Battery module insulation structure

Abstract

The present invention provides a battery module structure including an electrode assembly, a frame that is open at the top and houses the electrode assembly, a top plate that covers the top of the frame, a first insulating film attached to an inner surface of the frame including an inner surface of a side wall, and a second insulating film attached to the inner surface of the top plate.

Description

[Technical Field]

[0001] This application claims the benefit of priority based on Korean Patent Application No. 10-2022-0175923 dated December 15, 2022, and all contents disclosed in the documents of that Korean patent application are incorporated herein by reference.

[0002] The present invention relates to a battery module including a battery cell stack and a housing that houses the battery cell stack, the battery module having an insulating structure that insulates the battery cell stack and the housing from each other. [Background technology]

[0003] Secondary batteries, which are easily applicable to a wide range of products and have electrical properties such as high energy density, are commonly used not only in portable devices but also in electric vehicles or hybrid vehicles powered by electrical sources, power storage devices, etc. These secondary batteries are attracting attention as a new energy source because they not only have the primary advantage of dramatically reducing the use of fossil fuels, but also because they are environmentally friendly and improve energy efficiency by not producing any by-products from energy use.

[0004] While small mobile devices use one or two or three battery cells per device, medium to large devices such as automobiles require high output and large capacity, so medium to large battery modules, which electrically connect multiple battery cells, are used.

[0005] Since it is preferable that medium- to large-sized battery modules be manufactured with small size and weight if possible, prismatic batteries, pouch-shaped batteries, etc., which can be stacked with high density and have low weight relative to capacity, are mainly used as battery cells for medium- to large-sized battery modules.

[0006] 1 and 2 are exploded and perspective views, respectively, showing the structure of a battery module. Referring to these drawings, a typical battery module may include a battery cell stack 1 formed by stacking a plurality of pouch-shaped battery cells, a frame 2 that is open at the top and houses the battery cell stack 1, and a top plate 3 that covers the top of the frame 2. The frame 2 and the top plate 3 may be made of an electrically conductive material such as metal, and may be assembled by joining them together using a method such as welding.

[0007] On the other hand, if the frame 2 and the top plate 3 are made of an electrically conductive material such as metal, there is a risk that the frame 2 or the top plate 3 may short-circuit with the battery cell stack 1. Such a short-circuit may cause thermal runaway in the battery cell stack 1, resulting in a risk of fire, and even if thermal runaway does not occur, it may result in the battery module not performing at all or not performing sufficiently. For this reason, it is preferable that the frame 2 and the top plate 3 are insulated from the battery cell stack 1.

[0008] 3 is a cross-sectional view of a battery module. Referring to FIG. 3, a first insulating film 21 and a second insulating film 31 may be attached to the inner surfaces of the frame 2 and the top plate 3, respectively, to insulate them from the battery cell stack 1. The first insulating film 21 and the second insulating film 31 may be attached to the inner surfaces of the frame 2 and the top plate 3, respectively, to be spaced a predetermined distance from the boundary 4 where the frame 2 and the top plate 3 are joined together. This is to prevent poor joining due to interference between the first insulating film 21 and the second insulating film 31 during the joining process of the frame 2 and the top plate 3 at the boundary 4, or to prevent damage to the first insulating film 21 and the second insulating film 31 due to heat generated during the welding process.

[0009] 4 is a partially enlarged view of the boundary of the battery module in FIG. 3. Referring to this, the frame 2 and the top plate 3 are exposed to the battery cell stack 1 at the boundary 4, which can cause a short circuit between the battery cell stack 1 and the boundary 4. This short circuit can occur when the battery cell stack 1 comes into contact with the boundary 4 due to flow, or when the battery cell stack 1 has an insulation distance from the boundary 4 that is too short. In this case, the insulation distance can be defined as the length of the shortest path taken by a current flowing between two objects that are separated from each other. Summary of the Invention [Problem to be solved by the invention]

[0010] The present invention was devised against the background of the prior art described above, and its object is to provide a battery module structure that ensures insulation performance between the frame and top plate and the battery cell stack.

[0011] Specifically, the present invention aims to provide a battery module structure that eliminates or reduces the risk of contact between the frame and top plate and the battery cell stack, and increases the insulation distance between the frame and top plate and the battery cell stack.

