Battery module and battery pack including same

Abstract

A battery module according to an embodiment of the present invention includes a battery cell stack including a first battery cell stack and a second battery cell stack in which a plurality of battery cells are stacked, and a center bus bar assembly disposed between the first battery cell stack and the second battery cell stack. The first battery cell stack and the second battery cell stack are disposed along a direction perpendicular to a direction in which the battery cells are stacked in the first battery cell stack and the second battery cell stack. Any one of the battery cells included in the first battery cell stack and any one of the battery cells included in the second battery cell stack are electrically connected to each other through a center bus bar included in the center bus bar assembly to form a double cell structure, and the battery cell stack includes at least one of the double cell structures.

Description

[Technical Field]

[0001] [Cross-Citation of Related Applications] This application claims the benefit of priority based on Korean Patent Application No. 10-2022-0102827 dated August 17, 2022, and all contents disclosed in the documents of that Korean patent application are incorporated herein by reference.

[0002] The present invention relates to a battery module and a battery pack including the same, and more particularly to a battery module with improved energy density and a battery pack including the same. [Background technology]

[0003] In modern society, as the use of portable devices such as mobile phones, laptops, video cameras, and digital cameras has become commonplace, there has been active development of technologies related to these mobile devices. Furthermore, rechargeable secondary batteries are being used as power sources for electric vehicles (EVs), hybrid electric vehicles (HEVs), plug-in hybrid electric vehicles (P-HEVs), and other vehicles as a solution to air pollution caused by existing gasoline-powered vehicles that use fossil fuels, and so there is an increasing need for development of secondary batteries.

[0004] Currently commercially available secondary batteries include nickel-cadmium batteries, nickel-metal hydride batteries, nickel-zinc batteries, and lithium secondary batteries. Of these, lithium secondary batteries are attracting attention because they have the advantages of being free to charge and discharge, having a very low self-discharge rate, and having a high energy density, as they have almost no memory effect compared to nickel-based secondary batteries.

[0005] Such lithium secondary batteries mainly use lithium-based oxides and carbon materials as the positive and negative electrode active materials, respectively, and include an electrode assembly in which a positive electrode plate and a negative electrode plate coated with the positive and negative electrode active materials are arranged with a separator sandwiched therebetween, and a battery case that hermetically houses the electrode assembly together with an electrolyte.

[0006] Generally, lithium secondary batteries can be classified into can-type secondary batteries, in which an electrode assembly is housed in a metal can, and pouch-type secondary batteries, in which an electrode assembly is housed in a pouch made of an aluminum laminate sheet, depending on the shape of the exterior material.

[0007] In the case of secondary batteries used in small devices, two to three battery cells are arranged, while in the case of secondary batteries used in medium- to large-sized devices such as automobiles, a battery module in which multiple battery cells are electrically connected is used. In such battery modules, multiple battery cells are connected to each other in series or parallel to form a battery cell stack, thereby improving capacity and output. In addition, one or more battery modules can be attached with various control and protection systems such as a battery disconnect unit (BDU), a battery management system (BMS), and a cooling system to form a battery pack.

[0008] When constructing a battery pack, it is common to first construct a battery module, and then add various control and protection systems such as a battery disconnect unit (BDU), a battery management system (BMS), and a cooling system to the battery module to construct the battery pack. In the case of a conventional battery pack, the battery module is placed in a housing structure such as a pack tray before being manufactured and the battery pack is installed in a vehicle or the like.

[0009] Recently, research is ongoing into battery modules and battery packs that improve space utilization to increase energy density within a limited space and make products lighter. Summary of the Invention [Problem to be solved by the invention]

[0010] The present invention provides a battery module and a battery pack including the same that can increase energy density and reduce weight by improving the connection method of internal battery cells.

[0011] However, the problems to be solved by the embodiments of the present invention are not limited to the above problems, and can be variously expanded within the scope of the technical ideas included in the present invention. [Means for solving the problem]

[0012] A battery module according to one embodiment of the present invention includes a battery cell stack including a first battery cell stack and a second battery cell stack, each of which includes a plurality of stacked battery cells, and a center bus bar assembly disposed between the first battery cell stack and the second battery cell stack. The first battery cell stack and the second battery cell stack are disposed perpendicular to the stacking direction of the battery cells in the first battery cell stack and the second battery cell stack. Any one battery cell included in the first battery cell stack and any one battery cell included in the second battery cell stack are electrically connected through a center bus bar included in the center bus bar assembly to form a double cell structure, and the battery cell stack includes at least one of the double cell structures.

[0013] The battery cells may be pouch cells and may include electrode leads protruding in both directions, and the electrode lead of any one battery cell included in the first battery cell stack and the electrode lead of any one battery cell included in the second battery cell stack may be electrically connected via the center bus bar to form the double cell structure.

[0014] The electrode lead of any one of the battery cells included in the first battery cell stack and the electrode lead of any one of the battery cells included in the second battery cell stack may be welded to the center bus bar.

[0015] A plurality of center bus bars may be arranged, and the center bus bar assembly may further include spacers positioned between the center bus bars and occupying spaces between the center bus bars.

[0016] A plurality of center bus bars may be arranged, and a protrusion and a coupling hole may be formed on one surface and the other surface of each center bus bar, and a through hole may be formed in each center bus bar. The protrusion of any one of the spacers may pass through the through hole of the center bus bar and then be inserted into the coupling hole of another spacer.

[0017] A plurality of the spacers may be arranged, and the spacers may be assembled together by engaging hooks.

[0018] The battery module may further include a pair of terminal bus bar assemblies disposed on opposite ends of the center bus bar assembly between the first and second battery cell stacks. The terminal bus bar assembly may include a terminal bus bar, and the terminal bus bar may include a first portion connected to an electrode lead of the battery cell and a second portion extending from the first portion and exposed to the outside.

[0019] The electrode lead of the battery cell arranged at the outermost position in one direction of the first battery cell stack may be connected to the first portion of the terminal bus bar included in one of the terminal bus bar assemblies, and the electrode lead of the battery cell arranged at the outermost position in the other direction of the second battery cell stack may be connected to the first portion of the terminal bus bar included in another of the terminal bus bar assemblies.

[0020] The terminal bus bar assembly may further include a terminal spacer that faces one side of the first portion of the terminal bus bar, and a terminal insulating plate that covers the other side of the first portion of the terminal bus bar.

[0021] The battery module may further include a first external bus bar frame located on one side of the first battery cell stack and a second external bus bar frame located on one side of the second battery cell stack. Electrode leads protruding from the battery cells included in the first battery cell stack toward the first external bus bar frame may be connected to a first external bus bar attached to the first external bus bar frame. Electrode leads protruding from the battery cells included in the second battery cell stack toward the second external bus bar frame may be connected to a second external bus bar attached to the second external bus bar frame.

[0022] The first external bus bar frame may be positioned in a direction opposite to a direction in which the center bus bar assembly is disposed relative to the first battery cell stack, and the second external bus bar frame may be positioned in a direction opposite to a direction in which the center bus bar assembly is disposed relative to the second battery cell stack.

[0023] A first sensing unit and a second sensing unit for voltage sensing may be attached to the first external bus bar frame and the second external bus bar frame, respectively. A circuit unit may connect at least one of the first sensing unit or the second sensing unit to the center bus bar.

[0024] The center bus bar may include a first portion connected to the electrode lead of the battery cell and a second portion extending from the first portion to be connected to the circuit unit, and the circuit unit may extend to a lower end of the center bus bar assembly to be connected to the second portion of the center bus bar.

[0025] The battery module may further include an upper insulating member located on the center bus bar assembly and including an electrically insulating material.

[0026] The upper insulating member may include a first wall portion facing the first battery cell stack, a second wall portion facing the second battery cell stack, and a bottom portion connecting the first wall portion and the second wall portion and facing the center bus bar assembly.

[0027] The center bus bar assembly may further include a spacer positioned between the center bus bars to occupy a space between the center bus bars. The spacer and the upper insulating member may be assembled by engaging a hook.

[0028] The battery module may further include a lower insulating member located below the center bus bar assembly and including an electrically insulating material.

[0029] The center bus bar assembly may further include a spacer positioned between the center bus bars to occupy a space between the center bus bars. The spacer and the lower insulating member may be assembled by engaging a hook.

[0030] A battery pack according to an embodiment of the present invention may include the battery module. [Effects of the Invention]

[0031] According to an embodiment of the present invention, a double cell structure is formed by connecting battery cells in the longitudinal direction using a center bus bar assembly, thereby improving space utilization in the longitudinal direction, thereby increasing the energy density and reducing the weight of a battery module and a battery pack including the same.

