Cell assembly using longitudinally expanded structure of pouch-type battery cell and battery pack including the same

Abstract

According to the present invention, there may be provided a cell assembly including: a plurality of cell banks arranged in a row, each including one or two or more stacked pouch-type battery cells; a bridge bus bar unit disposed between the plurality of cell banks and electrically connecting the cell banks; and a cell cover partially surrounding and supporting a cell unit consisting of the plurality of cell banks and the bridge bus bar unit. Also, there may be provided a battery pack including the cell assembly, a pack tray on which the assembly is placed, and a pack cover coupled to the pack tray to cover the cell assembly.

Description

[Technical field]

[0001] The present invention relates to a battery, and more particularly to a cell assembly configured to allow pouch-type battery cells to be mounted directly on a pack case during assembly of a battery pack, without the need for a conventional battery module assembly process, and a battery pack including the same.

[0002] This application claims priority to Korean Patent Application No. 10-2021-0120657 filed on September 9, 2021, and Korean Patent Application No. 10-2022-0084492 filed on July 8, 2022, the entire contents of which are incorporated herein by reference in their entirety in the specification and drawings. [Background technology]

[0003] Secondary batteries are attracting attention as a new energy source not only because they have the primary advantage of dramatically reducing the use of fossil fuels, but also because they are environmentally friendly and can improve energy efficiency, as they do not produce any by-products associated with energy use.

[0004] Accordingly, secondary batteries are increasingly being applied to various devices. For example, they are widely used not only as energy sources for wireless mobile devices or wearable devices, which are multi-functional small products, but also as energy sources or energy storage systems (ESS) for electric vehicles and hybrid electric vehicles, which are presented as alternatives to existing gasoline and diesel vehicles.

[0005] Typically, the operating voltage of each secondary battery is about 2.5V to 4.5V. Therefore, in the case of electric vehicles and power storage devices that require large capacity and high output, a battery module in which a plurality of lithium secondary batteries are connected in series and / or parallel, and a battery pack in which the battery modules are connected in series and / or parallel are configured and used as an energy source. That is, a conventional battery pack includes a battery module as a subordinate concept, and a battery module includes a battery cell as a subordinate concept. The number of battery cells in a battery module or the number of battery modules in a battery pack can be determined in various ways depending on the output and capacity of the battery pack required for the electric vehicle.

[0006] As an example, a battery module of a battery pack for an electric vehicle may be housed inside a pack case including a cross beam as shown in FIG. 1. Here, the cross beam is a frame for reinforcing the rigidity of the pack case and acts to suppress deformation of the pack case, such as distortion of the pack case due to an external impact. The pack case may have an internal space partitioned by the cross beam, and a battery module may be disposed in the partitioned space S. Although FIG. 1 shows a battery module very simply, an actual battery module includes a plurality of battery cells, a bus bar for electrically connecting the plurality of battery cells, a sensing wire for sensing the voltage and temperature of the battery cells, and a module case for housing the above-mentioned components together. In addition, a BMS device for managing and controlling the charging and discharging of each battery module, and flexible bus bars and cables for connecting the battery modules to each other (not shown) are housed inside the pack case.

[0007] Meanwhile, pouch-type battery cells have some advantages such as being light in weight and having little dead space when stacked, but have problems such as being vulnerable to external impacts and being somewhat inferior in assembly. Therefore, in the case of a battery pack using pouch-type battery cells, it is common to stack a plurality of pouch-type battery cells to form a cell stack, electrically connect the stacked pouch-type battery cells, and package them in a module case to manufacture a battery module, and then store one or more of these battery modules in a pack case. For example, as disclosed in Patent Document 1, etc., a battery module included in a conventional battery pack is manufactured by stacking a plurality of pouch-type battery cells using various components such as a plastic stacking frame also called a cartridge, plates at both ends in the cell stacking direction, and fastening members such as bolts to form a cell stack, and then storing the cell stack inside a module case.

[0008] A conventional battery pack including such a battery module may be disadvantageous in terms of energy density. For example, in the process of modularizing a plurality of battery cells by housing them inside a module case, the volume of the battery module may be unnecessarily increased or the space occupied by the battery cells may be reduced due to a large number of components such as the module case or a stacking frame. Furthermore, the space occupied by the components themselves, such as the module case or the stacking frame, may be reduced in terms of the storage space of the battery cells in order to ensure assembly tolerances for such components. As a result, there is a limit to increasing the energy density when assembling a battery pack using such a battery module.

[0009] In addition, in the case of a conventional battery pack, since a module case is housed inside a pack case and battery cells are housed inside the module case, it is difficult to ensure excellent cooling performance. In particular, when the heat of the battery cells housed inside the module case is discharged to the outside of the pack case through the module case, the cooling efficiency is reduced and the cooling structure may become complicated.

[0010] However, as the electric vehicle market grows rapidly, more importance is being placed on the performance of electric vehicles and the maximum driving distance when fully charged. Therefore, there is a growing need for new battery packs with higher energy capacity and better battery cooling performance than conventional battery packs. In response to this, CTP (Cell To Pack, a method of directly assembling battery cells inside a battery pack case without the battery module unit) type battery packs have recently become an issue as a way to increase energy capacity, but until recently, there was no suitable method for mounting battery cells in a pack case for the CTP type. [Prior art documents] [Patent documents]

[0011] [Patent Document 1] Korean Patent Publication No. 10-2015-0044599 Summary of the Invention [Problem to be solved by the invention]

[0012] An object of the present invention is to provide a cell assembly that can be mounted in a CTP (Cell To Pack) type battery pack in a space-efficient manner.

[0013] Another object of the present invention is to provide a battery pack configured to maximize utilization of a storage space of a pack case by applying the cell assembly, thereby significantly improving energy capacity.

[0014] It is yet another object of the present invention to provide a battery pack and a vehicle having excellent energy density, ease of assembly, cooling performance, and / or safety.

[0015] However, the technical problems that the present invention aims to solve are not limited to the problems described above, and other problems not mentioned will be clearly understood by those skilled in the art from the description of the invention below. [Means for solving the problem]

[0016] According to one aspect of the present invention, there may be provided a cell assembly including a plurality of cell banks arranged in a row, each of which includes one or two or more stacked pouch-type battery cells, a bridge bus bar unit disposed between the plurality of cell banks and electrically connecting the cell banks to each other, and a cell cover partially surrounding and supporting a cell unit consisting of the plurality of cell banks and the bridge bus bar unit.

[0017] The multiple cell banks may include one or more first pouch-type battery cells forming one cell bank, and one or more second pouch-type battery cells forming another cell bank and arranged in a row with the first pouch-type battery cell along a longitudinal direction of the first pouch-type battery cell.

[0018] The cell cover may be configured to support the first pouch-type battery cell and the second pouch-type battery cell in an upright state.

[0019] The cell cover may be configured to partially surround the first pouch-type battery cell and the second pouch-type battery cell such that an upper portion or a lower portion of the first pouch-type battery cell and the second pouch-type battery cell are exposed.

[0020] The first pouch-type battery cell and the second pouch-type battery cell may include a receiving portion in which an electrode assembly is received and an edge portion around the receiving portion, and the cell cover may be provided to surround one of an upper edge portion and a lower edge portion of the first pouch-type battery cell and the second pouch-type battery cell and the receiving portion.

[0021] The cell cover may include a bottom cover part configured to surround bottom ends of lower edge parts of the first pouch-type battery cell and the second pouch-type battery cell, a first side cover part extending upward from one end of the bottom cover part and surrounding an outside of one side storage part of the first pouch-type battery cell and the second pouch-type battery cell, and a second side cover part extending upward from the other end of the bottom cover part at a position spaced apart from the first side cover part and surrounding an outside of the other side storage part of the first pouch-type battery cell and the second pouch-type battery cell.

[0022] The cell cover may include: an upper end cover part configured to surround upper ends of upper edge parts of the first pouch-type battery cell and the second pouch-type battery cell; a first side cover part extending downward from one end of the upper end cover part and surrounding an outside of one side storage part of the first pouch-type battery cell and the second pouch-type battery cell; and a second side cover part extending downward from the other end of the upper end cover part at a position spaced apart from the first side cover part and surrounding an outside of the other side storage part of the first pouch-type battery cell and the second pouch-type battery cell.

[0023] The first pouch-type battery cell and the second pouch-type battery cell may include a sealed portion and an unsealed portion as the edge portion, and the cell cover may be configured to surround at least a portion of the sealed portion for the first pouch-type battery cell and the second pouch-type battery cell, and to expose the unsealed portion.

[0024] The cell cover may have a length corresponding to a length of the first pouch-type battery cell, the bridge bus bar unit, and the second pouch-type battery cell arranged in a row in that order, and may include a notch partially recessed inwardly in at least one of an upper part and a lower part of a central region where the bridge bus bar unit is located.

[0025] The first pouch-type battery cell and the second pouch-type battery cell may be bidirectional pouch-type battery cells in which electrode leads protrude in both directions.

[0026] The first pouch-type battery cell may have an electrode lead of a first polarity connected to the bridge bus bar unit, and the second pouch-type battery cell may have an electrode lead of a second polarity connected to the bridge bus bar unit.

[0027] The bridge busbar unit includes a busbar housing made of an electrically insulating material and having a hollow tubular shape, and a busbar made of a conductive material and partially inserted into the busbar housing, and an electrode lead of the first pouch-type battery cell and an electrode lead of the second pouch-type battery cell may be in contact with each other so as to be fixed to one side and the other side of the busbar, respectively, inside the busbar housing.

[0028] The bus bar housing may include one or more slots provided on one side surface and an opposite side surface thereof so that electrode leads of the first pouch-type battery cell or the second pouch-type battery cell can be inserted therein, and an insertion opening provided on an upper surface thereof so that the bus bar can be inserted in a vertical direction.

[0029] The busbar housing may include openings for welding in the non-slotted side portions.

[0030] The bus bar may have a bent upper end portion, and the bent upper end portion may be configured to be exposed to an outside of the insertion opening.

[0031] The bus bar housing may be provided such that an upper surface portion thereof is located at a height lower than upper ends of the first pouch-type battery cell and the second pouch-type battery cell.

