Battery pack

Abstract

The present invention relates to a battery pack including: a plurality of battery units, each including a battery cell stack, and each having a terminal portion electrically connected to the battery cell stack on a front surface of the battery unit; a pack housing having a battery unit mounting area and partition members dividing the battery unit mounting area into a plurality of areas, the battery units being accommodated in the battery unit mounting area between the partition members; and a cover plate assembly covering upper and front surfaces of the battery units and coupled to the partition members.

Description

Technical Field

[0001] The present invention relates to a battery pack for accommodating battery units such as battery modules.

[0002] More specifically, the present invention relates to a battery pack capable of preventing the propagation of sparks and flames to adjacent battery units when ignition occurs within a battery unit.

[0003] This application claims the benefit of priority based on Korean Patent Application No. 10-2022-0120400 filed on September 23, 2022, and all the contents disclosed in the document of the Korean patent application are included as part of this specification.

Background Art

[0004] A battery pack applied to an electric vehicle or the like has a structure in which a number of battery modules including a plurality of secondary batteries are connected in series or in parallel to obtain high output. The secondary battery can be repeatedly charged and discharged by an electrochemical reaction between components including a positive electrode and a negative electrode current collector, a separator, an active material, an electrolyte, and the like.

[0005] FIG. 1 is a schematic view showing an example of a conventional battery pack 1.

[0006] In FIG. 1, the upper cover of the battery pack 1 is omitted for the sake of illustration. As shown in the figure, a plurality of battery modules 10 are arranged in a pack housing. In the battery pack 1 of FIG. 1, a plurality of battery modules 10 are arranged on the left and right around a central center frame. A terminal portion 12 such as a terminal bus bar is provided on the front surface of the battery module 10, and the terminal portions 12 of each battery module are connected in series or in parallel to electrically connect the battery modules.

[0007] If a thermal runway occurs in a battery cell within any one battery module, the heat will spread to adjacent battery cells, resulting in sparks or flames erupting from all sides of that battery module. In this case, battery modules adjacent to the module from which flames are erupting will also be exposed to the flames, potentially leading to a series of explosions in the battery module.

[0008] Since the base plate of the pack housing, which has a heat sink or cooling channel, is located at the bottom of the battery module, flame propagation can be suppressed relatively easily.

[0009] However, as shown in Figure 1, a space is formed between the top of the battery module and the upper cover (not shown), so flames can erupt from this upper space. In particular, the front of the module where the terminals of the battery module are installed is prone to overheating and ignition. Furthermore, the front of the module is vulnerable to ignition, as it can be electrically short-circuited when flames occur. Also, since the terminals are installed on the front of the battery module, electrical insulation is necessary.

[0010] Therefore, there is a need for the development of technology that can simultaneously protect the top and front of battery units, such as battery modules, from flames and sparks. [Prior art documents] [Patent Documents]

[0011] [Patent Document 1] Korean Published Patent No. 10-2021-0134165 [Overview of the project] [Problems that the invention aims to solve]

[0012] The present invention aims to solve the above-mentioned problems and provides a battery pack that can prevent sparks and flames from spreading to adjacent battery units by simultaneously covering the top and front surfaces of battery units such as battery modules. [Means for solving the problem]

[0013] To solve the above problems, a battery pack according to one embodiment of the present invention includes a plurality of battery units, each including a battery cell stack and each having a terminal portion on the front surface of the battery unit that is electrically connected to the battery cell stack; a battery unit mounting area; a pack housing having partition wall members that divide the battery unit mounting area into a plurality of sections, with each battery unit housed in the battery unit mounting area between the partition wall members; and a cover plate assembly that covers the top and front surfaces of the battery units and is coupled to the partition wall members.

[0014] The above-mentioned battery unit may be a battery module including a module case that houses a stack of battery cells and end plates that are connected to the front and rear surfaces of the module case.

[0015] The above-mentioned battery unit is a cell block with a moduleless structure in which busbar assemblies are attached to the front and rear surfaces of a battery cell stack, and all or part of the module case that houses the battery cell stack is absent, and the busbar assembly attached to the front surface of the battery cell stack may be provided with terminals.

[0016] The above-described moduleless cell block may have side support plates attached to both sides of the battery cell stack, and both the top and bottom surfaces of the battery cell stack may be open, except for the surface where the side support plates and the busbar assembly are attached.

[0017] The pack housing includes a center frame extending across the battery unit mounting area, with a plurality of partition members arranged on both sides of the center frame perpendicular to the extension direction of the center frame, and the battery units can be positioned between the partition members such that the front surfaces of the battery units face toward the center frame.

[0018] Multiple cover plate assemblies are provided to correspond to the number of battery units, with each cover plate assembly covering each battery unit and potentially being connected to a partition wall member.

[0019] The cover plate assembly described above may include a top cover plate that covers the top surface of the battery unit, and a front cover plate that is perpendicularly connected to one end of the top cover plate and covers the front surface of the battery unit.

[0020] Multiple fastening parts protrude at intervals along both sides of the upper cover plate, and these fastening parts can be connected to the upper surface of the partition member.

[0021] By positioning the fastening portions on the sides of the upper cover plates of adjacent cover plate assemblies to interlock with the spacing between the fastening portions on the sides of the upper cover plates of one cover plate assembly, the fastening portions of the upper cover plates of adjacent cover plate assemblies can be joined to the same partition member.

[0022] The above-mentioned front cover plate may be formed from an electrical insulating material.

[0023] The cover plate assembly further includes a rear cover plate which is perpendicularly connected to the other end of the upper cover plate and covers the rear surface of the battery unit, and a plurality of venting holes may be formed in the rear cover plate.

[0024] As another aspect of the present invention, a battery pack includes a plurality of cell blocks each including a battery cell laminate, a bus bar assembly coupled to the front surface of the battery cell laminate, and side support plates coupled to both side surfaces of the battery cell laminate, a pack housing having a cell block mounting area, in which the plurality of cell blocks are fixedly installed, and a cover plate assembly covering the upper and front surfaces of the cell blocks and coupled to the cell blocks.