[0032] The effects of the present invention are not limited to those mentioned above, and other effects not mentioned will be clearly understood by those skilled in the art from the description of the claims. [Brief explanation of the drawings]

[0033] [Figure 1] FIG. 1 is a perspective view showing a battery module according to an embodiment of the present invention. [Figure 2] FIG. 2 is an exploded perspective view of the battery module of FIG. [Figure 3] FIG. 3 is a side view showing one of the battery cells included in the battery module of FIG. [Figure 4] FIG. 4 is a perspective view and a side view, respectively, showing a dual cell structure according to one embodiment of the present invention. [Figure 5] FIG. 5 is a perspective view and a side view, respectively, showing a dual cell structure according to one embodiment of the present invention. [Figure 6] FIG. 6 is a perspective view showing a center bus bar assembly and a terminal bus bar assembly included in the battery module of FIG. [Figure 7]FIG. 7 is an exploded perspective view showing a center bus bar assembly according to an embodiment of the present invention. [Figure 8] 8(a) and 8(b) are views showing the center bus bar and spacers included in the center bus bar assembly of FIG. 7 from various angles. [Figure 9] 9(a) and 9(b) are views showing the spacer included in the center bus bar assembly of FIG. 7 from various angles. [Figure 10] 10(a) and 10(b) are exploded perspective views showing the terminal bus bar assembly of FIG. [Figure 11] FIG. 11 is an exploded perspective view illustrating a connection form between a terminal bus bar assembly and one of the battery cells according to an embodiment of the present invention. [Figure 12] FIG. 12 is an exploded perspective view showing a battery module according to a comparative example of the present invention. [Figure 13] FIG. 13 is a perspective view showing a first external bus bar frame, a second external bus bar frame, a first circuit unit, and a second circuit unit according to one embodiment of the present invention. [Figure 14] FIG. 14 is a front view of the first external bus bar frame of FIG. 13 as viewed from the direction "B." [Figure 15] FIG. 15 is a rear view of the second external bus bar frame of FIG. 13 as seen from the direction "C." [Figure 16] FIG. 16 is a schematic diagram illustrating an HV connection form and an LV connection form in a battery module according to an embodiment of the present invention. [Figure 17] FIG. 17 is a perspective view showing a center bus bar assembly, an upper insulating member, and a lower insulating member according to an embodiment of the present invention. [Figure 18] 18(a), (b), and (c) are views showing the upper insulating member in FIG. 17 from various angles. [Figure 19] FIG. 19 is a partial view illustrating a coupling form between the fastening hole of the upper insulating member and the second hook of the spacer. [Figure 20]20 is a perspective view showing the lower insulating member of FIG. [Figure 21] FIG. 21 is an enlarged partial view of part "A" in FIG. [Figure 22] FIG. 22 is an enlarged partial view showing how a battery module is fixed to a mounting beam according to an embodiment of the present invention. [Figure 23] 23(a) and 23(b) are partial views showing the connection between the battery cells and the center bus bar and the connection between the battery cells and the terminal bus bars, respectively. [Figure 24] 24(a), (b), and (c) are partial views illustrating the process of assembling the terminal bus bar and the terminal spacer. [Figure 25] FIG. 25 is a partial view illustrating the process of stacking double cells. DETAILED DESCRIPTION OF THE INVENTION

[0034] DETAILED DESCRIPTION OF THE INVENTION The present invention may be embodied in many different forms and is not limited to the embodiments set forth herein.

[0035] In order to clearly describe the present invention, parts that are not relevant to the description will be omitted, and the same reference numerals will be used throughout the specification to refer to the same or similar components.

[0036] Furthermore, the size and thickness of each component shown in the drawings are arbitrarily shown for the convenience of explanation, and the present invention is not necessarily limited to those shown. Thicknesses are exaggerated in the drawings to clearly show various layers and regions. Also, in the drawings, the thicknesses of some layers and regions are exaggerated for the convenience of explanation.

[0037] Furthermore, when a layer, film, region, plate, or other part is said to be "on" or "above" another part, this includes not only the case where it is "directly above" the other part, but also the case where there is another part in between. Conversely, when a part is said to be "directly above" another part, it means that there is no other part in between. Furthermore, being "on" or "above" a reference part means being located above or below the reference part, and does not necessarily mean being located "on" or "above" in the direction opposite to gravity.

[0038] Furthermore, throughout the specification, when a part is described as "comprising" a certain element, this does not mean that it excludes other elements, but that it may further include other elements, unless otherwise specified to the contrary.

[0039] Furthermore, throughout the specification, "on a plane" means when the subject part is viewed from above, and "on a cross section" means when the subject part is cut vertically and viewed from the side.

[0040] Fig. 1 is a perspective view showing a battery module according to an embodiment of the present invention, Fig. 2 is an exploded perspective view of the battery module of Fig. 1, and Fig. 3 is a side view showing one of the battery cells included in the battery module of Fig. 2.

[0041] 1 to 3, a battery module 100 according to an embodiment of the present invention includes a battery cell stack 120 including a first battery cell stack 120a and a second battery cell stack 120b in which a plurality of battery cells 110 are stacked, and a center bus bar assembly 400 disposed between the first battery cell stack 120a and the second battery cell stack 120b.

[0042] First, the battery cell 110 may be a pouch-type battery cell and may include electrode leads 111 and 112 protruding in both directions. Such a pouch-type battery cell may be formed by housing an electrode assembly in a pouch case made of a laminate sheet including a resin layer and a metal layer, and then bonding the outer periphery of the pouch case. Such a battery cell 110 may have a rectangular sheet structure. Specifically, the battery cell 110 according to this embodiment has a structure in which two electrode leads 111 and 112 protrude from one end 114a and the other end 114b of the battery body 113, respectively. More specifically, the electrode leads 111 and 112 may protrude in opposite directions, and one of the electrode leads 111 and 112 may be a positive electrode lead 111 and the other a negative electrode lead 112. In this embodiment, the direction between the positive electrode lead 111 and the negative electrode lead 112 of the battery cell 110 is referred to as the length direction of the battery cell 110. For example, referring to FIGS. 2 and 3, the direction parallel to the x-axis may correspond to the length direction of the battery cell 110.

[0043] The battery cell 110 can be manufactured by bonding one end 114a and the other end 114b of the battery case 114 to one side 114c connecting the one end 114a and the other end 114b, with an electrode assembly (not shown) housed in the battery case 114. In other words, the battery cell 110 according to one embodiment of the present invention has a total of three sealing portions, which are sealed by a method such as fusion, and the remaining other side may be formed as a connecting portion 115.

[0044] A plurality of such battery cells 110 may be configured, and the plurality of battery cells 110 may be stacked so as to be electrically connectable to each other to form a battery cell stack 120. The battery cell stack 120 includes a first battery cell stack 120a and a second battery cell stack 120b. In particular, the battery cells 110 may be stacked in one direction while remaining upright, with one surface of the battery bodies 113 of the battery cells 110 facing each other. FIG. 2 shows, as an example, a state in which a plurality of battery cells 110 are stacked in a direction parallel to the y-axis. When a plurality of battery cells 110 are stacked in this way in a direction parallel to the y-axis, the electrode leads 111 and 112 of a certain battery cell 110 may protrude along the x-axis direction and the -x-axis direction, respectively.

[0045] In one region, a plurality of battery cells 110 may be stacked in a direction parallel to the y-axis to form a first battery cell stack 120a, and in another region, a plurality of battery cells 110 may be stacked in a direction parallel to the y-axis to form a second battery cell stack 120b.

[0046] The battery case 114 generally has a laminate structure of a resin layer / a metal thin film layer / a resin layer. For example, if the surface of the battery case is made of an O(oriented)-nylon layer, it tends to slip due to external impact when stacking multiple battery cells to form a medium- to large-sized battery module. Therefore, to prevent this and maintain a stable stacked structure of the battery cells, an adhesive material such as a pressure-sensitive adhesive such as double-sided tape or a chemical adhesive that bonds through a chemical reaction during bonding can be attached to the surface of the battery case to form the first battery cell stack 120a and the second battery cell stack 120b.

[0047] Meanwhile, the first battery cell stack 120a and the second battery cell stack 120b are arranged along a direction perpendicular to the stacking direction of the battery cells 110 in the first battery cell stack 120a and the second battery cell stack 120b. In other words, the first battery cell stack 120a and the second battery cell stack 120b may be arranged along the direction in which the electrode leads 111 and 112 protrude from the battery cell 110. That is, the first battery cell stack 120a and the second battery cell stack 120b are arranged along the length direction of the battery cell 110. For example, as shown in FIG. 2, when a plurality of battery cells 110 are stacked along a direction parallel to the y-axis to form the first battery cell stack 120a and the second battery cell stack 120b, the first battery cell stack 120a and the second battery cell stack 120b may be arranged along a direction parallel to the x-axis.

[0048] The double cell structure according to this embodiment will be described in detail below with reference to FIGS.

[0049] 4 and 5 are a perspective view and a side view, respectively, showing a dual cell structure according to an embodiment of the present invention. Specifically, in FIG. 2, one of the battery cells 110 included in the first battery cell stack 120a and one of the battery cells 110 included in the second battery cell stack 120b are shown connected to each other.

[0050] 2 to 5, the center bus bar assembly 400 according to this embodiment includes a center bus bar 410. Other configurations of the center bus bar assembly 400 will be described again with reference to FIGS.

[0051] Any one of the battery cells 110 included in the first battery cell stack 120a and any one of the battery cells 110 included in the second battery cell stack 120b are electrically connected through a center bus bar 410 included in the center bus bar assembly 400 to form a double cell 110dc structure.