[0032] According to another aspect of the present invention, a battery pack may be provided, including: a cell assembly group in which the above-mentioned cell assemblies are stacked in a first direction; a pack case including a pack tray on which the cell assembly group is placed and a pack cover that is coupled to the pack tray to cover the cell assembly group; and a voltage sensing unit extending in the first direction, disposed on top of the cell assembly group, and electrically connected to a bus bar provided in the bridge bus bar unit of each of the cell assembly groups.

[0033] The cell assemblies may be adhesively mounted to the upper surface of the pack tray.

[0034] the voltage sensing unit includes: a sensing frame made of an insulating material, disposed on an upper portion of the bridge bus bar unit, the sensing frame having sensing holes formed by drilling for each area where the bridge bus bar unit is located; and a sensing circuit board disposed on the upper portion of the sensing frame, The sensing terminals of the sensing circuit board may pass through the sensing holes and be electrically connected to the bus bars of the bridge bus bar unit.

[0035] The cell assembly group may include a first cell assembly group and a second cell assembly group, and may include a first cross beam extending between the first cell assembly group and the second cell assembly group in a second direction intersecting the first direction and fixedly connected to the pack tray.

[0036] The pack tray may include a second cross beam located above the voltage sensing unit, extending in the first direction, and fixedly coupled to the pack tray.

[0037] The pack case may include a heat sink, and a thermal resin may be provided between the first pouch-type battery cell and the heat sink, and between the second pouch-type battery cell and the heat sink.

[0038] The heat sink may include an upper heat sink and a lower heat sink disposed on an upper portion and a lower portion of the cell cover, respectively.

[0039] The cell cover may be configured such that at least one side end is sandwiched and coupled to the pack case.

[0040] The cell assembly may have a directional venting space inside the cell cover through which gas can move from at least one end in a longitudinal direction to an upper portion or a lower portion of the cell cover.

[0041] The pack case may include a gas exhaust port communicating with the directional venting space.

[0042] A burst disc may be attached to the gas exhaust port, which bursts under a predetermined pressure or heat.

[0043] According to yet another aspect of the present invention, there may be provided a vehicle including the battery pack described above. Effect of the Invention

[0044] According to the present invention, it is possible to provide a cell assembly embodied in the form of a long cell in which one or more pouch-type battery cells and one or more other pouch-type battery cells are integrated by connecting them in a longitudinal direction using a bridge bus bar unit.

[0045] By using this cell assembly, the pouch-type battery cell can be directly assembled into the pack case of the battery pack, thereby maximizing the space utilization rate of the battery pack and significantly improving the energy capacity.

[0046] That is, according to an embodiment of the present invention, a module case of a battery module is omitted when constructing a battery pack, and therefore, the space occupied by the module case can be reduced and more battery cells can be disposed inside the pack case, thereby further improving the energy density of the battery pack.

[0047] In addition, the present invention can improve the ease of assembly of a battery pack. In particular, according to one embodiment of the present invention, it is not necessary to perform a process of accommodating pouch-type battery cells in a module case to provide a battery module, and a process of accommodating one or more battery modules thus provided in a pack case. This simplifies the manufacturing process and reduces manufacturing time.

[0048] In addition, according to the present invention, a configuration in which a plurality of pouch-type battery cells are stacked in a horizontal direction in a vertically upright state in a pack case of a battery pack can be easily and stably implemented.

[0049] In addition, according to the present invention, in the process of housing a soft pouch-type battery cell inside a pack case, the cell cover can be gripped without directly gripping the pouch-type battery cell. This makes the handling process of the pouch-type battery cell easier and safer. Furthermore, in this case, damage or breakage of the pouch-type battery cell can be prevented in the cell handling process, such as housing the pouch-type battery cell inside the pack case.

[0050] In addition, according to the present invention, the cooling efficiency of the battery pack can be further improved. In particular, in one embodiment of the present invention, a portion of each pouch-type battery cell is directly exposed to the pack case, so that heat of each pouch-type battery cell can be effectively discharged to the outside through the pack case.

[0051] Additionally, one embodiment of the present invention allows for additional surface cooling via the broad surface area of ​​the pouch-type battery cell.

[0052] Also, according to one aspect of the present invention, the safety of the battery pack is improved. In particular, according to one embodiment of the present invention, gas and the like discharged from each battery cell can be smoothly discharged to the outside. Furthermore, according to one embodiment of the present invention, the discharge direction of gas and flames discharged from the battery cell can be controlled. Therefore, the propagation of thermal runaway to adjacent battery cells can be effectively prevented.

[0053] In addition, the present invention provides various other effects, which will be described in each embodiment, and descriptions of effects that can be easily inferred by those skilled in the art will be omitted. [Brief description of the drawings]

[0054] [Figure 1] FIG. 1 is a diagram showing a simplified configuration of a battery pack according to the prior art. [Diagram 2] FIG. 2 is a perspective view showing a configuration of a cell assembly according to an embodiment of the present invention. [Diagram 3] 1 is a perspective view showing a cell unit and a cell cover separated according to an embodiment of the present invention; [Figure 4] FIG. 4 is an exploded perspective view of the first pouch-type battery cell and the second pouch-type battery cell and the bridge bus bar unit of FIG. 3. [Diagram 5] FIG. 5 is an exploded perspective view of the bridge bus bar unit of FIG. 4. [Figure 6] FIG. 4 is an enlarged view of region A in FIG. [Figure 7] 6A, 6B, and 6C are diagrams respectively showing the upper part, one side part, and the other side part of the bridge bus bar unit in FIG. 5. [Figure 8] FIG. 2 is a top view of a central region of a cell assembly according to one embodiment of the present invention. [Figure 9] FIG. 9 is a bottom view of the central region of the cell assembly of FIG. 8. [Figure 10]FIG. 2 is a perspective view showing one cell assembly group formed by stacking four cell assemblies according to an embodiment of the present invention. [Figure 11] FIG. 11 is a cutaway view of the cell assembly group taken along line BB' of FIG. [Figure 12] 1 is a perspective view showing a schematic configuration of a battery pack according to an embodiment of the present invention; [Figure 13] FIG. 2 is a perspective view showing the configuration of a plurality of cell assembly groups, a first cross beam, and a pack tray in a battery pack according to an embodiment of the present invention. [Figure 14] 13 is a perspective view showing a voltage sensing unit and a second cross beam separated from the state shown in FIG. 12. FIG. [Figure 15] 2 is a diagram illustrating an assembly structure of a bridge busbar unit and a voltage sensing unit in a battery pack according to an embodiment of the present invention. FIG. [Figure 16] 2 is a diagram illustrating an assembly structure of a bridge busbar unit and a voltage sensing unit in a battery pack according to an embodiment of the present invention. FIG. [Figure 17] FIG. 11 is an exploded perspective view of the main components of a cell assembly according to another embodiment of the present invention. [Figure 18] FIG. 2 is a perspective view of a cell assembly according to another embodiment of the present invention. [Figure 19] FIG. 19 is a top view of the central region of the cell assembly of FIG. 18. [Figure 20] FIG. 19 is a bottom view of the central region of the cell assembly of FIG. 18. [Figure 21] FIG. 13 is a perspective view of a cell assembly group formed by stacking four cell assemblies according to another embodiment of the present invention. [Figure 22] FIG. 22 is a partially exploded perspective view of the cell assembly group of FIG. 21. [Diagram 23] FIG. 2 is a perspective view illustrating a schematic configuration of a battery pack according to another embodiment of the present invention. [Figure 24] FIG. 2 is an exploded perspective view of a main configuration of a battery pack according to another embodiment of the present invention. [Diagram 25] FIG. 4 is a diagram illustrating a cooling structure of a battery pack according to another embodiment of the present invention. [Figure 26] 11A and 11B are diagrams showing modified examples of cell covers in a battery pack according to another embodiment of the present invention. [Figure 27] 13A and 13B are diagrams showing modified examples of the pack tray in the battery pack according to another embodiment of the present invention. [Figure 28] FIG. 11 is a bottom view of one end region of a cell assembly group in a battery pack according to another embodiment of the present invention. [Figure 29] FIG. 13 is a schematic diagram illustrating a gas venting configuration of a battery pack according to another embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0055] Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the attached drawings. Prior to this, the terms and words used in the specification and claims should not be interpreted as being limited to their ordinary or dictionary meanings, but should be interpreted as having meanings and concepts according to the technical ideas of the present invention, in accordance with the principle that the inventor himself can appropriately define the concepts of terms in order to best describe the invention.

[0056] In addition, the embodiments described in this specification and the configurations shown in the drawings are merely the most preferred embodiments of the present invention and do not represent all of the technical ideas of the present invention, so it should be understood that there may be various equivalents and modifications that can be substituted for them at the time of filing this application. The size of each component or a specific part constituting a component in the drawings may be exaggerated, omitted, or shown in a schematic manner for convenience and clarity of description. Therefore, the size of each component does not completely reflect the actual size. If a detailed description of a known function or configuration related to the present invention is determined to unnecessarily blur the gist of the present invention, the description will be omitted.

[0057] The terms "coupled" or "connected" as used herein include not only cases where one member is directly coupled or connected to another member, but also cases where one member is indirectly coupled or connected to another member via a joint member.

[0058] A cell assembly according to the present invention may include a plurality of cell banks arranged in a row, each of which has one or two or more stacked pouch-type battery cells, a bridge bus bar unit 120 disposed between the plurality of cell banks and electrically connecting the cell banks to each other, and a cell cover 130 that partially surrounds and supports a cell unit consisting of the plurality of cell banks and the bridge bus bar unit 120.

[0059] Here, the cell bank refers to one pouch-type battery cell 110 or a group of pouch-type battery cells in which two or more pouch-type battery cells 110 are stacked and electrically connected in parallel. That is, in this specification, a first pouch-type battery cell 110A corresponds to one cell bank, and a second pouch-type battery cell 110B corresponds to another cell bank.

[0060] The embodiment described below is merely a preferred embodiment of the present invention and does not represent all of the technical ideas of the present invention. That is, unlike the embodiment described below, the cell assembly of the present invention may be configured to include three or more cell banks. Therefore, the scope of the present invention should not be interpreted as being limited to only the cell assembly 100 in which the first pouch-type battery cell 110A and the second pouch-type battery cell 110B are connected in series as two cell banks arranged in a row and partially surrounded by the cell cover 130.