[0025] The pack housing includes a center frame extending across the cell block mounting area, and the plurality of cell blocks may be arranged perpendicular to the extension direction of the center frame and with the front surfaces of the cell blocks facing the center frame respectively.

[0026] The side support plates are composed of a first side support plate coupled to one side surface of the battery cell laminate and a second side support plate coupled to the other side surface. The first side support plate and the second side support plate have complementary structures that mesh with each other. The first side support plate of one battery cell laminate and the second side support plate of the other battery cell laminate of two opposing battery cell laminates mesh and are coupled to each other, so that adjacent cell blocks are coupled to each other. By coupling the combined first side support plate and second side support plate to the cell block mounting area, the cell blocks can be fixedly installed in the pack housing.

[0027] The combined first side support plate and second side support plate form a laminate partition member that partitions each battery cell laminate, and the cover plate assembly may be coupled to the upper surface of the laminate partition member.

Advantages of the Invention

[0028] The present invention includes a cover plate assembly that covers the top and front surfaces of a battery module. Therefore, even if a flame occurs in one battery module, it is possible to protect adjacent battery modules from the flame and further prevent the flame from spreading to adjacent battery modules.

[0029] Furthermore, since the cover plate assembly has an insulating function, it can electrically insulate the terminal portion located on the front of the battery module.

[0030] The present invention is applicable not only to conventional battery modules but also to battery packs that house cell blocks in a moduleless structure, where all or part of the module case is absent. By installing such cell blocks within the pack, a so-called cell-to-pack structure battery pack can be achieved. Therefore, the present invention is also effective in preventing heat transfer in a cell-to-pack structure battery pack.

[0031] Furthermore, in one embodiment of the present invention, the cover plate assembly includes a rear cover plate, so that the rear surface of the battery unit can be protected from flames.

[0032] Furthermore, in one embodiment of the present invention, since the cell blocks have a structure that connects to one another, and a cover plate assembly can be attached to these connected cell blocks, there is no need to separately install partition members in the pack housing. Therefore, a battery pack with a simpler cell-to-pack structure can be manufactured, and the energy density can be further improved. [Brief explanation of the drawing]

[0033] [Figure 1] This is a schematic diagram showing an example of a conventional battery pack. [Figure 2] This is a perspective view showing a battery pack of one embodiment of the present invention. [Figure 3] This is a schematic diagram showing the structure of a typical battery module. [Figure 4]This is a perspective view showing the connection between the battery module and the cover plate assembly. [Figure 5] This is a perspective view showing the connection between the battery module and the cover plate assembly. [Figure 6] This is a schematic diagram showing the process by which the cover plate assembly is attached to the battery pack. [Figure 7] A perspective view showing the cover plate assembly attached to the battery pack. [Figure 8] This is a side cross-sectional view showing the cover plate assembly connected to the battery pack. [Figure 9] This is a perspective view showing the coupling relationship between a cover plate assembly and a battery module, which is applicable to other embodiments of the present invention. [Figure 10] This is a side cross-sectional view showing a battery pack of another embodiment of the present invention. [Figure 11] This is a perspective view showing an example of a moduleless cell block as a battery unit. [Figure 12] This is a perspective view showing an example of a moduleless cell block as a battery unit. [Figure 13] This is a perspective view showing a battery pack of another embodiment of the present invention. [Figure 14] This perspective view shows another example of a moduleless cell block as a battery unit. [Figure 15] Figure 14 is a schematic diagram showing the coupling process of a modularless cell block. [Figure 16] Figure 14 is a perspective view showing the coupling process of the battery pack according to the embodiment. [Figure 17] Figure 14 is a perspective view showing the coupling process of the battery pack according to the embodiment. [Modes for carrying out the invention]

[0034] The present invention will become more apparent by describing preferred embodiments in detail with reference to the accompanying drawings. The embodiments described herein are illustrative for the purpose of aiding the understanding of the invention, and the present invention may be carried out in various modified ways different from the embodiments described herein. Furthermore, the accompanying drawings provided for the purpose of aiding the understanding of the invention are not drawn to actual scale, and the dimensions of some components may be exaggerated.

[0035] The present invention will be described in detail below.

[0036] The battery pack 1000 of the present invention includes a plurality of battery units 100, each containing a battery cell stack 50 and each having a terminal portion T on the front surface of the battery unit 100 that is electrically connected to the battery cell stack 50; a battery unit mounting area and a pack housing having partition members 223 that divide the battery unit mounting area into a plurality of sections, with each of the battery units 100 housed in the battery unit mounting area between the partition members 223; and a cover plate assembly that covers the top and front surfaces of the battery units 100 and is coupled to the partition members 223.

[0037] The cover plate assembly 300 of the present invention can be applied not only to conventional battery modules but also to cell blocks with a moduleless structure in which all or part of the module case has been removed. Accordingly, in this specification, the term "battery unit" is proposed as a concept that includes both such battery modules and cell blocks. The battery unit 100 of the present invention basically includes a battery cell stack 50 and includes terminals T (terminal busbars) so that the battery cell stack 50 can output an electrical output. The battery cell stack 50 is formed by stacking a plurality of battery cells 51.

[0038] The terminal portion T described above is electrically connected to the electrode leads 51a, 51b of the battery cell stack 50, and is also electrically connected to the terminal portion T of an adjacent battery unit 100 or an external electrical device. Such terminal portions T may be provided on busbar assemblies 121, 131 or busbar frames, end plates 112, or combinations of busbar assemblies / frames and end plates that are coupled to the front or rear end of the battery cell stack 50. For example, if the battery unit 100 is a battery module 110, the battery module 110 may comprise a module case 111 that houses the battery cell stack 50, and busbar frames that are coupled to the battery cell stack 50 at the front and rear ends of the module case 111. If necessary, the busbar frame may be coupled to an end plate 112 or may be integrally formed with the end plate 112. The busbar frame comprises interbusbars, connectors, and terminal busbars (terminals) T that are electrically connected to the electrode leads of the battery cells 51.

