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 that houses battery units such as battery modules.

[0002] More particularly, the present invention relates to a battery pack capable of preventing the spread of sparks or flames to adjacent battery units in the event of a fire occurring within a battery unit.

[0003] This application claims the benefit of priority based on Korean Patent Application No. 10-2022-0120400 dated September 23, 2022, and all contents disclosed in the documents of said Korean patent application are incorporated herein by reference. [Background technology]

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

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

[0006] In Fig. 1, for convenience of illustration, the top cover of the battery pack 1 is omitted. As shown, 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 sides of a central center frame. A terminal unit 12 such as a terminal bus bar is provided on the front of the battery module 10, and the terminal units 12 of each battery module are electrically connected in series or in parallel to each other.

[0007] If a thermal runway occurs in a battery cell housed in any one battery module, the heat will be transferred to the adjacent battery cells, resulting in sparks and flames erupting on all sides of the battery module. In this case, the battery modules adjacent to the battery module from which the flame erupted will also be exposed to flames, which may lead to subsequent explosions of the battery modules.

[0008] Since a base plate of the pack housing equipped with a heat sink or cooling flow path is located below the battery module, flame propagation can be suppressed relatively easily.

[0009] However, as shown in FIG. 1, a space is formed between the top of the battery module and an upper cover (not shown), and thus a flame may erupt from this upper space. In particular, the front surface of the battery module where the terminals are installed is prone to overheating and ignition. In addition, the front surface of the module is vulnerable to ignition, as it is electrically short-circuited when a flame occurs. In addition, since the terminals are installed on the front surface of the battery module, electrical insulation is also required.

[0010] Therefore, there is a need to develop a technology that can simultaneously protect the top and front of a battery unit such as a battery module from flames and sparks. [Prior art documents] [Patent documents]

[0011] [Patent Document 1] Korean Patent Publication No. 10-2021-0134165 Summary of the Invention [Problem to be solved by the invention]

[0012] The present invention has been made to solve the above problems, and aims to provide a battery pack that can prevent sparks or flames from spreading to adjacent battery units by simultaneously covering the top and front of battery units such as battery modules. [Means for solving the problem]

[0013] In order to solve the above problems, a battery pack according to an embodiment of the present invention includes: a plurality of battery units, each including a battery cell stack, and each having a terminal portion electrically connected to the battery cell stack at 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, in which the battery units are accommodated in the battery unit mounting areas between the partition members; and a cover plate assembly covering upper and front surfaces of the battery units and coupled to the partition members.

[0014] The battery unit may be a battery module including a module case housing a battery cell stack and end plates coupled to front and rear surfaces of the module case.

[0015] The battery unit is a cell block having a moduleless structure in which a bus bar assembly is coupled to front and rear surfaces of a battery cell stack and all or a part of a module case accommodating the battery cell stack is eliminated, and a terminal portion may be provided on the bus bar assembly coupled to the front surface of the battery cell stack.

[0016] The cell block of the moduleless structure may have side support plates coupled to both side surfaces of the battery cell stack, and both upper and lower surfaces of the battery cell stack, except for surfaces where the side support plates and bus bar assemblies are coupled, may be open.

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

[0018] A plurality of the cover plate assemblies may be provided corresponding to the number of the battery units, and each cover plate assembly may cover a corresponding battery unit and be coupled to a partition member.

[0019] The cover plate assembly may include a top cover plate for covering a top surface of the battery unit, and a front cover plate for covering a front surface of the battery unit, the front cover plate being vertically coupled to one end of the top cover plate.

[0020] A plurality of fastening portions may protrude at intervals along both sides of the upper cover plate, and the fastening portions may be coupled to an upper surface of the partition member.

[0021] By positioning the fastening portions on the upper cover plate sides of adjacent cover plate assemblies so that they interlock with the gaps between the fastening portions on the upper cover plate sides of one cover plate assembly, the fastening portions of the upper cover plates of adjacent cover plate assemblies can each be joined onto the same partition member.

[0022] The front cover plate may be formed from an electrically insulating material.

[0023] The cover plate assembly further includes a rear cover plate vertically coupled to the other end of the top cover plate to cover a rear surface of the battery unit, and a plurality of vent holes may be formed in the rear cover plate.

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

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

[0026] The side support plate is composed of a first side support plate coupled to one side of the battery cell stack and a second side support plate coupled to the other side, the first side support plate and the second side support plate having complementary structures that mesh with each other, and the first side support plate of one battery cell stack of two opposing battery cell stacks and the second side support plate of the other battery cell stack are meshed and coupled to each other, thereby coupling adjacent cell blocks to each other, and the coupled first side support plate and second side support plate are coupled to the cell block mounting area, thereby allowing the cell blocks to be fixedly installed in the pack housing.