[0061] FIG. 2 is a perspective view showing the configuration of a cell assembly 100 according to one embodiment of the present invention, FIG. 3 is a perspective view showing a cell unit and a cell cover 130 separated according to one embodiment of the present invention, and FIG. 4 is an exploded perspective view of the first pouch-type battery cell 110A and the second pouch-type battery cell 110B and the bridge bus bar unit 120 of FIG. 3.

[0062] 2 to 4, a cell assembly 100 according to an embodiment of the present invention includes one or more first pouch-type battery cells 110A, one or more second pouch-type battery cells 110B arranged in a row with the first pouch-type battery cell 110A along a longitudinal direction (X direction) of the first pouch-type battery cell 110A, a bridge bus bar unit 120 arranged between the first pouch-type battery cell 110A and the second pouch-type battery cell 110B and electrically connecting the first pouch-type battery cell 110A and the second pouch-type battery cell 110B, and a cell cover 130 partially surrounding and supporting a cell unit consisting of the first pouch-type battery cell 110A, the bridge bus bar unit 120, and the second pouch-type battery cell 110B.

[0063] The pouch-type battery cell 110 includes an electrode assembly, an electrolyte, a pouch exterior material for hermetically storing the electrode assembly and the electrolyte, and an electrode lead 111 connected to the electrode assembly and drawn out to the outside of the pouch exterior material. The electrode lead 111 includes a pair of a positive electrode lead 111A and a negative electrode lead 111B. Here, the positive electrode lead 111A and the negative electrode lead 111B are provided at both ends of the battery cell in the longitudinal direction (X-axis direction) of the battery cell. The pouch-type battery cell 110 including the pair of electrode leads 111 configured in this manner is referred to as a bidirectional pouch-type battery cell 110. The cell assembly 100 according to an embodiment of the present invention may be formed of the bidirectional pouch-type battery cell 110.

[0064] The first pouch-type battery cell 110A may be composed of one pouch-type battery cell 110 or two or more pouch-type battery cells 110 stacked to face each other. For example, as shown in FIG. 2 and FIG. 3 of this embodiment, three pouch-type battery cells 110 may be stacked in a first direction (Y-axis direction) to form a group of first pouch-type battery cells 110A. Also, the electrode leads 111 of the same polarity may all be positioned in the same direction so that the three pouch-type battery cells 110 are connected in parallel (3P) to form one bank. That is, as shown in FIG. 3, three positive electrode leads 111A may be stacked, and similarly, three negative electrode leads 111B may be stacked to form one bank of three first pouch-type battery cells 110A.

[0065] The second pouch-type battery cell 110B may be composed of the same number of pouch-type battery cells as the first pouch-type battery cell 110A. That is, the second pouch-type battery cell 110B may also be composed of one pouch-type battery cell 110 or two or more pouch-type battery cells 110 stacked to face each other. For example, a group of second pouch-type battery cells 110B may be configured by stacking three pouch-type battery cells 110 to form a bank, similar to the three first pouch-type battery cells.

[0066] The first pouch-type battery cell 110A of the group and the second pouch-type battery cell 110B of the other group may be configured to be connected in series to each other by electrically connecting the negative electrode lead 111B of the first pouch-type battery cell 110A and the positive electrode lead 111A of the second pouch-type battery cell 110B. From an electrical point of view, the configuration of the first pouch-type battery cell 110A and the second pouch-type battery cell 110B is a 3P2S type connected in series and parallel, and from a structural point of view, it can be said to be a type of one long cell connected in the longitudinal direction and integrated.

[0067] Meanwhile, as an example different from the above-mentioned embodiment, the cell assembly 100 according to the present invention may be embodied in the form of an nPmS (n is a natural number, m is a natural number of 2 or more) electrically formed by connecting the pouch-type battery cells 110 in the longitudinal direction, and structurally in the form of an integrated long cell. That is, for example, the cell assembly 100 may be embodied in a form in which the number of parallel connections is increased to 1P, 2P, 3P, etc. according to the thickness of the pouch-type battery cells 110, or the number of series connections is increased to 2S, 3S, S, etc. according to the length of the pouch-type battery cells 110. In this case, the cell assembly 100 may be arranged in a row with the first pouch-type battery cell 110A and the second pouch-type battery cell 110B, and may further include another group of pouch-type battery cells and a bridge bus bar unit 120.

[0068] For convenience of explanation, the electrode leads 111 are hereinafter classified into a first polarity electrode lead 111 and a second polarity electrode lead 111. Here, the first polarity and the second polarity are a relative classification of the polarity of the electrode leads 111. That is, when the first polarity is a positive electrode, the second polarity means a negative electrode, and conversely, when the first polarity is a negative electrode, the second polarity means a positive electrode.

[0069] The bridge bus bar unit 120 may be configured so that the electrode leads 111 of the first polarity of the first pouch-type battery cell 110A are stacked together and connected to one side, and the electrode leads 111 of the second polarity of the second pouch-type battery cell 110B are stacked together and connected to the other side.

[0070] 3 and 4, the first pouch-type battery cell 110A may have a negative electrode lead 111B connected to the left side of the bridge bus bar unit 120 in the +X-axis direction, and the second pouch-type battery cell 110B may have a positive electrode lead 111A connected to the right side of the bridge bus bar unit 120 in the -X-axis direction. The positive electrode lead 111A and the negative electrode lead 111B may be welded to a surface of a bus bar 123 inside the bridge bus bar unit 120 and electrically connected to each other.

[0071] More specifically, as shown in FIG. 5, the bridge busbar unit 120 includes a busbar housing 121 and a busbar 123 with a bent upper end 123a.

[0072] The bus bar housing 121 may be made of an electrically insulating material and may be formed in a hollow rectangular tubular shape. The bus bar housing 121 may have an insertion opening 121a at an upper surface into which the bus bar 123 is inserted in the vertical direction, one or more slots 121b at one side surface and the opposite side surface into which the electrode leads 111 of the first pouch-type battery cell 110A and the second pouch-type battery cell 110B are inserted, and openings 121c for welding at both side surfaces where the slots 121b are not present.

[0073] In addition, the bus bar housing 121 may be provided with a height lower than the width in the width direction (Z-axis direction) of the first pouch type battery cell 110A and the second pouch type battery cell 110B. When the bridge bus bar unit 120 and the first pouch type battery cell 110A and the second pouch type battery cell 110B are assembled using the bus bar housing 121, the upper surface portion of the bus bar housing 121 is positioned lower than the upper ends of the first pouch type battery cell 110A and the second pouch type battery cell 110B, as shown in Fig. 5. As will be described later, an upper space of the bridge bus bar unit 120 secured by such a configuration may be used as an installation space for the voltage sensing unit 30 and the second cross beam 50 when the battery pack 1 is assembled.

[0074] 6, the bus bar housing 121 includes a recess 121e formed by recessing a lower surface portion toward the upper side (Z-axis direction). The recess 121e can be used as a space for avoiding interference with a third cross beam 24 provided on the pack tray 21 when the battery pack 1 is assembled later.

[0075] The bus bar 123 is made of a metal material having electrical conductivity such as copper or nickel, and is provided in a rod shape with a bent upper end. The remaining portion of the bus bar 123, except for the bent upper end 123a, is inserted into the bus bar housing 121 through the insertion opening 121a. The insertion opening 121a is provided with a size equal to or slightly larger than the cross-sectional area of ​​the bus bar 123, and is configured so that the bent upper end 123a of the bus bar 123 is not inserted. According to this configuration, the bent upper end 123a of the bus bar 123 may be placed on a receiving portion 121d of the bus bar housing 121 provided around the insertion opening 121a, and may be arranged so that the upper surface faces upward. By exposing the bent upper end 123a of the bus bar 123 to the outside of the bus bar housing 121 in this manner, the sensing terminal of the voltage sensing unit 30 can be easily brought into contact with the bus bar 123 when the battery pack 1 is later assembled.

[0076] As in the embodiment shown in FIGS. 6 and 7, the first pouch-type battery cell 110A and the second pouch-type battery cell 110B may extend in opposite directions from each other around the bridge busbar unit 120 and be electrically connected in series.

[0077] As shown in (a) of FIG. 7, the negative electrode lead 111B of the first pouch-type battery cell 110A can be inserted into the bus bar housing 121 through a slot 121b on one side of the bus bar housing 121, and the positive electrode lead 111A of the second pouch-type battery cell 110B can be inserted into the bus bar housing 121 through the slot 121b on the other side of the bus bar housing 121.

[0078] The negative electrode lead 111B of the first pouch-type battery cell 110A inserted into the bus bar housing 121 in this manner may come into contact with one side of the bus bar 123 so as to be fixed thereto by laser welding. For example, as shown in Fig. 7(b), a welding laser beam may be irradiated onto the negative electrode lead 111B from an opening 121c on one side of the bus bar housing 121, so that the negative electrode lead 111B may be welded to one side of the bus bar 123.

[0079] The positive electrode lead 111A of the second pouch-type battery cell 110B inserted inside the bus bar housing 121 may be fixed to and contacted with the other side of the bus bar 123 by laser welding. Similar to the negative electrode lead 111B of the first pouch-type battery cell 110A, a welding laser beam may be irradiated onto the positive electrode lead 111A from the opening 121c on the other side of the bus bar housing 121 as shown in FIG. 7(c) , and the positive electrode lead 111A may be welded to the other side of the bus bar 123.

[0080] Meanwhile, the cell cover 130 may be configured to partially surround the first pouch type battery cell 110A and the second pouch type battery cell 110B such that at least one side of the first pouch type battery cell 110A and the second pouch type battery cell 110B is exposed to the outside. That is, the cell cover 130 may be configured to surround only a part of the first pouch type battery cell 110A and the second pouch type battery cell 110B, rather than entirely. The reason for configuring the cell cover 130 in this manner is to easily assemble the first pouch type battery cell 110A and the second pouch type battery cell 110B to the cell cover 130, and further, to expose at least one side of the first pouch type battery cell 110A and the second pouch type battery cell 110B to the pack case 20 when assembling the cell assembly 100 to the pack case 20.

[0081] For example, referring to the embodiment of Figures 2 and 3, the cell cover 130 may be configured to surround a cell unit formed by arranging the first pouch-type battery cell 110A, the bridge busbar unit 120, and the second pouch-type battery cell 110B in a row in that order, and the upper part of the cell unit may be configured not to be surrounded.

