Battery module case accommodating stack of battery cells

Abstract

The present disclosure relates to a case configured to accommodate a battery cell stack of a battery module, and more particularly, to a frame included in the case, and the frame includes: a cutout portion including a cutout portion; a cutout portion formed on an inner surface of the frame adjacent to a bat-ear protruding vulnerable portion provided at a corner of each battery cell included in the battery cell stack to avoid interference with the protruding vulnerable portion; and a double injection molded portion joined with the machined surface of the cut-out portion by double injection, having a shape recessed lower than the inner surface to cover the cut-out portion while avoiding interference with the vulnerable portion, and formed to constitute a part of the inner surface; also provided are a case including the frame, a battery module including the case, a battery pack including the battery module, a vehicle including the battery pack, and the like.

Description

Technical Field

[0001] This application claims the benefit of priority from Korean Patent Application No. 10-2022-0065622 filed on May 27, 2022 in the Korean Intellectual Property Office, the disclosure of which is incorporated herein by reference in its entirety.

[0002] The present disclosure relates to a battery module case accommodating a battery cell stack, and more particularly, to a battery module case having improved space utilization, insulation performance, and economic feasibility of a manufacturing process. Background Art

[0003] Secondary batteries, which are applied to various product groups and have electrical characteristics such as high energy density, are widely used in electric vehicles (EVs), hybrid vehicles (HVs), energy storage systems, etc. driven by electric drive sources, as well as portable devices. Secondary batteries have attracted attention as a new energy source that promotes environmental protection and energy efficiency due to their main advantages of completely generating no byproducts with the use of energy and significantly reducing the use of fossil fuels.

[0004] Although each small mobile device uses one or two to four battery cells, medium and large devices such as cars require high power and large capacity. Therefore, medium and large battery modules in which a plurality of battery cells are electrically connected are used.

[0005] The middle and large battery modules are preferably manufactured with the smallest possible size and weight, and thus square batteries, pouch type batteries, etc., which are stacked with high integration and have relatively small weight capacity, are mainly used as battery cells of the middle and large battery modules.

[0006] Meanwhile, in order to protect the battery cell stack from external impact, heat, or vibration, the battery module may include a frame member whose front and rear surfaces are opened to accommodate the battery cell stack in an internal space.

[0007] Figure 1 and Figure 2 2 are perspective views and exploded perspective views showing a battery module having a U-shaped frame with its upper portion and front and rear surfaces opened after assembly and before assembly, respectively. Referring to these drawings, a battery module 0 having a U-shaped frame includes a battery cell stack 1 configured by stacking battery cells 11 and a housing configured to accommodate the battery cell stack 1, and the housing includes a frame 2 configured to cover a lower portion and both sides thereof in a width direction Y1, an upper plate 10 configured to cover an upper portion thereof, and a pair of end plates 20 configured to cover both sides thereof in a length direction X1. The frame 2 has a shape connecting a bottom surface 21 and two side walls in a width direction.

[0008] The battery cell stack 1 is an assembly in which a plurality of pouch-type battery cells 11 are stacked and assembled and accommodated in a case such that a normal direction Z2 of each battery cell 11 matches a width direction of the case.

[0009] Figure 3 is a perspective view showing a unit soft-pack type battery cell 11. Referring to the figure, the battery cell 11 has a structure in which an electrode assembly, an electrode tab and an electrode lead are contained in a soft pack made of a material mainly coated with an insulating material on both surfaces of a metal sheet, and the electrode lead has a portion protruding to the outside of the soft pack in the length direction X2. The soft pack is folded with the length direction as an axis, and three surfaces other than the folded portion are heat-welded and sealed. In this case, a vulnerable portion 11b is formed at two corners in the length direction of the soft pack between one end in the width direction of the soft pack and two ends of the soft pack sealed on the lead film, and the vulnerable portion 11b protrudes from one end of the soft pack on the side where the folded portion is located to one side in the width direction Y2 by extrusion, and the vulnerable portion 11b is also called a bat ear. The vulnerable portion 11b has a shape protruding from the battery cell 11 toward one side in the width direction, so there is a possibility of interference with the inner surface of the frame 2 during the assembly of the battery module 0, and when such interference exists, the sealing of the soft pack may be deteriorated and the insulation may be reduced. In addition, the spacing distance between the battery cell stack 1 and the frame 2 increases due to the protruding shape of the vulnerable portion 11 b , so a thicker thermally conductive resin layer needs to be provided between the battery cell stack 1 and the frame 2 to assist the cooling of the battery cells 11 , which is uneconomical.