[0012] A further technical object of the present invention is to provide a battery module structure including an insulating film that does not interfere with the bonding between the frame and the top plate and is not damaged by said bonding.

[0013] The technical object of the present invention is not limited to the above-mentioned objects, and other unmentioned objects and advantages of the present invention can be understood from the following description and can be more clearly understood from the examples of the present invention. Furthermore, it can be easily understood that the objects and advantages of the present invention can be achieved by the means and combinations thereof set forth in the claims. [Means for solving the problem]

[0014] In order to solve the above problems, the present invention provides a battery module structure including an electrode assembly, a frame that is open at the top and houses the electrode assembly, a top plate that covers the top of the frame, a first insulating film attached to an inner surface of the frame including an inner surface of a side wall, and a second insulating film attached to the inner surface of the top plate.

[0015] The battery module according to the present invention includes a structure for ensuring the insulating performance of the first insulating film and the second insulating film. In this specification, the term "insulating performance" refers to the ability to prevent short circuits caused by current flow between the frame and the top plate and the battery cell stack, and can be evaluated based on the ability to block contact, ensure an insulating distance, and prevent damage to the insulator. The insulating distance can be defined as the length of the shortest path taken by current flowing between two objects spaced apart from each other.

[0016] When a boundary is defined as a region where the inner surface of the frame and the inner surface of the top plate contact each other, the battery module may include a first overhang portion formed by folding the first insulating film inward from a first bent portion spaced a predetermined distance in a height direction from the boundary. By spaced a predetermined distance from the boundary, the possibility of the first insulating film interfering with the joining between the frame and the top plate can be reduced or eliminated, and the first insulating film can be prevented from being damaged by welding heat when the frame and the top plate are welded to each other. The predetermined distance can be determined taking into consideration the joining method between the frame and the top plate, and, if the joining method is welding, the welding heat, etc.

[0017] The first insulating film may include a third bent portion formed at an end of the first overhang portion. The first insulating film may be bent inward at both the first bent portion and the third bent portion. Alternatively, the first insulating film may be bent inward at the first bent portion and bent outward at the third bent portion. The bending direction of the first insulating film at the third bent portion may be selected to be suitable for increasing the insulation distance by complicating the current path between the frame / top plate and the battery cell stack.

[0018] The battery module may include a second overhang portion formed by folding the second insulating film inward from a second bend portion spaced a predetermined distance from the boundary portion in a width direction. By spaced a predetermined distance from the boundary portion, the second insulating film can reduce or eliminate the possibility of interference between the frame and the top plate and can prevent the second insulating film from being damaged by welding heat when the frame and the top plate are welded to each other. The predetermined distance can be determined taking into consideration the joining method between the frame and the top plate and, if the joining method is welding, the welding heat.

[0019] The second insulating film may include a fourth bent portion formed at an end of the second overhang portion. The second insulating film may be bent inward at both the second bent portion and the fourth bent portion. Alternatively, the second insulating film may be bent inward at the second bent portion and bent outward at the fourth bent portion. The bending direction of the second insulating film at the fourth bent portion may be selected to be a direction suitable for increasing the insulation distance by complicating the current path between the frame and the top plate and the battery cell stack.

[0020] The first insulating film and the second insulating film may be provided to have a portion overlapping each other in a predetermined direction. In this case, the first insulating film and the second insulating film overlapping each other in a predetermined direction at a certain portion means that when an imaginary line is drawn along a predetermined direction at a point on a certain portion of the first insulating film or the second insulating film, the imaginary line passes through both the first insulating film and the second insulating film.

[0021] In this case, the first insulating film and the second insulating film may include portions that overlap each other in the height direction. Alternatively, the first insulating film and the second insulating film may include portions that overlap each other in the width direction. Alternatively, the first insulating film and the second insulating film may include portions that overlap each other in the thickness direction. By overlapping the first insulating film and the second insulating film, the battery cell stack may be prevented from contacting the frame and the top plate.

[0022] The top plate may include a guide portion extending along the boundary portion and protruding downward, and the guide portion may be formed integrally with the top plate.

[0023] The guide portion may include a tapered portion that guides the tip of the first overhang portion inward in the width direction as the top plate and the frame approach each other in the vertical direction. The first overhang portion may be brought into oblique contact with the tapered portion as the frame and the top plate approach each other in the vertical direction, and may be guided to be further bent inward. This further reduces the risk of the first insulating film interfering with the bonding between the frame and the top plate.