[0039] A typical battery module 110 includes a module case 111 that completely encloses the edges of the battery cell stack 50. However, in recent years, in order to simplify the structure, reduce the number of components, and increase energy density, moduleless modules or cell blocks have been proposed in which all or part of the module case 111 is removed. A battery pack 1000 composed of such moduleless cell blocks 120, 120', and 130 is called a cell-to-pack battery pack 3000 or 4000. The cell blocks 120, 120', and 130 also include a battery cell stack 50. Furthermore, because all or part of the module case 111 is absent, at least part of the top, bottom, left, and right sides of the battery cell stack 50 is open to the outside. The moduleless cell blocks 120, 120', and 130 also include terminals T that are connected to the electrode leads of the battery cell stack 50 for electrical connection. For this purpose, busbar assemblies 121 and 131 can be attached to the front and rear ends of the battery cell stack 50.

[0040] Depending on the electrical connection configuration, the terminal section T may be provided on the front, or on both the front and rear, of the battery unit 100 described above.

[0041] The pack housing 200 has a battery unit mounting area for accommodating multiple battery units 100.

[0042] The battery unit mounting area described above becomes the bottom plate of the pack housing 200, i.e., the base plate 221. The base plate 221 may have a coolant flow path, or a separate heat sink may be installed below the base plate 221. The pack housing 200 also includes a side wall frame 222 surrounding the base plate 221, and the combination of the base plate 221 and the side wall frame 222 may be referred to as the lower pack housing 220. The pack housing 200 is constructed by connecting the upper cover (upper pack housing 210) to the lower pack housing 220.

[0043] Multiple battery units 100 are housed within the pack housing 200. Typically, partition members 223 are provided to align the battery units 100 within the pack housing 200. That is, the partition members 223 divide the battery unit mounting area into multiple sections, and each battery unit 100 is housed in one of the battery unit mounting areas between the partition members 223. The partition members 223 are fixedly installed in the battery unit mounting area, i.e., on the base plate 221.

[0044] As will be described later, the present invention can be applied not only when a partition member 223 is pre-installed in the pack housing 200, but also when it is not pre-installed. That is, in one embodiment of the present invention, side support plates provided on both sides of the cell block are coupled to each other to form a laminate partition member 132 that divides the battery cell laminate 50 provided in the cell block. In this case, the cell block and the laminate partition member 132 can be fixed to the pack housing 200 at the same time by coupling the laminate partition member 132 to the base plate 221 of the pack housing 200. In this embodiment, a cover plate assembly 300 can be coupled to the laminate partition member 132.

[0045] In addition to the partition members 223, a center frame 224 may be installed in the pack housing 200. The center frame 224 extends across the battery unit mounting area. Multiple partition members 223 may be arranged on both sides of the center frame 224 perpendicular to the direction of extension of the center frame 224. By positioning the center frame 224, the battery units 100 on the left and right sides of the center frame 224 can be separated and electrically isolated. The center frame 224 and the battery units 100 are separated by a predetermined insulating distance. As will be described later, the front cover plate 320 of the cover plate assembly 300 may be inserted and installed in the space between the front of the battery unit 100 and the center frame 224.

[0046] The present invention includes a cover plate assembly 300 that covers the top and front surfaces of a battery unit 100 and is coupled to a partition member 223 or a laminated partition member 132.

[0047] If any one of the battery units 100 catches fire, the flame will erupt in all directions. Since a base plate 221 with a cooling structure is installed below the battery unit 100, flame propagation downwards can be suppressed. Also, since partition members 223 (or stack partition members 132) are located on both sides of the battery unit (or battery cell stack 50), flame propagation to both sides of the battery unit can also be prevented. Furthermore, the rear surface of the battery unit 100 usually faces the side wall frame 222 of the pack housing 200. Recently proposed side wall frames 222 of pack housing 200 are often equipped with a venting mechanism to guide the gas and flame inside the pack to the outside. Since the rear surface of the battery unit 100 is located adjacent to such a venting mechanism, flame propagation to the rear of the battery unit 100 can also be suppressed to some extent.

[0048] However, since the top surface of the battery unit 100 is open, it is difficult to prevent flame propagation. The cover plate assembly 300 of the present invention covers the front surface of the battery unit 100 and is connected to the partition member, so it can prevent sparks and flames from being ejected from the top of the battery unit 100.

[0049] Since the front of the battery unit 100 is equipped with terminals T, it is very vulnerable when a flame is generated. The cover plate assembly 300 also covers the front of the battery unit 100. In other words, by simultaneously covering the top and front surfaces of the battery unit 100, which is most vulnerable to flames, the cover plate assembly 300 can prevent flames and sparks from spreading to adjacent battery units 100.

[0050] The cover plate assembly 300 may include a top cover plate 310 that covers the top surface of the battery unit 100, and a front cover plate 320 that is perpendicularly connected to one end of the top cover plate 310 and covers the front of the battery unit 100. Such a cover plate assembly 300 can cover the top and front of all battery units 100 housed in the pack housing 200. That is, one large cover plate assembly 300 can be configured to cover the top and front of multiple battery units 100. For example, if multiple battery units 100 are arranged on the left and right sides of a center frame 224, flame propagation can be suppressed by installing only one cover plate assembly 300 on each side.

[0051] In this case, there is the advantage that the number of cover plate assemblies 300 required to prevent flame propagation can be reduced. However, since the top and front of multiple battery units are covered by one large top cover plate 310 and front cover plate 320, the space between the battery units 100 is also partially closed. As the volume of the open space between the battery units 100 decreases in this way, the pressure inside the pack during gas venting increases, which can increase the risk of explosion. In addition, if one battery unit 100 malfunctions or ignition occurs and damages the cover plate assembly 300, the entire cover plate assembly 300 must be removed, which increases the cost of replacing parts.

