Battery pack and automobile including same

Abstract

A battery pack and a vehicle including the same are disclosed. The battery pack according to an embodiment of the present invention includes a battery assembly including a plurality of cell units, and a pack case that houses the battery assembly in an internal space, where each cell unit includes at least one battery cell and a cell cover that at least partially encloses an exterior of the at least one battery cell, and a vent space is provided between the cell cover and the battery cell.

Description

[Technical field]

[0001] The present invention relates to a battery pack and a vehicle, and more particularly to a battery pack manufactured by a cell-to-pack (CTP) method and a vehicle including the same. This application claims priority based on Korean Patent Application No. 10-2022-0089911 filed on July 20, 2022, Korean Patent Application No. 10-2022-0089941 filed on March 7, 2023, and Korean Patent Application No. 10-2023-0030192 filed on March 7, 2023, the entire contents of which are incorporated herein by reference in their entirety. [Background technology]

[0002] Generally, a secondary battery refers to a battery that can be repeatedly charged and discharged, such as a lithium-ion battery, a lithium polymer battery, a nickel-cadmium battery, a nickel-metal hydride battery, a nickel-zinc battery, etc. The output voltage of a battery cell, which corresponds to the basic unit of charging and discharging such a secondary battery, is about 2.5V to 4.2V.

[0003] In recent years, secondary batteries have come to be applied to devices that require a high output voltage and a large charging capacity, such as electric vehicles and energy storage systems (ESS). A battery module is formed by connecting a plurality of battery cells in series or parallel, and a battery pack is manufactured by connecting a number of such battery modules again in series or parallel, and the battery pack is widely used.

[0004] However, as disclosed in Korean Patent Publication No. 10-2379227 and Korean Patent Publication No. 10-2022-0052183, etc., in conventional technologies, battery cells are housed in a box-shaped metal case to form a battery module, and these battery modules are then housed again in a battery pack case to manufacture a battery pack, which results in problems such as an increase in the weight and volume of the entire battery pack and a decrease in the energy density of the battery pack.

[0005] In addition, if the conventional cell-to-pack method, in which multiple battery cells are directly attached to a pack case of a battery pack in order to increase the energy density of the battery pack, is applied to a pouch-type battery cell having a soft case, it is difficult to handle or stack multiple battery cells at the same time, and there is a risk of the battery cells being damaged in the process of attaching them to the pack case.

[0006] In recent years, the demand for battery packs for electric vehicles has been increasing. These battery packs are equipped with multiple battery cells, and stricter safety management is required. If thermal runaway, fire, explosion, etc. occurs in some cells in a certain battery module, the generated high-temperature gas, flame, or high-temperature internal material may be ejected and propagated to other adjacent battery modules, causing secondary thermal runaway, secondary fire, explosion, etc., which may cause cells in multiple battery modules to thermally runaway, ignite, or explode in a chain reaction. Therefore, there is a great need for a means to suppress or delay flame propagation between battery modules when a thermal event such as thermal runaway occurs. However, conventional battery packs may be vulnerable to thermal events. In particular, when a thermal event occurs inside a battery pack, thermal runaway occurs, a flame occurs, and in severe cases, an explosion may occur, and improvements are required. Summary of the Invention [Problem to be solved by the invention]

[0007] The technical problem to be solved by the present invention is to provide a battery pack and an automobile including the same, which reduce the overall weight and volume of the battery pack and increase the energy density of the battery pack.

[0008] Another technical problem to be solved by the present invention is to provide a battery pack and a vehicle including the same, which facilitates handling and installation of battery cells and prevents damage to the battery cells during a manufacturing process of a battery pack including a plurality of battery cells, and which reduces manufacturing costs by simplifying and reducing the weight of structures required for installing the battery cells.

[0009] Furthermore, another technical problem to be solved by the present invention is to provide a battery pack and a vehicle including the same that can ensure excellent safety when a thermal event occurs.

[0010] However, the technical problems that the present invention aims to solve are not limited to those mentioned above, and other problems not mentioned will be clearly understood by those skilled in the art from the detailed description of the invention described below. [Means for solving the problem]

[0011] A battery pack according to one embodiment of the present invention includes a battery assembly including a plurality of cell units, and a pack case that houses the battery assembly in an internal space, each cell unit including at least one battery cell and a cell cover that at least partially encloses an exterior of the at least one battery cell, and a vent space may be provided between the cell cover and the battery cell.

[0012] In one embodiment, the at least one battery cell may include a pouch-type battery cell.

[0013] In one embodiment, the cell cover may be configured to support the at least one battery cell in an upright position.

[0014] The cell cover may partially encase the battery cell to form an opening where at least one side of the encased battery cell is exposed toward the pack case.

[0015] In one embodiment, the cell cover may be constructed in one piece.

[0016] The cell cover may be formed from a single bent plate.

[0017] The cell cover may include an insulating coating layer on an inner surface.

[0018] The insulating coating layer may be formed by coating, applying or attaching any one of insulating materials selected from the group consisting of silicone resin, polyamide and rubber.

[0019] In one embodiment, the cell cover may be constructed of a material including stainless steel (SUS).

[0020] Furthermore, the battery pack of the present invention may further include a control module housed in the internal space of the pack case and configured to control charging and discharging of the battery cells.

[0021] In one embodiment, the cell cover may include a first cover portion covering one side of the at least one battery cell, a second cover portion covering the other side of the at least one battery cell, and a third cover portion connecting the first cover portion and the second cover portion and covering one side edge portion of the at least one battery cell.

[0022] The vent space may be provided between the battery cell and the third cover portion.

[0023] In one embodiment, the at least one battery cell may be adhesively secured to an inner surface of the first cover portion and the second cover portion.

[0024] An end of the first cover part that is not connected to the third cover part and an end of the second cover part that is not connected to the third cover part may form an opening through which one side of the battery cell is exposed toward the pack case.

[0025] In one embodiment, the at least one battery cell is disposed between a first cover portion and a second cover portion of the cell cover, and may be spaced apart from the third cover portion so that a predetermined space is formed between the third cover portion and the at least one battery cell.

[0026] In this case, the vertical length of the first cover portion and the second cover portion of the cell cover can be longer than the vertical length of the at least one battery cell.

[0027] In one embodiment, the battery pack may include a heat sink in thermal contact with the cell unit to cool the cell unit.

[0028] In particular, the cell cover may be in contact with the heat sink.

[0029] In one embodiment, both ends of the cell cover extend toward the heat sink and may extend longer than the ends of the at least one battery cell so that a predetermined space is formed between the at least one battery cell disposed between the first cover part and the second cover part and the heat sink.

[0030] In an embodiment, the heat sink may include fixing grooves into which both ends of the cell cover are inserted and fixed.

[0031] In the present invention, the first cover part and the second cover part may further include a lower beading part formed at an end adjacent to the opening and indented inwardly toward the battery cell.

[0032] Here, the lower beading portion may be continuously formed along the longitudinal direction of the cell cover.

[0033] Also, the lower beading portion of the first cover portion and the lower beading portion of the second cover portion may be provided symmetrically with respect to the center of the cell cover.

[0034] Furthermore, the first cover portion and the second cover portion may further include an upper beading portion formed between the third cover portion and the battery cell and indented inward toward the battery cell.

[0035] The upper beading portion may be continuously formed along the longitudinal direction of the cell cover.

[0036] The upper beading portion of the first cover portion and the upper beading portion of the second cover portion may be provided symmetrically with respect to a center of the cell cover.

[0037] According to another embodiment, the first cover portion and the second cover portion include both the upper beading portion and the lower beading portion.

[0038] A vehicle according to yet another embodiment of the present invention may include at least one battery pack according to any one of the above-mentioned embodiments. Effect of the Invention

[0039] The battery pack of the present invention is based on the CTP concept, and by removing the module case, etc., it is possible to improve cooling performance, energy density, etc.

[0040] According to one aspect of the present invention, instead of housing a plurality of battery cells in separate module cases and mounting them in a pack case of a battery pack, the battery cells are only partially covered by a cell cover having a simplified structure and mounted directly in the pack case, thereby reducing the weight and volume of the entire battery pack and increasing the energy density of the battery pack. This also prevents damage to the battery cells that occurs during the process of mounting a plurality of battery cells directly in a case and using the battery pack, and makes it easier to control swelling of the battery cells and design a gas vent path.