[0027] The coupled first and second side support plates form stack partition members that partition respective battery cell stacks, and the cover plate assembly can be coupled to an upper surface of the stack partition member. Effect of the Invention

[0028] The present invention includes a cover plate assembly that covers the upper and front surfaces of the battery modules, so that even if a fire occurs in one battery module, the adjacent battery modules can be protected from the fire and the fire can be prevented from spreading to the adjacent battery modules.

[0029] In addition, since the cover plate assembly has an insulating function, it can electrically insulate the terminals located on the front surface of the battery module.

[0030] The present invention is applicable not only to a normal battery module, but also to a battery pack containing a cell block of a moduleless structure in which all or part of a module case is missing. By installing such a cell block in the pack, a so-called cell-to-pack battery pack can be achieved. Therefore, the present invention is also effective in preventing heat propagation in a cell-to-pack battery pack.

[0031] In addition, in one embodiment of the present invention, since the cover plate assembly includes a rear cover plate, the rear surface of the battery unit can be protected from fire.

[0032] In addition, in one embodiment of the present invention, since the cell blocks are provided with a structure in which they are joined together and the cover plate assembly is joined onto the joined cell blocks, there is no need to install a separate partition member on the pack housing, so that a battery pack with a simpler cell-to-pack structure can be manufactured and the energy density can be further improved. [Brief description of the drawings]

[0033] [Figure 1] FIG. 1 is a schematic diagram showing an example of a conventional battery pack. [Diagram 2] 1 is a perspective view showing a battery pack according to an embodiment of the present invention; [Diagram 3] 1 is a schematic diagram showing the structure of a conventional battery module. [Figure 4]4 is a perspective view showing a coupling relationship between a battery module and a cover plate assembly; FIG. [Diagram 5] 4 is a perspective view showing a coupling relationship between a battery module and a cover plate assembly; FIG. [Figure 6] 11 is a schematic diagram showing a process in which a cover plate assembly is coupled to a battery pack; [Figure 7] FIG. 13 is a perspective view showing the cover plate assembly coupled to the battery pack; [Figure 8] FIG. 11 is a side cross-sectional view showing the cover plate assembly coupled to the battery pack. [Figure 9] 13 is a perspective view showing a coupling relationship between a cover plate assembly and a battery module applied to another embodiment of the present invention; FIG. [Figure 10] FIG. 4 is a side cross-sectional view showing a battery pack according to another embodiment of the present invention. [Figure 11] FIG. 2 is a perspective view showing an example of a module-less cell block as a battery unit; [Figure 12] FIG. 2 is a perspective view showing an example of a module-less cell block as a battery unit; [Figure 13] FIG. 11 is a perspective view showing a battery pack according to another embodiment of the present invention. [Figure 14] FIG. 11 is a perspective view showing another example of a module-less cell block as a battery unit. [Figure 15] 15 is a schematic diagram showing a coupling process of the module-less cell blocks of FIG. 14. [Figure 16] 15 is a perspective view showing a process of assembling the battery pack of the embodiment of FIG. 14. [Figure 17] 15 is a perspective view showing a process of assembling the battery pack of the embodiment of FIG. 14. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0034] The present invention will become clearer by describing in detail preferred embodiments of the present invention with reference to the attached drawings. The embodiments described herein are illustrative in order to aid in the understanding of the invention, and the present invention may be implemented in various forms different from the embodiments described herein. In addition, the attached drawings are not drawn to scale in order to aid in the understanding of the invention, 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 including a battery cell stack 50, and each having a terminal portion T electrically connected to the battery cell stack 50 on a front surface of the battery unit 100; a pack housing having a battery unit mounting area and partition members 223 dividing the battery unit mounting area into a plurality of areas, in which the battery units 100 are accommodated in the battery unit mounting areas between the partition members 223; and a cover plate assembly covering an upper surface and a front surface of the battery unit 100 and connected to the partition member 223.

[0037] The cover plate assembly 300 of the present invention can be applied not only to a conventional battery module but also to a cell block of a module-less structure in which all or a part of the module case is removed. Therefore, in this specification, the term "battery unit" is proposed as a concept including both the battery module and the cell block. The battery unit 100 of the present invention basically includes a battery cell stack 50, and includes a terminal part T (terminal bus bar) 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 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 the adjacent battery unit 100 or an external electric device. Such a terminal portion T may be provided in a busbar assembly 121, 131, or a busbar frame, an end plate 112, or a combination of a busbar assembly / frame and an end plate, which are coupled to the front or rear end of the battery cell stack 50. For example, when the battery unit 100 is a battery module 110, the battery module 110 may include a module case 111 in which the battery cell stack 50 is housed, and a busbar frame 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 the end plate 112 or may be integrally formed with the end plate 112. The busbar frame includes an inter-busbar, a connector, and a terminal busbar (terminal) T electrically connected to the electrode leads of the battery cells 51.