[0082] 12, when assembling the battery pack, the cell assembly 100 is placed on the pack tray 21 so that the upper edge portions E1 of the first pouch-type battery cell 110A and the second pouch-type battery cell 110B face the pack cover 22, and the upper edge portions E1 are coated with thermal resin to cover the pack cover, so that the heat released from each pouch-type battery cell 110 is directly transferred to the pack cover 22 via the thermal resin. With this configuration, there is no need to provide a separate cooling structure between the pouch-type battery cell 110 and the pack case 20, making the cooling configuration simple and efficient.

[0083] 2 to 4, the pouch-type battery cell 110 may have a storage portion indicated by R and edge portions indicated by E1 to E4. Here, the storage portion R may be a portion that stores an electrode assembly configured such that a positive electrode plate and a negative electrode plate are stacked on each other with a separator interposed therebetween. Also, an electrolyte may be stored in the storage portion R. And, the edge portions E1 to E4 may be arranged to surround the periphery of the storage portion R.

[0084] In particular, the edge portion may be a sealing portion where the pouch exterior material, which is the case of the pouch-type battery cell 110, is sealed. For example, in FIG. 4, four edge portions may be provided, and may be located at the upper edge, the lower edge, the front edge, and the rear edge, respectively, based on the storage portion R. In this case, the four edge portions E1 to E4 may all be sealing portions. Alternatively, some of the four edge portions E1 to E4 may be configured by folding, rather than being sealed. For example, in the embodiment of FIG. 4, the lower edge portion E2 may be a portion where the pouch exterior material is folded, and the upper edge portion E1, the front edge portion E3, and the rear edge portion E4 may all be sealing portions. Here, a battery cell in which all four edge portions E1 to E4 are sealed may be referred to as a four-side sealed cell, and a battery cell in which three edge portions E1, E3, and E4 are sealed may be referred to as a three-side sealed cell.

[0085] In this configuration, the cell cover 130 may be configured to surround both sides of the storage portion R and parts of the edge portions E1 to E4 of the first pouch-type battery cell 110A and the second pouch-type battery cell 110B. For example, when one cell cover 130 is configured to surround a plurality of stacked pouch-type battery cells 110, it may be configured to surround the outer surface of the storage portion of the outermost pouch-type battery cell 110 and the entire upper or lower edge portion of the pouch-type battery cell 110.

[0086] 2 and 3, one cell cover 130 may be configured to surround three first pouch-type battery cells 110A and three second pouch-type battery cells 110B stacked in the left-right direction (±Y direction). In this case, the cell cover 130 may be configured to surround the outer surface of the storage portion R of the leftmost battery cell in the first pouch-type battery cell 110A and the second pouch-type battery cell 110B, the lower edge portion E2 of the first pouch-type battery cell 110A and the second pouch-type battery cell 110B, and the outer surface of the storage portion R of the rightmost battery cell in the first pouch-type battery cell 110A and the second pouch-type battery cell 110B.

[0087] Meanwhile, as an example different from the present embodiment, the cell cover 130 may be configured to surround the upper edge portion E1, not the lower edge portion E2, of the first pouch type battery cell 110A and the second pouch type battery cell 110B. As yet another example, when one cell cover 130 is configured to surround the first pouch type battery cell 110A and the second pouch type battery cell 110B each composed of one pouch type battery cell 110, the cell cover 130 may be configured to surround both side surfaces (e.g., the left and right surfaces of the same housing portion R) and the upper edge portion E1 or the lower edge portion E2 of the one pouch type battery cell 110.

[0088] According to this embodiment, a configuration for supporting and protecting one or more pouch-type battery cells 110 can be easily implemented as one cell cover 130. Also, according to the embodiment, a process of handling one or more pouch-type battery cells 110 can be easily and safely performed by the cell cover 130. Also, according to the embodiment, one cell cover 130 can face the surfaces of two storage parts R with respect to the pouch-type battery cells 110 accommodated therein. This can further improve the cooling performance between the storage parts R and the cell cover 130. In particular, in this case, surface cooling is implemented due to the wide surface of the storage part R, improving the cooling efficiency.

[0089] In addition, the cell cover 130 may be configured not to surround edges located at both ends in the longitudinal direction (±X direction) of the first pouch-type battery cell 110A and the second pouch-type battery cell 110B housed therein. That is, the cell cover 130 may be configured to surround one of the upper edge portion E1 and the lower edge portion E2 of the first pouch-type battery cell and the second pouch-type battery cell, except for the front edge portion E3 of the first pouch-type battery cell 110A where the electrode lead of the first polarity is located and the rear edge portion E4 of the second pouch-type battery cell 110B where the electrode lead of the second polarity is located.

[0090] According to this embodiment of the present invention, the direction of the discharge of flames, etc., can be guided to the exposed side of the cell cover 130. For example, according to this embodiment, since the front and rear of the cell cover 130 where the electrode lead 111 is located are open, flames, etc. can be discharged in the direction of the opening. In particular, when the cell cover 130 is configured in such a manner that the front and rear are open as described above, side directional venting can be easily implemented.

[0091] The cell cover 130 may be configured to partially surround a cell unit including a first pouch-type battery cell 110A, a bridge bus bar unit 120, and a second pouch-type battery cell 110B arranged in a row.

[0092] 2 and 3, 8 and 9, the cell cover 130 may be configured in a substantially U-shape so as to tightly press the outermost surfaces of both sides of the first pouch type battery cell 110A and the second pouch type battery cell 110B in order to support the first pouch type battery cell 110A and the second pouch type battery cell 110B in a standing state in a row, and to expose the upper edge portion E1 of the first pouch type battery cell 110A and the second pouch type battery cell 110B. The cell cover 130 may play a role in preventing the first pouch type battery cell 110A and the second pouch type battery cell 110B from twisting clockwise or counterclockwise around the bridge bus bar unit 120 when subjected to external impact or vibration.

[0093] In addition, the cell cover 130 may be configured to have excellent mechanical rigidity and be provided as a thin plate having a small thickness, thereby minimizing space loss during subsequent assembly of the battery pack 1. For example, if the cell cover 130 is made of a metal material having excellent rigidity such as steel, particularly a SUS material, the upright state of the cell unit may be more stably maintained. As a result, during subsequent assembly of the cell unit into the battery pack 1, the upright state of the cell unit may be more reliably supported.

[0094] More specifically, the cell cover may include a bottom cover part 131, a first side cover part 132 and a second side cover part 133 as shown in FIGS.

[0095] Here, the lower end cover part 131 may be configured to surround the lower part of the lower edge part E2 of the first pouch type battery cell 110A and the second pouch type battery cell 110B housed therein. In particular, the lower end cover part 131 may be configured to contact or be spaced apart from the lower edge part E2 of the first pouch type battery cell 110A and the second pouch type battery cell 110B. In addition, the lower end cover part 131 may be configured in a flat shape.

[0096] The first side cover part 132 may be configured to extend upward from one end (in the +Y direction) of the lower end cover part 131. For example, the first side cover part 132 may be configured to extend upward (in the +Z direction in the drawing) from a left end part of the lower end cover part 131. The first side cover part 132 may be formed in a flat shape.

[0097] The first side cover part 132 may be configured to surround the outside of one side of the housing part R of the first pouch-type battery cell 110A and the second pouch-type battery cell 110B housed inside the cell cover 130. Here, the first side cover part 132 may be disposed in direct contact with the outer surface of the housing part R or may be attached by an adhesive.

[0098] The second side cover part 133 may be configured to be positioned horizontally apart from the first side cover part 132 and extend upward from the other end (-Y direction) of the lower end cover part 131. For example, the second side cover part 133 may be configured to extend upward (+Z direction in the drawing) from the right end part of the lower end cover part 131. Furthermore, the second side cover part 133 may be configured in a planar shape like the first side cover part 132. In this case, the second side cover part 133 and the first side cover part 132 may be configured parallel to each other.

[0099] The second side cover part 133 may be configured to surround the outside of the other side storage part R of the first pouch-type battery cell 110A and the second pouch-type battery cell 110B stored inside the cell cover 130. Here, the second side cover part 133 may be disposed in direct contact with the outer surface of the storage part or may be attached by an adhesive.

[0100] The cross-sectional areas of the first and second side cover parts 132 and 133 are larger than the cross-sectional areas of the first pouch-type battery cell 110A and the second pouch-type battery cell 110B arranged in a row facing the first and second side cover parts 132 and 133, thereby preventing the storage part R from being exposed to the outside and ensuring maximum safety.

[0101] Also, the cell cover 130 may be provided to have a length corresponding to the length of the first pouch-type battery cell 110A, the bridge bus bar unit 120, and the second pouch-type battery cell 110B arranged in a row in this order. For example, as shown in FIG. 3, the cell cover 130 may be configured to extend from one end of the first pouch-type battery cell 110A to the other end of the second pouch-type battery cell 110B. For reference, unlike the present embodiment, when a group of pouch-type battery cells 110 are expanded in the longitudinal direction to form a cell assembly 100 such as 3S, 4S, ..., the cell cover 130 may be configured to have a length capable of housing all of the pouch-type battery cells 110 expanded in the longitudinal direction.

[0102] In particular, the cell cover 130 according to this embodiment may have notches 135 and 136 that are partially cut inward at at least one of the upper and lower ends where the bridge bus bar unit 120 is housed.

[0103] The cell cover 130 according to this embodiment may have notches at two locations, the upper and lower ends of the cell cover 130, as shown by circles in Fig. 3. Hereinafter, the notch at the upper end of the cell cover 130 will be referred to as an upper notch 135, and the notch at the lower end of the cell cover 130 will be referred to as a lower notch 136.

[0104] As shown in FIG. 2, the cell assembly 100 according to this embodiment may be provided with a central region where the bridge bus bar unit 120 is located recessed inward.

[0105] For example, in the bridge busbar unit 120, the upper surface of the busbar housing 121 is configured to be lower in height than the upper edge portions E1 of the first pouch-type battery cell 110A and the second pouch-type battery cell 110B as shown in FIG. 6, so that when stored in the cell cover 130, it does not protrude above the upper notch 135 as shown in FIG. 8, and the lower surface of the busbar housing 121 is configured not to protrude below the lower notch 136 as shown in FIG. 9.

