, and the cooling member 500 can also be arranged inside the battery module 100. At this time, the battery module 100 may have a closed structure or an open structure such as a cell block.

[0145] On the other hand, although not specifically mentioned above, the battery pack according to an embodiment of the present invention can additionally include a battery management system (BMS) for managing the temperature, voltage, etc. of the battery and / or a cooling device.

[0146] The battery pack according to an embodiment of the present invention can be applied to various devices. For example, the devices to which the battery pack is applied can be means of transportation such as electric bicycles, electric vehicles, and hybrid vehicles. However, the above-mentioned devices are not limited to this, and the battery pack according to this embodiment can be used for various devices other than the above-mentioned examples, which also belongs to the scope of the rights of the present invention.

[0147] Although the preferred embodiments of the present invention have been described in detail above, the scope of the rights of the present invention is not limited thereto, and various modifications and improvements made by those skilled in the art using the basic concept of the present invention defined in the claims also belong to the scope of the rights of the present invention.

Description of Reference Numerals

[0148] 100: Battery module 110: Battery cell 120: Battery cell stack 130: Side plate 140: Holding strap 150: Bus bar frame 200: Pack frame 300: Resin layer 400: End plate 500: Cooling member 510: Upper plate 520: Lower plate 530: Inlet / Outlet Port 540: Sealing Part 542: Indented Part 550: Flow Path Forming Groove 560: Deformation Prevention Groove

Claims

1. In a cooling member for cooling a battery cell, including an upper plate, a lower plate, and an in-out port for injecting cooling water into an internal space between the upper plate and the lower plate, the cooling member includes a recessed portion formed by introducing the upper plate into the lower plate, a first recessed portion is formed at a peripheral portion of the cooling member, a second recessed portion is formed at a central portion of the cooling member, a sealing pad is positioned between the upper plate and the lower plate forming the first recessed portion, the recessed portion includes an upper recessed portion where the upper plate is deformed and a lower recessed portion where the lower plate is deformed, the lowest point of the upper surface of the upper recessed portion is located below the upper surface of the lower plate where the recessed portion is not formed, cooling member.

2. The recessed portion has a depth, and the direction in which the depth extends is perpendicular to the flow direction of the cooling water inside the cooling member, The cooling member according to Claim 1.

3. The lowest point of the upper surface of the upper recessed portion is located below the lower surface of the lower plate where the recessed portion is not formed, The cooling member according to Claim 1.

4. The recessed portion includes an upper recessed portion where the upper plate is deformed and a lower recessed portion where the lower plate is deformed, the maximum value of the outer diameter of the upper recessed portion is larger than the minimum value of the inner diameter of the lower recessed portion, The cooling member according to Claim 1 or 2.

5. The second recessed portion is formed in an elongated groove formed along the length direction of the cooling member, The cooling member according to Claim 1 or 2.

6. The recessed portion includes a third recessed portion located between the first recessed portion and the second recessed portion in the width direction of the cooling member, The cooling member according to Claim 1 or 2.

7. In a cooling member for cooling a battery cell, including an upper plate, a lower plate, and an in-out port for injecting cooling water into an internal space between the upper plate and the lower plate, the cooling member includes a recessed portion formed by introducing the upper plate into the lower plate or introducing the lower plate into the upper plate, a first recessed portion is formed at a peripheral portion of the cooling member, a second recessed portion is formed at a central portion of the cooling member, a sealing pad is positioned between the upper plate and the lower plate forming the first recessed portion, the lower plate includes a first portion formed of a first material and a second portion formed of a second material different from the first material, cooling member.

8. The first material is aluminum, The second material is a thermoplastic polymer resin having a melting point of 200°C or lower, The cooling member according to claim 7.

9. A method for manufacturing a cooling member for cooling a battery cell, Positioning a sealing pad at the periphery of the upper plate, Stacking the upper plate on which the sealing pad is located and a lower plate, By introducing the upper plate into the lower plate, forming a first recessed portion that joins the peripheral portions of the upper plate and the lower plate with the sealing pad therebetween, and a second recessed portion at the central portion of the upper plate and the lower plate, Including the step of arranging in-and-out ports for injecting cooling water into a cooling flow path formed between the upper plate and the lower plate, The lowest point on the upper surface of the deformed upper recessed portion of the upper plate is located below the upper surface of the deformed lower recessed portion of the lower plate, A method for manufacturing a cooling member.

10. Further including the step of forming a deformation prevention structure at the central portion of the upper plate and the lower plate by forming a third recessed portion, The method for manufacturing a cooling member according to claim 9.

11. The step of forming a first recessed portion that joins the peripheral portions of the upper plate and the lower plate Preparing a laminate in which the upper plate, the sealing pad, and the lower plate are stacked in this order, Aligning the laminate with a die, Advancing a punch toward the laminate, The step of locally pressurizing the laminate by the punch so that the laminate deforms according to the recessed shape of the die, and Including the step of retracting the punch away from the laminate, The method for manufacturing a cooling member according to claim 9 or 10.

12. After the step of retracting the punch away from the laminate, Including the step of aligning the laminate with a second die, The method for manufacturing a cooling member according to claim 11.

13. A battery module including the cooling member according to claim 1 or 2.

14. A battery pack including the cooling member according to claim 1 or 2.

15. The battery pack includes a battery module having an open structure, The battery pack according to claim 14.

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