[0039] A typical battery module 110 includes a module case 111 that completely surrounds the edge of the battery cell stack 50. However, in recent years, in order to simplify the structure, reduce the number of parts, and increase the energy density, a module or cell block with a module-less structure in which all or a part of the module case 111 is removed has been proposed. A battery pack 1000 formed with such cell blocks 120, 120', 130 with a module-less structure is called a cell-to-pack battery pack 3000, 4000. The cell blocks 120, 120', 130 also include a battery cell stack 50. In addition, since all or a part of the module case 111 is absent, at least a part of the upper, lower, left, and right sides of the battery cell stack 50 are open to the outside. The cell blocks 120, 120', 130 with a module-less structure also include a terminal portion T that is connected to the electrode lead of the battery cell stack 50 for electrical connection. To this end, bus bar assemblies 121 , 131 may be coupled to the front and rear ends of the battery cell stack 50 .

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

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

[0042] The battery unit mounting area 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 under the base plate 221. In addition, the pack housing 200 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 a lower pack housing 220. An upper cover (upper pack housing 210) is combined with the lower pack housing 220 to form the pack housing 200.

[0043] A plurality of battery units 100 are accommodated in the pack housing 200. Typically, a partition member 223 is 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 a plurality of areas, and the battery units 100 are accommodated in 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., the base plate 221.

[0044] As described below, the present invention can be applied not only to the case where the partition member 223 is pre-installed in the pack housing 200, but also to the case where 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 may be coupled to each other to form a stack partition member 132 that partitions the battery cell stack 50 provided in the cell block. In this case, the stack partition member 132 may be coupled to a base plate 221 of the pack housing 200, so that the cell block and the stack partition member 132 may be fixed to the pack housing 200 at the same time. In this embodiment, a cover plate assembly 300 may be coupled to the stack 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 a battery unit mounting area. A plurality of partition members 223 may be arranged on both sides of the center frame 224 perpendicular to the extension direction of the center frame 224. As the center frame 224 is disposed, the battery units 100 on the left and right of the center frame 224 may be separated and electrically insulated. The center frame 224 and the battery units 100 are separated by a predetermined insulating distance. As described below, a front cover plate 320 of a cover plate assembly 300 may be inserted into a space between the front of the battery unit 100 and the center frame 224.

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

[0047] If any one of the battery units 100 catches fire, the flame will spread in all directions. Since a base plate 221 with a cooling structure is installed under the battery unit 100, the flame can be prevented from spreading downward. Also, since a partition member 223 (or a partition member 132) is located on both sides of the battery unit (or the battery cell stack 50), the flame can be prevented from spreading to both sides of the battery unit. Also, the rear surface of the battery unit 100 usually faces the side wall frame 222 of the pack housing 200. The side wall frame 222 of the recently proposed pack housing 200 is often provided with a venting mechanism for guiding gas and flames in the pack to the outside. Since the rear surface of the battery unit 100 is disposed adjacent to such a venting mechanism, the flame can be prevented from spreading backward of the battery unit 100 to some extent.

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

[0049] The front surface of the battery unit 100 is provided with a terminal portion T, and is therefore highly vulnerable to fire. The cover plate assembly 300 also covers the front surface of the battery unit 100. That is, the cover plate assembly 300 simultaneously covers the top and front surfaces of the battery unit 100, which are most vulnerable to fire, thereby preventing the spread of fire or sparks to adjacent battery units 100.

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

[0051] In this case, there is an advantage that the number of cover plate assemblies 300 required to prevent flame propagation can be reduced. However, since the upper and front of the plurality of battery units are covered with one large upper cover plate 310 and front cover plate 320, the space between the battery units 100 is also partially closed. If the volume of the open space between the battery units 100 is reduced in this manner, the pressure inside the pack during gas venting increases, and the risk of explosion may increase. In addition, if one battery unit 100 is abnormal or ignites, and the cover plate assembly 300 is damaged, the entire cover plate assembly 300 must be removed, which increases the cost of replacing parts.

[0052] Considering this, it is preferable to install a plurality of cover plate assemblies 300 corresponding to the number of battery units 100. That is, each cover plate assembly 300 may cover each battery unit 100 and be coupled to a partition member (or stack partition member 132). As a result, each cover plate assembly 300 can suppress flames occurring on the front and rear surfaces of the battery unit 100 while discharging gas from minute gaps between each cover plate assembly 300 to reduce the pressure inside the pack.

[0053] If the cover plate assembly 300 covers the rear surface of the battery unit 100, the pressure inside the pack may also become high. Therefore, the cover plate assembly 300 of the present invention covers only the upper and front surfaces of the battery unit 100. However, if a suitable pressure relieving means is provided, the cover plate assembly 300 may also cover the rear surface of the battery unit 100. In one embodiment of the present invention, an example in which the rear surface of the battery unit 100 is covered is shown.

[0054] Hereinafter, specific embodiments of the present invention will be described with reference to the drawings.

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

[0056] In this embodiment, a typical battery module 110 is used as the battery unit 100.