[0106] When a plurality of cell assemblies 100 configured as described above are stacked to form a cell assembly group 10 as shown in Fig. 10, the cell assembly group 10 has a valley-shaped structure in which the upper notch 135 and the lower notch 136 of each cell assembly 100 are aligned in one direction (±Y direction). This valley-shaped structure can be used as an installation space for the voltage sensing unit 30, the second cross beam 50, and the third cross beam 24 when assembling the battery pack 1 as shown in Figs. 12 to 14.

[0107] Meanwhile, when a plurality of cell assemblies 100 having the above-mentioned configuration are stacked in a first direction, a cell assembly group 10 can be provided as shown in Fig. 10. Specifically, the cell assembly group 10 shown in Fig. 10 is configured by stacking four cell assemblies 100 in a first direction (Y direction). In this case, as shown in Fig. 11, the electrode leads 111 of the first polarity of the first pouch-type battery cells 110A of each cell assembly 100 are stacked and fixed to one side of the bus bar 123 of each bridge bus bar unit 120, and the electrode leads 111 of the second pouch-type battery cells 110B are stacked and fixed to the other side of the bus bar 123 of each bridge bus bar unit 120, and connected in series.

[0108] A front busbar unit 200 and a rear busbar unit 300 may be used to electrically connect the four cell assemblies 100. As shown in Fig. 10, the front busbar unit 200 includes a front busbar housing made of an insulating material configured to integrally cover front portions of the four cell assemblies 100 along the +X-axis direction, and a plurality of plate-shaped busbars attached to the front busbar housing, and the rear busbar unit 300 includes a rear busbar housing made of an insulating material configured to integrally cover rear portions of the four cell assemblies 100 along the -X-axis direction, and a plurality of rectangular busbars attached to the rear busbar housing.

[0109] The front bus bar housing and the rear bus bar housing each have a slot in the Y-axis direction, and the electrode lead 111 can be inserted into the slot and pulled out to the outside of the bus bar housing, and the pulled out portion can be welded to a plate-shaped bus bar. The four cell assemblies 100 can also be electrically connected to each other by the front bus bar unit 200 and the rear bus bar unit 300.

[0110] FIG. 12 is a perspective view showing a schematic configuration of a battery pack 1 according to one embodiment of the present invention, FIG. 13 is a perspective view showing the configuration of multiple cell assembly groups 10A, 10B, a first cross beam 40, and a pack tray 21 in a battery pack according to one embodiment of the present invention, FIG. 14 is a perspective view showing the voltage sensing unit 30 and the second cross beam 50 separated in FIG. 12, and FIGS. 15 and 16 are views for explaining the assembly structure of the bridge bus bar unit 120 and the voltage sensing unit 30 in a battery pack according to one embodiment of the present invention.

[0111] Hereinafter, the battery pack 1 according to the present invention configured by applying the above-mentioned cell assembly 100 will be described in detail with reference to the drawings.

[0112] A battery pack 1 according to one embodiment of the present invention includes a plurality of cell assembly groups 10 each stacked in a first direction (Y direction), a pack case 20 for accommodating the plurality of cell assembly groups 10, a voltage sensing unit 30, cross beams 24, 40, 50, and a battery control system 60.

[0113] The group of multiple cell assemblies 10 can be said to be an assembly of the above-mentioned cell assemblies 100, and can be housed inside a pack case 20 as shown in FIG.

[0114] The plurality of cell assembly groups 10 may be divided into a first cell assembly group 10A and a second cell assembly group 10B. The reason why the plurality of cell assembly groups 10 are divided into the first cell assembly group 10A and the second cell assembly group 10B is to conveniently distinguish between those located in the +Y-axis direction and those located in the -Y-axis direction based on the first cross beam 40 of the pack tray 21 in Figures 12 and 13.

[0115] The pack case 20 may be composed of a pack tray 21 and a pack cover 22 .

[0116] The pack tray 21 may include a bottom plate 21B having a substantially wide rectangular shape and four side plates forming a wall along the periphery of the bottom plate 21B. The pack tray 21 may include a first cross beam 40, a second cross beam 50, a third cross beam 24, and a partition wall 23, which may be integrally provided or additionally assembled. The first cross beam 40, the second cross beam 50, the third cross beam 24, and the partition wall 23 may play a role in supporting the bottom plate 21B and the side plates of the pack tray 21 when an external shock or vibration occurs, thereby preventing deformation such as twisting of the pack tray 21. That is, the mechanical rigidity of the pack tray 21 may be increased by adding the first cross beam 40, the second cross beam 50, the third cross beam 24, and the partition wall 23.

[0117] As shown in Fig. 13, the cell assembly 100 may be accommodated in a space surrounded by the bottom plate 21B, the partition wall 23, the side plate in the -X-axis direction, and the side plate in the ±Y-axis direction inside the pack tray 21. Here, the cell assembly 100 refers to a configuration in which the first pouch-type battery cell 110A, the bridge bus bar unit 120, and the second pouch-type battery cell 110B arranged in a row are partially surrounded by the cell cover 130 to form a long cell. Such cell assemblies 100 are stacked to form a cell assembly group 10, and a plurality of cell assembly groups 10 are closely arranged on the pack tray 21, thereby minimizing the dead space in the pack tray 21.

[0118] The cell assembly group 10 may be configured to be bonded and fixed to the bottom plate 21B of the pack tray 21. To this end, the bottom plate 21B of the pack tray 21 may be provided with an adhesive G or an adhesive sheet. Here, the adhesive may be a thermal resin. Preferably, the adhesive G or adhesive sheet may have excellent thermal conductivity. In this case, heat from the pouch-type battery cell 110 can be more effectively dissipated to the outside. Although not shown, a heat sink may be disposed between the adhesive and the bottom plate 21B of the pack tray 21, or a heat sink may be attached under the bottom plate 21B of the pack tray 21 to absorb heat dissipated from the pouch-type battery cell 110.

[0119] The pack cover 22 is provided to be able to shield other components including a plurality of cell assembly groups 10, and may be configured to be coupled to the pack tray 21. For example, the pack cover 22 and the pack tray 21 may be configured to be coupled to each other by a method such as bolting, adhesion, snap fitting, or welding.

[0120] Meanwhile, since the cell assembly 100 is configured in a form in which the first pouch-type battery cell 110A and the second pouch-type battery cell 110B are connected in series, voltage sensing is required at the point where the first pouch-type battery cell 110A and the second pouch-type battery cell 110B are connected in series. Therefore, the battery pack of the present invention includes a voltage sensing unit 30 connected to the bus bar 123 of the bridge bus bar unit 120 of each cell assembly 100 for voltage sensing at the point where the first pouch-type battery cell 110A and the second pouch-type battery cell 110B are connected in series.

[0121] Specifically, referring to Figures 14 to 16, the voltage sensing unit 30 extends in a first direction and is inserted into a valley formed by aligning the upper notches 135 of the cell assembly groups described above at the top of the first cell assembly group 10A and the second cell assembly group 10B, and is configured to be electrically connected to the bus bar 123 provided on the bridge bus bar unit 120 of each of the cell assembly groups 10.

[0122] The voltage sensing unit 30 may include a sensing frame 31 and a sensing circuit board 32 as shown in Fig. 14. The sensing frame 31 is made of an insulating material and may be inserted into the upper notch 135 of the cell assembly 100 of Fig. 11. The sensing frame 31 also includes sensing holes 31a formed by drilling in the areas where the bridge bus bar units 120 of each cell assembly 100 are located as shown in Figs. 15 and 16. The bent upper end 123a of the bus bar 123 is located below the sensing holes 31a.

[0123] The sensing circuit board 32 may be implemented as a rigid circuit board or a planar flexible printed circuit board that may be disposed on the upper portion of the sensing frame 31, and may include sensing terminals that are inserted into the sensing holes 31a.

[0124] According to the above configuration, as shown in FIG. 16, the sensing terminal can pass through the sensing hole 31a to contact and be electrically connected to the bus bar 123 of the bridge bus bar unit 120, in other words, the bent upper end 123a of the bus bar 123.

[0125] The voltage sensing unit 30 may be connected to the battery control system 60 via a signal transmission member (not shown) such as a cable connector or a flexible printed circuit board (FPC) and configured to transmit and receive data to and from the BMS via the signal transmission member.

[0126] The cross beams include a first cross beam 40, a second cross beam 50, and a third cross beam 24. As mentioned above, the cross beams are components that provide mechanical rigidity for the pack tray 21.

[0127] 13, the first cross beam 40 may be provided on the pack tray 21 in a form extending in a second direction (X-axis direction) intersecting the first direction (Y-axis direction) between the first cell assembly group 10A and the second cell assembly group 10B. Although the first cross beam 40 is shown separated from a bottom plate 21B of the pack tray 21 in the drawing, the first cross beam 40 may be provided integrally with the pack tray 21.

[0128] In addition, the first cross beam 40 may have a similar height to the bus bar housing 121 of the bridge bus bar unit 120, and a lower end portion of the center along the longitudinal direction (X-axis direction) may be recessed upward.

[0129] The second cross beam 50 may be configured to be located on the upper portion of the voltage sensing unit 30, extend in the first direction, and be fixedly coupled to both side panels in the ±Y-axis directions of the pack tray 21. Also, as shown in FIG 12, the second cross beam 50 may be configured to be inserted into an upper notch 135 of the cell assembly 100.

[0130] The third cross beam 24 extends in the second direction from the bottom plate 21B of the pack tray 21 as shown in FIG. 13, and both ends are fixed to and connected to both side plates in the ±Y-axis directions. Due to the cross beam mounting structure, the second cross beam 50 is smaller in size than the first cross beam 40, so that the supporting force of the second cross beam 50 on the pack tray 21 may be relatively weak. The third cross beam 24 may play a role in reinforcing the second cross beam 50, which has a relatively weak supporting force on the pack tray 21. As described above, the cell assembly 100 includes the lower notch 136. Therefore, even if the third cross beam 24 is present on the bottom plate 21B of the pack tray 21, the cell assembly group 10 can be easily placed on the bottom plate 21B of the pack tray 21 without being interfered with by the third cross beam 24.