[0010] Meanwhile, in order to solve this problem, in the related art, attempts are made to avoid interference between the vulnerable portion 11b and the frame 2 while increasing space utilization by machining a portion of the bottom surface 21 of the frame 2 that may interfere with the vulnerable portion 11b to form a step portion having a height less than that of other portions of the bottom surface 21, and then attach an insulating tape to the step portion to prevent insulation failure. However, the attachment of the insulating tape is an additional work after machining the step portion, so the process is troublesome and uneconomical, and defects may occur because the attachment is performed manually. Summary of the invention

[0011] Technical issues

[0012] The present disclosure is made in view of the aforementioned problems of the related art, and an object of the present disclosure is to provide a battery module case capable of ensuring insulation performance while reducing interference with a vulnerable portion provided on a battery cell.

[0013] Another object of the present disclosure is to maximize space utilization by providing a frame having a shape corresponding to the protruding shape of the vulnerable portion, and to reduce the thickness of a thermally conductive resin layer disposed between the battery cell stack and the frame by reducing the spacing distance therebetween, thereby ensuring economic feasibility.

[0014] Still another object of the present disclosure is to provide a housing that simplifies conventional complicated processes of machining a step portion and attaching an insulating tape by providing a frame that does not interfere with a vulnerable portion and ensures insulating performance, and exhibits stable performance with a cost-saving process.

[0015] Yet another object of the present disclosure is to reduce the possibility of defects occurring due to the conventional insulating tape attaching process being a manual process.

[0016] Still another object of the present disclosure is to provide a case produced by the above-mentioned economical process and exhibiting anti-interference performance and insulation performance, a battery module including the case, a battery pack including the battery module, and a vehicle including the battery pack.

[0017] The various aspects of the present disclosure are not limited to the above aspects, and other aspects and advantages not mentioned above can be clearly understood from the following description, and can be more clearly understood from the aspects set forth herein. In addition, the various aspects and advantages of the present disclosure can be realized via the devices described in the appended claims and combinations thereof.

[0018] Technical Solution

[0019] In order to achieve the above-mentioned purpose, the present disclosure provides a shell configured to accommodate a battery cell stack in a battery module, wherein a cut-out portion is formed by cutting out a part that may interfere with an end portion of a vulnerable portion that is arranged to protrude from one side of each battery cell in a width direction, and the cut-out portion is covered by a double injection molded portion made of a double injection synthetic resin.

[0020] The shell may include a U-shaped frame connecting the bottom surface and two side walls in the width direction (Y1), an upper plate covering the upper part, and end plates covering both sides in the length direction (X1), and the bottom surface and the two side walls of the frame may be a single curved member or may be joined to each other as separate members.

[0021] The frame may be made of sheet metal and may be manufactured by plastic deformation through stamping, but manufacturing from other materials or by other machining methods is not excluded.

[0022] The cutout portion may be preformed in a conventional frame by punching and cutting, or may be preformed when cutting a metal plate that is plastically deformed by punching. The cutout portion may be formed by any method as long as it is formed in a shape that cuts out a portion of the frame and is formed at a portion that may interfere with an end of a vulnerable portion of a battery cell in the frame to prevent interference.

[0023] A cutout portion may be formed on a bottom surface of the frame.

[0024] The cutout portion may be machined into a shape that leaves a portion of the thickness of the bottom surface of the frame and is recessed into the bottom surface, or may be cut into a shape that completely penetrates the bottom surface.

[0025] The cutout portion may be formed at one end portion or both end portions in the length direction of the frame.

[0026] The cutout portion may be formed at one end portion in the length direction of the frame with a corner portion where both side walls of the frame meet the bottom surface as a boundary in the width direction.

[0027] The double injection molded part may be made of insulating synthetic resin.

[0028] The two-shot molded part may be made of an insulating and thermally conductive synthetic resin.

[0029] The double injection molded portion may be joined to the machined surface of the cut-away portion by double injection molding.

[0030] The double injection molding part may have a shape that is more concave than the bottom surface of the frame on which the cutout portion is formed. At the same time, a thermally conductive resin layer may be provided between the frame and the battery cell stack. The thickness of the thermally conductive resin layer may be determined according to the spacing distance between the battery cell stack and the frame. When the thickness of the thermally conductive resin layer is too thick, economic feasibility is reduced, and thus the concave shape may be formed to have a step corresponding to the protrusion degree of the vulnerable portion to reduce the spacing distance.

[0031] The thickness of the double injection molded part may be smaller than, larger than, or equal to the thickness of the bottom surface.

[0032] The lower surface of the two-shot molded part may form a step with the lower surface of the bottom surface or may be continuous without a step.

[0033] The housing according to one embodiment of the present disclosure includes: a U-shaped frame formed by plastic deformation of a metal plate; a cutout portion formed at one end in the length direction of the frame with two corners where the bottom surface and two side walls meet as its width direction boundary and penetrating the bottom surface; a double injection molded portion connected to the machined surface of the cutout portion, and the thickness of the double injection molded portion is less than the thickness of the bottom surface. The lower surface of the double injection molded portion has the same height as the lower surface of the bottom surface and is continuous without a step, and the upper surface of the double injection molded portion is more concave downward than the upper surface of the bottom surface, so that the upper surface of the double injection molded portion and the upper surface of the bottom surface are formed to produce a step.