[0052] As described above, the center bus bar assembly 400 is located between the first battery cell stack 120a and the second battery cell stack 120b. The battery cells 110 included in the first battery cell stack 120a and the battery cells 110 included in the second battery cell stack 120b are connected via the center bus bar 410 included in the center bus bar assembly 400. In FIGS. 4 and 5 , the battery cells 110 arranged in the x-axis direction are the battery cells included in the first battery cell stack 120a, and the battery cells 110 arranged in the -x-axis direction are the battery cells included in the second battery cell stack 120b. The electrode lead 112 of any one battery cell 110 included in the first battery cell stack 120a and the electrode lead 111 of any one battery cell 110 included in the second battery cell stack 120b are electrically connected via the center bus bar 410, thereby forming a double cell 110dc structure. For example, the negative electrode lead 112 of any one of the battery cells 110 included in the first battery cell stack 120a and the positive electrode lead 111 of any one of the battery cells 110 included in the second battery cell stack 120b may be electrically connected via the center bus bar 410, thereby realizing a series connection between the battery cells 110. There are no particular limitations on the method of electrically connecting the electrode leads 111, 112 and the center bus bar 410, and welding may be used, for example.

[0053] In the battery module 100 according to this embodiment, the first battery cell stack 120a and the second battery cell stack 120b, which are arranged along the length of the battery cells 110, are electrically connected to each other by directly connecting the electrode leads 111 and 112 via a center bus bar 410 without using a plate-shaped bus bar frame or insulating plate therebetween. The double cell 110dc structure according to this embodiment refers to a structure in which the electrode leads 111 and 112 of two battery cells 110 arranged along the length of the battery cells 110 are directly connected via the center bus bar 410, as shown in FIGS. 4 and 5 . The battery cell stack 120 according to this embodiment includes at least one such double cell 110dc structure.

[0054] The structure of the center bus bar assembly 400 according to this embodiment will be described in detail below with reference to FIGS. 6 to 8. FIG.

[0055] Figure 6 is a perspective view showing a center bus bar assembly and a terminal bus bar assembly included in the battery module of Figure 2. Figure 7 is an exploded perspective view showing a center bus bar assembly according to an embodiment of the present invention.

[0056] 2, 6, and 7, the center bus bar assembly 400 according to this embodiment may include a plurality of center bus bars 410 and spacers 420 positioned between the center bus bars 410 to occupy the spaces between the center bus bars 410.

[0057] The battery cell stack 120 according to this embodiment may include a plurality of the above-described double cells 110dc, and therefore a plurality of center bus bars 410 may also be disposed. In this case, considering the thickness of the battery cells 110, a space may be formed between adjacent center bus bars 410. If this space is left as is, it will impair the structural stability of the battery module 100. Therefore, in this embodiment, a spacer 420 is disposed between adjacent center bus bars 410 to stably support the center bus bars 410. A plurality of such spacers 420 may also be disposed. For ease of explanation, although only the center bus bar 410 and the spacer 420 are shown in FIGS. 6 and 7, in the battery module 100, the electrode leads 111 and 112 of the battery cells 110 included in the first battery cell stack 120a and the electrode leads 111 and 112 of the battery cells 110 included in the second battery cell stack 120b are already joined to the center bus bar 410. In other words, two battery cells 110 are connected through a center bus bar 410 to form a double cell 110dc, and a spacer 420 or a terminal spacer 520 described later may be disposed on one side of the center bus bar 410 to which the electrode leads 111 and 112 are joined.

[0058] The spacer 420 preferably includes an electrically insulating material, for example, a plastic injection molding. There is no particular limitation on the shape of the spacer 420, and the spacer 420 may be a member having a certain thickness so as to occupy the space between adjacent center bus bars 410.

[0059] The specific structures of the center bus bar and spacer according to this embodiment will be described in more detail below with reference to FIGS. 8 and 9. FIG.

[0060] Figures 8(a) and 8(b) are views showing the center bus bar and spacers included in the center bus bar assembly of Figure 7 from various angles. Figures 9(a) and 9(b) are views showing the spacers included in the center bus bar assembly of Figure 7 from various angles.

[0061] Referring to Figures 5 to 9, as described above, the center bus bar assembly 400 may include a plurality of center bus bars 410 and a plurality of spacers 420, and the center bus bars 410 and the spacers 420 to which the electrode leads 111, 112 are joined may be alternately arranged along the stacking direction of the battery cells 110.

[0062] The center bus bar 410 is a member for connecting the electrode leads 111, 112 and preferably includes a conductive material such as a metal material. The center bus bar 410 may include a first portion 411 connected to the electrode leads 111, 112 of the battery cells 110 and a second portion 412 extending from the first portion 411 and connected to the circuit unit. The first portion 411 may be plate-shaped for connection and bonding to the electrode leads 111, 112. The second portion 412 may extend from a lower portion of the first portion 411 and may be bent so that one surface of the second portion 412 is perpendicular to one surface of the first portion 411. The connection between the second portion 412 and the circuit unit will be described again below.

[0063] As described above, the spacer 420 may be a member having a certain thickness so as to fill the space between the center bus bars 410, and such a spacer 420 may have a protrusion 420P formed on one side thereof, and a coupling hole 420CH formed on the other side thereof, which is disposed opposite to the one side thereof, of the spacer 420. The protrusion 420P formed on the one side of the spacer 420 can be seen in Figure 9(a), and the coupling hole 420CH formed on the other side of the spacer 420 can be seen in Figure 9(b).

[0064] At least one through hole 410H may be formed in the center bus bar 410. The protrusion 420P of any one spacer 420, the through hole 410H of the center bus bar 410, and the coupling hole 420CH of the adjacent spacer 420 may be formed at positions corresponding to each other.

[0065] The protrusion 420P of any one spacer 420 may pass through the through hole 410H of the center bus bar 410 and then be inserted into the coupling hole 420CH of another spacer 420. In this manner, a plurality of spacers 420 may be coupled to one another by inserting the protrusions 420P into the coupling holes 420CH. At the same time, the protrusions 420P pass through the through hole 410H of the center bus bar 410, so that the center bus bar 410 can be fixed to the spacers 420 between the spacers 420. As the center bus bar 410 and the spacers 420 are alternately arranged, the center bus bar 410 and the spacers 420 can be firmly fixed to one another through the assembly of the protrusions 420P, the through hole 410H, and the coupling hole 420CH.

[0066] In addition, according to this embodiment, a plurality of spacers 420 may be arranged, and the spacers 420 may be assembled together by hook engagement. Specifically, the spacer 420 may include at least one first hook 420H1 protruding in one direction, and the spacer 420 may be formed with a hook groove 420G to which the first hook 420H1 is hook-engaged. For example, a first hook 420H1 protruding in the direction of other spacers 420 may be formed on each of the top and bottom surfaces of the spacer 420. Correspondingly, recessed hook grooves 420G may be formed on the top and bottom surfaces of the spacer 420. Although only the hook groove 420G formed on the top surface of the spacer 420 is shown in FIGS. 8(a) and 9(a) and 9(b), a similar recessed hook groove may also be formed on the bottom surface of the spacer 420. The spacers 420 may be assembled together by fastening the first hook 420H1 of one spacer 420 to the hook groove 420G of an adjacent spacer 420. That is, in the case of the center bus bar assembly 400 according to this embodiment, by arranging a plurality of spacers 420, the spacers 420 can be firmly assembled through engagement between the first hook 420H1 and the hook groove 420G, and the center bus bar 410 disposed between the first hook 420H1 and the hook groove 420G can also be stably fixed.

[0067] The structure of the terminal bus bar assembly according to this embodiment will be described in detail below with reference to FIGS. 10 and 11. FIG.

[0068] Figures 10(a) and 10(b) are exploded perspective views showing the terminal bus bar assembly of Figure 6. Specifically, Figures 10(a) and 10(b) show exploded views of two terminal bus bar assemblies 500 shown in Figure 6. Figure 11 is an exploded perspective view illustrating a connection form between a terminal bus bar assembly and one of the battery cells according to an embodiment of the present invention.

[0069] 2, 6, 10, and 11, the battery module 100 according to this embodiment may further include a pair of terminal bus bar assemblies 500 disposed at both ends of the center bus bar assembly 400 between the first battery cell stack 120a and the second battery cell stack 120b. One of the pair of terminal bus bar assemblies 500 is shown in FIG. 10(a), and the other is shown in FIG. 10(b).

[0070] The terminal bus bar assembly 500 may include a terminal bus bar 510, which may include a first portion 511 connected to the electrode leads 111, 112 of the battery cells 110 and a second portion 512 extending from the first portion 511 and exposed to the outside. Here, the term "outside" refers to the outside of the battery module 100. The terminal bus bar 510 preferably includes a conductive material such as a metal material.

[0071] The first portion 511 may be plate-shaped for connection and bonding with the electrode leads 111 and 112. The second portion 512 may extend from an upper portion of the first portion 511, or may be bent so that one surface of the second portion 512 is perpendicular to one surface of the first portion 511. Compared to the center bus bar 410 described above, the first portion 511 of the terminal bus bar 510 and the first portion 411 of the center bus bar 410 are similar to each other, but differ in that the second portion 512 of the terminal bus bar 510 is provided on the upper portion of the first portion 511, whereas the second portion 412 of the center bus bar 410 is provided on the lower portion of the first portion 411.