[0131] Meanwhile, the battery control system 60 included in the battery pack according to an embodiment of the present invention may be provided in a space separated from the cell assembly group 10 by a partition wall 23. The battery control system 60 may include a BMS (Battery Management System) and a BDU (Battery Disconnect Unit). The BMS may be configured to control the charge / discharge state, power state, and performance state of the pouch-type battery cells 110. The BDU controls the electrical connection of the battery cells to manage the power capacity and functions of the battery pack 1. For this purpose, the BDU may include a power relay, a current sensor, a fuse, and the like.

[0132] As described above, the above-described battery pack 1 according to the present invention can accommodate a large number of pouch-type battery cells 110 with large capacity inside the pack case 20 by making maximum use of the internal space of the pack case 20.

[0133] For example, in the case of the conventional battery pack 1 of Fig. 1, the configuration of the module case for configuring the battery modules, the gaps between each battery module and the cross beam, the complex layout of the cables for electrically connecting the battery modules arranged in a lattice structure, etc. act as negative factors in increasing the energy capacity of the battery pack 1. However, the battery pack 1 of the present invention does not have such negative factors.

[0134] Therefore, according to the configuration of the present invention, the pouch-type battery cells 110 can be housed inside the pack case 20 with significantly high spatial efficiency, making it possible to provide a battery pack 1 with improved energy capacity.

[0135] FIG. 17 is an exploded perspective view of the main components of a cell assembly 400 according to another embodiment of the present invention, FIG. 18 is a perspective view of a cell assembly 400 according to another embodiment of the present invention, FIG. 19 is a top view of the central region of the cell assembly 400 of FIG. 18, and FIG. 20 is a bottom view of the central region of the cell assembly 400 of FIG. 18.

[0136] Next, a cell assembly 400 according to another embodiment of the present invention will be described with reference to Figures 17 to 20. The same reference numerals as those in the above-mentioned embodiment indicate the same members, and duplicated descriptions of the same members will be omitted. The following description will focus on the differences from the above-mentioned embodiment.

[0137] A cell assembly 400 according to another embodiment of the present invention is different from the above-described cell assembly 100 in the configuration of the cell cover and the assembly structure of the cell cover and the cell unit, but other configurations are substantially the same.

[0138] The cell assembly 400 according to another embodiment of the present invention includes a cell cover 430 that partially surrounds a cell unit composed of a first pouch-type battery cell 110A, a bridge bus bar unit 120, and a second pouch-type battery cell 110B arranged in a row. In particular, the cell cover 430 may be configured to surround the upper and both sides of the cell unit but not the lower part, so that the lower edge portions E2 of the first pouch-type battery cell and the second pouch-type battery cell are exposed to the outside.

[0139] In other words, while the cell cover 130 of the above-mentioned embodiment has a vertical cross section that is approximately U-shaped to expose the upper edge portions E1 of the first pouch-type battery cell 110A and the second pouch-type battery cell 110B, the cell cover 430 of another embodiment of the present invention has a vertical cross section that is approximately n-shaped to expose the lower edge portions E2 of the first pouch-type battery cell and the second pouch-type battery cell.

[0140] More specifically, referring to FIGS. 17 and 18, the cell cover 430 may include an upper end cover portion 431, a first side cover portion 432 and a second side cover portion 433.

[0141] Here, the upper cover part 431 may be configured to surround an upper portion of the upper edge part E1 of the pouch-type battery cell 110 housed therein. In particular, the upper cover part 431 may be configured in a form in which it is in contact with or spaced apart from the upper edge part E1 of the pouch-type battery cell 110. Also, the upper cover part 431 may be configured in a planar form. In this case, the cross section of the upper cover part 431 may be formed in a horizontal straight line shape, and may surround the upper edge part E1 of the pouch-type battery cell 110 from the outside in a straight line shape.

[0142] The first side cover part 432 may be configured to extend downward from one end of the upper cover part 431. For example, the first side cover part 432 may be configured to extend downward (in the -Z axis direction in the drawing) from the left end part of the upper cover part 431. Furthermore, the first side cover part 432 may be formed in a flat shape. In this case, the first side cover part 432 may be configured by being bent from the upper cover part 431.

[0143] The first side cover part 432 may be configured to surround the outside of one side housing part R of the first pouch-type battery cell 110A and the second pouch-type battery cell 110B housed therein.

[0144] The second side cover part 433 may be positioned at a distance from the first side cover part 432 in the horizontal direction. The second side cover part 433 may be configured to extend downward from the other end of the upper end cover part 431. For example, the second side cover part 433 may be configured to extend downward from a right end part of the upper end cover part 431. The second side cover part 433 may also be configured in a planar shape like the first side cover part 432. In this case, it can be said that the second side cover part 433 and the first side cover part 432 are arranged parallel to each other while being horizontally spaced apart from each other.

[0145] The second side cover part 433 may be configured to surround the outside of the other side of the storage part R of the pouch-type battery cell 110 housed therein. In the above embodiment, the cell cover 430 may have an internal space defined by the top cover part 431, the first side cover part 432, and the second side cover part 433. The cell cover 430 may house one or more pouch-type battery cells 110 in the internal space defined in this manner.

[0146] In addition, the cross-sectional areas of the first side cover part 432 and the second side cover part 433 are larger than the cross-sectional area of ​​the pouch-type battery cell 110 that the first side cover part 432 and the second side cover part 433 face, thereby preventing the storage part R from being exposed to the outside and ensuring maximum safety.

[0147] In particular, the pouch-type battery cell 110 may include a sealed portion and an unsealed portion as the edge portions E1 to E4. For example, in the embodiment of FIG. 17, the upper edge portion E1 may be a sealed portion of the pouch-type battery cell 110, which is a DSF (Double Side Folding) portion, and the lower edge portion E2 may be an unsealed portion of the pouch-type battery cell 110.

[0148] The cell cover 430 may be configured to surround the pouch-type battery cell 110, but to surround at least a part of the sealed part of the edge parts E1 to E4, and to expose at least a part of the unsealed part to the outside. For example, referring to the embodiment of FIG. 17, the cell cover 430 may be configured to surround the upper edge part E1, which is a part of the sealed part of the pouch-type battery cell 110. In this case, the pouch-type battery cell 110 accommodated inside the cell cover 430 is configured such that the upper edge part E1, which is the sealed part, faces the upper end cover part 431. In addition, the cell cover 430 may surround the pouch-type battery cell 110 such that the lower edge part E2, which is the unsealed part of the pouch-type battery cell 110, is exposed to the outside. In this case, the lower edge part E2, which is the unsealed part of the pouch-type battery cell 110, may be disposed on the open surface of the cell cover 430.

[0149] For reference, in the pouch-type battery cell 110, the upper edge portion E1 as a sealed portion may be relatively more vulnerable to the discharge of high-temperature gas or flame than the lower edge portion E2 as an unsealed portion. However, according to the embodiment, when the upper edge portion E1 as a sealed portion is disposed to face the upper end cover portion 431 and venting gas is discharged from the sealed portion, it may be more advantageous in directional venting that prevents the venting gas from moving upward and induces horizontal and / or downward movement.

[0150] In addition, in the pouch-type battery cell 110, the lower edge portion E2 as the unsealed portion has a relatively larger cross-sectional area and a flatter shape than the upper edge portion E1 as the sealed portion, is disposed on the open surface of the cell cover 430, and is in direct contact with the thermal resin G1 described later, thereby increasing the cooling efficiency.

[0151] Also, the cell cover 430 according to another embodiment of the present invention includes notches 435 and 436 partially cut inward at at least one of the upper and lower ends where the bridge bus bar unit 120 is housed.

[0152] For example, as shown by the circle in FIG. 17, the cell cover 430 may have an upper notch 435 and a lower notch 436 at two locations, the upper end and the lower end, in the center.

[0153] 19 and 20, in the bridge bus bar unit 120, the bus bar housing 121 is configured so that an upper surface portion thereof is lower in height than the upper edge portion E1 of the first pouch-type battery cell 110A and the second pouch-type battery cell 110B, and thus does not protrude above the upper notch 435 when housed in the cell cover 430, and a lower surface portion of the bus bar housing 121 does not protrude below the lower notch 436. Therefore, the cell assembly 400 according to this embodiment may be provided in such a manner that a central region where the bridge bus bar unit 120 is located is recessed inward.

[0154] 19, the upper notch 435 of the cell cover 430 of the present embodiment may be configured to expose only the bent upper end 123a of the bus bar 123 upward, and to block the first pouch-type battery cell 110A side (-X direction) and the second pouch-type battery cell 110B side (+X direction) by screen plates 435a, 435b. Here, the screen plates 435a, 435b may be configured to be coupled by having their lower ends inserted into the upper surface of the bus bar housing 121.

[0155] According to this configuration, the internal space of the cell cover 430 is physically separated into a left space and a right space with the bridge bus bar unit 120 at the center, so that airtightness can be increased. Therefore, when assembling a battery pack using the cell assembly 400, the cell assembly 400 may be disposed so that the open surface of the cell cover 430 faces the bottom plate 21B of the pack tray 21, thereby shielding the open surface of the cell cover 430. In this case, in a situation where a thermal event occurs, the movement of ignition sources such as gas, heat, sparks, etc. between the first pouch-type battery cell 110A and the second pouch-type battery cell 110B housed in the cell cover 430 is restricted, so that the propagation of thermal runaway between the first pouch-type battery cell 110A and the second pouch-type battery cell 110B can be blocked or delayed.

[0156] Meanwhile, a cell assembly group 11 as shown in Figures 21 and 22 may be formed by stacking a plurality of cell assemblies 400 according to another embodiment of the present invention in one direction. In this case, in the cell assembly group 11, the upper notch 435 and the lower notch 436 may be aligned in one direction (±Y direction) to form a valley shape. The space secured in the cell assembly 400 by the valley shape configuration may be used as an installation space for the voltage sensing unit 30, the second cross beam 50, and the third cross beam 24 when assembling the battery pack 2 as shown in Figures 23 and 24.

[0157] The plurality of cell assembly groups 11 can be said to be an assembly of the above-mentioned cell assemblies 400, and can be housed inside a pack case 20, for example, as shown in Figures 23 and 24. In this embodiment, the plurality of cell assembly groups 11 can be divided into a first cell assembly group 11A and a second cell assembly group 11B. The reason why the plurality of cell assembly groups 11 are divided into the first cell assembly group 11A and the second cell assembly group 11B is to conveniently distinguish between those located in the +Y-axis direction and those located in the -Y-axis direction based on the first cross beam 40 of the pack tray 21 in Figures 23 and 24.