[0052] Considering these points, it is preferable to install multiple cover plate assemblies 300 corresponding to the number of battery units 100. That is, each cover plate assembly 300 can cover each battery unit 100 and be connected to a partition member (or laminate partition member 132). This allows each cover plate assembly 300 to suppress flames generated on the front and rear surfaces of the battery unit 100, while also allowing gas to be discharged through the minute gaps between each cover plate assembly 300 to reduce the pressure inside the pack.

[0053] Even if the cover plate assembly 300 covers the rear surface of the battery unit 100, there is still a risk of increased pressure inside the pack. Therefore, the cover plate assembly 300 of the present invention covers only the top and front surfaces of the battery unit 100. However, if a suitable pressure relief means is provided, the cover plate assembly 300 can also cover the rear surface of the battery unit 100. One embodiment of the present invention shows an example in which the rear surface of the battery unit 100 is covered.

[0054] Specific embodiments of the present invention will be described below with reference to the drawings.

[0055] (First Embodiment) Figure 2 is a perspective view showing a battery pack 1000 according to one embodiment of the present invention, Figure 3 is a schematic diagram showing the structure of a typical battery module 110, and Figures 4 and 5 are perspective views showing the coupling relationship between the battery module 110 and the cover plate assembly 300.

[0056] This embodiment is an example in which a standard battery module 110 is used as the battery unit 100.

[0057] Referring to Figures 2 and 3, the battery module 110 includes a battery cell stack 50, a module case 111 housing the battery cell stack 50, and end plates 112 coupled to the front and rear surfaces of the module case 111. The module case may, but is not limited to, an upper case 111a and a lower case 111b. A busbar frame is coupled to the inside of the end plates 112, and terminal portions T extending from the busbar frame are exposed on both sides of the end plates 112. Referring to the coupled perspective view of the battery module 110 in Figure 3, it can be seen that the terminal portions T are exposed on the front surface of the battery module 110. The module case 111 may be provided with venting holes H to discharge gas from inside the module.

[0058] Figure 2 shows a pack housing 200 having a battery module mounting area and partition members that divide the battery module mounting area into multiple sections. The pack housing 200 consists of an upper pack housing 210 and a lower pack housing 220. The lower pack housing 220 includes a base plate 221 that forms the battery module mounting area and a side wall frame 222 arranged along the edge of the base plate 221. A center frame 224 is installed on the base plate 221 so as to cross the battery module mounting area. The side wall frame 222 may have a gas venting channel C inside, and the gas venting channel C may communicate with a venting opening 221a that is open to the outside.

[0059] Referring to Figure 2, the extension direction of the center frame 224 (the width direction of the battery module 110) is shown in the X direction. The battery modules 110 are arranged perpendicular to the X direction, and this direction is the longitudinal direction of the battery module 110. The Z direction is the height direction.

[0060] Furthermore, partition members 223 are installed on the base plate 221 to demarcate the battery module mounting area. Multiple partition members 223 are arranged perpendicular to the extension direction of the center frame 224 on both sides of the center frame 224. The battery modules 110 are positioned between the partition members 223 such that the front surfaces of the battery modules 110 face toward the center frame 224. The upper surface 223a of the partition members 223 is provided with fastening holes 223b so that they can be fastened to the upper cover plate 310 of the cover plate assembly.

[0061] The cover plate assembly 300 is connected to the partition member 223 while covering the top and front surfaces of the battery module 110. As shown in Figure 2, in this embodiment, multiple cover plate assemblies 300 are provided to correspond to the number of battery modules 110, and each cover plate assembly 300 covers each battery unit 100 and is connected to the partition member 223.

[0062] Figures 4 and 5 are intended to show the connection between the battery module 110 and the cover plate assembly 300, and are enlarged views of only the battery module 110, the partition member 223 between the battery modules 110, and the cover plate assembly 300 shown in Figure 2.

[0063] In Figures 4 and 5, the partition member 223 is pre-attached to the pack housing. The battery module 110 is positioned between the partition members 223 and is fixed to the partition members 223 or the base plate 221 of the pack housing 200 by fastening members (not shown).

[0064] In this state, each cover plate assembly 300 is positioned to cover the top and front surfaces of each battery module 110, and then the cover plate assembly 300 is connected to the partition wall member 223.

[0065] Specifically, the cover plate assembly 300 includes an upper cover plate 310 that covers the upper surface of the battery module 110, and a front cover plate 320 that is perpendicularly connected to one end of the upper cover plate 310 and covers the front surface of the battery module 110.

[0066] The top cover plate 310 and the front cover plate 320 described above can be made of the same material or different materials. Since the front cover plate 320 covers the front of the battery where the terminal portion T is installed, it is preferable that it be made of an electrically insulating material. For example, the front cover plate 320 can be made from an electrically insulating ceramic material such as mica. The top cover plate 310 can also be made from an insulating material such as mica. However, the top cover plate 310 can be made from a metal material that is highly rigid and has a high melting point so that it can resist flames rising from above. For example, the top cover plate 310 can be made from stainless steel, aluminum or aluminum alloy, or steel.

[0067] Preferably, the front cover plate 320 may be made of an insulating material (e.g., mica), and the top cover plate 310 may be made of a high-melting-point metal material (e.g., steel). When the top cover plate 310 and the front cover plate 320 are made of the same material, one end of the top cover plate 310 may be bent vertically, and this bent portion may become the front cover plate 320. Alternatively, a cover plate assembly 300 can be made by joining a front cover plate 320 made of a different material to the top cover plate 310. For example, a front cover plate 320 made of mica may be joined to the end of a top cover plate 310 made of steel. The top cover plate 310 and the front cover plate 320 can be fastened together with fasteners such as screws or bolts. Alternatively, the top cover plate 310 and the front cover plate 320 can be joined together by bonding with a predetermined adhesive or by other methods such as welding.