[0057] 2 and 3, the battery module 110 includes a battery cell stack 50, a module case 111 that houses 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 be composed of an upper case 111a and a lower case 111b, but is not limited thereto. A bus bar frame is coupled to the inner side of the end plate 112, and terminal parts T derived from the bus bar frame are exposed to the outside on both sides of the end plate 112. Referring to the assembled perspective view of the battery module 110 in FIG. 3, it can be seen that the terminal parts T are exposed to the front surface of the battery module 110. The module case 111 may have a vent hole H to exhaust gas within the module.

[0058] 2 shows a pack housing 200 having a battery module mounting area and a partition member that divides the battery module mounting area into a plurality of areas. The pack housing 200 is composed 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 disposed along an 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 therein, and the gas venting channel C may communicate with a venting opening 221a that is open to the outside.

[0059] 2, the extension direction of the center frame 224 (the width direction of the battery module 110) is indicated as the X direction. The battery modules 110 are arranged in a direction perpendicular to the X direction, which is the longitudinal direction of the battery modules 110. The Z direction is the height direction.

[0060] In addition, partition members 223 that partition a battery module mounting area are installed on the base plate 221. A plurality of partition members 223 are arranged on both sides of the center frame 224 perpendicular to the extension direction of the center frame 224. The battery modules 110 are disposed between the partition members 223 such that the front faces of the battery modules 110 face the center frame 224. An upper surface 223a of the partition members 223 is provided with fastening holes 223b so that the partition members 223 can be fastened to an upper cover plate 310 of a cover plate assembly.

[0061] The cover plate assembly 300 is coupled to the partition wall member 223 while covering an upper surface and a front surface of the battery module 110. As shown in Fig. 2, a plurality of cover plate assemblies 300 of the present embodiment are provided corresponding to the number of battery modules 110, and each cover plate assembly 300 is coupled to the partition wall member 223 while covering each battery unit 100.

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

[0063] 4 and 5, the partition members 223 are in a state of being pre-attached to the pack housing. The battery module 110 is positioned between the partition members 223 and 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 upper surface and the front surface of each battery module 110 , and then the cover plate assembly 300 is coupled to the partition member 223 .

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

[0066] The top cover plate 310 and the front cover plate 320 may be made of the same material or different materials. The front cover plate 320 covers the front of the battery where the terminal portion T is installed, and is therefore preferably made of an electrically insulating material. For example, the front cover plate 320 may be made of an electrically insulating ceramic material such as mica. The top cover plate 310 may also be made of an insulating material such as mica. However, the top cover plate 310 may be made of a metal material with high rigidity and high melting point so as to be resistant to a rising flame. For example, the top cover plate 310 may be made of stainless steel, aluminum or aluminum alloy, or steel.

[0067] Preferably, the front cover plate 320 is made of an insulating material (e.g., mica), and the top cover plate 310 is made of a metal material with a high melting point (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 the bent portion may be used as the front cover plate 320. Alternatively, the cover plate assembly 300 may be made by combining the top cover plate 310 with the front cover plate 320 made of another material. For example, the front cover plate 320 made of mica may be combined with the end of the top cover plate 310 made of steel. The top cover plate 310 and the front cover plate 320 may be fastened together by fastening members such as screws or bolts. Alternatively, the top cover plate 310 and the front cover plate 320 may be bonded together by a predetermined adhesive or by other methods such as welding.

[0068] 4 and 5, one end of the top cover plate 310 is bent vertically to form a joint 312 of a predetermined length, and the front cover plate 320 is bonded or fastened to the inner surface of the joint 312 to join the front cover plate 320 to the top cover plate 310. For example, the end of the top cover plate 310 made of steel is bent to form the bent part as the joint 312, and the front cover plate 320 made of mica is bonded to the inner surface of the bent part to manufacture the cover plate assembly 300. The front cover plate can be made of other materials having insulating properties in addition to the above-mentioned mica. Also, the top cover plate can be made of other materials having fire resistance and fire prevention properties in addition to the above-mentioned metal materials.

[0069] The upper cover plate 310 is formed long enough to cover the entire upper surface of the battery module 110. That is, the length L1 of the upper cover plate 310 should be equal to or longer than the length L2 of the module case 111 plus the thickness of the end plate 112. However, if the upper cover plate 310 is too long, the distance between the front cover plate 320 located at the end of the upper cover plate 310 and the end plate 112 becomes too far, 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 upper cover plate 310 should be equal to or slightly longer than the length L2 of the module case 111 plus the thickness of the end plate. The width W1 of the upper cover plate 310 should be equal to or slightly larger than the width of the battery module 110 so as to completely cover the width W2 of the battery module 110.