[0041] In addition, by bonding and fixing the battery cells to the inner surface of the cell cover and forming spaces above and below the battery cells that allow for heat exchange and gas venting, efficient cooling and directional venting of the battery cells is possible. When using cells with improved safety such as LFP pouch cells, thermal resin is no longer necessary, which reduces manufacturing costs.

[0042] Furthermore, the cell cover is inserted and fixed into the fixing groove of the heat sink and acts as a cooling fin that transfers heat from the battery cell to the heat sink, thereby simplifying and streamlining the manufacturing process of the battery pack and further improving the cooling performance of the battery cell.

[0043] Furthermore, by blocking and fixing cell units, each of which contains at least one battery cell, to a pair of side plates and an integrated end cover, it is possible to facilitate handling and installation of the battery cells in the battery pack, simplify and lighten the structure required for installing the battery cells, and reduce manufacturing costs.

[0044] According to another aspect of the present invention, the beading portion of the cell cover can improve the assembly process between the cell cover and the battery cell, and the formation of an air layer between the cell units can reduce the heat transfer rate between the cell units.

[0045] In addition, when the battery cell swells, the battery cell is pressed by the elastic deformation of the beading portion of the cell cover, thereby minimizing the amount of swelling of the battery cell. [Brief description of the drawings]

[0046] [Figure 1] FIG. 1 illustrates a battery pack according to one embodiment of the present invention. [Diagram 2] FIG. 2 illustrates a battery assembly that may be included in a battery pack according to one embodiment of the present invention. [Diagram 3] FIG. 3 is a partially exploded perspective view of the battery assembly shown in FIG. 2. [Figure 4] FIG. 3 is an enlarged view of the bottom of the P1 region shown in FIG. [Diagram 5] 3 is a perspective view of a cell unit that can be included in the battery assembly shown in FIG. 2. [Figure 6] FIG. 6 is an exploded perspective view of the cell unit shown in FIG. 5. [Figure 7] 7 is a perspective view showing a cell cover of the cell unit shown in FIG. 6. [Figure 8] 8 is a diagram showing a mounting method of a cell unit to which the cell cover shown in FIG. 7 is applied. [Figure 9] 8 is a diagram showing a mounting method of a cell unit to which the cell cover shown in FIG. 7 is applied. [Figure 10] FIG. 2 is a perspective view illustrating a schematic configuration of a battery pack according to another embodiment of the present invention. [Figure 11] FIG. 13 is a perspective view illustrating a schematic configuration of a cell unit according to another embodiment of the present invention. [Figure 12] 11 is a schematic cross-sectional view of a cell unit according to another embodiment of the present invention. [Figure 13] FIG. 2 is a schematic cross-sectional view of a battery pack according to another embodiment of the present invention; [Figure 14] 13 is a view corresponding to FIG. 12 and showing another embodiment of the cell unit of FIG. 12. FIG. [Figure 15] 13 is a view corresponding to FIG. 12 and showing still another embodiment of the cell unit of FIG. 12. FIG. [Figure 16] 1 illustrates a vehicle according to an embodiment of the present invention; DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0047] Hereinafter, in order to clarify the solution to the technical problem of the present invention, the embodiment of the present invention will be described in detail with reference to the accompanying drawings. However, in describing the present invention, if the description of related known technology is considered to make the gist of the present invention unclear, the description will be omitted. Furthermore, the terms used in this specification are defined in consideration of the functions of the present invention, and may vary depending on the intentions or practices of the designer, manufacturer, etc. Therefore, the definitions of the terms described below should be based on the contents of this specification as a whole.

[0048] For reference, in this specification, directional terms are terms with respect to components shown in the accompanying drawings, and are relative terms that may be changed depending on the actual attitude and position of the components.

[0049] In the drawings, the size of each component or a specific part constituting each component may be somewhat exaggerated, omitted, or illustrated in a schematic manner for ease of explanation and clarity, and therefore the size of each component does not entirely reflect the actual size.

[0050] FIG. 1 is a diagram showing a battery pack according to one embodiment of the present invention.

[0051] As shown in FIG. 1 , the battery pack 10 may include at least one battery assembly 100 and a pack case 12 .

[0052] The battery assembly 100 may include a plurality of cell units 110. For example, a plurality of the cell units 110 may be arranged along the Y-axis direction. A plurality of battery assemblies 100 including such cell units 110 may be arranged along the X-axis direction and the Y-axis direction within the pack case 12.

[0053] The pack case 12 accommodates the battery assemblies 100 in its internal space. The pack case 12 has a mounting structure on which the battery assemblies 100 are directly mounted without a separate case, and may be configured to accommodate a plurality of battery assemblies 100 in separate mounting spaces for each battery assembly. To this end, the pack case 12 may include cross beams 12a, 12b that divide the internal space into a plurality of mounting spaces. The cross beams 12a, 12b may be configured to be spaced apart from each other or to intersect with each other to form the plurality of mounting spaces.

[0054] The pack case 12 may be made of a plastic or metal material, or may be made of any of a wide variety of battery pack exterior materials known at the time of filing of the present application.

[0055] Fig. 2 is a diagram showing a battery assembly that may be included in a battery pack according to an embodiment of the present invention. Fig. 3 is a partially exploded perspective view of the battery assembly shown in Fig. 2. Fig. 4 is an enlarged view of the bottom of the P1 area shown in Fig. 2.

[0056] 2 to 4, the battery assembly 100 includes a plurality of cell units 110, a pair of side plates 120, and a pair of integrated end covers 130, and may further include a handle unit 140 in some embodiments.

[0057] Fig. 5 is a perspective view of a cell unit that may be included in the battery assembly shown in Fig. 2. Fig. 6 is an exploded perspective view of the cell unit shown in Fig. 5.

[0058] 5 and 6, each of the cell units 110 may include at least one battery cell 105 and a cell cover 150 that at least partially encases an exterior of such battery cell 105. In addition to the at least one battery cell 105 and the cell cover 150, the cell unit 110 may include a bus bar frame 170 and an insulating cover 180.

[0059] In an embodiment of the present invention, the battery cell 105 is a pouch-type battery cell. The battery cell 105 is a basic unit for charging and discharging, and the cell cover 150 may only partially cover and support at least one battery cell 105. In addition, the battery cell 105 is characterized in that a vent space is provided between the cell cover 150 and the battery cell 105, which will be described in detail later.

[0060] The battery cell 105 corresponds to a basic unit of charging and discharging, and may be manufactured by accommodating an electrode assembly and an electrolyte material inside a pouch exterior material made of a laminate film containing a soft metal, and then sealing the pouch exterior material. In this case, the electrode assembly may be manufactured by interposing a separator between a positive electrode and a negative electrode. Also, an electrode lead 107 electrically connected to the electrode assembly may be provided so as to be exposed from the outside of the pouch exterior material of the battery cell 105. The electrode lead 107 includes a pair of a positive electrode lead and a negative electrode lead. Here, the positive electrode lead and the negative electrode lead may be provided at both front and rear ends in the longitudinal direction of the battery cell 105.

[0061] The battery cell 105 may have four edges, such as an upper edge, a lower edge, a front edge, and a rear edge, and all of the four edges may be sealed, or only the lower edge may be an unsealed portion where the pouch exterior material is folded. For example, the upper edge may be a sealed portion of the battery cell 105 that is folded twice, which is a so-called double side folding (DSF) structure, and the lower edge may be an unsealed portion.

[0062] The cell cover 150 may include venting holes 160 that are provided at various positions depending on the intended venting direction. Such venting holes 160 may be provided to form notches in predetermined portions of the cell cover 150.

[0063] The battery pack 10 including the cell cover 150 allows multiple battery cells 105 to be stably housed inside the pack case 12 without the need for a stacking frame such as a plastic cartridge or a separate module case.

[0064] The bus bar frame 170 may be configured to support the electrode lead 107 of at least one battery cell 105 covered by the cell cover 150 and to electrically connect such electrode lead 107 to the electrode leads 107 of other battery cells 105. In this case, the bus bar frame 170 may include terminals electrically connected to the electrode leads 107.

[0065] The insulating cover 180 may be configured to prevent short-circuiting of the electrode leads 107 or the bus bars. For this reason, the insulating cover 180 may be made of a polymeric synthetic resin having insulating properties.

[0066] 2 to 6, such cell units 110 may be configured so that a plurality of such cell units 110 are stacked side by side in their width direction (Y-axis direction in the figures). The pair of side plates 120 may be arranged at both ends of the width direction (stacking direction) of the plurality of cell units 110, and configured to support the plurality of cell units 110. For this reason, at least one of the pair of side plates 120 may include a support portion 122, an end cover connecting portion 124, and a handle connecting portion 126.