[0068] Referring to Figures 4 and 5, it is shown that one end of the top cover plate 310 is bent vertically to form a joint portion 312 of a predetermined length, and the front cover plate 320 is bonded or fastened to the inner surface of this joint portion 312 to connect the front cover plate 320 to the top cover plate 310. For example, the end of the top cover plate 310 made of steel can be bent to form the joint portion 312, and the front cover plate 320 made of mica material can be bonded to the inner surface of the bent portion to produce the cover plate assembly 300. In addition to the mica mentioned above, the front cover plate can be made from other materials that have insulating properties. Furthermore, in addition to the metal materials mentioned above, the top cover plate can be made from other materials that have fire-resistant and fire-proof properties.

[0069] The top cover plate 310 is formed to be long enough to cover the entire top surface of the battery module 110. That is, the length L1 of the top cover plate 310 must be the same as, or longer than, the combined length L2 of the module case 111 and the thickness of the end plate 112. However, if the top cover plate 310 is too long, the distance between the front cover plate 320 located at the end of the top cover plate 310 and the end plate 112 will increase, and there is a risk of contact with the center frame 224 at the front of the battery module. Therefore, the length L1 of the top cover plate 310 should be the same as, or slightly longer than, the combined length L2 of the module case 111 and the thickness of the end plate. The width W1 of the top cover plate 310 should be the same as, or slightly larger than, the width W2 of the battery module 110 so that it can completely cover the width W2 of the battery module 110.

[0070] The length (height) of the front cover plate 320 should preferably be the same as the height of the battery module 110 so that it can cover the front of the battery module 110. However, considering the space inside the pack and the space for other components, the height of the front cover plate 320 may be slightly smaller than the height of the battery module 110. The shapes of the front cover plate 320 in Figures 4 and 5 are slightly different. The front cover plate 320 in Figure 4 is rectangular in shape and covers the front of the battery module 110. The front cover plate 320 in Figure 5 is provided with cutouts 321 at both corners of the lower end. The pack housing 200 may have coupling protrusions (not shown) for coupling to the bottom corners of the battery module 110. The cutouts 321 are to avoid the coupling protrusions if they are installed. In other words, when the corner of the battery module 110 is connected to the connecting protrusion of the pack housing 200, the connecting protrusion will be located in the space of the cut portion 321, and the front cover plate 320 can be installed so as to fit snugly to match the shape of the battery module 110 and the connecting protrusion. The front cover plate 320 will either be in close contact with the end plate 112 on the front of the module, or at a predetermined distance from the end plate, to protect the terminal portion T and other electrical components installed on the end plate.

[0071] The cover plate assembly 300 is connected to the partition member 223 by connecting the top cover plate 310 to the upper surface 223a of the partition member 223. For this purpose, the top cover plate 310 may have a plurality of fastening portions 311 along both sides of the cover plate. The fastening portions may be provided with fastening holes 311a. Multiple fastening portions 311 may be provided at intervals along both sides of the top cover plate 310. As shown in Figures 4 and 5, the fastening portions 311 of adjacent top cover plates 310 may be configured to interlock with each other. That is, if the fastening portions 311 of the side of the top cover plate 310 of adjacent cover plate assemblies 300 are positioned to interlock with the spacing between the fastening portions 311 of the side of the top cover plate 310 of one cover plate assembly 300, the fastening portions of adjacent top cover plates 310 will be placed on the same partition member 223. Therefore, by fastening (connecting) the fastening portions 311 of adjacent upper cover plates 310 to the upper surface of the partition member 223, the space required for connection can be reduced. In addition, by interlocking and connecting the upper cover plates 310 of adjacent cover plate assemblies 300, the space occupied by the cover plate assemblies 300 within the pack can be reduced, and at the same time, the cover plate assemblies 300 can be more firmly connected to the partition member 223. However, as shown in Figure 2, the fastening portion 311 of the upper cover plate 310 of the cover plate assembly 300 that is connected to the partition member 223 located on the outermost side in the X direction does not interlock with the fastening portion 311 of the adjacent upper cover plate 310 because there is no adjacent upper cover plate 310.

[0072] Figure 6 is a schematic diagram showing the process of the cover plate assembly 300 being coupled to the battery pack 1000, while Figures 7 and 8 are perspective and side cross-sectional views, respectively, showing the cover plate assembly 300 coupled to the battery pack 1000.

[0073] Referring to Figure 6, the battery modules 110 are arranged side by side with a partition member 223 in between. Terminal portions T are located at the upper ends on both sides of the end plates 112 installed on the front of the battery modules 110. The terminal portions T of adjacent battery modules 110 separated by the partition member 223 are electrically connected to each other by an interbus bar B. To ensure space for the interbus bar B to connect, the front edge of the partition member 223 located between the battery modules 110 is cut open. The interbus bar connects the terminal portions T of the battery modules 110 on both sides through this cut open edge (see Figures 6(a) and 6(b)).

[0074] After the interbus bar B is connected, the cover plate assembly 300 is secured from the top of the battery module 110, and the fastening portion 311 of the cover plate assembly 300 is fastened to the upper surface 223a of the partition wall member 223 between the battery modules 110 (see Figure 6(c)).

[0075] Figure 7 shows that multiple cover plate assemblies 300 are each connected to the partition members 223 between the battery modules 110 and then fixed onto the multiple battery modules 110. Subsequently, the battery pack assembly process of the present invention is completed by fastening the upper cover 210 to the lower pack housing 220 so that the upper cover 210 covers the cover plate assemblies 300.