[0070] The length (height) of the front cover plate 320 may be the same as the height of the battery module 110 so as to cover the front of the battery module 110. However, the height of the front cover plate 320 may be slightly smaller than the height of the battery module 110, taking into consideration the space inside the pack and the arrangement space of other components. The shapes of the front cover plate 320 in FIG. 4 and FIG. 5 are slightly different. The front cover plate 320 in FIG. 4 has a rectangular shape and covers the front of the battery module 110. Cutouts 321 are provided at both corners of the lower end of the front cover plate 320 in FIG. 5. A coupling protrusion (not shown) for coupling to the bottom corner of the battery module 110 may be formed in the pack housing 200. The cutouts 321 are provided to avoid the coupling protrusion when it is installed. That is, when a corner of the battery module 110 is coupled to the coupling protrusion of the pack housing 200, the coupling protrusion is located in the space of the cutout 321, and the front cover plate 320 can be installed to fit snugly to the shapes of the battery module 110 and the coupling protrusion. The front cover plate 320 is in close contact with the end plate 112 on the front side of the module or is spaced a predetermined distance from the end plate to protect the terminal part T and other electrical components installed on the end plate.

[0071] The upper cover plate 310 is coupled to the upper surface 223a of the partition member 223, so that the cover plate assembly 300 is coupled to the partition member 223. To this end, the upper cover plate 310 may have a plurality of fastening portions 311 along both sides of the cover plate. The fastening portions may have fastening holes 311a. The fastening portions 311 may be provided at intervals along both sides of the upper cover plate 310. As shown in FIG. 4 and FIG. 5, the fastening portions 311 of adjacent upper cover plates 310 may be configured to be interlocked with each other. That is, when the fastening portions 311 of the sides of the upper cover plates 310 of adjacent cover plate assemblies 300 are positioned to interlock with the intervals between the fastening portions 311 of the sides of the upper cover plates 310 of one cover plate assembly 300, the fastening portions of the adjacent upper cover plates 310 are placed on the same partition member 223. Therefore, the space required for coupling can be reduced by fastening (coupling) the fastening portions 311 of adjacent upper cover plates 310 to the upper surface of the partition member 223. Also, the upper cover plates 310 of adjacent cover plate assemblies 300 are coupled to each other by being interlocked with each other, thereby reducing the space occupied by the cover plate assemblies 300 in the pack and at the same time, the cover plate assemblies 300 can be more firmly coupled to the partition member 223. However, as shown in FIG 2, the fastening portions 311 of the upper cover plates 310 of the cover plate assemblies 300 coupled to the partition member 223 disposed at the outermost position in the X direction do not engage with the fastening portions 311 of the adjacent upper cover plates 310 because there is no adjacent upper cover plate 310.

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

[0073] 6, the battery modules 110 are arranged side by side with a partition member 223 between them. Terminal portions T are located at the upper ends of both sides of an end plate 112 installed in the front of the battery module 110. The terminal portions T of adjacent battery modules 110 with the partition member 223 between them are electrically connected to each other by an interbus bar B. In order to secure a space in which the interbus bar B can be coupled, an edge portion of the front end portion of the partition member 223 located between the battery modules 110 is cut out. The interbus bar passes through the cutout portion of this edge to connect the terminal portions T of the battery modules 110 on both sides to each other (see FIGS. 6(a) and 6(b)).

[0074] After the inter-bus bar B is connected, the cover plate assembly 300 is seated on the top of the battery modules 110, and the fastening portion 311 of the cover plate assembly 300 is fastened to the upper surface 223a of the partition member 223 between the battery modules 110 (see FIG. 6(c)).

[0075] 7 shows that a plurality of cover plate assemblies 300 are respectively coupled to the partition members 223 between the battery modules 110 and respectively mounted on the plurality of battery modules 110. Then, the upper cover 210 is fastened to the lower pack housing 220 so that the upper cover 210 covers the cover plate assemblies 300, thereby completing the assembly of the battery pack of the present invention.

[0076] FIG. 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 to suppress the flame propagation to the upper part of the module. In addition, the front cover plate 320 covers the front surface of the module. In FIG. 8, it is assumed that the electrode leads 51a, 51b of the battery cell 51 in the module are bidirectional pouch cells led out to both sides of the cell. However, the present invention can also be applied to a battery module composed of unidirectional pouch cells led out to one side of the cell. Electrode leads 51a, 51b are led out to the front and rear of the battery cell, and the electrode leads are electrically connected to the interbus bar or terminal bus bar T. The front cover plate 320 is positioned to cover the terminal bus bar (terminal portion T) on the front surface of the battery module 110, so that the terminal portion T is protected from the flame. As shown in the figure, a gas venting channel C of the sidewall frame 222 is located at the rear surface of the battery module 110, so that a flame occurring at 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 FIG. 9 is a perspective view showing a coupling relationship between a cover plate assembly 300' and a battery module 110 applied to another embodiment of the present invention, and FIG. 10 is a side sectional view showing a battery pack 2000 according to another embodiment of the present invention.