[0158] FIG. 25 is a diagram illustrating a cooling configuration of a battery pack 2 according to another embodiment of the present invention.

[0159] The pack case 20 of the battery pack according to another embodiment of the present invention may be configured to include a heat sink. Here, a heat sink refers to an object that absorbs heat from another object through direct or indirect thermal contact and dissipates it. The pack case 20 may function as a heat sink itself, or may be configured to include a heat sink having a flow path F1 inside or outside so that cooling water can flow therethrough.

[0160] In this embodiment, the heat sink includes an upper heat sink 520 and a lower heat sink 510, and the upper heat sink 520 may be provided on the pack cover 22, and the lower heat sink 510 may be provided on the pack tray 21, as shown in FIG.

[0161] The cell cover 430 may be configured to be placed on the bottom plate 21B of the pack tray 21 in a state in which the lower ends of the first side cover part 432 and the second side cover part 433 are sandwiched and coupled by the lower heat sink 510. For example, as shown by "K1" in Fig. 25, the lower end part of each cell cover 430 may be fastened and fixed by being partially sandwiched by the lower heat sink 510, and the upper heat sink 520 and the upper end cover part 431 of the cell cover 430 may be disposed to face each other.

[0162] Thermal resins G1 and G2 may be provided on the lower edge portion E2 and the upper edge portion E1 of the pouch-type battery cell 110 inside the cell cover 430. Thermal resin G3 may also be provided between the upper end cover portion 431 and the upper heat sink 520 outside the cell cover 430.

[0163] According to the above configuration, as shown by "H1" in Fig. 25, heat generated in each cell assembly 400 is not only dissipated from the lower edge E2 of the pouch-type battery cell 110 to the thermal resin (G1) to the lower heat sink 510, but also from the upper edge E1 of the pouch-type battery cell 110 to the thermal resin G2 to the upper cover part 431 of the cell cover 430 to the thermal resin G3 to the upper heat sink 520 as shown by "H2" in Fig. 25. In this way, the battery pack of the present invention is capable of dual cooling in which heat from the pouch-type battery cell 110 is transferred to the lower heat sink 510 and the upper heat sink 520 for cooling. In particular, compared to a battery pack including a conventional battery module, the battery pack of the present invention has a configuration in which the lower edge portion E2 of the pouch-type battery cell directly faces the lower heat sink 510 and the cell cover 430 is attached to the lower heat sink 510. Therefore, there is no thermal contact resistance element (such as the module case of a battery module) between the heat sink in the pouch-type battery cell, and the heat conduction distance is also short, so that the cooling performance can be further improved.

[0164] In addition, since the cell cover 430, the pouch-type battery cells 110 inside the cell cover 430, and the pack case 20 are fixed to each other by the thermal resins G1, G2, and G3, the cell assembly 400 can be stably assembled and fixed to the pack case 20 without using fastening parts such as bolts, rivets, etc.

[0165] FIG. 26 is a diagram showing a modified example of a cell cover in a battery pack according to another embodiment of the present invention, and FIG. 27 is a diagram showing a modified example of a pack tray in a battery pack according to another embodiment of the present invention.

[0166] 26 and 27 are perspective views each showing a schematic configuration of a cell cover 600 and a pack tray 21 according to another embodiment of the present invention. Detailed descriptions of parts that are the same or similar to the above-mentioned embodiment will be omitted, and differences will be mainly described.

[0167] The cell cover 600 according to the modified example includes an upper end cover part 631, a first side cover part 632, a second side cover part 633, an upper notch 635, and a lower notch 636, similar to the above-mentioned embodiment. Furthermore, the cell cover 600 further includes a protrusion 601 at a lower end of at least one of the first side cover part 632 and the second side cover part 633, as shown in Fig. 26. The protrusion 601 may be provided in a form that extends downward from the lower end of the cell cover 600 by a relatively long distance.

[0168] 26, a plurality of, for example, six, protrusions 601 may be provided at the lower end of the first side cover part 632 and / or the second side cover part 633 along the longitudinal direction of the cell cover 600.

[0169] In an embodiment in which the cell cover 600 of this type is provided, the pack tray 21 may be formed with a coupling groove 21Ba configured to allow the protrusion 601 to be inserted therein, as shown in FIG. 27. Here, the coupling groove 21Ba may be provided at a position and in a shape corresponding to the protrusion 601. For example, referring to the embodiment of FIG. 27, the bottom plate 21B of the pack tray to which the cell cover 600 is attached may be provided with a coupling groove 21Ba at a position and in a shape corresponding to the protrusion 601 of the cell cover 600. Furthermore, one or more protrusions 601 may be inserted into one coupling groove 21Ba. For example, two protrusions 601 may be inserted into the coupling groove 21Ba in the center portion such as the portion indicated by "K1" in FIG. 25. Meanwhile, one protrusion 601 may be inserted into the coupling groove 21Ba located at the outermost position in the stacking direction of the cell cover 600 in the pack tray 21. For example, in the configuration of FIG. 27, one protrusion 601 can be inserted into each of the leftmost and rightmost coupling grooves 21Ba among the multiple coupling grooves 21Ba arranged in the left-right direction.

[0170] According to this embodiment of the present invention, the connection between the cell cover 600 and the pack tray 21 can be further improved. As a result, even in a situation where vibration or impact is applied to the battery pack or swelling occurs in the pouch-type battery cell 110, the stacked state of the cell cover 600 and the pouch-type battery cell 110 accommodated therein can be stably maintained. Furthermore, according to the embodiment, the movement of the cell cover 600 in the front-rear direction (X direction) can be prevented. Also, according to the embodiment, the movement of the cell cover 600 in the left-right direction (Y axis direction) can be prevented, and the gap between the first side cover part 632 and the second side cover part 633 can be effectively prevented from opening.

[0171] FIG. 28 is a bottom view of one end region of a cell assembly group in a battery pack according to another embodiment of the present invention, and FIG. 29 is a schematic diagram showing the gas venting configuration of a battery pack according to another embodiment of the present invention.

[0172] Next, a directional venting configuration for gas or flame / spark upon occurrence of a thermal event in a battery pack according to another embodiment of the present invention will be described with reference to FIGS. 28 and 29. FIG.

[0173] The cell assembly 400 according to this embodiment has a directional venting space VS inside the cell cover 430. The directional venting space VS may be provided at one or both ends of the cell cover 430 in the longitudinal direction.

[0174] In the case of the pouch-type battery cell 110, the sealing portion from which the electrode lead 111 is drawn, i.e., the front edge portion E3 or the rear edge portion E4, is relatively thinner than the receiving portion R, so that there is an excess space in the front portion (rear portion) of the cell cover surrounding the front edge portion E3 or the rear edge portion E4. Such excess space inside the cell cover may be used as a directional venting space VS. As shown in FIG. 28, the cell cover 430 of each cell assembly 400 may be partially sandwiched and coupled to the outer bus bar housing 201 so that the directional venting space VS is left, as indicated by "D1" in the drawing. In this case, the directional venting space VS may have a structure that is closed except in one direction.

[0175] Meanwhile, as described above, in the cell assembly 400 according to the present embodiment, thermal resins G1, G2, and G3 are applied to the upper edge portion E1 and the lower edge portion E2 of the pouch-type battery cell 110 in order to cool and fix the pouch-type battery cell 110. In this case, as shown in Fig. 28, the thermal resin G1 applied to the open surface side of the cell cover 430 is applied up to just before the directional venting space VS. That is, in the cell assembly 400 according to the present embodiment, the thermal resins G1, G2, and G3 are applied only to the upper and / or lower portions of the receiving portion R of the pouch-type battery cell 110, and the thermal resin G1 is not applied to the front edge portion E3 and / or rear edge portion E4 areas, which are sealing portions where the electrode leads 111 are drawn out.

[0176] Therefore, the directional venting space VS according to this embodiment is blocked at its upper side (Z direction) by the upper end cover part 431 of the cell cover 430, and its front, rear, left and right directions (±X, ±Y directions) are blocked by at least one of the outer bus bar housing 201, the storage part R for the pouch-type battery cell 110, and the first side cover part 432 and the second side cover part 433 of the cell cover 430. Meanwhile, the lower side (-Z direction) of the directional venting space VS may be connected to the outside.

[0177] According to this configuration, when a thermal event occurs and gas or flame / spark (such as metal pieces detached from the electrode assembly) is ejected from the pouch-type battery cell 110, the upward movement of the gas or flame / spark can be prevented by the upper end cover part 431 of the cell cover 430. In addition, the outer bus bar housing 201 and the first and second side cover parts 432 and 433 of the cell cover 430 can prevent the gas or flame / spark from moving in the front, back, left and right directions. Therefore, as shown in FIG. 29, the flow of the gas or flame / spark is guided downward from the directional venting space VS.

[0178] Also, the pack case 20 may include a gas exhaust port 25 communicating with the directional venting space VS. For example, the gas exhaust port 25 may be provided in the bottom plate 21B of the pack tray 21, which corresponds to the vertical lower part of the directional venting space VS. A rupture disk 27 that ruptures due to a predetermined pressure or heat may be attached to the gas exhaust port 25. The rupture disk 27 is made of a material that burns out due to gas pressure or at a certain temperature or higher, and may be made of, for example, a thin aluminum film structure or a plastic resin structure. For reference, in this embodiment, the gas exhaust port 25 is configured to penetrate the bottom plate 21B of the pack tray 21 in the vertical direction, but unlike this embodiment, the gas exhaust port 25 may be configured in the form of a channel provided inside the pack tray 21, and the channel may be configured to connect to one side opening (not shown) of the pack case 20.

[0179] Due to the directional venting structure of the cell assembly and the pack case structure, when gas is generated in a specific cell assembly 400 included in the battery pack, the gas in the cell assembly 400 does not propagate to other adjacent cell assemblies 400, but can be discharged below the pack tray 21 in which the cell assembly 400 is located. Therefore, the battery pack according to the present invention has an effect of suppressing or significantly delaying radio waves of thermal runaway of the pouch-type battery cells 110 in the event of a thermal event.