[0076] Figure 8 clearly shows the coupling relationship of the cover plate assembly 300 of the present invention. As shown in the figure, the upper cover plate 310 of the cover plate assembly 300 covers the upper surface of the battery module 110, suppressing flame propagation to the top of the module. The front cover plate 320 covers the front of the module. Figure 8 assumes that the battery cell 51 in the module is a bidirectional pouch cell with electrode leads 51a and 51b led out on both sides of the cell. However, the present invention can also be applied to a battery module composed of a unidirectional pouch cell with electrode leads led out on one side of the cell. Electrode leads 51a and 51b are led out from the front and rear of the battery cell, and these electrode leads are electrically connected to an interbus bar or terminal bus bar T. Since the front cover plate 320 is positioned to cover the terminal bus bar (terminal section T) on the front of the battery module 110, the terminal section T is protected from flames. As shown in the figure, a gas venting channel C of the side wall frame 222 is located on the rear surface of the battery module 110, so that flames generated on the rear surface of the battery module 110 can be discharged relatively quickly through the gas venting channel. The gas venting channel communicates with a gas outlet 222a formed on the outer surface of the pack housing 200.

[0077] (Second Embodiment) Figure 9 is a perspective view showing the coupling relationship between a cover plate assembly 300' and a battery module 110 applied to another embodiment of the present invention, and Figure 10 is a side cross-sectional view showing a battery pack 2000 of another embodiment of the present invention.

[0078] The configuration of the battery module 110 and pack housing 200 applied to this embodiment is the same as that of the first embodiment. Furthermore, the cover plate assembly 300' also includes the top cover plate 310 and the front cover plate 320, which is also the same. A description of the same configuration as in the first embodiment will be omitted.

[0079] This embodiment differs from the first embodiment in that the cover plate assembly 300' has a rear cover plate 330. As shown in Figure 9, the cover plate assembly 300' of this embodiment has a front cover plate 320 at one end of the top cover plate 310, and further includes a rear cover plate 330 which is perpendicularly connected to the other end of the top cover plate 310 and covers the rear surface of the battery module 110. As described above, covering the rear surface in addition to the top and front surfaces of the battery module 110 poses a risk of increased pressure inside the pack during heat transfer.

[0080] In this embodiment, a plurality of venting holes 331 are formed in the rear cover plate 330 to prevent an increase in pressure inside the pack during heat transfer.

[0081] The rear cover plate 330 and the top cover plate 310 may be made of the same or different materials. For example, the top cover plate 310 may be made of steel, and the rear cover plate 330 may be made of mica material with insulating properties. The rear cover plate 330 may be made of the same material and have the same form as the front cover plate 320.

[0082] The method of joining the rear cover plate 330 and the top cover plate 310 can also be the same as the method of joining the top cover plate 310 and the front cover plate 320. Figure 9 shows that the other end of the top cover plate 310 is bent vertically, and the rear cover plate 330 is joined to this bent end.

[0083] Since multiple venting holes 331 are formed in the rear cover plate 330, if gas is generated inside the pack during heat transfer and the gas pressure increases, the gas can be discharged through these venting holes 331, thereby preventing an increase in pressure. In particular, by making the venting holes 331 of the rear cover plate 330 communicate with the outside, gas discharge can be facilitated.

[0084] As shown in Figure 10, when a gas venting channel C is formed in the side wall frame 222 of the pack housing 200, the rear cover plate 330 can be installed such that the venting holes 331 of the rear cover plate 330 face or come into contact with the inlet 222c of the gas venting channel. In the example of Figure 10, if a flame is generated due to thermal runaway of a particular battery module 110, the top cover plate 310 and the front cover plate 320 of the cover plate assembly 300 prevent the flame from spreading to adjacent battery modules 110. Furthermore, the rear cover plate 330 of the cover plate assembly 300 can prevent the flame from spreading behind the battery module 110. In this case, if gas is generated from the battery module 110, the gas can be discharged to the outside through the venting holes 331 of the rear cover plate 330 and the gas venting channel C of the side wall frame 222 that communicates with it.

[0085] Therefore, this embodiment has the advantage of being able to prevent pressure rise inside the pack while maximizing the effect of preventing flame propagation inside the pack.

[0086] (Third embodiment) Figures 11 and 12 are perspective views showing an example of a moduleless cell block as a battery unit 100, and Figure 13 is a perspective view showing a battery pack 3000 of another embodiment of the present invention.

[0087] As described above, in addition to the battery module 110, a moduleless cell block 120, 120' can be used as the battery unit 100.

[0088] Figure 11 discloses a battery cell stack 50 and a cell block 120 in which busbar assemblies 121 are connected to the front and rear surfaces of the stack. This cell block 120 has a moduleless structure in which the module cases 111 that cover the top, bottom, left, and right sides of the battery cell stack 50 are completely absent.

[0089] Figure 12 discloses a cell block 120' comprising a battery cell stack 50, busbar assemblies 121 connected to the front and rear surfaces of the stack, and side support plates 123 connected to both sides of the battery cell stack 50. The cell block 120' in Figure 12 has an open top and bottom surface of the battery cell stack 50 and is a moduleless structure lacking a portion of the module case 111.

[0090] The battery cells 51 described above are stacked so that their sides are in contact with each other, and the sides of adjacent battery cells can be fixed together via double-sided tape. Alternatively, multiple stacked battery cells can be bundled together with a band 122 to form a single battery cell stack 50 (see Figures 11 and 12).

[0091] A busbar assembly 121 is connected to the electrode leads on the front and rear surfaces of the battery cell stack 50. The busbar assembly is provided with terminals T.

[0092] Figure 13 shows that such a modular cell block 120' is installed in the pack housing 200. Similar to the first embodiment, the pack housing 200 includes a battery unit (cell block) mounting area and partition wall members 223 that demarcate this cell block mounting area. Also, similar to Figure 2, a center frame 224 and a plurality of partition wall members 223 are arranged perpendicularly to the center frame 224.