[0034] According to another embodiment of the present disclosure, the housing includes: a U-shaped frame formed by plastic deformation of a metal plate; a cutout portion formed at one end in the length direction of the frame with two corners where the bottom surface and two side walls meet as its width direction boundary and penetrating the bottom surface; a double injection molded portion connected to the machined surface of the cutout portion, and having a thickness equal to that of the bottom surface. The entire double injection molded portion protrudes downward further than the bottom surface, so that the double injection molded portion forms a step with both the upper surface and the lower surface of the bottom surface.

[0035] The double injection molded portion may be formed to cover a portion of a bottom surface of an inner side of the machined surface of the cut-away portion.

[0036] According to another embodiment of the present disclosure, the housing includes: a U-shaped frame formed by plastic deformation of a metal plate; a cutout portion formed at one end in the length direction of the frame with two corners where the bottom surface meets two side walls as its boundaries in the width direction and penetrating the bottom surface; a double injection molded portion connected to a machined surface of the cutout portion and a portion of the bottom surface inside the boundary of the cutout portion, and the thickness of the double injection molded portion is less than the thickness of the bottom surface. The lower surface of the double injection molded portion has the same height as the lower surface of the bottom surface and is continuous without a step, and the upper surface of the double injection molded portion is more concave downward than the upper surface of the bottom surface, so that the upper surface of the double injection molded portion and the upper surface of the bottom surface are formed to produce a step.

[0037] These technical solutions may be applied to a battery module housing according to the present disclosure, a battery module including the battery module housing, a battery pack including the battery module, a vehicle on which the battery pack is mounted, and the like.

[0038] Beneficial Effects

[0039] According to the present disclosure, by providing a cutout portion obtained by cutting out a portion of the frame that may interfere with a vulnerable portion of each battery cell of a battery cell stack accommodated in the frame included in the battery module case, interference between the vulnerable portion and the frame may be minimized.

[0040] According to another aspect of the present disclosure, by providing a cut-out portion corresponding to the vulnerable portion, the spacing distance between the frame and the battery cell stack can be reduced, thereby maximizing space utilization, and the thickness of the thermally conductive resin layer provided between the frame and the battery cell stack can be reduced, thereby improving the economic feasibility of the production of the battery module.

[0041] According to still another aspect of the present disclosure, by covering the cut-away portion with a double injection-molded portion made of an insulating synthetic resin, the vulnerable portion may be electrically insulated from the frame, thereby improving the stability of the battery module.

[0042] According to another aspect of the present disclosure, since the step portion is prepared only by a two-material injection molding process and the insulation treatment is performed at the same time instead of the conventional process of first preparing the step portion and then performing the insulation treatment through a two-step process of machining the step portion and attaching an insulating tape, economic feasibility in the process can be provided.

[0043] According to still another aspect of the present disclosure, a manual process of attaching an insulating tape is replaced by an automated process of double injection molding, thereby preventing defects of a battery module due to defects of the insulating tape.

[0044] In addition to the above-described effects, various other effects may be produced according to the present disclosure, and descriptions of these effects are provided with reference to the various embodiments, or descriptions of effects that are easily predicted by a person of ordinary skill in the art are omitted, etc. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figure 1 is a perspective view showing an assembled state of a battery module including a U-shaped frame.

[0046] Figure 2 is an exploded perspective view showing a state before a battery module including a U-shaped frame is assembled.

[0047] Figure 3 is a perspective view showing one unit pouch-type battery cell.

[0048] Figure 4 is a perspective view showing a U-shaped frame according to one embodiment of the present disclosure.

[0049] Figure 5 is an enlarged side cross-sectional view showing that the thickness of a double injection molded portion of one embodiment of the present disclosure is smaller than the thickness of a bottom surface of a frame.

[0050] Figure 6 is an enlarged side cross-sectional view showing that the thickness of a double injection molded portion of one embodiment of the present disclosure is equal to the thickness of a bottom surface of a frame.

[0051] Figure 7 is an enlarged side cross-sectional view showing a portion of a bottom surface on the inner side of a boundary of a double injection molded part covering a cut surface of one embodiment of the present disclosure.

[0052] Figure 8 A vehicle mounted with a battery pack including a battery module having an improved case is shown.