[0067] The support portion 122 may be configured to contact one side surface or the other side surface in the width direction of the multiple cell units 110 to support the multiple cell units 110. In this case, the support portion 122 may be configured in a plate-like structure.

[0068] The end cover connecting portion 124 can be configured to extend from the support portion 122 in its side direction (the X-axis direction in the drawing) and to connect to one end of the integrated end cover 130 in the side direction.

[0069] The handle coupling portion 126 may be configured to extend upward (in the Z-axis direction in the figure) from the support portion 122 and be coupled to at least one of the multiple handle units 140. As will be described later, the handle coupling portion 126 may be configured to be coupled to and detachable from the at least one handle unit 140.

[0070] Such a pair of side plates 120, together with the integrated end cover 130, can block or group the multiple cell units 110 while evenly distributing pressure applied to the multiple cell units 110 to the entire cell units 110. The pair of side plates 120 may be made of a metal material containing aluminum, or may be made of a material that combines aluminum and polymeric synthetic resin by insert molding.

[0071] A pair of integrated end covers 130 can be arranged at both ends of the multiple cell units 110 in the longitudinal direction (X-axis direction in the figure) to support the multiple cell units 110 and be configured to integrally cover the terminal portions of the battery cells 105 included in the multiple cell units 110.

[0072] That is, each of the integrated end covers 130 may be configured such that one end in the side direction is coupled to a first side plate of one of the pair of side plates 120 and the other end in the side direction is coupled to a second side plate of the other of the pair of side plates 120, so as to integrally cover the terminal portions of the battery cells 105 included in the multiple cell units 110. In this case, the integrated end cover 130 may have vent holes 132a at positions corresponding to the multiple cell units 110. Such an integrated end cover 130 may be made of a metal material or polymer synthetic resin containing aluminum, or may be made of a material in which a metal material containing aluminum and a polymer synthetic resin are combined by insert molding.

[0073] By applying such an integrated end cover 130 to the battery assembly 100, it is possible to omit the individual end covers that are applied to each cell unit 110 and cover the terminals or bus bar portions of the battery cells 105 included in that cell unit 110, thereby simplifying the manufacturing process.

[0074] The handle unit 140 may be configured to be held by a carrier transporting the battery assembly 100, or may be configured to be connected to a predetermined transport device for lifting or transporting the battery assembly 100.

[0075] Such a handle unit 140 may be configured to be detachably coupled to the pair of side plates 120. Furthermore, the handle unit 140 may be made of a metal material having a predetermined strength, a polymeric synthetic resin, or a combination thereof.

[0076] The above-described battery assembly 100 is scalable by increasing the number of stacked cell units 110.

[0077] 3, the pair of side plates 120 and the pair of integrated end covers 130 of the battery assembly 100 can be coupled to each other to block or group a plurality of cell units 110. To this end, the integrated end cover 130 can include a terminal cover portion 132, a first coupling portion 134a, and a second coupling portion 134b.

[0078] The terminal cover portion 132 may be configured to collectively cover the terminal portions (electrode lead portions) of the battery cells 105 included in the multiple cell units 110. Such a terminal cover portion 132 may include vent holes 132a at positions corresponding to each of the cell units 110.

[0079] The first coupling portion 134a may be configured to extend from the terminal cover portion 132 toward the first side plate 120a and be coupled to the end cover coupling portion 124 of the first side plate 120a. In this case, the first coupling portion 134a and the end cover coupling portion 124 may be coupled to each other by a fastening member such as a bolt or a rivet.

[0080] The second coupling portion 134b may be configured to extend from the terminal cover portion 132 toward the second side plate 120b and be coupled to the end cover coupling portion 124 of the second side plate 120b. In this case, the second coupling portion 134b and the end cover coupling portion 124 may be coupled to each other by a fastening member such as a bolt or a rivet.

[0081] Meanwhile, the handle unit 140 can be detachably (connected and separated) connected to the handle connecting portion 126 of the corresponding side plate 120 in various ways.

[0082] As shown in FIG. 4, the first coupling portion 134a of the integrated end cover 130 can be coupled to the end cover coupling portion 124 of the first side plate 120a by a fastening member B.

[0083] Furthermore, the integrated end cover 130 may include a cell unit support portion 136. The cell unit support portion 136 may be configured to extend from the terminal cover portion 132 having the vent holes 132a to the bottom surfaces of the multiple cell units 110 and support the multiple cell units 110. In this case, the cell unit support portion 136 may be configured to support the lower ends of the bus bar frames 170 provided on the multiple cell units 110.

[0084] In this way, by blocking and fixing the cell units 110, each of which includes at least one battery cell 105, to a pair of side plates 120 and an integrated end cover 130, it is possible to facilitate handling and installation of the battery cells 105 to be attached to the battery pack 10, while simplifying and lightening the structure required to install the battery cells 105, thereby reducing manufacturing costs.

[0085] According to the battery pack 10 described above, in one embodiment including the cell cover 150, a configuration in which multiple battery cells 105 are stacked horizontally in a vertically upright position can be easily realized.

[0086] Furthermore, according to an embodiment of the present invention, since the battery cells 105 are directly accommodated in the pack case 12 without being modularized, it is possible to manufacture a battery pack 10 that does not require a module case for a battery module. Therefore, by reducing the space occupied by such a module case, more battery cells 105 can be arranged inside the pack case 12. This has the effect of further improving the energy density of the battery pack 10. In particular, by directly assembling the battery cells 105 having a soft case, such as a pouch-type battery cell, into the pack case 12 of the battery pack 10, it is possible to maximize the space utilization rate of the battery pack 10 and significantly improve the energy capacity.

[0087] Moreover, by wrapping the battery cells 105 in the cell covers 150, the battery cells 105 can be easily strengthened, and a structure in which the battery cells are directly stacked inside the pack case 12 can be easily realized. Therefore, the ease of assembly and mechanical stability of the battery pack 10 can be improved.

[0088] Fig. 7 is a perspective view showing a cell cover of the cell unit shown in Fig. 6. The cell unit 110 and the cell cover 150 will be described in more detail below with reference to Figs.

[0089] As described with reference to FIGS. 5 and 6 , the cell unit 110 may include a cell cover 150 that partially covers the exterior of at least one battery cell 105.

[0090] The cell cover 150 may be configured to partially encase the exterior of the at least one battery cell 105. That is, the cell cover 150 may be configured to encase at least one battery cell 105 among the multiple battery cells 105 included in the battery pack 10. Also, the cell cover 150 may be provided to at least partially encase the battery cell 105. Furthermore, the cell cover 150 may be configured to support the at least one battery cell 105 in an upright state.

[0091] For example, as shown in FIG. 6, the cell cover 150 may be configured to partially enclose the exteriors of the three battery cells 105 while supporting the battery cells 105 in an upright position.

[0092] As shown in Fig. 6, each battery cell 105 has two wide sides, and when the battery cell 105 is a pouch-type battery cell, a sealed portion or a folded portion of the pouch exterior material may be formed at the edge (border) portion of such wide sides. Therefore, it is generally difficult to stack pouch-type battery cells in a vertically standing state with the narrow side facing down. However, in the battery pack 10 according to the present invention, the cell cover 150 may be configured to support the standing state, i.e., the upright state, of the wrapped battery cell 105 while wrapping one or more battery cells 105.

[0093] 7 in detail, the cell cover 150 may include a first cover portion 152 covering one side surface of the at least one battery cell 105, a second cover portion 154 covering the other side surface of the at least one battery cell 105, and a third cover portion 156 connecting the first cover portion 152 and the second cover portion 154 and covering an upper edge portion of the at least one battery cell 105. In this case, the vent hole 160 may be provided in the third cover portion 156 of the cell cover 150.

[0094] For example, the cell cover 150 may be formed in a "C" shape, a "u" shape, or an "n" shape that surrounds three sides of at least one battery cell 105. The cell cover 150 may be configured so that a plurality of battery cells 105 can be stacked horizontally in a vertically standing state. For example, similar to the embodiment of the battery pack 10 described above, a plurality of cell units 110 may be stacked on top of each other in the horizontal direction (Y-axis direction), and each cell cover 150 may be formed in a shape that encases one or more battery cells 105. In this case, the cell cover 150 may stably hold a configuration in which a plurality of battery cells 105 are stacked horizontally in a standing state.

[0095] In addition, by making the cell cover 150 surround three sides of at least one battery cell 105, it is possible to easily realize a configuration in which the bus bars and terminals of each unit of each cell unit 110 are arranged on the side that is not surrounded by each cell cover 150.