[0072] There is no particular limitation on the method of electrically connecting the electrode leads 111, 112 and the first portion 511 of the terminal bus bar 510, and welding may be used as an example.

[0073] The second portion 512 of the terminal bus bar 510 is a portion exposed to the outside of the battery module 100 and functions as an input / output terminal of the battery module 100 for an HV (High Voltage) connection. HV connection refers to an electrical connection that requires a relatively high voltage, such as the input / output terminals of a battery module. The battery module 100 according to this embodiment may be connected to another battery module or a battery disconnection unit (BDU) that controls the electrical connection of the battery modules through the second portion 512 of the terminal bus bar 510. In this embodiment, the terminal bus bar 510, which functions as an input / output terminal of the battery module 100, may be located between the first battery cell stack 120a and the second battery cell stack 120b.

[0074] The electrode leads 111, 112 of the battery cells 110 arranged at the outermost position in one direction of the first battery cell stack 120a may be connected to the first portion 511 of the terminal bus bar 510 included in one of the terminal bus bar assemblies 500, and the electrode leads 111, 112 of the battery cells 110 arranged at the outermost position in the other direction of the second battery cell stack 120b may be connected to the first portion 511 of the terminal bus bar 510 included in the other of the terminal bus bar assemblies 500. As an example, FIG. 11 shows a state in which the negative electrode lead 112 of the battery cell 110 arranged at the outermost position in one direction of the first battery cell stack 120a is connected to the first portion 511 of the terminal bus bar 510 included in one of the terminal bus bar assemblies 500. The terminal bus bar 510 in FIG. 11 functions as a negative terminal of the battery module 100. In this case, the one direction and the other direction correspond to mutually opposite directions in which the battery cells 110 are stacked. The electrical connection paths between the battery cells 110 and between the battery cells 110 and the terminal bus bar assembly will be described later with reference to FIG.

[0075] Meanwhile, the terminal busbar assembly 500 may further include a terminal spacer 520 that faces one side of the first portion 511 of the terminal busbar 510, and a terminal insulating plate 540 that covers the other side of the first portion 511 of the terminal busbar 510. The one side and the other side of the first portion 511 may be opposite sides to each other; in other words, the first portion 511 of the terminal busbar 510 may be located between the terminal spacer 520 and the terminal insulating plate 540.

[0076] The center bus bar 410 described above may be located on one side of the terminal spacer 520. Although not shown for ease of explanation, the electrode leads 111, 112 of the battery cell 110 are joined to this center bus bar 410. That is, as shown in FIG. 6 , each of the two center bus bars 410 located on the outermost sides of the plurality of center bus bars 410 may be located between the terminal spacer 520 and the spacers 420. Meanwhile, as shown in FIG. 7 , the remaining center bus bars 410, excluding the two center bus bars 410 located on the outermost sides, may be located between the spacers 420.

[0077] The terminal spacer 520 may occupy the space between the terminal busbar 510 and the center busbar 410, similar to the spacer 420. The terminal busbar 510 and the center busbar 410 may be tightly attached to the terminal spacer 520. The terminal spacer 520 preferably includes an electrically insulating material, for example, a plastic injection molding. There is no particular limitation on the shape of the terminal spacer 520, and the terminal spacer 520 may be a member having a certain thickness so as to occupy the space between the terminal busbar 510 and the center busbar 410. The terminal spacer 520 may be formed with a receiving portion 520S on which the second portion 512 of the terminal busbar 510 is placed. The receiving portion 520S is a portion that supports the second portion 512 of the terminal busbar 510, and may have a space therein for a nut to be placed. When the second portion 512 of the terminal busbar 510 is connected to an external conductor, a bolt and nut connection may be used.

[0078] A first protrusion 520P1 may be formed on one side of the terminal spacer 520, and a second protrusion 520P2 may be formed on the other side of the terminal spacer 520. The one side and the other side of the terminal spacer 520 may be opposite sides, and the one side of the terminal spacer 520 may be a side facing the terminal bus bar 510, and the other side of the terminal spacer 520 may be a side facing the center bus bar 410. Second protrusion 520P2 formed on the other side of the terminal spacer 520 can be seen in Figure 10 (a), and first protrusion 520P1 formed on the one side of the terminal spacer 520 can be seen in Figure 10 (b).

[0079] As described above, at least one through hole 410H may be formed in the center bus bar 410, and the through hole 410H of the center bus bar 410 and the second protrusion portion 520P2 of the terminal spacer 520 may be formed at positions corresponding to each other.

[0080] The second protrusion 520P2 of the terminal spacer 520 may pass through the through hole 410H of the center bus bar 410 arranged outermost among the center bus bars 410 and then be inserted into the coupling hole 420CH (see FIG. 9(b)) of the spacer 420 arranged outermost among the spacers 420. In this manner, the terminal spacer 520 can be coupled to the adjacent spacer 420 by inserting the second protrusion 520P2 into the coupling hole 420CH. At the same time, because the second protrusion 520P2 passes through the through hole 410H of the center bus bar 410 arranged outermost, the outermost center bus bar 410 can be fixed between the terminal spacer 520 and the spacer 420.

[0081] Meanwhile, through hole 510H may be formed in first portion 511 of terminal bus bar 510, and through hole 540H may be formed in terminal insulating plate 540. Through hole 510H of terminal bus bar 510, through hole 540H of terminal insulating plate 540, and first protrusion 520P1 of terminal spacer 520 may be formed at positions corresponding to each other.

[0082] The first protrusion 520P1 of the terminal spacer 520 may pass through the through hole 510H of the terminal bus bar 510 and then be inserted into the through hole 540H of the terminal insulating plate 540. In this manner, the terminal insulating plate 540 can be coupled to the terminal spacer 520 by inserting the first protrusion 520P1 into the through hole 540H of the terminal insulating plate 540. At the same time, because the first protrusion 520P1 passes through the through hole 510H of the terminal bus bar 510, the terminal bus bar 510 can be fixed between the terminal spacer 520 and the terminal insulating plate 540.

[0083] In particular, the first protrusion 520P1 may have a thick portion at its tip, and the first protrusion 520P1 may be tightly fitted into the through-hole 540H of the terminal insulating plate 540. After the tight fit, the thick portion can prevent the terminal insulating plate 540 from coming off.

[0084] Meanwhile, although not specifically shown, the terminal spacer 520 may be provided with a hook groove to which the first hook 420H1 (see FIG. 8 or 9) of the adjacent spacer 420 is coupled.

[0085] In summary, the pair of terminal bus bar assemblies 500 arranged at both ends of the center bus bar assembly 400 can be assembled using the first protrusion 520P1 to improve the assembly between the internal components, and can be fixed to the center bus bar assembly 400 using the second protrusion 520P2.

[0086] Terminal insulating plate 540 may be a plate-shaped member made of an electrically insulating material. Such terminal insulating plate 540 covers the other side of first portion 511 of terminal bus bar 510, thereby preventing first portion 511 of terminal bus bar 510 from being exposed to the outside and causing a short circuit.

[0087] Meanwhile, the terminal bus bar assembly 500 may further include a connecting bus bar 530 connected to the first portion 511 of the terminal bus bar 510. The connecting bus bar 530 preferably includes a conductive material such as a metal material. The connecting bus bar 530 may be connected to a lower portion of the first portion 511 of the terminal bus bar 510, and may include a portion that is bent so as to be perpendicular to one surface of the first portion 511 of the terminal bus bar 510. The connecting bus bar 530 may perform a function similar to that of the second portion 412 of the center bus bar 410 described above, which will be described again below.

[0088] The advantages of the battery module according to this embodiment will be described below in comparison with a battery module according to a comparative example of the present invention.

[0089] FIG. 12 is an exploded perspective view showing a battery module according to a comparative example of the present invention.

[0090] 12 , a battery module 10 according to a comparative example of the present invention includes a battery cell stack 12 in which a plurality of battery cells 11 are stacked, first and second side plates 21 and 22 arranged on both sides of the battery cell stack 12, and connecting members 60 arranged on the top and bottom of the battery cell stack 120 and connecting the first and second side plates 21 and 22. In the battery module 10, the battery cells 11 may be stacked in one direction in the battery cell stack 12, and electrode leads may protrude in a direction perpendicular to the stacking direction of the battery cells 11. A first bus bar frame 71 and a second bus bar frame 72 may be arranged in the direction in which the electrode leads protrude. A bus bar is attached to each of the first bus bar frame 71 and the second bus bar frame 72, and the bus bars can connect the electrode leads of the battery cells 11.

[0091] The battery module 10 may also include a first insulating plate 31 that covers the first bus bar frame 71 and a second insulating plate 32 that covers the second bus bar frame 72 .

[0092] As shown in FIG. 12, the battery module 10 according to this comparative example corresponds to a single-model battery module having one battery cell stack 12, and as shown in FIG. 2, the battery module 100 according to this embodiment corresponds to a twin-model battery module having a first battery cell stack 120a and a second battery cell stack 120b arranged along the length direction of the battery cell 110.