[0024] The second insulating film may include a portion that covers at least a portion of the inner surface of the guide portion. In particular, the second insulating film may include a portion that covers at least a portion of the tapered portion. The covering may be achieved by adhesion. That is, the second insulating film may include a portion that adheres to at least a portion of the tapered portion. In this case, preferably, the second insulating film may be provided by completely adhering to the tapered portion without including the second overhang portion. This may make it easier for the tapered portion to come into oblique contact with the first insulating film.

[0025] When the second insulating film is arranged to cover a portion of the guide portion and the first insulating film is bent inward and guided along the guide portion, the first insulating film and the second insulating film overlap each other, thereby blocking contact between the frame and the top plate and the battery cell stack.

[0026] The first insulating film and the second insulating film may be folded or overlapped with each other as described above, thereby increasing the insulation distance between the frame and the top plate and the battery cell stack.

[0027] When the length of the shortest path taken by a current flowing between the surface of the battery cell stack and the inner surface of the frame is defined as a first insulation distance, the first insulation distance may be greater than the shortest distance between the surface of the battery cell stack and the inner surface of the frame. That is, by providing the first insulation film and the second insulation film, the insulation distance between the frame and the battery cell stack can be increased.

[0028] In this case, the first insulation distance may be 1.5 times or more the shortest distance between the surface of the battery cell stack and the inner surface of the frame. For example, if the width component of the length of the first overhang portion is 1.5 times or more the shortest distance between the surface of the battery cell stack and the inner surface of the frame, the first insulation distance will be 2 times or more the shortest distance between the surface of the battery cell stack and the inner surface of the frame.

[0029] Alternatively, the first insulation distance may be at least twice the shortest distance between the surface of the battery cell stack and the inner surface of the frame. For example, if the width component of the length of the first overhang portion is at least twice the shortest distance between the surface of the battery cell stack and the inner surface of the frame, the first insulation distance will be at least twice the shortest distance between the surface of the battery cell stack and the inner surface of the frame.

[0030] When the length of the shortest path taken by a current flowing between the surface of the battery cell stack and the inner surface of the top plate is defined as a second insulation distance, the second insulation distance may be greater than the shortest distance between the surface of the battery cell stack and the inner surface of the top plate. That is, by providing the second insulating film and the second insulating film, the insulation distance between the top plate and the battery cell stack can be increased.

[0031] In this case, the second insulation distance may be 1.5 times or more the shortest distance between the surface of the battery cell stack and the inner surface of the top plate. For example, if the height component of the length of the second overhang portion is 1.5 times or more the shortest distance between the surface of the battery cell stack and the inner surface of the top plate, the second insulation distance will be 1.5 times or more the shortest distance between the surface of the battery cell stack and the inner surface of the top plate.

[0032] Alternatively, the second insulation distance may be at least twice the shortest distance between the surface of the battery cell stack and the inner surface of the top plate. For example, if the height component of the length of the second overhang portion is at least twice the shortest distance between the surface of the battery cell stack and the inner surface of the top plate, the second insulation distance will be at least twice the shortest distance between the surface of the battery cell stack and the inner surface of the top plate.

[0033] The present invention also provides a battery pack incorporating the battery module and a vehicle structure incorporating the battery pack.

[0034] Because the battery modules have high voltage and / or high capacity, a plurality of them can be housed in a single pack frame to form a battery pack. The plurality of battery modules can be connected in parallel or series to each other by pack bus bars included in the battery pack, resulting in a high overall voltage and capacity. The battery pack can be housed in an electric vehicle powered by a secondary battery. The battery pack can provide power to the vehicle via a motor housed in the vehicle. Detailed structures of these battery packs and vehicles are well known to those skilled in the art, and will not be described in detail herein. [Effects of the Invention]

[0035] The present invention can provide a battery module structure that increases the insulation distance between the frame and top plate and the battery cell stack.

[0036] The present invention can provide a battery module structure that prevents direct contact between the frame and top plate and the battery cell stack.

[0037] The present invention provides a battery module structure that has an overhang portion where the insulating film is folded inward, so that the insulating film does not interfere with or be damaged by the joint between the frame and the top plate, and has improved insulating performance.