[0096] It can be said that the battery cell 105, such as a pouch-type battery cell, is formed as a substantially hexahedron. Furthermore, the electrode leads 107, i.e., the negative electrode lead and the positive electrode lead, may be formed on two of the six faces. The cell cover 150 is provided so as to enclose at least a part of three of the remaining four faces of the six faces of the hexahedral battery cell 105, excluding the two faces on which the electrode leads 107 are formed.

[0097] According to this embodiment of the present invention, the direction of exhaust of flames, etc. can be guided to the exposed side surface (the portion where the electrode lead 107 is formed) of the cell cover 150. For example, according to the embodiment, since the front side and the rear side of the cell cover 150 where the electrode lead 107 is located are open, it is possible to exhaust flames, etc. in the direction of the opening. In particular, when the front and rear of the cell cover 150 are formed in an open shape as described above, directional venting along the longitudinal direction of the battery cell 105 can be easily realized. Alternatively, when the lower end or the upper end of the cell cover 150 is formed in an open shape, directional venting to the open side surface (open end) of the lower end or the upper end of the cell cover 150 can be realized.

[0098] In a pouch-type battery cell, the upper edge portion as a sealed portion may be relatively weaker against the discharge of high-temperature gas and flame than the lower edge portion as an unsealed portion. However, according to the above embodiment, the upper edge portion as a sealed portion is disposed to face the cell cover 150, which may be more advantageous for directional venting.

[0099] In the illustrated example, the third cover portion 156 may be configured to encase the top of the upper edge portion of the battery cell 105 housed therein.

[0100] The first cover part 152 may be formed in a shape extending downward from one end of the third cover part 156. For example, the first cover part 152 may be formed in a shape extending long downward from the left end part of the third cover part 156. The first cover part 152 may be configured to enclose a wide surface of the battery cell 105 housed therein.

[0101] The second cover portion 154 may be disposed horizontally spaced apart from the first cover portion 152. The second cover portion 154 may be formed in a shape extending downward from the other end of the third cover portion 156. For example, the second cover portion 154 may be configured to extend downward from the right end portion of the third cover portion 156. Furthermore, the second cover portion 154 may be configured to enclose a wide surface of the battery cell 105 housed therein. In the embodiment, an internal space may be defined by the third cover portion 156, the first cover portion 152, and the second cover portion 154. The cell cover 150 may house one or more battery cells 105 in the internal space thus defined.

[0102] In the illustrated example, the cell cover 150 partially encases the battery cell 105 so as to form an opening where at least one side, particularly the lower side, of the enclosed battery cell 105 is exposed to the pack case 12. According to such an aspect of the present invention, it is possible to further improve the cooling efficiency of the battery pack 10. In particular, in the case of one embodiment of the present invention, since a portion of each battery cell 105 can be directly exposed to the pack case 12, heat of each battery cell 105 can be effectively discharged to the outside through the pack case 12.

[0103] According to this embodiment of the present invention, it is possible to easily realize a configuration in which one cell cover 150 supports and protects one or more battery cells 105. In particular, according to the embodiment, the lower edge portion of the battery cell 105 is located adjacent to the open end of the cell cover 150, and faces the pack case 12 without being enclosed by the cell cover 150, and can be in direct face-to-face contact with the pack case 12. Therefore, heat from the battery cell 105 enclosed by the cell cover 150 can be quickly and smoothly discharged to the lower pack case 12 side. Therefore, the cooling performance of the battery pack 10 can be more effectively ensured.

[0104] In particular, such a configuration can be more effectively implemented when cooling is performed mainly in the lower part of the pack case 12. For example, in the case of a battery pack mounted on an electric vehicle, since it is mounted on the lower part of the vehicle body, cooling can be performed mainly in the lower part of the pack case 12. In this case, when the lower edge part of each battery cell 105 faces and contacts the pack case 12 as in the above embodiment, heat is quickly transferred from each battery cell 105 to the pack case 12 side, and cooling performance can be further improved.

[0105] Moreover, according to the embodiment, when high-temperature gas, flame, or the like is discharged from the battery cell 105 in a situation such as thermal runaway, the discharged gas or flame can be effectively prevented from moving upward. In particular, when an occupant is positioned above the battery pack 10, such as in an electric vehicle, according to the embodiment, it is possible to suppress or delay the gas, flame, or the like from moving toward the occupant.

[0106] The cell cover 150 may be integrally formed. In this case, the cell cover 150 may be formed by bending a plate-like metal plate. That is, the cell cover 150 may be formed from a single bent plate.

[0107] The cell cover 150 may be formed into a shape that encloses one or more battery cells 105 by bending both ends of a single plate material in the same direction. In particular, when one cell cover 150 includes a first cover portion 152, a second cover portion 154, and a third cover portion 156, the first cover portion 152, the second cover portion 154, and the third cover portion 156 may be configured from a single plate. In this case, the cell cover 150 can be said to be an integration of multiple components.

[0108] Here, each component can be divided by a bent portion. In particular, two bent portions can be formed in one plate. The first cover portion 152, the second cover portion 154, and the third cover portion 156 can be divided based on these two bent portions. In particular, the third cover portion 156 can be formed in the center of one plate, and the first cover portion 152 and the second cover portion 154 can be formed by bending or folding both sides downward around the third cover portion 156. In this way, the configuration of forming bent portions in one plate to form the cell cover 150 can be realized by various methods such as press forming and roll forming.

[0109] According to such an embodiment of the present invention, the manufacture of the cell cover 150 can be further simplified. In addition, the cell cover 150 having a simplified structure may be made of a metal material having higher rigidity than the case of the battery cell 105, such as a pouch exterior material, thereby protecting at least one battery cell 105 covered by the cell cover 150 from external impact and vibration. In addition, in this case, the thermal conduction performance of the cell cover 150 is further improved, and the cooling performance can be further improved.

[0110] For example, the cell cover 150 may be made of a material including stainless steel (SUS), which is easy to process and highly corrosion-resistant. In addition, the cell cover 150 may be made of various materials other than SUS in order to ensure rigidity. In particular, the cell cover 150 may be made of a metal material. For example, the cell cover 150 may be made of a chromium (CR)-based metal material. Such a metal material can more stably maintain the stacked state of the battery cells 105 and more safely protect the battery cells 105 from external impact. In addition, as illustrated, when the cell cover 150 is made of a steel material such as SUS, it can maintain a stable structure as a whole even if a flame occurs from the battery cell 105 because of its high melting point. In particular, since the steel material has a higher melting point than the aluminum material, it can maintain a stable shape without being melted by the flame emitted from the battery cell 105. Therefore, it is possible to excellently achieve the effect of preventing or delaying the propagation of flame between the battery cells 105, the effect of controlling vents, and the like.

[0111] The cell cover 150 may include an insulating coating layer formed on an inner surface thereof. The insulating coating layer may be formed by coating, applying, or attaching any one of insulating materials such as silicone resin, polyamide, and rubber. According to the configuration of the insulating coating layer of the cell cover 150 according to the present embodiment, the insulating coating effect can be maximized with a minimum amount of coating. In addition, since the insulating coating layer is applied to the inner surface of the cell cover 150, the insulation between the battery cell 105 and the cell cover 150 can be improved.

[0112] 5 and 6, the cell unit 110 may further include a clamp member configured to clamp the cell cover 150. The clamp member may be configured to clamp the cell cover 150 into which at least one battery cell 105 is inserted, to prevent both ends (the end of the first cover part 152 and the end of the second cover part 154) of the cell cover 150 from being separated from each other or to prevent the inserted battery cell 105 from being detached from the cell cover 150.

[0113] Such a clamp member may be made of a tape or a metal material having elasticity. In particular, the tape may include a base layer and an adhesive layer formed on the surface of the base layer.

[0114] The clamp member may be located outside the battery cell 105 that is not enclosed by the cell cover 150. For example, the cell cover 150 may be configured to expose the lower end of the battery cell 105 to the outside without enclosing it. In this case, the clamp member may be attached to the lower end of the cell cover 150 that is exposed to the outside without enclosing the battery cell 105.

[0115] A plurality of the clamp members may be included in one cell unit 110. For example, three clamp members may be arranged spaced apart in the front-rear direction (the X-axis direction in the drawing) to connect the end of the first cover portion 152 and the end of the second cover portion 154. Here, the front-rear direction can be said to refer to the horizontal direction perpendicular to the stacking direction of the battery cells 105.