[0093] To achieve the same battery capacity, two battery modules 10 according to the comparative example must be compared with one battery module 100 according to the present embodiment. When two battery modules 10 are arranged longitudinally, two bus bar frames 71, 72 and two insulating plates 31, 32 are located between the battery cell stack 12 of the front battery module 10 and the battery cell stack 12 of the rear battery module 10. To put it another way, the second bus bar frame 72 and second insulating plate 32 of the front battery module 10 and the first insulating plate 31 and first bus bar frame 71 of the rear battery module 10 are located between the battery cell stack 12 of the front battery module 10 and the battery cell stack 12 of the rear battery module 10. In other words, since two bus bar frames 71, 72 and two insulating plates 31, 32 are located between the two battery cell stacks 12, the space occupied in the longitudinal direction of the battery cells 11 increases and the number of components increases.

[0094] In contrast, in the battery module 100 according to this embodiment, only the center bus bar assembly 400 and the terminal bus bar assembly 500 are disposed between the first battery cell stack 120a and the second battery cell stack 120b. Since the terminal bus bar assemblies 500 are positioned at both ends of the center bus bar assembly 400, no additional space is required in the longitudinal direction of the battery cells 110. Furthermore, in the center bus bar assembly 400, only a space equivalent to the thickness of the center bus bar 410 or the spacer 420 is required in the longitudinal direction of the battery cells 110.

[0095] In other words, if two battery modules 10 according to this comparative example were to be arranged to achieve the same capacity, additional components would be required, increasing the required space in the longitudinal direction and resulting in disadvantages in terms of energy density and space utilization. In contrast, in the case of the battery module 100 according to this embodiment, by providing the center bus bar assembly 400, the required space in the longitudinal direction can be significantly reduced compared to a single-model battery module 10, even when the first battery cell stack 120a and the second battery cell stack 120b are electrically connected. In other words, the battery module 100 according to this embodiment has the advantages of being able to reduce the number of components and improving energy density and space utilization by reducing the required space.

[0096] Furthermore, since each of the two battery modules 10 is provided with a terminal bus bar, the HV connection configuration for each battery pack may be somewhat complicated. In contrast, the battery module 100 according to this embodiment requires only a pair of terminal bus bars 510 even though it includes first and second battery cell stacks 120a, 120b, which simplifies the HV connection configuration for each battery pack and reduces the number of components.

[0097] Hereinafter, a low voltage (LV) connection configuration of the battery module 100 according to this embodiment will be described in detail. The LV connection refers to an electrical connection that requires a relatively low voltage, such as a battery electrical component. As an example, the battery module 100 may be provided with a module connector (not shown) for sensing the voltage and temperature of the battery cells 110 included in the battery module 100. The module connector is connected to a battery management system (BMS) disposed outside the battery module 100 and transmits measured voltage and temperature data to the BMS. The BMS is responsible for managing the voltage and temperature of the battery module 100 based on the transmitted voltage and temperature data.

[0098] FIG. 13 is a perspective view showing a first external bus bar frame, a second external bus bar frame, a first circuit unit, and a second circuit unit according to one embodiment of the present invention.

[0099] Referring to Figures 2 and 13, the battery module 100 of this embodiment may further include a first external busbar frame 710 located on one side of the first battery cell stack 120a and a second external busbar frame 720 located on one side of the second battery cell stack 120b.

[0100] The first external busbar frame 710 may be positioned in the opposite direction to the center busbar assembly 400 relative to the first battery cell stack 120a, and the second external busbar frame 720 may be positioned in the opposite direction to the center busbar assembly 400 relative to the second battery cell stack 120b. That is, the first external busbar frame 710, the first battery cell stack 120a, the center busbar assembly 400, the second battery cell stack 120b, and the second external busbar frame 720 may be positioned in this order along the length direction of the battery cells 110 (direction parallel to the y-axis). Both the first external busbar frame 710 and the second external busbar frame 720 preferably include an electrically insulating material, and may include a plastic injection molding, for example.

[0101] The first external bus bar frame and the second external bus bar frame will be described in detail with reference to FIGS. 14 and 15.

[0102] Fig. 14 is a front view of the first external bus bar frame of Fig. 13 as seen from direction "B". Fig. 15 is a rear view of the second external bus bar frame of Fig. 13 as seen from direction "C".

[0103] 2, 13, and 14, the electrode leads 111, 112 protruding from the battery cells 110 included in the first battery cell stack 120a toward the first external busbar frame 710 may be connected to a first external busbar 711 attached to the first external busbar frame 710. Specifically, the first external busbar 711 may be attached to a surface of the first external busbar frame 710 opposite to a surface facing the first battery cell stack 120a. Slits 710S may be formed in the first external busbar frame 710, and the electrode leads 111, 112 may pass through the slits 710S and be bent to be connected to the first external busbar 711. There are no particular limitations on the method of connection between the electrode leads 111, 112 and the first external busbar 711, but welding may be used to enable electrical and physical connection.

[0104] A first sensing unit 712 for voltage sensing may be attached to the first external bus bar frame 710. Specifically, the first sensing unit 712 may be attached to a surface of the first external bus bar frame 710 opposite to the surface facing the first battery cell stack 120a. The first sensing unit 712 may be a flexible printed circuit board (FPCB) or a flexible flat cable (FFC). The first sensing unit 712 may be connected to the first external bus bar 711 through a first bonding plate 713 provided at one end thereof. A welding method may be used to connect the first bonding plate 713 and the first external bus bar 711.

[0105] The first sensing unit 712 is connected to the battery cells 110 of the first battery cell stack 120a via the first bonding plate 713 and the first external bus bar 711, and can measure voltage information of the battery cells 110 during charging and discharging. Although not specifically shown, the first sensing unit 712 is connected to the module connector described above and can transmit voltage information to the module connector. The voltage information can be transmitted to a battery management system (BMS) located outside the battery module 100 via the module connector.

[0106] 2, 13, and 15, the electrode leads 111, 112 protruding from the battery cells 110 included in the second battery cell stack 120b toward the second external busbar frame 720 may be connected to a second external busbar 721 attached to the second external busbar frame 720. Specifically, the second external busbar 721 may be attached to the surface of the second external busbar frame 720 opposite the surface facing the second battery cell stack 120b. Slits 720S may be formed in the second external busbar frame 720, and the electrode leads 111, 112 may pass through the slits 720S and be bent to be connected to the second external busbar 721. There are no particular limitations on the method of connection between the electrode leads 111, 112 and the second external busbar 721, but welding may be used to enable electrical and physical connection.

[0107] A second sensing unit 722 for voltage sensing may be attached to the second external bus bar frame 720. Specifically, the second sensing unit 722 may be attached to a surface of the second external bus bar frame 720 opposite to the surface facing the second battery cell stack 120b. The second sensing unit 722 may be a flexible printed circuit board (FPCB) or a flexible flat cable (FFC). The second sensing unit 722 may be connected to the second external bus bar 721 through a second bonding plate 723 provided at one end thereof. A welding method may be used to connect the second bonding plate 723 and the second external bus bar 721.

[0108] The second sensing unit 722 is connected to the battery cells 110 of the second battery cell stack 120b via the second bonding plate 723 and the second external bus bar 721 and can measure voltage information of the battery cells 110 during charging and discharging. Although not specifically shown, the second sensing unit 722 is connected to the module connector and can transmit voltage information to the module connector. The voltage information can be transmitted to a battery management system (BMS) located outside the battery module 100 via the module connector.

[0109] 13 to 15, the battery module 100 according to this embodiment may further include circuit units 810 and 820. Specifically, the first circuit unit 810 is a member that extends along the side surfaces of the first and second battery cell stacks 120a and 120b (see FIG. 2) and connects the first sensing unit 712 and the second sensing unit 722, and may be a flexible printed circuit board (FPCB) or a flexible flat cable (FFC). The second circuit unit 820 is a member that connects at least one of the first sensing unit 712 or the second sensing unit 722 to the center bus bar 410, and may also be a flexible printed circuit board (FPCB) or a flexible flat cable (FFC). FIG. 13 shows how second circuit unit 820 connects second sensing unit 722 and center bus bar 410.

[0110] As described above, the center bus bar 410 may include a first portion 411 connected to the electrode leads 111, 112 of the battery cells 110 and a second portion 412 extending from the first portion 411 and connected to the circuit unit, and one side of the second portion 412 may be bent so as to be perpendicular to one side of the first portion 411. For ease of explanation, FIG. 13 shows only some center bus bars 410 among the components of the center bus bar assembly, and only terminal bus bars 510 among the components of the terminal bus bar assembly. The second circuit unit 820 may extend to the lower end of the center bus bar assembly and be connected to the second portion 412 of the center bus bar 410, or may be connected to the connecting bus bar 530 connected to the terminal bus bar 510. FIG. 15 shows the second circuit unit 820 connected to the second sensing unit 722.

[0111] The second portion 412 of the center bus bar 410 and the connecting bus bar 530 connected to the first portion 511 of the terminal bus bar 510 perform similar functions. The electrode leads 111, 112 of the battery cells 110 included in the first and second battery cell stacks 120a, 120b can be connected to the second circuit unit 820 through the second portion 412 of the center bus bar 410 or the connecting bus bar 530, and voltage information can be transmitted to the second sensing unit 722 through the second circuit unit 820. As described above, the second sensing unit 722 is connected to the module connector and can transmit voltage information to the module connector, and the voltage information can be transmitted to a battery management system (BMS) located outside the battery module 100 through the module connector.