[0053] [reference numerals]

[0054] 0: Battery module

[0055] 10: On the board

[0056] 20: End plate

[0057] 1: Battery cell stack

[0058] 11: Battery Cell

[0059] 11b: vulnerable part / bat ears

[0060] 2: Framework

[0061] 21: Bottom surface

[0062] 22: Resection

[0063] 22m: Machined surface

[0064] 23: Double injection molding department

[0065] V: Vehicle

[0066] P: Battery Pack

[0067] X1: Length direction of the frame (bottom surface)

[0068] Y1: Width direction of the frame (bottom surface)

[0069] Z1: height direction of the frame

[0070] X2: length direction of battery cell

[0071] Y2: width direction of battery cell

[0072] Z2: Height direction of battery cell (normal direction) DETAILED DESCRIPTION

[0073] The above aspects, features and advantages are described in detail below with reference to the accompanying drawings, so that a person skilled in the art in the art to which the present disclosure belongs can easily realize the technical spirit of the present disclosure. In the present disclosure, if it is considered that a detailed description of a known technology related to the disclosed subject matter will make the main points of the present disclosure unnecessarily obscure, the detailed description is omitted. In the following, preferred embodiments according to the present disclosure are described in detail with reference to the accompanying drawings. In the accompanying drawings, the same reference numerals may represent the same or similar components.

[0074] The terms "first", "second", etc. are used herein only to distinguish one component from another component. Therefore, the components should not be limited by the terms. Of course, unless otherwise specified, the first component may be the second component.

[0075] Throughout the disclosure, unless explicitly stated otherwise, each component may be provided as a single component or as a plurality of components.

[0076] When any component is described as being located "on the upper part (or lower part)" or "on (or below)" another component, any component may be directly located above (or below) the other component, however, additional components may be interposed between any component and the other component located above (or below) the any component.

[0077] When any component is described as being “connected,” “coupled,” or “coupled” to another component, the one component may be directly connected or coupled to the other component, however, an additional component may be “interposed” between the two components, or the two components may be “connected,” “coupled,” or “coupled” through the additional component.

[0078] Unless expressly stated otherwise, the singular forms "a", "an" and "the" are intended to include the plural forms as well. It should be understood that the terms "include", "comprises", etc. set forth herein should not be interpreted as necessarily including all of the components or steps, but may be interpreted as excluding some of the components or steps or may be interpreted as including additional components or steps.

[0079] Throughout the disclosure, as used herein, the phrase "A and / or B" may mean A, B, or A and B, and the phrase "C to D" may mean C or more and D or less, unless stated otherwise.

[0080] For the convenience of description, in this specification, taking the battery module as a reference, the direction passing through the two end plates of the battery module and parallel to the bottom surface of the frame is referred to as the length direction X1, the direction perpendicular to the plane formed by the individual battery cells included in the battery cell stack and parallel to the bottom surface of the frame is referred to as the width direction Y1, and the normal direction of the bottom surface of the frame is referred to as the height direction Z1.

[0081] In addition, in this specification, with the battery cell as a reference, the direction passing through the two electrode leads and parallel to the battery cell is referred to as the length direction X2, the direction perpendicular to the length direction and parallel to the battery cell is referred to as the width direction Y2, and the direction corresponding to the normal direction of the battery cell is referred to as the normal direction or height direction Z2.

[0082] Hereinafter, exemplary embodiments of the present disclosure will be described with reference to the accompanying drawings.

[0083] Figure 1 and Figure 2 2 are perspective views and exploded perspective views respectively showing a battery module 0 having a U-shaped frame 2 with its upper portion and front and rear surfaces opened after assembly and before assembly. Referring to these drawings, the battery module 0 having the U-shaped frame 2 may include a battery cell stack 1 configured by stacking battery cells 11 and a housing configured to accommodate the battery cell stack 1, and the housing may include a frame 2 configured to cover a lower portion and both sides thereof in a width direction Y1, an upper plate 10 configured to cover an upper portion thereof, and a pair of end plates 20 configured to cover both sides thereof in a length direction X1.

[0084] The frame 2 may have a U-shape connecting the bottom surface 21 and the two side walls in the width direction. The U-shaped frame 2 may be formed by joining a plate forming the bottom surface 21 with a plate forming each of the two side walls, or may be formed by bending one plate at two corners where the bottom surface 21 meets the two side walls.

[0085] The frame 2 may be made of a metal plate and may be manufactured by plastically deforming the metal plate by punching. However, any material and manufacturing process that can be formed into a frame having a U-shape as described above may be used.

[0086] The frame 2 may be assembled with the end plates 20 and the upper plate 10 to form a housing. The assembly may be performed by joining such as welding or by other methods such as friction fitting or bolting.

[0087] Meanwhile, the battery cell stack 1 is an assembly of stacking and assembling a plurality of soft-pack type battery cells 11, and may include bus bars to which electrode leads (positive and negative leads) extending and protruding outside the battery cells 11 are connected in the case where the polarities are the same as each other or the polarities are different from each other. The bus bars are respectively connected to the end plates 20 to electrically connect the battery cell stack 1 to the outside.