[0116] According to the embodiment, it is possible to prevent the ends of the cell cover 150 from separating in one cell unit 110. Therefore, it is possible to stably maintain the accommodation state of the cell cover 150 and the battery cells 105 inside the pack case 12. In particular, according to the embodiment, it is possible to stably maintain the self-supporting configuration of the cell cover 150.

[0117] Meanwhile, although FIG. 6 shows that the number of battery cells 105 covered by one cell cover 150 is three, the number of battery cells 105 covered by the cell cover 150 may be variously changed depending on the scale of the cell cover 150, such as less than three, e.g., one, or more than three, e.g., five. A configuration for changing the number of battery cells 105 enclosed by the cell cover 150 can be easily realized. In particular, according to one embodiment of the present invention, the number of unit cells accommodated by the cell cover 150 can be easily changed by changing the width of the cell cover 150 (the width along the Y-axis direction of the third cover portion 156). Therefore, in this case, the capacity or output of one cell cover 150 can be easily changed.

[0118] Describing the cell cover 150 in more detail, the cell cover 150 can cover and support at least one battery cell 105. To this end, the cell cover 150 can include a first cover portion 152, a second cover portion 154, and a third cover portion 156.

[0119] When the cell cover 150 covers one battery cell 105, the first cover portion 152 may cover one side of the battery cell 105. The second cover portion 154 may cover the other side of the battery cell 105. The third cover portion 156 may connect the first cover portion 152 and the second cover portion 154 and cover an upper edge portion of the battery cell 105.

[0120] When the cell cover 150 covers two or more battery cells 105, the first cover portion 152 may cover one side surface of the leftmost battery cell 105 among the two or more battery cells 105. The second cover portion 154 may cover the other side surface of the rightmost battery cell 105 among the two or more battery cells 105. The third cover portion 156 may connect the first cover portion 152 and the second cover portion 154, and cover upper edge portions of the two or more battery cells 105.

[0121] As shown in FIG. 6, the vertical length L1 of the first cover portion 152 and the second cover portion 154 of the cell cover 150 may be longer than the vertical length (L2) of the battery cell 105. Since the areas of the first cover portion 152 and the second cover portion 154 are set to be larger than the area of ​​the battery cell 105, the protective effect and safety of the battery cell 105 can be maximized. The vertical lengths L1 of the first cover portion 152 and the second cover portion 154 may be the same. In this case, the cell cover 150 can be more easily configured to be self-supporting.

[0122] In particular, as shown in FIG. 7, the cell cover 150 may be configured so that the height of both sides is higher than the height of the battery cell 105 by an amount corresponding to m1, or may be configured so that the height is higher by an amount corresponding to m1+m2.

[0123] First, at least one battery cell 105 is disposed between the first cover portion 152 and the second cover portion 154 of the cell cover 150, and may be disposed away from the third cover portion 156 by an amount corresponding to m1 so that a predetermined space is formed between the battery cell 105 and the third cover portion 156. Such a predetermined space is the above-mentioned vent space. That is, the vent space may be provided between the battery cell 105 and the third cover portion 156.

[0124] Pouch-type battery cells have the advantage of being lightweight, less likely to leak electrolyte, and flexible in shape, allowing the same capacity of secondary batteries to be realized with a smaller volume and mass. However, there is a risk of explosion due to overheating, so ensuring safety is one of the major challenges. Overheating of pouch-type battery cells can occur for various reasons, one example being when an overcharge exceeds the limit through the pouch-type battery cell. When an overcurrent flows, the pouch-type battery cell generates heat due to Joule heat, causing the internal temperature of the battery cell to rise rapidly. The sudden rise in temperature can cause a decomposition reaction of the electrolyte and generate gas. This increases the internal pressure of the pouch exterior material, causing a swelling phenomenon, which is a type of expansion phenomenon, and can cause serious problems such as the explosion of the secondary battery. In addition to this overcurrent, if gas is generated inside the pouch-type battery cell due to exposure to high temperatures or external impact, it is necessary to effectively exhaust the gas to ensure the safety of the secondary battery. The discharge of gas generated inside the secondary battery to the outside is called venting. The cell cover 150 included in the battery pack 10 according to one embodiment of the present invention is configured to allow vent gas to be discharged to the space between the battery cell 105 and the third cover part 156, thereby ensuring the safety of the secondary battery.

[0125] In this case, at least one battery cell 105 may be adhesively fixed to the inner surfaces of the first cover part 152 and the second cover part 154. The adhesive member may have thermal conductivity. Such adhesion allows the cell cover 150 to be firmly bonded to the battery cell 105 and also helps to discharge heat generated from the battery cell 105 to the outside of the battery cell 105. In addition, since a gap between the battery cell 105 and the third cover part 156 can be maintained, a vent space can be maintained.

[0126] Additionally, the first cover portion 152 and the second cover portion 154 of the cell cover 150 may extend downwardly longer than at least one battery cell 105 disposed therebetween by an amount corresponding to m2.

[0127] Among the ends of the first cover portion 152, end portion C1 that is not connected to the third cover portion 156, and among the ends of the second cover portion 154, end portion C1 that is not connected to the third cover portion 156 form an opening portion in which the underside of the battery cell 105 is exposed toward the pack case 12.

[0128] 8 and 9 show a mounting method of the cell unit 110 having the cell cover 150 shown in FIG.

[0129] 8, the battery pack 10 may further include a heat sink 200 that is in thermal contact with the cell unit 110 to cool the cell unit 110. Here, the heat sink 200 refers to an object that absorbs and dissipates heat from another object through direct or indirect thermal contact. Such a heat sink 200 may be disposed on the bottom surface of the pack case 12 shown in FIG.

[0130] In particular, the cell cover 150 may be in contact with the heat sink 200 when attached. In this case, the cell cover 150 serves as a cooling fin that transfers heat from the battery cell 105 to the heat sink 200, thereby simplifying and streamlining the manufacturing process of the battery pack and further improving the cooling performance of the battery cell 105.

[0131] Also, the heat sink 200 may include a fixing groove 210 into which both ends of the cell cover 150 (the end C1 of the first cover part 152 and the end C1 of the second cover part 154) are inserted and fixed. The fixing groove 210 may have a slit shape corresponding to the shape of the end of the cell cover 150. The fixing groove 210 may be formed at the upper end of the heat sink 200 at a position and shape corresponding to the end of the cell cover 150. One or more ends of the cell cover 150 may be fitted into one fixing groove 210. According to this embodiment of the present invention, the connection between the cell cover 150 and the heat sink 200 may be further improved. Therefore, even in a situation where vibration or impact is applied to the battery pack 10 or swelling of the battery cell 105 occurs, the stacked state of the cell cover 150 and the battery cell 105 accommodated therein may be stably maintained. Also, according to the embodiment, the cell cover 150 may be effectively prevented from moving in the left-right direction (Y-axis direction). Furthermore, according to the embodiment, the assembly position of the cell cover 150 can be guided by the fitting configuration between the cell cover 150 and the heat sink 200. Therefore, in this case, the ease of assembly of the battery pack 10 can be further improved.

[0132] Both ends of the cell cover 150 may extend toward the heat sink 200. In addition, both ends of the cell cover 150 may extend toward the heat sink 200 longer than the ends of at least one battery cell 105 disposed between the first cover part 152 and the second cover part 154, so that an additional vent space DV2 for directional venting is formed between the heat sink 200 and the at least one battery cell 105.

[0133] 9, the cell unit 110 may be fixed by inserting both ends of the cell cover 150 into the fixing groove 210 of the heat sink 200. In this manner, the cell cover 150 may be formed in a shape such that at least one end is fitted into the heat sink 200. Specifically, the lower end of the cell cover 150 may be fastened and fixed by being fitted into the fixing groove 210. As a result, vent spaces DV1 and DV2 capable of heat exchange and gas venting are formed above and below the battery cell 105, respectively, thereby enabling efficient cooling and directional ventilation of the battery cell 105.