[0038] The present invention can provide a battery module structure in which the first insulating film and the second insulating film are guided so that they can be effectively overlapped with each other without interfering with the joint during the process of assembling the frame and the top plate.

[0039] In addition to the above, the present invention can achieve various other effects, which will be explained in each embodiment, or explanations of effects that can be easily inferred by ordinary engineers will be omitted. [Brief explanation of the drawings]

[0040] [Figure 1] FIG. 2 is an exploded perspective view showing the structure of a battery module. [Figure 2] FIG. 2 is a perspective view showing the structure of a battery module. [Figure 3] FIG. 2 is a cross-sectional view of a battery module. [Figure 4] 4 is a partially enlarged view of a boundary portion of the battery module in FIG. 3. FIG. [Figure 5] 1 is a cross-sectional view of a battery module according to a first embodiment of the present invention. [Figure 6] 6 is a partially enlarged view of a boundary portion of the battery module in FIG. 5. FIG. [Figure 7] FIG. 4 is a cross-sectional view of a battery module according to a second embodiment of the present invention. [Figure 8] 8 is a partially enlarged view of a boundary portion of the battery module in FIG. 7. FIG. [Figure 9] FIG. 10 is a cross-sectional view showing a state before the top plate and the frame of a battery module according to a third embodiment of the present invention are assembled together. [Figure 10]FIG. 10 is a cross-sectional view showing the top plate and frame of the battery module according to the third embodiment of the present invention after they have been assembled together. [Figure 11] 10 is a partially enlarged view of a boundary portion of the battery module in FIG. 9. FIG. [Figure 12] 11 is a partially enlarged view of a boundary portion of the battery module in FIG. 10. FIG. [Figure 13] 1 is a diagram showing a battery pack incorporating a battery module according to the present invention; [Figure 14] FIG. 14 is a diagram showing a car incorporating the battery pack of FIG. 13. DETAILED DESCRIPTION OF THE INVENTION

[0041] The above-mentioned objects, features, and advantages will be described in detail below with reference to the accompanying drawings, so that those skilled in the art can easily implement the technical concept of the present invention. In describing the present invention, if a detailed description of known technologies related to the present invention is deemed to obscure the gist of the present invention, the detailed description will be omitted. Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. The same reference numerals in the drawings are used to indicate the same or similar components.

[0042] Although terms such as "first" and "second" are used to indicate various components, it is understood that these components are not limited by these terms. These terms are used merely to distinguish one component from another, and unless otherwise specified, a first component may also be a second component.

[0043] Throughout the specification, unless otherwise specified, each element may be singular or plural.

[0044] Hereinafter, when an arbitrary structure is arranged "on top (or bottom)" of a component or "above (or below)" a component, it means that the arbitrary structure is not only arranged in contact with the upper surface (or lower surface) of the component, but also that other structures may be interposed between the component and the arbitrary structure arranged above (or below) the component.

[0045] Furthermore, when a component is described as being "coupled," "coupled," or "connected" to another component, it should be understood that the components may be directly coupled or connected to each other, but that other components may be "intervening" between the components, or that each component may be "coupled," "coupled," or "connected" via other components.

[0046] As used herein, singular expressions include plural expressions unless the context clearly indicates otherwise. Terms such as "comprise" or "include" in this application should not be interpreted as including all of the multiple components or multiple steps described in the specification, but should be interpreted as meaning that some of the components or some of the steps may not be included, or that additional components or steps may be included.

[0047] In the entire specification, "A and / or B" means A, B or A and B unless otherwise specified, and "C to D" means C or more and D or less unless otherwise specified.

[0048] The present invention provides a battery module structure including: an electrode assembly formed by stacking a plurality of pouch-type battery cells; a frame that is open at the top and houses the electrode assembly; a top plate that covers the top of the frame; a first insulating film attached to an inner surface of the frame, including the inner surface of a side wall; and a second insulating film attached to the inner surface of the top plate.

[0049] The battery module according to the present invention includes a structure for ensuring the insulating performance of the first insulating film and the second insulating film. In this specification, the term "insulating performance" refers to the ability to prevent short circuits caused by current flow between the frame and the top plate and the battery cell stack, and can be evaluated based on the ability to block contact, ensure an insulating distance, and prevent damage to the insulator. The insulating distance can be defined as the length of the shortest path taken by current flowing between two objects spaced apart from each other.