[0088] The battery cell stack 1 can be accommodated in the housing so that the normal direction Z2 of each battery cell 11 matches the width direction of the housing. At this time, the battery cell stack 1 can be accommodated in the housing so that the vulnerable portion 11b of the battery cell 11 described below faces the bottom surface 21 of the frame 2 in the width direction.

[0089] Figure 3 is a perspective view showing one unit soft-pack type battery cell 11. Referring to the figure, the battery cell 11 has a structure in which an electrode assembly, an electrode tab, and an electrode lead are accommodated in a soft pack mainly made of a material in which both surfaces of a metal sheet are coated with an insulating material, and the electrode lead portion extends and protrudes to the outside of the soft pack.

[0090] The electrode assembly has a structure in which the positive plate and the negative plate are stacked multiple times, and the separator is inserted between the positive plate and the negative plate. The electrode tabs can be configured to extend and protrude from the positive plate and the negative plate and overlap each other with the same polarity. The electrode lead is welded and electrically connected to the electrode tab, and a portion of the electrode lead extends through the lead film surrounding the electrode lead and protrudes to the outside of the soft pack in the length direction X2, so that the electrode assembly can be electrically connected to the outside.

[0091] The soft pack is formed of a metal sheet coated with an insulating material, and the shape of the soft pack is formed by folding the metal sheet having a symmetrical rectangle around its symmetry axis (after folding, becoming one end in the width direction) and heat-melting and sealing the remaining three side portions except the folded portion. At this time, the two corners between the folded portion of one end in the width direction and the two end portions in the length direction adjacent to the folded portion are squeezed in the sealing process to form a vulnerable portion (bat ear) 11b having a shape protruding from the corner to one side in the width direction. Since the vulnerable portion 11b has a protruding shape, the vulnerable portion 11b may interfere with the frame 2. When such interference occurs, this may result in poor sealing and / or insulation performance of the vulnerable portion 11b.

[0092] At the same time, a thermally conductive resin layer may be provided between the battery cell stack 1 and the frame 2 for the cooling effect of the battery cell stack 1. The cooling effect refers to that the thermally conductive resin layer between the battery cell stack 1 and the frame 2 conducts the heat generated by the battery cell stack 1 to the frame 2 to easily discharge the heat to the outside to prevent the battery performance from being deteriorated due to the separation space between the battery cell stack 1 and the frame 2 used as the heat insulating portion, and the heat generated in the battery cell stack 1 cannot be effectively discharged to the outside of the battery module. In this case, as the separation space increases, it is inevitable to form the thermally conductive resin layer thicker, thereby reducing the economic feasibility of production. However, when the battery cell stack 1 is accommodated in the frame 2 having a flat inner surface, due to the protruding shape of the vulnerable portion 11b, in the remaining portion other than the protruding portion of the vulnerable portion 11b, the spacing distance between the battery cell stack 1 and the frame 2 is excessively increased, so that the space utilization may be reduced and the thermally conductive resin layer may be too thick.

[0093] Therefore, the present disclosure provides a battery module case having a structure in which a cutout portion 22 formed by cutting off a portion that may interfere with a protruding end of a vulnerable portion 11 b is provided in a frame 2 and a double injection molded portion 23 covers the cutout portion 22 .

[0094] Figure 4 1 is a perspective view showing a U-shaped frame 2 according to an embodiment of the present disclosure. Referring to the figure, in the U-shaped frame 2, a portion interfering with the end of the vulnerable portion 11b is cut away to form a cut-away portion 22, and a double injection molded portion 23 formed by double injection molding of a synthetic resin covers the cut-away portion 22.

[0095] The cutout portion 22 may be formed later by punching the conventional frame 2, or may be formed in advance in a process of cutting a metal plate that is plastically deformed into the shape of the frame 2 by punching. The method of forming the cutout portion 22 may be changed as long as its shape is such that a part of the frame 2 is cut out to avoid interference between the vulnerable portion 11b and the frame 2.

[0096] The cutout portion 22 may be formed on the bottom surface 21 of the frame 2. For example, the cutout portion 22 may be formed at one end in the length direction of the bottom surface 21 of the frame 2. Alternatively, the cutout portion 22 may be formed on the side wall of the frame 2. The position of the cutout portion 22 may be any position as long as the position may interfere with the vulnerable portion 11b. For example, the position of the cutout portion 22 may be an edge portion of the frame 2 or the inner side of one surface of the frame 2.

[0097] The cutout portion 22 may be formed in a shape that is recessed into the bottom surface 21 or the inner side surface of the frame 2 and leaves a portion of its thickness, or may be formed in a surface that is completely penetrated. For example, the cutout portion 22 may be formed by partially cutting off one end or both ends in the length direction of the bottom surface 21 of the frame 2 to completely penetrate. By trimming with punching or the like, the cutout portion 22 in a form that completely penetrates the frame 2 may be formed at a low cost.