[0093] The cell blocks are arranged between the partition members 223 such that the front surface of the cell block 120', on which the terminal portion T is installed, faces toward the center frame 224.

[0094] The cell block 120' can be installed between the partition members 223 after compressing the side support plates 123 installed on both sides of the battery cell stack, or on both sides of the stack, to reduce their volume. In this case, the side support plates 123 can be fastened to the partition members 223 with fastening members or the like.

[0095] In this embodiment as well, the cover plate assembly 300, which includes the top cover plate 310 and the front cover plate 320, is fixed onto the cell block 120' from the top of each cell block. The top cover plate 310 is connected to the upper surface of the partition wall member 223 that divides the cell block, protecting the top and front surfaces of the cell block 120 from flames.

[0096] Since the battery pack 3000 of this embodiment relates to a moduleless cell block structure that lacks all or part of the module case 111, the cover plate assembly 300 performs a greater function. That is, the top cover plate 310 not only prevents flames but also covers the top of the cell block that lacks the module case 111, and can protect the top of the battery cell stack 50. In other words, the moduleless cell blocks 120, 120' can reduce the number of related parts and increase energy density because the module case is removed, but they are vulnerable in the event of contamination or flames occurring inside the pack because part of the cell block is exposed. The cover plate assembly 300 can cover such a moduleless cell block and effectively protect the cell block from contaminants and flames inside the pack.

[0097] (Fourth Embodiment) Figure 14 is a perspective view showing another example of a moduleless cell block as a battery unit, Figure 15 is a schematic diagram showing the coupling process of the moduleless cell block in Figure 14, and Figures 16 and 17 are perspective views showing the coupling process of the battery pack 4000 of the embodiment in Figure 14.

[0098] Similar to the third embodiment, this embodiment uses a battery unit 100 consisting of a cell block 130 with a moduleless structure that lacks a portion of the module case housing the battery cell stack 50. However, this embodiment differs from the first to third embodiments in that the cover plate assembly 300 is not connected to the partition wall member 223 of the pack housing 200, but rather to the cell block 130 itself.

[0099] Referring to Figure 14, the cell block 130 of this embodiment includes a battery cell stack 50, a busbar assembly 131 connected to the front of the battery cell stack 50, and a first side support plate 132A and a second side support plate 132B connected to both sides of the battery cell stack 50.

[0100] The busbar assembly 131 described above is equipped with terminal busbars T on the upper sides.

[0101] The cell block 130 of the present invention is fixedly installed in the cell block mounting area of ​​the pack housing 200. Specifically, the cell block can be fixed to the pack housing 200 by connecting the first side support plate 132A and the second side support plate 132B, which are coupled to both sides of the cell block 130, to the base plate 221 of the pack housing 200.

[0102] In particular, the cell block 130 of this embodiment is equipped with a first side support plate 132A and a second side support plate 132B that have a unique structure that allows adjacent cell blocks to be connected to each other.

[0103] Referring to Figure 14, the first side support plate 132A and the second side support plate 132B consist of the first side support plate 132A, which is coupled to one side of the battery cell stack 50, and the second side support plate 132B, which is coupled to the other side.

[0104] The first side support plate 132A and the second side support plate 132B described above have complementary structures that interlock with each other. For example, as shown in Figure 14, the first side support plate 132A has a stepped structure with a protrusion A on the upper side and a recess B on the lower side. On the other hand, the second side support plate 132B has a stepped structure with a protrusion A' on the lower side and a recess B' on the upper side. The stepped structure of the first side support plate 132A and the stepped structure of the second side support plate 132B are designed to interlock and fit together. Therefore, by interlocking the first side support plate 132A of one cell block 130 with the second side support plate 132B of the adjacent cell block 130 facing it, and connecting the first side support plate 132A and the second side support plate 132B with a fastening member, adjacent cell blocks can be connected to each other. Each side support plate is provided with fastening holes 133a at the same position so that the first side support plate 132A and the second side support plate 132B can be joined together. That is, as shown in Figure 14, multiple fastening holes 133a are formed through the upper surface 133 of the protrusion of the first side support plate 132A, and multiple fastening holes 133a' are formed through the protrusion A' on the lower side of the second side support plate 132B at positions corresponding to the fastening holes mentioned above. Therefore, the first side support plate and the second side support plate can be joined together by fastening members such as bolts passing through the fastening holes of the first side support plate 132A and the second side support plate 132B.

[0105] Figure 15 shows that the first side support plate 132A and the second side support plate 132B of adjacent cell blocks are joined to each other through this joining process. As shown in Figure 15, the joined body of the first side support plate and the second side support plate becomes a stacked partition wall member 132 that divides adjacent battery cell stacks 50. In this embodiment, the cover plate assembly 300 can be joined to the upper surface of the stacked partition wall member 132. That is, the fastening portion 311 of the upper cover plate 310 of the cover plate assembly 300 can be fastened to the upper surface 133 of the stacked partition wall member 132. The stacked partition wall member 132 differs from other embodiments in that it is not a partition wall member 223 pre-installed in the pack housing 200, but is formed only after the joining of the cell blocks.

[0106] Figure 16 shows a pack housing 200 including a center frame 224 that extends across the cell block mounting area. Unlike the pack housing 200 in Figure 2, this pack housing 200 does not have a partition member 223 installed in the cell block mounting area. As shown in Figure 15, adjacent cell blocks 130 can form two rows of cell block assemblies on both sides of the center frame 224, as shown in Figure 16, by complementaryly connecting their opposing side support plates. The cell block assemblies are installed on both sides of the center frame 224 so that multiple cell blocks are arranged perpendicular to the center frame 224 and the front surfaces of the cell blocks 130 face the center frame 224.