[0050] Preferred embodiments of the present invention will now be described with reference to the accompanying drawings.

[0051] [Example 1] 1 and 2 are exploded and perspective views, respectively, showing the structure of a battery module. Referring to these drawings, the battery module may include a battery cell stack 1, a frame 2, and a top plate 3.

[0052] The battery cell stack 1 may be formed by stacking pouch-type battery cells, but the battery cell stack 1 is not limited to this and may be an assembly of various electrodes or battery cells, despite the name.

[0053] The battery cell stack 1 may be housed in the frame 2. The frame 2 may be formed in a shape that is open at the top. The frame 2 may be made of an electrically conductive material. The frame may be made of a metal material.

[0054] The top of the frame 2 may be covered by the top plate 3. The top plate 3 may be made of an electrically conductive material or a metal material.

[0055] The frame 2 and the top plate 3 may be joined together. Hereinafter, the portion where the frame 2 and the top plate 3 are joined together will be referred to as a boundary portion. Hereinafter, the boundary portion refers to an inner boundary formed between the frame 2 and the top plate 3 when the frame 2 and the top plate 3 are joined together, and may refer to a portion on the frame 2 corresponding to the boundary portion, or a position on the top plate 3 corresponding to the boundary portion.

[0056] In this embodiment, the frame 2 and the top plate 3 may be made of metal and may be joined by welding. Step portions may be provided on the inner side of the upper ends of both side walls of the frame 2, recessed to engage with the top plate 3. In this case, the boundary portion refers to the innermost end of the step portion and a corresponding portion on the top plate 3.

[0057] FIG. 5 is a cross-sectional view of a battery module according to a first embodiment of the present invention, and FIG. 6 is a partially enlarged view of a boundary portion of the battery module of FIG. 5. Referring to these drawings, the battery module may include one or more insulating films that insulate the frame 2 and the top plate 3 from the battery cell stack 1. The insulating films may be made of an insulating material or coated with an insulating material. The insulating films may have a predetermined elasticity.

[0058] The first insulating film 21 may be attached to the inner surface of the frame 2. Specifically, the first insulating film 21 may be attached to the inner surface of the frame 2, including the inner surfaces of both side walls of the frame 2. The first insulating film 21 may have a first bent portion 211, which is spaced a predetermined distance in the height direction from the boundary portion 4, as the boundary of its attachment portion. The first insulating film 21 may be bent inward at the first bent portion 211 to form a first overhang portion 212. The first overhang portion 212 may extend from the first bent portion 211 without being attached to the inner surface of the frame 2. The predetermined distance may be determined in consideration of the joining method between the frame and the top plate, and, if the joining method is welding, the welding heat, etc.

[0059] The second insulating film 31 may be attached to the inner surface of the top plate 3. Specifically, the second insulating film 31 may be attached to the inner surface of the top plate 3, including the inner surfaces of both side walls of the top plate 3. The second insulating film 31 may have a second bent portion 311, which is spaced a predetermined distance from the boundary portion 4 in the width direction, as the boundary of its attachment portion. The second insulating film 31 may be folded inward at the second bent portion 311 to form a second overhang portion 312. The second overhang portion 312 may extend from the second bent portion 311 without being attached to the inner surface of the top plate 3. The predetermined distance may be determined in consideration of the joining method between the frame and the top plate, and, if the joining method is welding, the welding heat, etc.

[0060] The battery module according to this embodiment may include the first insulating film 21 and the second insulating film 31. The first insulating film 21 may be attached to the inner surfaces of both side walls of the frame 2 and may be folded inward from the first folding portion 211 spaced a predetermined distance in the height direction from the border portion 4 to form the first overhang portion 212. The second insulating film 31 may be attached to the inner surface of the top plate 3 and may be folded inward from the second folding portion 311 spaced a predetermined distance in the width direction from the border portion 4 to form the second overhang portion 312.

[0061] According to this embodiment, the first insulating film 21 and the second insulating film 31 are attached at a predetermined distance from the boundary portion 4, and therefore do not interfere with the joining of the frame 2 and the top plate 3. As a result, the frame 2 and the top plate 3 can have sufficient joining strength as designed. In addition, as described above, the first insulating film 21 and the second insulating film 31 are attached at a distance from the boundary portion 4, and therefore, the first insulating film 21 and the second insulating film 31 can be prevented from being damaged by welding heat generated when the frame 2 and the top plate 3 are welded together.