[0112] Fig. 16 is a schematic diagram illustrating an HV connection mode and an LV connection mode in a battery module according to an embodiment of the present invention. In particular, Fig. 16 is a schematic diagram illustrating a plan view of the battery module 100 as viewed along the -z axis direction on the xy plane.

[0113] 2 and 16, a pair of terminal busbar assemblies 500 are positioned between the first battery cell stack 120a and the second battery cell stack 120b. One of the pair of terminal busbar assemblies 500 may include a terminal busbar that functions as a positive terminal, and the other of the pair of terminal busbar assemblies 500 may include a terminal busbar that functions as a negative terminal. The positive leads 111 of the battery cells 110 may be connected in series to the negative leads of the other battery cells 110 from one terminal busbar assembly 500 to the other terminal busbar assembly 500. In particular, the double cell 110dc structure described above is formed by connecting the battery cells 110 of the first battery cell stack 120a to the battery cells 110 of the second battery cell stack 120b. FIG. 16 shows that five double cells 110dc have been formed. In addition, the battery cells 110 arranged on the outermost side in one direction of the first battery cell stack 120a and connected to the terminal bus bar assembly 500 and the battery cells 110 arranged on the outermost side in the second battery cell stack 120b and connected to the other terminal bus bar assembly 500 are not shown to form a double cell structure. In other words, the battery cells 110 of the first battery cell stack 120a and the battery cells 110 of the second battery cell stack 120b are connected in series through the center bus bar assembly within the battery module 100, and ultimately, all of the battery cells 110 can be connected in series.

[0114] Meanwhile, as described above, the first circuit unit 810 may continue along the sides of the first and second battery cell stacks 120a, 120b and connect the first sensing unit 712 on the first external bus bar frame 710 to the second sensing unit 722 on the second external bus bar frame 720. Also, as described above, the second circuit unit 820 may connect at least one of the first sensing unit 712 or the second sensing unit 722 to the center bus bar 410 (see FIG. 13 ).

[0115] The upper insulating member and the lower insulating member according to this embodiment will be described in detail below with reference to FIGS. 17 to 21. FIG.

[0116] 17 is a perspective view showing a center bus bar assembly, an upper insulating member, and a lower insulating member according to an embodiment of the present invention. Although not shown in FIG. 2, referring to FIG. 17, the battery module 100 according to this embodiment may further include an upper insulating member 910 positioned above the center bus bar assembly 400 and including an electrically insulating material, and a lower insulating member 920 positioned below the center bus bar assembly 400 and including an electrically insulating material. The upper insulating member 910 and the lower insulating member 920 cover the upper and lower regions of the center bus bar assembly 400, respectively, thereby preventing the center bus bar assembly 400 and the electrode leads 111 and 112 from being exposed to the outside and causing a short circuit.

[0117] Figures 18(a), (b), and (c) are views showing the upper insulating member in Figure 17 from various angles. Specifically, Figure 18(a) is a perspective view of the upper insulating member 910, Figure 18(b) is a view of the upper insulating member 910 viewed along the -z axis direction on the xy plane, and Figure 18(c) is a side view of the upper insulating member 910 viewed along the -y axis direction on the xz plane.

[0118] 2, 17, and 18, the upper insulating member 910 may include a first wall portion 911 facing the first battery cell stack 120a, a second wall portion 912 facing the second battery cell stack 120b, and a bottom portion 913 connecting the first wall portion 911 and the second wall portion 912 and facing the center bus bar assembly 400.

[0119] 18(b), when the upper insulating member 910 is viewed from the side, the first wall portion 911, the second wall portion 912, and the bottom portion 913 may have a U-shape. Although the height of the center bus bar assembly 400 may be lower than the height of the first battery cell stack 120a and the height of the second battery cell stack 120b, such a U-shape is appropriate for covering the upper region of the center bus bar assembly 400 between the first battery cell stack 120a and the second battery cell stack 120b.

[0120] 10(a) and (b), a fastening hole 910H1 and a terminal hole 910H2 may be formed in the bottom 913 of the upper insulating member 910. First, the terminal hole 910H2 may be formed in a position corresponding to the second portion 512 of the terminal bus bar 510. In other words, the second portion 512 of the terminal bus bar 510 is exposed to the outside through the terminal hole 910H2 and functions as an input / output terminal of the battery module 100.

[0121] Meanwhile, FIG. 19 is a partial view illustrating a coupling form between the fastening hole of the upper insulating member and the second hook of the spacer.

[0122] 7, 8, 9, 18(b), and 19, the spacer 420 and the upper insulating member 910 according to this embodiment may be assembled by engaging a hook. That is, the spacer 420 and the upper insulating member 910 may be assembled by a mechanical fastening method.

[0123] As an example, at least one of the spacers 420 according to this embodiment may be formed with a second hook 420H2 that protrudes toward the upper insulating member 910. Figures 8(a) and 8(b) show a spacer 420 on which the second hook 420H2 is formed, and Figures 9(a) and 9(b) show a spacer 420 on which the second hook is not formed.

[0124] A fastening hole 910H1 may be formed in a portion of the bottom 913 of the upper insulating member 910 corresponding to the second hook 420H2, and the second hook 420H2 protruding toward the upper insulating member 910 may be fastened to this fastening hole 910H1.

[0125] 20 is a perspective view showing the lower insulating member of FIG.

[0126] 17 and 20, the spacer 420 and the lower insulating member 920 according to this embodiment may be assembled by engaging a hook, that is, the spacer 420 and the lower insulating member 920 may be assembled by a mechanical fastening method.

[0127] For example, the lower insulating member 920 may be a plate-shaped member and may include hook members 920H protruding upward. As shown in Fig. 17, a locking step may be formed in a portion of the spacer 420 corresponding to the hook members 920H, and the hook members 920H may be fastened to the locking step.

[0128] In summary, the upper insulating member 910 and the lower insulating member 920 according to this embodiment can be fixed to the center bus bar assembly 400 by a mechanical fastening method such as hook engagement while being disposed on the upper and lower parts of the center bus bar assembly 400. Therefore, compared to using a separate assembly method using bolts and nuts, this has the advantage of making it relatively easy to assemble the upper insulating member 910, the lower insulating member 920, and the center bus bar assembly 400.

[0129] FIG. 21 is an enlarged partial view of part "A" in FIG.

[0130] 1, 20, and 21, the battery module 100 according to this embodiment may include first and second side plates 210 and 220, which will be described later. In this case, some of the hook members 920H formed on the lower insulating member 920 may be fastened to the first and second side plates 210 and 220. That is, in order to improve the ease of assembly of the battery module, hook engagement may also be applied between the first and second side plates 210 and 220 and the lower insulating member 920.

[0131] Meanwhile, referring again to Figures 1 and 2, the battery module 100 according to this embodiment may include first and second side plates 210, 220 arranged on both sides of the battery cell stack 120, and connecting members 600 arranged on the top and bottom of the battery cell stack 120 and connecting the first and second side plates 210, 220.

[0132] The first side plate 210 and the second side plate 220 may be located on both sides of the battery cell stack 120 to support the battery cell stack 120. More specifically, the first side plate 210 and the second side plate 220 may be located on both sides in the direction in which the plurality of battery cells 110 are stacked, i.e., in the direction parallel to the y-axis in FIG. 2. The first side plate 210 may cover both one side of the first battery cell stack 120a and one side of the second battery cell stack 120b, and the second side plate 220 may cover both the other side of the first battery cell stack 120a and the other side of the second battery cell stack 120b.

[0133] Meanwhile, the connecting member 600 connecting the first side plate 210 and the second side plate 220 may be a metal band-type member. More specifically, the connecting member 600 may be a band-type member including an elastic metal material.

[0134] A single or multiple connecting members 600 may be provided on at least one of the upper and lower sides of the battery cell stack 120. As an example, a plurality of connecting members 600 may be provided on at least one of the upper and lower sides of the battery cell stack 120. FIG. 2 shows that a plurality of connecting members 600 are provided on both the upper and lower sides of the battery cell stack 120. Such connecting members 600 may be spaced apart from each other at regular intervals and located on both the upper and lower sides of the battery cell stack 120. As an example, FIG. 2 shows that six connecting members 600 are arranged on each of the upper and lower sides of the battery cell stack 120.

[0135] As described above, the connecting member 600 is a member that connects the first side plate 210 and the second side plate 220, and therefore may have a configuration that continues in the direction from the first side plate 210 to the second side plate 220, that is, along the stacking direction of the battery cells 110. In other words, the connecting member 600 may extend in a direction parallel to the y-axis direction, with one end connected to the first side plate 210 and the other end connected to the second side plate 220. Such a connecting member 600 may be fixed to the first side plate 210 and the second side plate 220 by welding.

[0136] Meanwhile, the battery module 100 according to this embodiment may further include a first outer insulating plate 310 covering the first outer bus bar frame 710 and a second outer insulating plate 320 covering the second outer bus bar frame 720 .