[0107] The cell block or cell block assembly described above can be fixed to the pack housing 200 by connecting the laminated partition wall member 132 to the base plate 221 of the pack housing 200. For example, when connecting the fastening members 133a and 133b through the fastening holes of the first side support plate 132A and the second side support plate 132B shown in Figure 14, the ends of the fastening members can be connected to the base plate 221, thereby enabling simultaneous connection of the cell block and connection of the cell block to the base plate 221. Alternatively, separate fastening holes can be formed on the upper surface of the laminated partition wall member 132 (the upper surface of the first side support plate), which is composed of the first side support plate 132A and the second side support plate 132B, and the fastening members can be inserted into these fastening holes and fastened to the base plate 221.

[0108] As shown in Figure 17, once the cell block is coupled to the pack housing 200, the cover plate assembly 300 can be coupled to the cell block. That is, the top cover plate 310 of the cover plate assembly 300 can be fastened onto the laminate partition member 132 formed by coupling the first side support plate 132A and the second side support plate 132B between adjacent battery cell laminates 50. If necessary, the fastening holes of the first and second side support plates and the fastening holes of the fastening portion of the top cover plate 310 can be formed in the same position. In this case, the fastening holes of the first and second side support plates and the fastening holes of the top cover plate 310 can be aligned, and the same fastening member can be inserted into the aligned fastening holes for fastening. This makes it possible to achieve the coupling of the cell block and the coupling of the cover plate assembly 300 simultaneously.

[0109] According to this embodiment, not only is the structure of the battery pack 1000 simplified by using a moduleless cell block, but the laminated partition member 132 can be formed by joining the cell blocks without a separate partition member 223, thus further simplifying the structure of the battery pack 1000. Therefore, the energy density can be further improved.

[0110] On the other hand, the second embodiment described a case in which a battery module 110 was used as the battery unit 100. However, the cover plate assembly 300 of the second embodiment can also be applied when using moduleless cell blocks 120, 120', and 130 as in the third and fourth embodiments. That is, in the battery pack 1000 of the third and fourth embodiments, flame propagation on the rear surface of the cell block can be prevented by fastening the cover plate assembly 300, which is equipped with a rear cover plate 330, to the partition member 223 or the laminated partition member 132.

[0111] The above description is merely illustrative of the technical concept of the present invention, and a person with ordinary skill in the art to which the present invention belongs can make various modifications and variations without departing from the essential characteristics of the present invention. Therefore, the drawings disclosed herein are for illustrative purposes only, not to limit the technical concept of the present invention, and the scope of the technical concept of the present invention is not limited by such drawings. The scope of protection of the present invention should be interpreted by the claims, and all technical concepts within an equivalent scope should be interpreted as being included in the scope of rights of the present invention. [Explanation of Symbols]

[0112] 50: Battery cell stack 51: Battery cell 100: Battery Unit 110: Battery module 111: Module Case 112: End plate T: Terminal section 120, 120', 130: Cell block 121: Busbar assembly 122: Band 123: Side support plate 131: Busbar assembly 132: Laminated partition member 132A: 1st side support plate 132B:Second side support plate 200: Pack Housing 210: Upper pack housing (upper cover) 220: Lower pack housing 221: Base plate 222: Side wall frame 223: Partition wall member 224: Center frame 300, 300': Cover plate assembly 310: Top cover plate 311: Fastening section 311a: Fastening hole 312: Joint part (bending part) 320: Front cover panel 321: Incision site 330: Rear cover plate 331: Venting Hall 1000, 2000, 3000, 4000: Battery Pack

Claims

1. A plurality of battery units, each containing a stack of battery cells, and each battery unit having a terminal portion on its front surface that is electrically connected to the stack of battery cells, A pack housing having a battery unit mounting area and partition wall members that divide the battery unit mounting area into multiple sections, with each battery unit housed in the battery unit mounting area between the partition wall members, A battery pack including a cover plate assembly that covers the top and front surfaces of the battery unit and is coupled to the partition member, The cover plate assembly includes an upper cover plate that covers the upper surface of the battery unit, and a front cover plate that is perpendicularly connected to one end of the upper cover plate and covers the front surface of the battery unit. Multiple fastening parts protrude at intervals along both sides of the upper cover plate, and the fastening parts are connected to the upper surface of the partition member. A battery pack in which the fastening parts on the sides of the upper cover plates of adjacent cover plate assemblies are positioned so that they interlock with the fastening parts on the sides of the upper cover plates of one cover plate assembly, thereby connecting the fastening parts of the upper cover plates of adjacent cover plate assemblies to the same partition member.

2. The aforementioned battery unit is The battery pack according to claim 1, comprising a battery module including a module case for housing the battery cell stack and end plates connected to the front and rear surfaces of the module case.

3. The aforementioned battery unit is A cell block having a moduleless structure in which busbar assemblies are connected to the front and rear surfaces of the battery cell stack, and all or part of the module case housing the battery cell stack is absent. The battery pack according to claim 1, wherein a terminal portion is provided on a busbar assembly that is coupled to the front surface of the battery cell stack.

4. The aforementioned modular cell block is Side support plates are attached to both sides of the aforementioned battery cell stack. The battery pack according to claim 3, wherein both the upper and lower surfaces of the battery cell stack are open, except for the surface to which the side support plate and the busbar assembly are joined.

5. The pack housing includes a center frame that extends across the battery unit mounting area, Multiple partition members are arranged on both sides of the center frame, perpendicular to the extension direction of the center frame. The battery pack according to claim 1, wherein the battery units are arranged between the partition members such that the front surfaces of the battery units face toward the center frame.

6. Multiple cover plate assemblies are provided, corresponding to the number of battery units. The battery pack according to claim 1, wherein each cover plate assembly covers each battery unit and is connected to a partition member.

7. The battery pack according to claim 1, wherein the front cover plate is formed from an electrical insulating material.

8. The cover plate assembly further includes a rear cover plate which is perpendicularly connected to the other end of the upper cover plate and covers the rear surface of the battery unit, The battery pack according to claim 1, wherein a plurality of venting holes are formed in the rear cover plate.

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