[0078] The configurations of the battery module 110 and the pack housing 200 applied to this embodiment are the same as those of the first embodiment. Also, the cover plate assembly 300' includes a top cover plate 310 and a front cover plate 320. A description of the same configurations as those of 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 Fig. 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 that is vertically coupled to the other end of the top cover plate 310 and covers the rear of the battery module 110. As described above, if the rear of the battery module 110 is covered in addition to the top and front, there is a risk that the pressure inside the pack will increase during heat propagation.

[0080] In this embodiment, a number of vent holes 331 are formed in the rear cover plate 330 to prevent pressure build-up within the pack during heat propagation conditions.

[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 with insulating function. The rear cover plate 330 may be made of the same material and shape as the front cover plate 320.

[0082] The joining method between the rear cover plate 330 and the top cover plate 310 may also adopt the joining method between the top cover plate 310 and the front cover plate 320. In Fig. 9, the other end of the top cover plate 310 is bent vertically, and the rear cover plate 330 is joined to the bent end.

[0083] Since a plurality of vent holes 331 are formed in the rear cover plate 330, when gas is generated in the pack during heat transfer and the gas pressure increases, the gas can be discharged through the vent holes 331 to prevent the pressure from increasing. In particular, by connecting the vent holes 331 of the rear cover plate 330 to the outside, gas can be easily discharged.

[0084] As shown in FIG. 10, when a gas venting channel C is formed in the sidewall frame 222 of the pack housing 200, the rear cover plate 330 may be installed so that the venting hole 331 of the rear cover plate 330 faces or contacts the inlet 222c of the gas venting channel. In the example of FIG. 10, when a flame occurs due to thermal runaway of a specific 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 the adjacent battery module 110. Furthermore, the rear cover plate 330 of the cover plate assembly 300 may prevent the flame from spreading behind the battery module 110. In this case, when gas is generated from the battery module 110, the gas may be discharged to the outside through the venting hole 331 of the rear cover plate 330 and the gas venting channel C of the sidewall frame 222 connected thereto.

[0085] Therefore, according to the present embodiment, there is an advantage in that the effect of preventing flame propagation within the pack can be maximized while preventing a pressure rise within the pack.

[0086] Third embodiment 11 and 12 are perspective views showing an example of a module-less cell block as a battery unit 100, and FIG. 13 is a perspective view showing a battery pack 3000 according to another embodiment of the present invention.

[0087] As described above, the battery unit 100 may employ the cell blocks 120, 120' having a module-less structure in addition to the battery module 110.

[0088] 11 discloses a battery cell stack 50 and a cell block 120 in which bus bar assemblies 121 are coupled to the front and rear surfaces of the stack. The cell block 120 has a moduleless structure in which the module case 111 that covers the top, bottom, left and right surfaces of the battery cell stack 50 is not present at all.

[0089] 12 discloses a cell block 120' including a battery cell stack 50, bus bar assemblies 121 coupled to the front and rear surfaces of the stack, and side support plates 123 coupled to both side surfaces of the battery cell stack 50. The cell block 120' in FIG 12 has a moduleless structure in which the top and bottom surfaces of the battery cell stack 50 are open and part of the module case 111 is missing.

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

[0091] A bus bar assembly 121 is coupled to the electrode leads on the front and rear surfaces of the battery cell stack 50. The bus bar assembly is provided with a terminal portion T.

[0092] 13 shows that such a moduleless cell block 120' is installed in a pack housing 200. As in the first embodiment, the pack housing 200 has a battery unit (cell block) mounting area and a partition member 223 that divides the cell block mounting area. Also, as in FIG. 2, a center frame 224 and a plurality of partition members 223 are arranged perpendicular to the center frame 224.

[0093] The cell blocks 120 ′ are disposed between the partition members 223 such that the front surface of the cell block 120 ′ on which the terminal portions T are installed faces the center frame 224 .

[0094] The cell block 120′ may be mounted 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 the volume. In this case, the side support plates 123 may be fastened to the partition members 223 by a fastening member or the like.

[0095] In this embodiment, a cover plate assembly 300 having a top cover plate 310 and a front cover plate 320 is seated on the cell block 120' from the top of each cell block. The top cover plate 310 is coupled to the top of the partition wall member 223 that divides the cell block, and protects the top and front of the cell block 120 from fire.

[0096] Since the battery pack 3000 of the present embodiment relates to a cell block having a module-less structure without all or a part of the module case 111, the cover plate assembly 300 exerts a greater function. That is, the upper cover plate 310 not only prevents fire, but also covers the upper part of the cell block without the module case 111 to protect the upper part of the battery cell stack 50. That is, the cell blocks 120, 120' having a module-less structure can reduce the number of related parts and increase the energy density since the module case is eliminated, but the cell blocks are partially exposed, making them vulnerable to contamination or fire within the pack. The cover plate assembly 300 can effectively protect the cell blocks from contaminants and fire within the pack by covering such a cell block having a module-less structure.