[0098] The cutout portion 22 may be formed on the bottom surface 21 of the frame 2 with two corners where the bottom surface 21 meets two side walls in the width direction as boundaries in the width direction thereof.

[0099] The double injection molded part 23 may be made of a synthetic resin and may be formed by double injection molding to be connected to the machined surface 22m of the cutout part 22 and to cover the cutout part 22. The term "covering" may mean that the double injection molded part 23 fills the space of the cutout part 22 generated due to the inner surface of the frame 2 being recessed or penetrating to the outside and constitutes a part of the inner wall of the frame 2.

[0100] In addition to covering the cutout 22, the double injection molded portion 23 may extend and protrude to the outside. For example, the double injection molded portion 23 may cover the cutout 22 formed at one end in the length direction of the bottom surface 21 of the frame 2, and may also extend and protrude beyond the side wall of the frame 2 in the length direction.

[0101] The double injection molded portion 23 may not completely cover the concave or through space of the cutout portion 22, and may have a concave or through shape at one end thereof. The concave or through portion of the double injection molded portion 23 may be formed so that a corresponding portion of another member such as the end plate 20 may cover the concave or through portion.

[0102] The double injection molded portion 23 may have a shape that is more concave than the inner surface of the frame 2 on which the cutout portion 22 is formed. The term "concave" may mean that a depth is formed relative to the inner surface of the frame 2 except for the cutout portion 22 in the surface on which the cutout portion 22 is formed. For example, the concave portion may be the same shape as a groove or a step portion. Since the concave shape is provided, it is possible to prevent the phenomenon that the vulnerable portion 11b of the battery cell 11 interferes with the double injection molded portion 23 even if the double injection molded portion 23 covers the cutout portion 22.

[0103] The degree of depression of the double-molded part 23 may be determined to form a step corresponding to the degree of protrusion of the vulnerable part 11b. Since the double-molded part 23 is depressed relative to the inner surface of the frame 2 as much as the vulnerable part 11b protrudes, the spacing distance between the battery cell stack 1 and the frame 2 can be reduced, so the thermally conductive resin layer can be thinned to become economical, or even without the thermally conductive resin layer, the heat generated by the battery cell stack 1 can be easily conducted to the frame 2 and discharged to the outside.

[0104] A concave shape or step may be formed in the width direction and / or the length direction along the machined surface 22m of the cutout portion 22. For example, as in the embodiment to be described below, the double injection molded portion 23 may have a shape that is more concave than the bottom surface 21 with reference to the boundary in the width direction of the cutout portion 22 and the boundary in the length direction of the cutout portion 22.

[0105] The double injection molded part 23 may be made of an insulating synthetic resin. In this case, even when the sealing or insulating properties of the vulnerable part 11b deteriorate or interference occurs between the vulnerable part 11b and the double injection molded part 23, the insulating properties of the double injection molded part 23 can be maintained.

[0106] The double injection molded part 23 is made of a thermally conductive synthetic resin or may be made of a thermally conductive synthetic resin that also serves as an insulating synthetic resin. In this case, the heat generated from the battery cell stack 1 can also be conducted to the double injection molded part 23 to be easily discharged to the outside.

[0107] In the embodiment, the double injection molded part 23 is exemplified as being manufactured by double injection molding, but the double injection molded part 23 may also be formed by insert injection molding, etc. That is, the double injection molded part itself does not limit the manufacturing method of the corresponding component to be double injection molding.

[0108] Figure 5 2 is an enlarged side cross-sectional view showing one embodiment of the present disclosure. Referring to the figure, the double injection molded portion 23 may have a shape more concave than the bottom surface 21 by being formed with a thickness smaller than that of the bottom surface 21 of the frame 2. At this time, the lower surface of the bottom surface 21 and the lower surface of the double injection molded portion 23 may be continuous without a step. In this case, when placed on a flat ground, the frame 2 may maintain a stable structure despite Figure 5 Only the side surface, i.e., only the cross section in the width direction of the frame 2 is shown, and when the machined surface 22m of the cutout portion 22 is also formed in the length direction, the front surface, i.e., the cross section in the length direction of the frame 2 is the same as described above.

[0109] For example, refer to Figure 4 and Figure 5 , a housing according to one embodiment of the present disclosure includes a U-shaped frame 2 formed by plastic deformation of a metal plate, a cutout portion 22 is formed at one end in the length direction of the frame 2 with two corners where a bottom surface 21 meets two side walls as its boundaries in the width direction and penetrates the bottom surface 21, a double injection molded portion 23 is connected to a machined surface 22m of the cutout portion 22, and a thickness of the double injection molded portion 23 is less than a thickness of the bottom surface 21. The lower surface of the double injection molded portion 23 and the lower surface of the bottom surface 21 have the same height and are continuous without a step, and the upper surface of the double injection molded portion 23 is more concave downward than the upper surface of the bottom surface 21, so that the upper surface of the double injection molded portion 23 and the upper surface of the bottom surface 21 are formed to produce a step equal to the protrusion degree of the vulnerable portion 11b of the battery cell 11.