[0180] As described above, according to the present invention, it is possible to provide a cell assembly embodied in the form of a long cell in which one or more pouch-type battery cells are connected to one or more other pouch-type battery cells in a longitudinal direction using a bridge bus bar unit. In addition, by directly assembling the pouch-type battery cells into a pack case of a battery pack using such a cell assembly, it is possible to maximize the space utilization rate of the battery pack and significantly improve the energy capacity.

[0181] In addition, according to one embodiment of the present invention, the cooling efficiency of the battery pack can be improved, and the safety of the battery pack can be improved by controlling the exhaust direction of gas, flames, etc. exhausted from the pouch-type battery cell.

[0182] Meanwhile, the battery pack according to the present invention can be used as a power energy source for an automobile. That is, an automobile (not shown) according to the present invention may include the battery pack 1 according to the present invention described above. Here, the automobile (not shown) according to the present invention may include a certain automobile (not shown) that uses electricity as a driving source, such as an electric automobile or a hybrid automobile. Furthermore, the automobile according to the present invention may further include various other components included in the automobile, such as a body and a motor, in addition to the battery pack according to the present invention.

[0183] In addition, although terms indicating directions such as up, down, left, right, front, and back are used in this specification, it will be obvious to those skilled in the art that these terms indicate relative positions and are used only for convenience of explanation, and may change depending on the position of the target object, the position of the observer, etc.

[0184] Although the present invention has been described above with reference to limited embodiments and drawings, it goes without saying that the present invention is not limited thereto, and various modifications and variations can be made by those having ordinary skill in the art to which the present invention pertains within the scope of the technical spirit of the present invention and the scope of the claims. [Explanation of symbols]

[0185] 10 Cell Assembly Group 10A First Cell Assembly Group 10B Second Cell Assembly Group 11 Cell Assembly Group 11A Cell Assembly Group 1 11B Cell Assembly Group 2 20 pack case 21 Pack Tray 22 Pack Cover 23 Bulkhead 24 3rd Cross Beam 25 Gas exhaust port 27 Bursting Disc 30 Voltage Sensing Unit 31 Sensing Frame 31a Sensing Hole 32 Sensing circuit board 40 First Cross Beam 50 2nd Cross Beam 60 Battery Control System 100 Cell Assembly 110 Pouch type battery cell 110A No.1 pouch type battery cell 110B Second Pouch Type Battery Cell 111 Electrode lead 111A Positive Lead 111B Negative lead 120 Bridge busbar unit 121 Busbar housing 121a Insertion port 121b Slot 121c opening 121d Receiving part 121e Recess 123 Busbar 130 Cell Cover 131 Lower end cover part 132 First side cover part 133 Second side cover part 135 Upper notch 136 Lower notch 200 Front busbar unit 201 Outer busbar housing 300 Rear busbar unit 400 Cell Assembly 430 Cell Cover 431 Top cover part 432 First side cover part 433 Second side cover part 435 Upper notch 436 Lower notch 510 Lower Heatsink 520 Upper Heatsink 600 Cell Cover 601 Protrusion 631 Top cover part 632 First side cover part 633 Second side cover part 635 Upper notch 636 Lower notch

Claims

1. A plurality of cell banks each including one or more stacked pouch-type battery cells arranged in a row with each other; a bridge bus bar unit disposed between the cell banks and electrically connecting the cell banks to each other; a cell cover that partially surrounds and supports a cell unit including the plurality of cell banks and the bridge bus bar unit, The cell cover has a notch that is partially recessed inward at at least one of an upper portion and a lower portion of a central region where the bridge bus bar unit is located.

2. The plurality of cell banks include one or more first pouch-type battery cells forming a cell bank; 2. The cell assembly according to claim 1, further comprising: one or more second pouch-type battery cells that form another cell bank and are arranged in a row with the first pouch-type battery cell along the longitudinal direction of the first pouch-type battery cell.

3. The cell assembly according to claim 2 , wherein the cell cover is configured to support the first pouch-type battery cell and the second pouch-type battery cell in an upright state.

4. 4. The cell assembly according to claim 2, wherein the cell cover partially surrounds the first pouch-type battery cell and the second pouch-type battery cell such that upper or lower portions of the first pouch-type battery cell and the second pouch-type battery cell are exposed.

5. The first pouch-type battery cell and the second pouch-type battery cell each include a receiving portion in which an electrode assembly is received and an edge portion around the receiving portion, 4. The cell assembly according to claim 2, wherein the cell cover is provided to surround one of upper edge portions and lower edge portions of the first pouch-type battery cell and the second pouch-type battery cell, and the receiving portion.

6. The cell cover is a lower end cover part configured to surround lower ends of lower edge parts of the first pouch-type battery cell and the second pouch-type battery cell; a first side cover part extending upward from one end of the lower end cover part and surrounding an outside of one side receiving part of the first pouch-type battery cell and the second pouch-type battery cell; a second side cover part extending upward from the other end of the lower end cover part at a position spaced apart from the first side cover part and surrounding an outside of the other side housing portion of the first pouch-type battery cell and the second pouch-type battery cell.

7. The cell cover is an upper end cover part configured to surround upper ends of upper edge parts of the first pouch-type battery cell and the second pouch-type battery cell; a first side cover part extending downward from one end of the upper cover part and surrounding an outer side of one side receiving part of the first pouch-type battery cell and the second pouch-type battery cell; a second side cover part extending downward from the other end of the upper cover part at a position spaced apart from the first side cover part and surrounding an outside of the other side housing portion of the first pouch-type battery cell and the second pouch-type battery cell.

8. The first pouch-type battery cell and the second pouch-type battery cell include a sealed portion and an unsealed portion as the edge portion, 6. The cell assembly according to claim 5, wherein the cell cover is configured to enclose at least a portion of the sealed portion of the first pouch-type battery cell and the second pouch-type battery cell, and the unsealed portion is exposed.

9. The cell cover is 4. The cell assembly according to claim 2, wherein the first pouch-type battery cell, the bridge bus bar unit, and the second pouch-type battery cell are arranged in a row in this order to have a length corresponding to the length of the first pouch-type battery cell, the bridge bus bar unit, and the second pouch-type battery cell.

10. 4. The cell assembly according to claim 2, wherein the first pouch-type battery cell and the second pouch-type battery cell are bidirectional pouch-type battery cells having electrode leads protruding in both directions.

11. The first pouch-type battery cell has an electrode lead of a first polarity connected to the bridge bus bar unit; The cell assembly according to claim 2 or 3, wherein the second pouch-type battery cell has an electrode lead of a second polarity connected to the bridge bus bar unit.

12. The bridge bus bar unit includes: A busbar housing made of an electrically insulating material and having a hollow tubular shape; a bus bar that is partially inserted into the bus bar housing and is made of a conductive material; 4. The cell assembly according to claim 2, wherein an electrode lead of the first pouch-type battery cell and an electrode lead of the second pouch-type battery cell are in contact with and fixed to one side and the other side of the bus bar, respectively, inside the bus bar housing.

13. The bus bar housing includes: one or more slots provided on one side surface and the opposite side surface to each other for inserting electrode leads of the first pouch-type battery cell or the second pouch-type battery cell; The cell assembly according to claim 12 , further comprising: an insertion opening provided on an upper surface thereof so that the bus bar can be inserted in a vertical direction.

14. The bus bar housing includes:

14. The cell assembly of claim 13, further comprising openings in the non-slotted side for welding.

15. The cell assembly according to claim 13 , wherein the bus bar has a bent upper end portion, the bent upper end portion being configured to be exposed to an outside of the insertion opening.

16. 13. The cell assembly according to claim 12, wherein an upper surface of the bus bar housing is positioned at a height lower than upper ends of the first pouch-type battery cell and the second pouch-type battery cell.

17. a cell assembly group including a plurality of cell assemblies according to claim 1 stacked in a first direction; a pack case including a pack tray on which the cell assembly group is placed and a pack cover which is connected to the pack tray to cover the cell assembly group; a voltage sensing unit extending in the first direction, disposed on an upper portion of the cell assembly group, and electrically connected to a bus bar provided in the bridge bus bar unit of each of the cell assembly groups.

18. The battery pack according to claim 17 , wherein the cell assemblies are attached to an upper surface of the pack tray by adhesive.

19. The voltage sensing unit includes: an insulating material and disposed on top of the bridge busbar unit; a sensing frame including sensing holes formed by drilling in each area where each of the bridge bus bar units is located; a sensing circuit board disposed on the upper portion of the sensing frame; The battery pack according to claim 17, wherein the sensing terminals of the sensing circuit board pass through the sensing holes and are electrically connected to the bus bars of the bridge bus bar unit.

20. The cell assembly group includes a first cell assembly group and a second cell assembly group, 18. The battery pack of claim 17, further comprising: a first cross beam extending in a second direction intersecting the first direction between the first cell assembly group and the second cell assembly group and fixedly coupled to the pack tray.

21. 18. The battery pack as claimed in claim 17, further comprising: a second cross beam located above the voltage sensing unit, extending in the first direction, and fixedly coupled to the pack tray.

22. The plurality of cell banks include one or more first pouch-type battery cells forming a cell bank; and one or more second pouch-type battery cells that form another cell bank and are arranged in a row with the first pouch-type battery cell along a longitudinal direction of the first pouch-type battery cell; the pack case includes a heat sink; The battery pack according to claim 17, wherein a thermal resin is provided between the first pouch-type battery cell and the heat sink, and between the second pouch-type battery cell and the heat sink.

23. The battery pack of claim 22, wherein the heat sink comprises an upper heat sink and a lower heat sink disposed at an upper portion and a lower portion of the cell cover, respectively.

24. The battery pack according to claim 17, wherein at least one end of the cell cover is configured to be sandwiched and coupled to the pack case.

25. The cell assembly comprises: The battery pack according to claim 17, wherein a directional venting space through which gas can move from at least one end in a longitudinal direction to an upper portion or a lower portion of the cell cover is provided inside the cell cover.

26. The battery pack according to claim 25, wherein the pack case comprises a gas exhaust port communicating with the directional venting space.

27. 27. The battery pack of claim 26, further comprising a burst disk attached to the gas exhaust port, the burst disk being configured to burst under a predetermined pressure or heat.

28. 20. A motor vehicle comprising the battery pack of claim 17.

Images