[0137] The first external insulating plate 310 and the second external insulating plate 320 preferably include an electrically insulating material. The first external insulating plate 310 and the second external insulating plate 320 are arranged to prevent the electrical components attached to the first external bus bar frame 710 and the second external bus bar frame 720 from being exposed to the outside and causing a short circuit. The first external insulating plate 310 and the second external insulating plate 320 may be connected to the first side plate 210 and the second side plate 220 by fastening with bolts and nuts.

[0138] FIG. 22 is an enlarged partial view showing how a battery module is fixed to a mounting beam according to an embodiment of the present invention.

[0139] 2 and 22, the battery module 100 according to this embodiment may be attached to a pack tray and secured to adjacent mounting beams 1200. Specifically, when the battery module 100 is attached to the pack tray, the mounting beams 1200 may be located on both sides of the battery module 100.

[0140] According to this embodiment, the first side plate 210 and the second side plate 220 may each include a support portion 200S that supports the outermost battery cell of the battery cell stack 120, and a fixing portion 200F that protrudes perpendicular to one surface of the support portion 200S. Both the first side plate 210 and the second side plate 220 may have the fixing portion 200F formed on the surface opposite to the surface on which the battery cell stack is arranged. Fixing holes 200FH for mounting and fixing may be formed in the fixing portion 200F. There is no particular limit to the number of fixing portions 200F, and one or more fixing portions 200F may be provided.

[0141] To protect against external vibrations and shocks, a mounting fixation is required to fix the battery module 100 to the pack tray. The first side plate 210 and the second side plate 220 of the battery module 100 according to this embodiment can be fixed to a mounting beam 1200 disposed on the pack tray. The mounting beam 1200, which has a shape extending in one direction, fixes the battery module 100 and can buffer shocks, etc., transmitted to the battery module 100 from external shocks, etc.

[0142] In terms of height, the fixing part 200F may be located higher than the mounting beam 1200. The fixing part 200F may be fixed to the upper surface of the mounting beam 1200, and a bolt-type connection may be made as shown in Fig. 21. That is, a mounting hole 1200H having an internally threaded thread may be formed on the upper surface of the mounting beam 1200, and a bolt-shaped fastening member 1300 may be inserted into and fastened to the mounting hole 1200H after passing through the fixing hole 200FH of the fixing part 200F.

[0143] During repeated charging and discharging, the internal electrolyte of the battery cell 110 may decompose, generating gas and causing the battery cell 110 to swell, i.e., swelling may occur. If the swelling of the battery cell 110 cannot be controlled, it may cause structural deformation of the battery module 100 in which multiple battery cells 110 are stacked, and may also adversely affect the durability and performance of the battery module 100.

[0144] In particular, pure silicon cells, solid-state batteries, and high-SiO2 cells are currently used as battery cells to manufacture high-capacity battery modules and battery packs. These cells tend to swell to a greater extent. Therefore, effectively controlling swelling of the battery cells 110 inside the battery module or pack is essential for manufacturing high-capacity battery modules and packs. Referring again to FIG. 2, because pouch-type battery cells 110 typically swell more in the thickness direction, the structures directly related to swelling control are the first side plate 210 and the second side plate 220 located on both sides of the battery cell stack 120.

[0145] In this case, the first side plate 210 and the second side plate 220 are directly coupled and fixed to the mounting beam 1200 on the pack tray, and the mounting beam 1200 is designed to support the first side plate 210 and the second side plate 220 from the sides and control swelling. In other words, the mounting is performed through the first side plate 210 and the second side plate 220, and at the same time, the mounting beam 1200 complements the rigidity and durability of the battery module 100 for swelling control.

[0146] 2 is an exemplary structure in which the battery cell stack 120 is disposed in an internal space formed by the first and second side plates 210, 220, the first and second outer insulating plates 310, 320, and the connecting member 600. Although not specifically shown, a battery module in which the battery cell stack 120 is housed in a housing having an internal space and then end plates are joined to the housing to seal the housing is also possible.

[0147] The process of manufacturing the battery module according to this embodiment will be described below with reference to FIGS.

[0148] 23(a) and 23(b) are partial views showing the connection between the battery cells and the center bus bar and the connection between the battery cells and the terminal bus bars, respectively.

[0149] 23(a), the electrode leads 111, 112 of two battery cells 110 are connected via a center bus bar 410 to form a double cell 110dc structure. The negative electrode lead 112 of any one of the battery cells 110 and the positive electrode lead 111 of any one of the battery cells 110 may be welded to the center bus bar 410. A plurality of such double cell 110dc structures are formed in advance.

[0150] 23(b), the electrode lead 111 of one battery cell 110 is welded to the first portion 511 of the terminal bus bar 510. Two battery cells 110 are provided, each joined to the terminal bus bar 510. The second portions 512 of the two terminal bus bars 510 function as input / output terminals for HV connection of the battery module 100.

[0151] 24(a), (b), and (c) are partial views illustrating the process of assembling the terminal bus bar and the terminal spacer.

[0152] 24(a) to 24(c) as well as FIG. 23(b), a terminal insulating plate 540 may be disposed on the second side plate 220. Then, one battery cell 110 joined to the terminal bus bar 510 manufactured as shown in FIG. 23(b) may be disposed on one side of the terminal insulating plate 540 and the second side plate 220. In this case, the terminal bus bar 510 is placed on the terminal insulating plate 540, and the through hole 540H of the terminal insulating plate 540 and the through hole 510H of the terminal bus bar 510 are positioned to correspond to each other.

[0153] Next, terminal spacer 520 may be placed on the surface of terminal bus bar 510 opposite the surface facing terminal insulating plate 540. At this time, as described with reference to FIGS. 10 and 11 , first protrusion 520P1 of terminal spacer 520 may pass through through hole 510H of terminal bus bar 510 and then be inserted into through hole 540H of terminal insulating plate 540. Terminal bus bar 510 may be fixed between terminal spacer 520 and terminal insulating plate 540.

[0154] FIG. 25 is a partial view illustrating the process of stacking double cells.

[0155] Referring to Figure 25 together with Figure 24(c), one double cell 110dc may be arranged so that the center bus bar 410 to which the electrode leads 111 and 112 are joined is placed on the terminal spacer 520 in Figure 24(c).

[0156] Subsequently, one spacer 420 may be disposed on the center bus bar 410 to which the electrode leads 111 and 112 are bonded, and another double cell 110dc may be disposed on the spacer 420 so that the center bus bar 410 to which the electrode leads 111 and 112 are bonded is placed. In this manner, the spacers 420 and the double cells 110dc may be alternately disposed. In this case, as described with reference to FIGS. 7 to 9, the protrusion 420P of the spacer 420 may pass through the through hole 410H of the center bus bar 410 and then be inserted into the coupling hole 420CH of another spacer 420. Furthermore, the spacers 420 may be assembled by fastening the first hook 420H1 of one spacer 420 to the hook groove 420G of the adjacent spacer 420.

[0157] After the spacers 420 and the double cells 110dc are alternately arranged, a terminal spacer 520 is placed, and another one of the battery cells 110 joined to the terminal bus bar 510 may be placed on the terminal spacer 520. Finally, a terminal insulating plate 540 and a first side plate 210 may be placed. This finally results in a structure in which the first battery cell stack 120a, the second battery cell stack 120b, the center bus bar assembly 400, and the first and second side plates 210, 220 shown in FIG. 2 are assembled.

[0158] 2 and 13, a first external bus bar frame 710 may be disposed on one side of the first battery cell stack 120a, a second external bus bar frame 720 may be disposed on one side of the second battery cell stack 120b, and circuit units 810, 820 may be connected to each other. Next, referring to FIGS. 17 to 20, an upper insulating member 910 and a lower insulating member 920 may be assembled to the top and bottom of the center bus bar assembly 400, respectively. Finally, referring again to FIG. 2, the first side plate 210 and the second side plate 220 may be connected to each other with the connecting member 600, and the first external insulating plate 310 and the second external insulating plate 320 may be joined to the first side plate 210 and the second side plate 220 by fastening bolts and nuts.

[0159] The battery module 100 according to this embodiment can be manufactured using the above-described series of methods. Meanwhile, the first and second side plates 210, 220 and the connecting member 600 coupled thereto are only a form according to one embodiment of the battery module 100, and although not specifically shown, other forms such as a mono-frame, a combination structure of a U-shaped frame and an upper cover, a four-plate combined structure, etc. are all possible.

[0160] In this embodiment, terms indicating directions such as front, back, left, right, up, and down are used, but these terms are used only for convenience of explanation and may change depending on the position of the object of interest, the position of the observer, etc.

[0161] One or more battery modules according to the above-described embodiments may be installed together with various control and protection systems, such as a Battery Management System (BMS), a Battery Disconnect Unit (BDU), and a cooling system, to form a battery pack.

[0162] The battery module or battery pack can be applied to various devices, specifically, transportation means such as electric bicycles, electric cars, and hybrids, and energy storage systems (ESS), but is not limited thereto, and can be applied to various devices that can use secondary batteries.