[0110] Figure 6is an enlarged side cross-sectional view showing another embodiment of the present disclosure. Referring to the figure, the double injection molded part 23 can be formed so that its thickness is equal to the thickness of the bottom surface 21 of the frame 2, but the double injection molded part 23 itself protrudes downward relative to the bottom surface 21, so that the upper surface of the double injection molded part 23 has a negative step with the upper surface of the bottom surface 21 as a reference, and the lower surface of the double injection molded part 23 has a positive step with the lower surface of the bottom surface 21 as a reference. The negative step or the positive step means that the upper surface or the lower surface of the double injection molded part 23 is concave or protrudes more than the upper surface or the lower surface of the bottom surface 21. In this way, the double injection molded part 23 or the bottom surface 21 can be formed into a concave shape without interference, without being unnecessarily thickened or thinned to the extent that its strength cannot be maintained. Although Figure 6 Only the side surface, i.e., only the cross section in the width direction of the frame 2 is shown, and when the machined surface 22m of the cutout portion 22 is also formed in the length direction, the front surface, i.e., the cross section in the length direction of the frame 2 is the same as described above.

[0111] For example, refer to Figure 4 and Figure 6 , a housing according to an embodiment of the present disclosure includes a U-shaped frame 2 formed by plastic deformation of a metal plate, a cutout portion 22 is formed at one end in the length direction of the frame 2 with two corners where a bottom surface 21 meets two side walls as its width direction boundary and penetrates the bottom surface 21, a double injection molded portion 23 is connected to the machined surface of the cutout portion 22, and the thickness of the double injection molded portion 23 is equal to the thickness of the bottom surface 21. The entire double injection molded portion 23 protrudes downward further than the bottom surface 21, so that both the upper and lower surfaces of the double injection molded portion 23 and the bottom surface 21 form a step equal to the protrusion of the vulnerable portion 11b of the battery cell 11.

[0112] Figure 7 2 is an enlarged side cross-sectional view showing another embodiment of the present disclosure. Referring to the figure, in addition to covering the cutout portion 22, the double injection molded portion 23 can also cover a portion of the bottom surface 21 inside the boundary of the cutout portion 22. Therefore, it is possible to prevent the insulation or sealing of the battery cell 11 from being damaged due to the generation of a sharp step portion at the boundary portion of the concave portion, and to prevent the insulation performance from being reduced. Although Figure 7 Only the side surface is shown, that is, only the cross section in the width direction of the frame 2 is shown, and when the machined surface 22m of the cutout portion 22 is also formed in the length direction, the front surface (that is, the cross section in the length direction of the frame 2) is the same as above.

[0113] For example, refer to Figure 4 and Figure 7, a housing according to one embodiment of the present disclosure includes a U-shaped frame 2 formed by plastic deformation of a metal plate, a cutout portion 22 is formed at one end in the length direction of the frame 2 with two corners where a bottom surface 21 meets two side walls as its boundaries in the width direction and penetrates the bottom surface 21, a double injection molded portion 23 is connected to a machined surface 22m of the cutout portion 22 and a portion of the bottom surface 21 inside the boundary of the cutout portion 22, and a thickness of the double injection molded portion 23 is smaller than that of the bottom surface 21. The lower surface of the double injection molded portion 23 and the lower surface of the bottom surface 21 have the same height and are continuous without a step, and the upper surface of the double injection molded portion 23 is more concave downward than the upper surface of the bottom surface 21, so that the upper surface of the double injection molded portion 23 and the upper surface of the bottom surface 21 are formed to produce a step equal to the protrusion degree of the vulnerable portion 11b of the battery cell 11.

[0114] Figure 8 A vehicle V is shown in which a battery pack including a battery module having an improved housing is installed. It should be understood that the present disclosure may provide a battery module including the above housing, a battery pack P including the battery module, and a vehicle V including the battery pack P. For those skilled in the art, the manufacturing methods of the battery pack P and the vehicle V are known, and thus descriptions thereof will be omitted.

[0115] It should be understood that the described embodiments are illustrative and not restrictive in all aspects, and the scope of the present disclosure will be represented by the following claims rather than the detailed description described. And the meaning and scope of the claims to be described later and all changes and modifications derived from equivalent concepts should be interpreted as included in the scope of the present disclosure.

[0116] Embodiments are described above with reference to a plurality of illustrative embodiments of the present disclosure. However, the embodiments are not limited to the embodiments and drawings set forth herein, and those skilled in the art may obtain many other modifications and embodiments within the technical scope of the present disclosure. In addition, although not explicitly described in the description of the embodiments, the effects and predictable effects based on the configurations in the present disclosure are also included within the scope of the present disclosure.