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

[0098] In this embodiment, similar to the third embodiment, the battery unit 100 is a cell block 130 having a moduleless structure that lacks a portion of a module case that houses the battery cell stack 50. However, unlike the first to third embodiments, this embodiment differs in that the cover plate assembly 300 is not coupled to the partition member 223 of the pack housing 200 but is instead coupled to the cell block 130 itself.

[0099] Referring to FIG. 14, the cell block 130 of the present embodiment includes a battery cell stack 50, a bus bar assembly 131 coupled to a front side of the battery cell stack 50, and a first side support plate 132A and a second side support plate 132B coupled to both side sides of the battery cell stack 50.

[0100] The bus bar assembly 131 is provided with terminal bus bars T on both upper sides thereof.

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

[0102] In particular, the cell block 130 of this embodiment includes uniquely constructed first and second side support plates 132A, 132B that can couple adjacent cell blocks together.

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

[0104] The first side support plate 132A and the second side support plate 132B have complementary structures that mesh with each other. For example, as shown in FIG. 14, the first side support plate 132A has a step structure with a protrusion A at the upper side and a recess B at the lower side. Meanwhile, the second side support plate 132B has a step structure with a protrusion A' at the lower side and a recess B' at the upper side. The step structure of the first side support plate 132A and the step structure of the second side support plate 132B mesh with each other to match. Therefore, the first side support plate 132A of one cell block 130 and the second side support plate 132B of the adjacent cell block 130 facing it are meshed with each other, and the first side support plate 132A and the second side support plate 132B are coupled with each other by a fastening member, so that the adjacent cell blocks can be coupled with each other. Each side support plate has 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 Fig. 14, a plurality of fastening holes 133a are formed through the upper surface 133 of the protruding portion of the first side support plate 132A, and a plurality of fastening holes 133a' are formed through the protruding portion A' at the lower side of the second side support plate 132B at positions corresponding to the above-mentioned fastening holes. Therefore, the first side support plate and the second side support plate can be joined together by connecting them so that fastening members such as bolts pass through the fastening holes of the first side support plate 132A and the second side support plate 132B.

[0105] 15 shows that the first side support plate 132A and the second side support plate 132B of adjacent cell blocks are coupled to each other through the above-mentioned coupling process. As shown in FIG. 15, the combined body of the first side support plate and the second side support plate becomes a stack partition wall member 132 that divides adjacent battery cell stacks 50. In this embodiment, the cover plate assembly 300 may be coupled to an upper surface of the stack partition wall member 132. That is, a fastening portion 311 of an upper cover plate 310 of the cover plate assembly 300 may be fastened to an upper surface 133 of the stack partition wall member 132. The stack partition wall member 132 is different from the other embodiments in that it is not a partition wall member 223 previously installed in the pack housing 200, but is formed by coupling the cell blocks.

[0106] 16 shows a pack housing 200 including a center frame 224 extending across the cell block mounting area. Unlike the pack housing 200 of FIG. 2, this pack housing 200 does not have a partition member 223 installed in the cell block mounting area. As shown in FIG. 15, adjacent cell blocks 130 can form two rows of cell block assemblies on both sides of the center frame 224 by complementary coupling of opposing side support plates as shown in FIG. 16. The cell block assemblies are installed on both sides of the center frame 224 so that a plurality of cell blocks are vertically arranged on the center frame 224 and the front faces of the cell blocks 130 face the center frame 224.

[0107] The cell block or cell block assembly may be fixed to the pack housing 200 by coupling the laminate partition member 132 to a base plate 221 of the pack housing 200. For example, when fastening members 133a, 133b are coupled through fastening holes in the first side support plate 132A and the second side support plate 132B shown in Fig. 14, ends of the fastening members may be coupled to the base plate 221, thereby simultaneously coupling the cell block and coupling the cell block to the base plate 221. Alternatively, separate fastening holes may be formed on the upper surface (upper surface of the first side support plate) of the laminate partition member 132 composed of the first side support plate 132A and the second side support plate 132B, and the fastening members may be inserted into the fastening holes to be fastened to the base plate 221.

[0108] As shown in FIG. 17, when the cell block is coupled to the pack housing 200, the cover plate assembly 300 may be coupled to the cell block. That is, the upper cover plate 310 of the cover plate assembly 300 may be fastened on the stack partition member 132 formed by coupling the first side support plate 132A and the second side support plate 132B between adjacent battery cell stacks 50. If necessary, the fastening holes of the first side support plate and the second side support plate and the fastening holes of the fastening portion of the upper cover plate 310 may be formed at the same position. In this case, the fastening holes of the first side support plate and the second side support plate and the fastening holes of the upper cover plate 310 may be aligned, and the same fastening member may be inserted into the aligned fastening holes to be fastened. In this way, the coupling of the cell block and the coupling of the cover plate assembly 300 may be achieved simultaneously.