[0134] Also, a plurality of cell covers 150 may be included in the battery pack 10. When a plurality of cell covers 150 are included, as shown in FIG. 9, the plurality of cell covers 150 may be arranged spaced apart from each other. For example, the plurality of cell covers 150 may be arranged spaced apart from each other in the Y-axis direction. Since there is a space between the cell covers 150, direct heat transfer between the cell covers 150 can be blocked. Furthermore, since there is a space between the cell covers 150, a separate member required for configuring the battery pack 10 can be inserted. Alternatively, a heat insulating pad, a flame suppression pad, or the like may be interposed in at least a part of the space between the plurality of cell covers 150. Such a heat insulating pad or a flame suppression pad can prevent heat or flame that may be generated in any one of the cell covers 150 from being transferred to the other cell cover 150 side and affecting the other battery cells 105. The flame suppression pad may be formed of a heat-resistant resin such as polyvinyl chloride resin, a material such as silicon or ceramic, a composite of a heat-resistant resin and a ceramic or glass filler, or a metal plate with an insulating coating, but this is merely exemplary, and any flame-retardant material will suffice. It is desirable that the battery cell 105 is made of a material that does not decompose, melt, or ignite at least up to a temperature at which the battery cell 105 experiences thermal runaway (for example, 150° C. to 200° C.).

[0135] Furthermore, when the battery pack 10 includes a plurality of stacked cell covers 150, an adhesive member may be interposed between the cell covers 150. For example, an adhesive member may be interposed between the two cell covers 150 at their portions facing each other to bond and fix them together. Such an adhesive configuration can realize a stronger connection configuration between the plurality of cell covers 150.

[0136] Between the battery cell 105 and the cell cover 150, the above-mentioned vent space DV1 formed as a space between the battery cell 105 and the cell cover 150 is provided. Also, between the battery cell 105 and the heat sink 200, an additional vent space (DV2) formed as a space between the battery cell 105 and the heat sink 200 is provided. According to such an aspect of the present invention, when a thermal runaway occurs in a specific battery cell, a thermal event can be effectively dealt with. In particular, according to the present invention, among the three elements (fuel, oxygen, and ignition source) that generate a flame, the accumulation and discharge of heat that corresponds to the ignition source can be blocked or appropriately controlled. Furthermore, according to the present invention, in order to block the accumulation of heat and prevent the discharge of a flame, the vent spaces DV1 and DV2 that enable vent gas discharge control and directional venting can be easily realized by a configuration that simply includes a cell cover 150 having the height of both sides higher than the height of the battery cell 105.

[0137] Above and below the battery cell 105, vent spaces DV1 and DV2 capable of heat exchange and gas venting are formed, respectively, and the gas in these vent spaces DV1 and DV2 can be discharged to the exposed side of the cell cover 150. In addition, the vent spaces DV1 and DV2 are provided for each cell unit 110 in each cell unit 110. In this case, even if thermal runaway occurs in any one of the battery cells 105, the flame and gas generated in that battery cell 105 can be discharged only to the vent spaces DV1 and DV2 of the cell cover 150 and the exposed side of the cell cover 150 communicating therewith. Therefore, the flame and gas do not propagate to other battery cells 105 enclosed by other cell covers 150 arranged adjacent to the side of the battery cell 105 in which thermal runaway occurs. In other words, even if thermal runaway occurs in any one of the battery cells 105, the influence of thermal runaway on the other battery cells 105 can be minimized. This reliably prevents the propagation of flames and gases between the cell units 110. In this manner, the present invention enables efficient cooling and directional ventilation of the battery cells 105.

[0138] On the other hand, in a typical battery pack, thermal resin is used to improve the heat transfer performance between different components. The purpose of the thermal resin is to reduce the thermal resistance of the contact between the components. In the unlikely event that a safer cell such as an LFP pouch cell is used as the battery cell 105, the battery pack 10 of the present invention can be cooled efficiently enough to omit the thermal resin. Therefore, the omission of the thermal resin can be expected to reduce the manufacturing cost.

[0139] Fig. 10 is a perspective view showing a schematic configuration of a battery pack according to another embodiment of the present invention, Fig. 11 is a perspective view showing a schematic configuration of a cell unit according to another embodiment of the present invention, and Fig. 12 is a schematic cross-sectional view of a cell unit according to another embodiment of the present invention. Note that the same or similar reference symbols are used for the same components as those in the previous embodiment, and repeated explanations will be omitted.

[0140] 10 to 12, a battery pack 10' according to another embodiment of the present invention includes a battery assembly 100' including a plurality of cell units 110', and a pack case 12'.

[0141] The pack case 12' has an empty space formed therein, and can accommodate a plurality of cell units 110'. For example, the pack case 12' can include a pack tray 14 and a pack cover 16. The pack tray 14 is formed in a box shape with an open upper end, and can accommodate a plurality of cell units 110' in the internal space. Furthermore, the pack cover 16 can be formed in the shape of a lid that covers the open upper end portion of the pack tray 14. In this case, the pack cover 16 can be formed in a box shape with an open lower end.

[0142] Similar to the above-described cell unit 110, the cell unit 110' may include a battery cell 105 and a cell cover 150' that partially encases and supports the battery cell 105. As shown in Fig. 11, the cell cover 150' may be configured to encase the battery cell 105 in the internal space of the pack case 12'.

[0143] 10, the cell cover 150' may be placed directly on the bottom surface of the pack tray 14. In this case, a part of the cell cover 150', for example, the lower end portion of the cell cover 150' may be placed in direct contact with the bottom surface of the pack tray 14. The cell cover 150' may be configured such that when the lower end portion is placed in this manner, the placed state is stably maintained.

[0144] The cell cover 150' may be formed in a shape that partially encases the battery cell 105 so that at least one side of the encased battery cell 105 is exposed to the outside. That is, the cell cover 150' may be formed in a shape that does not completely encase the battery cell 105 as a whole but only partially encases it. In particular, the cell cover 150' may be configured such that a lower edge portion of the battery cell 105 is exposed toward the pack case 12'.

[0145] According to this embodiment, the lower edge portion of the battery cell 105 can directly face and contact the bottom surface of the pack tray 14, so that the cooling performance of the battery pack 10' can be more effectively ensured. That is, heat released from each battery cell 105 can be directly transferred to the pack case 12', and as a result, the cooling performance is improved. In addition, in this case, since there is no need to provide a separate cooling structure between the battery cell 105 and the pack case 12', it is possible to achieve efficient cooling performance. Furthermore, in this case, a space for a coolant such as air to flow in may not be provided between the battery cells 105. Meanwhile, in the battery pack 10', a thermal interface material (TIM) may be interposed to improve the heat transfer performance between different components. For example, a TIM may be filled between the battery cell 105 and the cell cover 150', between the cell cover 150' and the pack case 12', and / or between the battery cell 105 and the pack case 12'. In this case, the cooling performance of the battery pack 10' may be further improved.

[0146] The TIM is used to reduce the contact thermal resistance between components. In battery packs where cooling is important, it is necessary to improve the thermal performance of the entire system by using a material that can minimize the contact thermal resistance. Examples of TIM include thermally conductive grease, thermally conductive sheets, thermally conductive pads, thermally conductive adhesives, and PCMs (phase change materials). To give a specific example, the TIM can be any one of thermally conductive silicone-based bonds, thermally conductive silicone pads, and thermally conductive acrylic bonds. Thermally conductive silicone-based adhesives and thermally conductive acrylic adhesives are commercially available as one-part or two-part types and can be applied between different components by coating or injection methods. Since the thermally conductive silicone pad includes a base film such as a double-sided tape and release papers above and below it, it can be applied between different components by a bonding method after peeling off the release papers. The heat dissipating silicone adhesive, heat dissipating silicone pad, and heat dissipating acrylic adhesive have higher thermal conductivity than a typical adhesive, and therefore can further increase the amount and speed of heat transfer between different components. Therefore, according to this embodiment of the present invention, the heat dissipation performance of the battery cell 105 can be further improved, and the cooling performance of the battery pack 10′ can be further improved.

[0147] On the other hand, the cell unit 110' is characterized in that the cell cover 150' includes a beading portion as a means for easily receiving the battery cell 105 in the cell cover 150'.

[0148] For example, as shown in FIG. 12, the aforementioned vent space DV1 is provided between the battery cell 105 and the cell cover 150', which is similar to the previously described embodiment, and the cell cover 150' may have lower beading portions 152a, 154a in which the lower portion of the lower edge of the battery cell 105 is curved toward the internal space of the cell cover 150'.

[0149] That is, the cell cover 150′ includes a first cover portion 152 and a second cover portion 154 similar to the cell cover 150, and the first cover portion 152 and the second cover portion 154 further include lower beading portions 152a, 154a formed at ends adjacent to the opening portion exposing the battery cell 105. The lower beading portions 152a, 154a are curved inward toward the battery cell 105.