Claims

1. A housing configured to accommodate a battery cell stack, the housing comprising: a frame configured to accommodate the battery cell stack; a cutout portion formed by cutting off a portion of the frame interfering with an end portion of a vulnerable portion formed to protrude from one side of each battery cell of the battery cell stack in a width direction; and A double injection molded portion is connected to the cut-off portion.

2. The housing according to claim 1, wherein: The frame is made of sheet metal, and The double injection molded part is made of insulating synthetic resin.

3. The housing according to claim 2, wherein: The insulating synthetic resin is also a thermally conductive synthetic resin.

4. The housing according to any one of claims 1 to 3, wherein: The frame is configured to be U-shaped with its upper portion and two side portions in the length direction being open, and The cutout portion is formed at one end portion of the bottom surface of the frame in the length direction, and has a shape that is recessed in the bottom surface with two corners where two side walls of the frame meet the bottom surface as boundaries in the width direction.

5. The housing according to claim 4, wherein: The double injection molded portion is continuous with at least a portion of the machined surface of the cutout portion, replaces the concave bottom surface of the frame, and constitutes a portion of the bottom surface.

6. The housing according to claim 5, wherein: A height of a bottom surface of the double injection molded portion is recessed from a height of the bottom surface of the frame to form a step.

7. The housing according to claim 6, wherein: The double injection molded portion protrudes and extends from the frame in the length direction.

8. The housing according to claim 6, wherein: The thickness of the double injection molded portion in the height direction is equal to the thickness of the bottom surface of the frame in the height direction, and A lower surface of the double injection molded portion is formed to protrude further downward than a lower surface of the frame.

9. The housing according to claim 6, wherein: The thickness of the double injection molded portion in the height direction is smaller than the thickness of the bottom surface of the frame in the height direction, and The lower surface of the double injection molded portion is formed to be continuous with the lower surface of the frame at the same height.

10. The housing according to claim 6, wherein: The two-shot molded portion covers a portion of a bottom surface to an inner side of a boundary surface of the cutout portion.

11. The housing according to any one of claims 1 to 3, wherein: The frame is configured as a U-shape with its upper portion and two side portions in the length direction being open. The cutout portion is formed at one end portion in the length direction of the bottom surface of the frame, and is formed to completely penetrate the bottom surface with two corners where two side walls of the frame meet the bottom surface as boundaries in the width direction, and The double injection molded portion is formed to cover a region penetrating the bottom surface.

12. The housing according to claim 11, wherein: A height of a bottom surface of the double injection molded portion is recessed from a height of the bottom surface of the frame to form a step.

13. The housing according to claim 12, wherein: The double injection molded portion protrudes and extends from the frame in the length direction.

14. The housing according to claim 12, wherein: The thickness of the double injection molded portion in the height direction is equal to the thickness of the bottom surface of the frame in the height direction, and A lower surface of the double injection molded portion is formed to protrude further downward than a lower surface of the frame.

15. The housing according to claim 12, wherein: The thickness of the double injection molded portion in the height direction is smaller than the thickness of the bottom surface of the frame in the height direction, and The lower surface of the double injection molded portion is formed to be continuous with the lower surface of the frame at the same height.

16. The housing according to claim 12, wherein: The two-shot molded portion covers a portion of a bottom surface to an inner side of a boundary surface of the cutout portion.

17. A battery module, comprising: A battery cell stack in which battery cells each having a vulnerable portion are stacked; as well as a housing configured to accommodate the battery cell stack, Wherein, the housing comprises: a frame configured to accommodate the battery cell stack; a cutout portion formed by cutting out a portion of the frame interfering with an end portion of the vulnerable portion formed to protrude from one side of each battery cell of the battery cell stack in a width direction; and A double injection molded portion is connected to the cut-off portion.

18. The battery module according to claim 17, wherein: The cutout portion is formed as a portion that completely penetrates the frame, and The double injection molded portion is formed to cover a region penetrating a portion of the frame.

19. The battery module according to claim 17, wherein: An inner surface of the double injection molded portion includes a surface that is more concave than an inner surface of the frame where the cutout portion is provided.

20. The battery module according to claim 17, wherein: The frame includes two side walls, the two side walls are arranged to be spaced apart from each other in the width direction; and a bottom surface connecting lower end portions of the two side walls in the width direction, and The cutout portion is provided at one end portion of the bottom surface in the length direction.

21. The battery module according to claim 20, wherein: The cutout portion provides a portion where one end portion of the bottom surface of the frame in the length direction is more recessed inward than one end portions of the two side walls in the length direction.

22. The battery module according to claim 17, wherein: The two-shot molded portion covers a portion of a bottom surface to an inner side of a boundary surface of the cutout portion.

23. A battery pack comprising the battery module according to any one of claims 17 to 22.

24. A vehicle having the battery pack according to claim 23 installed therein.

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