[0163] Although the preferred embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements made by those skilled in the art using the basic concept of the present invention defined in the following claims also fall within the scope of the present invention. [Explanation of symbols]

[0164] 100: Battery module 110: Battery cell 110dc: double cell 120: Battery cell stack 120a: First battery cell stack 120b: Second battery cell stack 210: First side plate 220: Second side plate 310: First outer insulating plate 320: Second outer insulating plate 400: Center bus bar assembly 410: Center bus bar 420: Spacer 500: Terminal busbar assembly 510: Terminal bus bar 520: Terminal spacer 530: Connecting bus bar 540: Terminal insulating plate

Claims

1. a battery cell stack including a first battery cell stack and a second battery cell stack in which a plurality of battery cells are stacked; a center bus bar assembly disposed between the first battery cell stack and the second battery cell stack; A battery module comprising: the first battery cell stack and the second battery cell stack are arranged along a direction perpendicular to a direction in which the battery cells of the first battery cell stack or the second battery cell stack are stacked, any one battery cell included in the first battery cell stack and any one battery cell included in the second battery cell stack are electrically connected to each other through a center bus bar included in the center bus bar assembly, thereby forming a double cell structure; the battery cell stack includes at least one of the dual cell structures; The center bus bar is arranged in plurality, The center bus bar assembly further includes a spacer disposed between the center bus bars and occupying a space between the center bus bars to stably support the center bus bars.

2. the battery cell is a pouch cell and includes electrode leads protruding from one end and the other end of the battery cell, respectively; 2. The battery module of claim 1, wherein the electrode lead of any one battery cell included in the first battery cell stack and the electrode lead of any one battery cell included in the second battery cell stack are electrically connected via the center bus bar to form the double cell structure.

3. 3. The battery module of claim 2, wherein the electrode lead of any one battery cell included in the first battery cell stack and the electrode lead of any one battery cell included in the second battery cell stack are welded to the center bus bar.

4. A battery cell stack including a first battery cell stack and a second battery cell stack in which a plurality of battery cells are stacked; a center bus bar assembly disposed between the first battery cell stack and the second battery cell stack; A battery module comprising: the first battery cell stack and the second battery cell stack are arranged along a direction perpendicular to a direction in which the battery cells of the first battery cell stack or the second battery cell stack are stacked, any one battery cell included in the first battery cell stack and any one battery cell included in the second battery cell stack are electrically connected to each other through a center bus bar included in the center bus bar assembly, thereby forming a double cell structure; the battery cell stack includes at least one of the dual cell structures; The center bus bar is arranged in plurality, the center bus bar assembly further includes a spacer disposed between the center bus bars and occupying a space between the center bus bars; The spacer is arranged in plurality, A protrusion and a coupling hole are formed on one surface and the other surface of the spacer, respectively; a through hole is formed in the center bus bar; The battery module, wherein the protrusion of any one of the spacers passes through the through hole of the center bus bar and is then inserted into the coupling hole of another of the spacers.

5. A battery cell stack including a first battery cell stack and a second battery cell stack in which a plurality of battery cells are stacked; a center bus bar assembly disposed between the first battery cell stack and the second battery cell stack; A battery module comprising: the first battery cell stack and the second battery cell stack are arranged along a direction perpendicular to a direction in which the battery cells of the first battery cell stack or the second battery cell stack are stacked, any one battery cell included in the first battery cell stack and any one battery cell included in the second battery cell stack are electrically connected to each other through a center bus bar included in the center bus bar assembly, thereby forming a double cell structure; the battery cell stack includes at least one of the dual cell structures; The center bus bar is arranged in plurality, the center bus bar assembly further includes a spacer disposed between the center bus bars and occupying a space between the center bus bars; The spacer is arranged in plurality, The spacers are assembled together by engaging hooks in the battery module.

6. A battery cell stack including a first battery cell stack and a second battery cell stack in which a plurality of battery cells are stacked; a center bus bar assembly disposed between the first battery cell stack and the second battery cell stack; A battery module comprising: the first battery cell stack and the second battery cell stack are arranged along a direction perpendicular to a direction in which the battery cells of the first battery cell stack or the second battery cell stack are stacked, any one battery cell included in the first battery cell stack and any one battery cell included in the second battery cell stack are electrically connected to each other through a center bus bar included in the center bus bar assembly, thereby forming a double cell structure; the battery cell stack includes at least one of the dual cell structures; the battery pack further includes a pair of terminal bus bar assemblies disposed between the first battery cell stack and the second battery cell stack and at both ends of the center bus bar assembly, the terminal bus bar assembly includes a terminal bus bar; The terminal bus bar includes a first portion connected to an electrode lead of the battery cell, and a second portion extending from the first portion and exposed to the outside.

7. the electrode lead of the battery cell disposed at the outermost position in one direction of the first battery cell stack is connected to the first portion of the terminal bus bar included in one of the terminal bus bar assemblies; 7. The battery module of claim 6, wherein the electrode lead of the battery cell disposed on the outermost side in the other direction of the second battery cell stack is connected to the first portion of the terminal bus bar included in another one of the terminal bus bar assemblies.

8. 7. The battery module of claim 6, wherein the terminal bus bar assembly further includes a terminal spacer that faces one side of the first portion of the terminal bus bar, and a terminal insulating plate that covers the other side of the first portion of the terminal bus bar.

9. A battery cell stack including a first battery cell stack and a second battery cell stack, each of which has a plurality of battery cells stacked on top of one another; a center bus bar assembly disposed between the first battery cell stack and the second battery cell stack; A battery module comprising: the first battery cell stack and the second battery cell stack are arranged along a direction perpendicular to a direction in which the battery cells of the first battery cell stack or the second battery cell stack are stacked, any one battery cell included in the first battery cell stack and any one battery cell included in the second battery cell stack are electrically connected to each other through a center bus bar included in the center bus bar assembly, thereby forming a double cell structure; the battery cell stack includes at least one of the dual cell structures; a first external bus bar frame positioned on one side of the first battery cell stack and a second external bus bar frame positioned on one side of the second battery cell stack, electrode leads protruding from the battery cells included in the first battery cell stack toward the first external bus bar frame are connected to a first external bus bar attached to the first external bus bar frame; an electrode lead protruding from the battery cell included in the second battery cell stack toward the second external bus bar frame is connected to a second external bus bar attached to the second external bus bar frame.

10. the first external bus bar frame is positioned in a direction opposite to a direction in which the center bus bar assembly is disposed with respect to the first battery cell stack; The battery module of claim 9 , wherein the second outer bus bar frame is positioned in a direction opposite to a direction in which the center bus bar assembly is disposed, with respect to the second battery cell stack.

11. a first sensing unit and a second sensing unit for sensing a voltage are attached to the first external bus bar frame and the second external bus bar frame, respectively; The battery module of claim 9 , wherein a circuit unit connects at least one of the first sensing unit and the second sensing unit to the center bus bar.

12. the center bus bar includes a first portion connected to the electrode lead of the battery cell and a second portion extending from the first portion and connected to the circuit unit; The battery module of claim 11 , wherein the circuit unit extends to a lower end of the center bus bar assembly and is connected to the second portion of the center bus bar.

13. A battery cell stack including a first battery cell stack and a second battery cell stack, each of which has a plurality of battery cells stacked on top of one another; a center bus bar assembly disposed between the first battery cell stack and the second battery cell stack; A battery module comprising: the first battery cell stack and the second battery cell stack are arranged along a direction perpendicular to a direction in which the battery cells of the first battery cell stack or the second battery cell stack are stacked, any one battery cell included in the first battery cell stack and any one battery cell included in the second battery cell stack are electrically connected to each other through a center bus bar included in the center bus bar assembly, thereby forming a double cell structure; the battery cell stack includes at least one of the dual cell structures; The battery module further includes an upper insulating member disposed on an upper portion of the center bus bar assembly, the upper insulating member including an electrically insulating material.

14. 14. The battery module of claim 13, wherein the upper insulating member includes: a first wall portion facing the first battery cell stack; a second wall portion facing the second battery cell stack; and a bottom portion connecting the first wall portion and the second wall portion and facing the center bus bar assembly.

15. The center bus bar is arranged in plurality, the center bus bar assembly further includes a spacer disposed between the center bus bars and occupying a space between the center bus bars; The battery module according to claim 13 , wherein the spacer and the upper insulating member are assembled by engaging a hook.

16. A battery cell stack including a first battery cell stack and a second battery cell stack, each of which has a plurality of battery cells stacked on top of one another; a center bus bar assembly disposed between the first battery cell stack and the second battery cell stack; A battery module comprising: the first battery cell stack and the second battery cell stack are arranged along a direction perpendicular to a direction in which the battery cells of the first battery cell stack or the second battery cell stack are stacked, any one battery cell included in the first battery cell stack and any one battery cell included in the second battery cell stack are electrically connected to each other through a center bus bar included in the center bus bar assembly, thereby forming a double cell structure; the battery cell stack includes at least one of the dual cell structures; The battery module further includes a lower insulating member disposed below the center bus bar assembly, the lower insulating member including an electrically insulating material.

17. The center bus bar is arranged in plurality, the center bus bar assembly further includes a spacer disposed between the center bus bars and occupying a space between the center bus bars; The battery module according to claim 16 , wherein the spacer and the lower insulating member are assembled by engaging a hook.

18. A battery pack comprising the battery module according to any one of claims 1 to 17.

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