[0150] In addition, the cell unit 110' may be configured so that the lower edge portion of the battery cell 105 is positioned above the bottom end of the cell cover 150', as shown by "h1" in FIG. 12, so that the lower edge portion of the battery cell 105 is positioned higher than the bottom end of the cell cover 150'.

[0151] More specifically, the lower beading portions 152a, 154a are provided at the lower ends of the first cover portion 152 and the second cover portion 154, and are continuous along the longitudinal direction of the cell cover 150' as shown in Fig. 11, and the lower beading portion 152a at the lower end of the first cover portion 152 and the lower beading portion 154a at the lower end of the second cover portion 154 may be provided symmetrically with respect to the center C of the cell cover 150' shown in Fig. 12. As a result, the cell cover 150' according to this embodiment may be configured such that the distance between the first cover portion 152 and the second cover portion 154 is narrow at the lower beading portions 152a, 154a.

[0152] Therefore, for example, when the first cover part 152 and the second cover part 154 are pulled in opposite directions to each other so that the gap between the first cover part 152 and the second cover part 154 is slightly widened, the lower edge part of the battery cell 105 is inserted so as to be positioned above the lower beading parts 152a and 154a, and the first cover part 152 and the second cover part 154 are returned to their original state, the lower part of the battery cell 105 may be supported in a state in which it is raised by "h1" by the lower beading parts 152a and 154a as shown in Fig. 12. When one cell unit 110' is formed by one cell cover 150' and three battery cells 105 as in the embodiment of Fig. 12, adhesive sheets may be applied to the surfaces of the battery cells 105 facing each other, and an adhesive sheet may also be applied between one surface of the outermost battery cell 105 and the first cover part 152 or the second cover part 154. In this case, the outermost battery cell 105 is supported at its lower part by the lower beading portions 152a, 154a, and the central battery cell 105 can be prevented from detaching downwardly by the compressive force exerted laterally by the first cover portion 152 and the second cover portion 154 and the adhesive force with the outermost battery cell 105.

[0153] According to this embodiment, the assembly can be guided so that the battery cell 105 is supported directly above the lower beading portions 152a, 154a of the cell cover 150. Therefore, the vent space DV1, which is a separation space between the third cover portion 156 of the cell cover 150 and the upper edge portion of the battery cell 105, can be well maintained, and at the same time, a process for configuring the cell unit 110′ can be more easily performed so that the lower edge portion of the battery cell 105 is positioned above the bottom end of the cell cover 150.

[0154] Meanwhile, as shown in Fig. 13, a battery pack 10' according to another embodiment of the present invention may be configured to include a heat sink 200'. In particular, the battery pack 10' may be provided in the form of a heat sink having a flow path through which cooling water flows on the bottom plate of the pack tray 14 in order to reduce weight and simplify the components.

[0155] According to the configuration of the cell cover 150' of the present embodiment, the battery cells 105 may be disposed such that their lower edge portions are exposed below the cell cover 150' through the lower opening of the cell cover 150' and face the bottom plate of the pack tray 14. A thermal resin 220 may be provided between the lower edge portions of the battery cells 105 and the bottom plate of the pack tray 14. Therefore, the battery pack 10' according to another embodiment of the present invention can dissipate heat from each battery cell 105 from the lower edge portion of each battery cell 105 to the thermal resin 220 to the pack tray 14 functioning as a heat sink 200'.

[0156] In this embodiment, the heat sink 200' has a thermal resin 220 interposed between the plurality of battery cells 105. The thermal resin 220 may be applied to an upper surface of the heat sink 200'. Then, a plurality of cell units 110', i.e., a plurality of battery cells 105 and a plurality of cell covers 150', may be placed on the upper surface of the heat sink 200' on which the thermal resin 220 is applied.

[0157] Here, the thermal resin 220 may be made of a material that is thermally conductive and adhesive. The thermal resin 220 can transfer heat to the heat sink 200' so that heat generated in the battery cell 105 can be dissipated through the heat sink 200'. In addition, since the thermal resin 220 has adhesive properties, the cell cover 150' can be structurally bonded to the heat sink 200'.

[0158] In this embodiment, the battery cells 105 to which the cell covers 150' are coupled may be directly placed on the upper surface of the heat sink 200' to which the thermal resin 220 is applied. In this case, the cell units 110' may be stably coupled and fixed to the upper surface of the heat sink 200' by the thermal resin 220. In particular, the battery cells 105 and the cell covers 150' included in each cell unit 110' may be formed such that the length in the vertical direction (Z-axis direction) is longer than the width in the horizontal direction (Y-axis direction). Therefore, the battery cells 105 and the cell covers 150' may be said to be placed in an upright state, that is, in an upright state, on the upper surface of the heat sink 200'. In this case, the thermal resin 220 may more stably hold the upright state of the cell covers 150'.

[0159] In addition, according to the configuration of the lower beading portions 152a, 154a of the cell cover 150', as shown in FIG. 13, an air layer 230 may be formed between the lower beading portion of any one of the cell units 110' (e.g., the lower beading portion 154a of the outermost battery cell 105 on the left side) and the lower beading portion of another one of the cell units 110' (e.g., the lower beading portion 152a of the central battery cell 105). Such an air layer 230 may act to reduce the heat transfer rate between the cell units 110'. Therefore, the configuration of the lower beading portions 152a, 154a of the cell cover 150' has an advantageous effect in preventing heat transfer between the cell units 110'.

[0160] Furthermore, the cell cover 150' according to the present embodiment may be advantageous in preventing swelling of the battery cell 105. When swelling of the battery cell 105, such as a pouch-type battery cell, occurs, the swelling pressure acts in a direction that stretches (straightens) the lower beading portions 152a and 154a. At this time, the lower beading portions 152a and 154a have an elastic restoring force, and the elastic restoring force acts in a direction that prevents swelling. In addition, the lower beading portions 152a and 154a of the cell cover 150' disperse or absorb the pressure when the battery cell 105 swells, thereby reducing the possibility of cracking the cell cover 150' and advantageously pressing the battery cell 105 to minimize the amount of swelling.

[0161] Next, with reference to Figs. 14 and 15, a cell cover according to another embodiment of the present invention will be described.

[0162] FIG. 14 is a diagram corresponding to FIG. 12 and showing another embodiment of the cell unit of FIG. 12, and FIG. 15 is a diagram corresponding to FIG. 12 and showing yet another embodiment of the cell unit of FIG. 12.

[0163] 14, a cell cover 150'' included in a cell unit 110'' according to another embodiment of the present invention may have a beading portion provided on the upper side. In other words, the cell cover 150'' of this embodiment includes upper beading portions 152b, 154b provided on the upper end portion of the first cover portion 152 connected to the third cover portion 156 and the upper end portion of the second cover portion 154 connected to the third cover portion 156.

[0164] That is, the cell cover 150'' includes a first cover portion 152 and a second cover portion 154 similar to the above-described cell cover 150, and the first cover portion 152 and the second cover portion 154 further include upper beading portions 152b, 154b formed between the third cover portion 156 and the battery cell 105. The upper beading portions 152b, 154b are curved inward toward the battery cell 105.

[0165] The upper beading portions 152b, 154b are provided at the upper ends of the first cover portion 152 and the second cover portion 154, and may be continuous along the longitudinal direction of the cell cover 150'', similar to the lower beading portions 152a, 154a. The upper beading portion 152b at the upper end of the first cover portion 152 and the upper beading portion 154b at the upper end of the second cover portion 154 may be provided symmetrically with respect to the center C of the cell cover 150'' shown in FIG. 14. As a result, the cell cover 150'' according to this embodiment may be configured such that the distance between the first cover portion 152 and the second cover portion 154 is narrow at the upper beading portions 152b, 154b.

[0166] According to the embodiment of FIG. 14, when the battery cell 105 is inserted into the cell cover 150'', a certain gap (spacing) is likely to be generated between the third cover part 156 and the upper edge part of the battery cell 105, as shown by "h2" in FIG. 14. In addition, the stress acting on the cell cover 150'' when the battery cell 105 swells is mainly concentrated on the connection parts between the third cover part 156 and the first cover part 152 and the second cover part 154, and this part is most likely to be damaged. However, according to the present embodiment, the stress when the battery cell 105 swells can be dispersed and absorbed, and damage to the cell cover 150'' can be effectively prevented.