[0109] According to the present embodiment, not only is the structure of the battery pack 1000 simplified by using the module-less cell blocks, but also the laminated barrier member 132 can be formed by combining the cell blocks without a separate barrier member 223, so that the structure of the battery pack 1000 is further simplified, thereby further improving the energy density.

[0110] Meanwhile, in the second embodiment, a case has been described in which the battery module 110 is used as the battery unit 100. However, the cover plate assembly 300 of the second embodiment may also be applied when using the cell blocks 120, 120', 130 having a moduleless structure as in the third and fourth embodiments. That is, in the battery packs 1000 of the third and fourth embodiments, the cover plate assembly 300 including the rear cover plate 330 may be fastened to the partition member 223 or the laminate partition member 132 to prevent flame propagation to the rear of the cell block.

[0111] The above description is merely illustrative of the technical idea of ​​the present invention, and various modifications and variations are possible within the scope of the essential characteristics of the present invention if one has ordinary knowledge in the technical field to which the present invention belongs. Therefore, the drawings disclosed in the present invention are for the purpose of explanation, not for the purpose of limiting the technical idea of ​​the present invention, and the scope of the technical idea 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 ideas within the scope equivalent thereto should be interpreted as being included in the scope 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 part 311a: Fastening hole 312: Joint part (bending part) 320: Front cover plate 321: Incision 330: Rear cover plate 331: Venting Hall 1000, 2000, 3000, 4000: Battery pack

Claims

1. a plurality of battery units each including a battery cell stack and each including 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 areas between the partition members; a cover plate assembly covering an upper surface and a front surface of the battery unit and coupled to the partition member.

2. The battery unit is 13. The battery pack of claim 1, which is a battery module including a module case that houses the battery cell stack and end plates coupled to front and rear surfaces of the module case.

3. The battery unit is a bus bar assembly is coupled to a front surface and a rear surface of the battery cell stack, and a module case accommodating the battery cell stack is entirely or partially absent.

13. The battery pack according to claim 1, wherein a terminal portion is provided on a bus bar assembly coupled to a front surface of the battery cell stack.

4. The module-less structure cell block comprises: Side support plates are coupled to both sides of the battery cell stack, The battery pack according to claim 3 , wherein both an upper surface and a lower surface of the battery cell stack, except for a surface where the side support plate and the bus bar assembly are coupled, are open.

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

6. The cover plate assembly is provided in a plurality of pieces corresponding to the number of the battery units, 10. The battery pack of claim 1, wherein each cover plate assembly covers a respective battery unit and is coupled to a bulkhead member.

7. 7. The battery pack of claim 1, wherein the cover plate assembly includes a top cover plate covering a top surface of the battery unit, and a front cover plate vertically coupled to one end of the top cover plate and covering a front surface of the battery unit.

8. The battery pack of claim 7 , wherein a plurality of fastening portions protrude at intervals along both sides of the top cover plate, the fastening portions being coupled to an upper surface of the partition member.

9. 9. The battery pack of claim 8, wherein the fastening portions on the top cover plate sides of adjacent cover plate assemblies are positioned to interlock with the gaps between the fastening portions on the top cover plate sides of one cover plate assembly, thereby allowing the fastening portions of the top cover plates of adjacent cover plate assemblies to be respectively coupled onto the same bulkhead member.

10. 8. The battery pack of claim 7, wherein the front cover plate is formed from an electrically insulating material.

11. the cover plate assembly further includes a rear cover plate vertically coupled to the other end of the top cover plate to cover a rear surface of the battery unit, The battery pack according to claim 7 , wherein the rear cover plate has a plurality of vent holes formed therein.

12. a plurality of cell blocks each including a battery cell stack, a bus bar assembly coupled to a front surface of the battery cell stack, and a side support plate coupled to both side surfaces of the battery cell stack; a pack housing having a cell block mounting area, the pack housing having a plurality of the cell blocks fixedly mounted in the cell block mounting area; a cover plate assembly covering a top and a front surface of the cell block and coupled to the cell block.

13. The pack housing includes a center frame extending across the cell block mounting area, The battery pack according to claim 12 , wherein a plurality of cell blocks are arranged perpendicular to an extension direction of the center frame, with front surfaces of the cell blocks facing the center frame.

14. the side support plate includes a first side support plate coupled to one side of the battery cell stack and a second side support plate coupled to the other side of the battery cell stack, the first side support plate and the second side support plate having complementary structures that are interdigitated with each other, a first side support plate of one of the two opposing battery cell stacks and a second side support plate of the other battery cell stack are engaged with each other to couple adjacent cell blocks to each other; The battery pack according to claim 12 , wherein the first side support plate and the second side support plate, which are coupled together, are coupled to the cell block mounting area, thereby fixedly installing the cell block to the pack housing.

15. the first side support plate and the second side support plate coupled together form stack partition members that partition each of the battery cell stacks; The battery pack according to claim 14 , wherein the cover plate assembly is coupled to an upper surface of the laminate partition member.

Images