[0167] In yet another embodiment, as shown in FIG. 15, a cell cover 150''' included in a cell unit 110''' according to yet another embodiment of the present invention may have beading portions provided on the upper and lower sides. That is, a cell cover 150''' according to yet another embodiment of the present invention includes upper beading portions 152b, 154b provided at an upper end of a first cover portion 152 connected to a third cover portion 156 and an upper end of a second cover portion 154 connected to the third cover portion 156, and lower beading portions 152a, 154a provided at a lower end of the first cover portion 152 and a lower end of the second cover portion 154. Such an embodiment of FIG. 15 can be said to have advantages of both the lower beading portion according to FIG. 12 and the upper beading portion according to FIG. 14.

[0168] Also, the battery pack 10' according to another embodiment of the present invention may further include a control module 18 accommodated in the internal space of the pack case 12'. Of course, the above-mentioned battery pack 10 may further include such a control module. Such a control module 18 may include a battery management system (BMS). The control module 18 may be mounted in the internal space of the pack case 12 and configured to comprehensively control the charging and discharging operation of the battery cells 105 and the data transmission and reception operation. The control module 18 may be arranged in pack units rather than in module units. More specifically, the control module 18 may be provided to control the charging and discharging state, power state, and performance state of the battery cells 105 using the pack voltage and pack current. The control module 18 estimates the state of the battery cells 105 in the battery pack 10' and manages the battery pack 10' using the estimated state information. For example, the control module estimates and manages state information of the battery pack 10', such as the state of charge (SOC), state of health (SOH), maximum input / output power allowance, and output voltage of the battery pack 10'. Such status information can be used to control the charging or discharging of the battery pack 10', and can also be used to estimate the time to replace the battery pack 10'.

[0169] The battery pack 10 as well as the battery pack 10' may further include a battery cutoff unit 19. The battery cutoff unit 19 may be configured to control electrical connection of the battery cells 105 to manage the power capacity and function of the battery packs 10, 10'. To this end, the battery cutoff unit 19 may include a power relay, a current sensor, a fuse, and the like. The battery cutoff unit 19 is also a component that is arranged in a pack unit rather than in a module unit, and various cutoff units known at the time of filing of the present invention may be employed.

[0170] In addition, the battery pack 10, 10' according to the present invention may further include various battery pack components known at the time of filing of the present invention. For example, the battery pack 10, 10' according to the embodiment of the present invention may further include a manual service disconnector (MSD) that allows an operator to manually remove a service plug to cut off the power supply. In addition, the battery pack 10, 10' may further include a flexible bus bar or cable for connecting a plurality of battery assemblies 100, 100' to each other.

[0171] Meanwhile, the battery assemblies 100, 100' according to various embodiments of the present invention can be applied to a battery pack, as well as to a battery module having a separate case and housed in a battery pack or a rack of an energy storage system (ESS).

[0172] FIG. 16 is a diagram illustrating a vehicle V according to an embodiment of the present invention.

[0173] As shown in FIG. 16, an automobile V according to one embodiment of the present invention may include a battery pack 10, 10' including at least one battery assembly according to any one of the various embodiments described above.

[0174] In this manner, the battery packs 10, 10' installed in the automobile V can provide the electric energy required for various operations of the automobile V. Here, the automobile V may include a specific automobile that uses electricity as a driving source, such as an electric automobile or a hybrid automobile. Furthermore, the automobile V may further include various other components included in an automobile, such as a vehicle body and a motor, in addition to the battery packs 10, 10' according to the present invention.

[0175] The battery packs 10, 10' may be disposed at predetermined positions within the vehicle V. The battery packs 10, 10' may be used as a source of electric energy for providing driving force to a motor of the electric vehicle to drive the vehicle V. In this case, the battery packs 10, 10' have a high nominal voltage of 100 V or more.

[0176] The battery packs 10, 10' may be charged or discharged by an inverter in response to driving of a motor and / or an internal combustion engine. The battery packs 10, 10' may be charged by a regenerative charging device coupled to a brake. The battery packs 10, 10' may be electrically connected to a motor of the automobile V via an inverter.

[0177] Meanwhile, in this specification, terms indicating directions such as up, down, left, right, front, and back are used, but these terms are merely for convenience of explanation, and it will be obvious to those skilled in the art of the present invention that they may change depending on the position of the object in question, the position of the observer, etc.

[0178] The present invention has been described above with reference to specific embodiments. However, it will be apparent to those skilled in the art that various modified embodiments can be realized within the technical scope of the present invention. Therefore, the embodiments disclosed above should be considered from an explanatory perspective, not a limiting one. That is, the true technical scope of the present invention is set forth in the claims, and all differences within the scope equivalent thereto should be interpreted as being included in the present invention. [Explanation of symbols]

[0179] 10, 10' Battery Pack 12 pack case 100 Battery Assembly 105 Battery Cells 107 Electrode Lead 110, 110' cell unit 150, 150', 150'', 150'' Cell Cover 152 First cover part 154 Second cover part 156 Third cover part 152a, 154a Lower beading part 152b, 154b Upper beading part 200, 200' Heatsink 210 Fixed groove 220 Thermal Resin 230 Air Layer DV1, DV2 vent space V Automobile

Claims

1. A battery assembly including a plurality of cell units; a pack case that houses the battery assembly in an internal space; Including, Each cell unit includes at least one battery cell and a cell cover that at least partially encloses an exterior of the at least one battery cell; The battery pack has a vent space between the cell cover and the battery cell.

2. 2. The battery pack according to claim 1, wherein the cell cover is configured to support the at least one battery cell in an upright position.

3. The battery pack according to claim 1 , wherein the cell cover partially encases the battery cell to form an opening where at least one side of the encased battery cell is exposed toward the pack case.

4. The battery pack according to claim 1 , wherein the cell cover is formed of a single bent plate.

5. The battery pack according to claim 1 , wherein the cell cover includes an insulating coating layer on an inner surface thereof.

6. The cell cover is a first cover portion covering one side surface of the at least one battery cell; a second cover portion covering the other side surface of the at least one battery cell; 2 . The battery pack according to claim 1 , further comprising: a third cover portion connecting the first cover portion and the second cover portion and covering one side edge portion of the at least one battery cell.

7. The battery pack according to claim 6 , wherein the vent space is provided between the battery cell and the third cover portion.

8. The battery pack according to claim 6 , wherein the at least one battery cell is adhesively fixed to inner surfaces of the first cover portion and the second cover portion.

9. 7. The battery pack of claim 6, wherein an end of the first cover part that is not connected to the third cover part and an end of the second cover part that is not connected to the third cover part form an opening through which one side of the battery cell is exposed toward the pack case.

10. 7. The battery pack according to claim 6, wherein the at least one battery cell is disposed between the first cover portion and the second cover portion of the cell cover, and is disposed at a distance from the third cover portion so that a predetermined space is formed between the third cover portion and the at least one battery cell.

11. The battery pack according to claim 6 , wherein a vertical length of the first cover portion and the second cover portion of the cell cover is longer than a vertical length of the at least one battery cell.

12. The battery pack according to claim 6 , further comprising a heat sink in thermal contact with the cell unit to cool the cell unit.

13. The battery pack of claim 12 , wherein the cell cover is in contact with the heat sink.

14. 13. The battery pack according to claim 12, wherein both ends of the cell cover extend toward the heat sink and extend longer than ends of the at least one battery cell such that a predetermined space is formed between the at least one battery cell disposed between the first cover part and the second cover part and the heat sink.

15. The battery pack according to claim 14 , wherein the heat sink has fixing grooves into which both ends of the cell cover are inserted and fixed.

16. 10. The battery pack according to claim 9, wherein the first cover portion and the second cover portion further include a lower beading portion formed at an end adjacent to the opening and indented inward toward the battery cell.

17. The battery pack according to claim 16 , wherein the lower beading portion is formed continuously along a longitudinal direction of the cell cover.

18. 17. The battery pack according to claim 16, wherein the lower beading portion of the first cover portion and the lower beading portion of the second cover portion are provided symmetrically with respect to a center of the cell cover.

19. 7. The battery pack of claim 6, wherein the first cover portion and the second cover portion further include an upper beading portion formed between the third cover portion and the battery cell and indented inward toward the battery cell.

20. The battery pack according to claim 19 , wherein the upper beading portion is formed continuously along a longitudinal direction of the cell cover.

21. 21. The battery pack according to claim 20, wherein the upper beading portion of the first cover portion and the upper beading portion of the second cover portion are provided symmetrically with respect to a center of the cell cover.

22. 17. The battery pack according to claim 16, wherein the first cover portion and the second cover portion further include an upper beading portion formed between the third cover portion and the battery cell and indented inward toward the battery cell.

23. 23. A motor vehicle comprising a battery pack according to any one of claims 1 to 22.

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