[0062] Furthermore, according to this embodiment, the first overhang portion 212 and the second overhang portion 312 extend inward and are positioned on the shortest path from the battery cell stack 1 to the frame 2 and the top plate 3, which complicates the path along which current flows from the battery cell stack 1 to the frame 2 and the top plate 3, potentially increasing the insulation distance.

[0063] The first insulating film 21 and the second insulating film 31 may be provided to have a portion overlapping each other in a predetermined direction. In this case, the first insulating film 21 and the second insulating film 31 overlapping each other in a predetermined direction at a certain portion means that when an imaginary line is drawn in a predetermined direction at a point on a certain portion of the first insulating film 21 or the second insulating film 31, the imaginary line passes through both the first insulating film 21 and the second insulating film 31.

[0064] In this case, the first insulating film 21 and the second insulating film 31 may include portions that overlap each other in the height direction, or the first insulating film 21 and the second insulating film 31 may include portions that overlap each other in the width direction, or the first insulating film 21 and the second insulating film 31 may include portions that overlap each other in the thickness direction.

[0065] According to this embodiment, the first insulating film 21 and the second insulating film 31 may include overlapping portions in the height, width, and thickness directions. In this case, the overlapping portions may be portions of the first overhang portion 212 and the second overhang portion 312. That is, when imaginary straight lines are drawn in the height, width, and thickness directions at a point on the first overhang portion 212, each imaginary straight line may pass through a point on the second overhang portion 312.

[0066] According to this embodiment, the first insulating film 21 and the second insulating film 31 overlap each other, which may interrupt contact between the battery cell stack 1 and the frame 2 and the top plate 3, complicating the path through which current flows from the battery cell stack 1 to the frame 2 and the top plate 3, and increasing the insulation distance.

[0067] As described above, the first insulating film 21 and the second insulating film 31 can be folded or overlapped with each other as described above, thereby increasing the insulation distance between the frame 2 and the top plate 3 and the battery cell stack 1.

[0068] When the length of the shortest path taken by the current flowing between the surface of the battery cell stack 1 and the inner surface of the frame 2 is defined as a first insulation distance, the first insulation distance may be greater than the shortest distance between the surface of the battery cell stack 1 and the inner surface of the frame 2. In other words, by providing the first insulation film 21 and the second insulation film 31, the insulation distance between the frame 2 and the battery cell stack 1 can be increased.

[0069] In this case, the first insulation distance may be 1.5 times or more the shortest distance between the surface of the battery cell stack 1 and the inner surface of the frame 2. For example, if the width component of the length of the first overhang portion 212 is 1.5 times or more the shortest distance between the surface of the battery cell stack 1 and the inner surface of the frame 2, the first insulation distance will be 2 times or more the shortest distance between the surface of the battery cell stack 1 and the inner surface of the frame 2.

[0070] Alternatively, in this case, the first insulation distance may be at least twice the shortest distance between the surface of the battery cell stack 1 and the inner surface of the frame 2. For example, if the width component of the length of the first overhang portion 212 is at least twice the shortest distance between the surface of the battery cell stack 1 and the inner surface of the frame 2, the first insulation distance will be at least twice the shortest distance between the surface of the battery cell stack 1 and the inner surface of the frame 2.

[0071] When the length of the shortest path taken by the current flowing between the surface of the battery cell stack 1 and the inner surface of the top plate 3 is defined as a second insulation distance, the second insulation distance may be longer than the shortest distance between the surface of the battery cell stack 1 and the inner surface of the top plate 3. In other words, by providing the second insulating film 31, the insulation distance between the top plate 3 and the battery cell stack 1 can be increased.

[0072] In this case, the second insulation distance may be 1.5 times or more the shortest distance between the surface of the battery cell stack 1 and the inner surface of the top plate 3. For example, if the height component of the length of the second overhang portion 312 is 1.5 times or more the shortest distance between the surface of the battery cell stack 1 and the inner surface of the top plate 3, the second insulation distance will be 1.5 times or more the shortest distance between the surface of the battery cell stack 1 and the inner surface of the top plate 3.

[0073] Alternatively, in this case, the second insulation distance may be at least twice the shortest distance between the surface of the battery cell stack 1 and the inner surface of the top plate 3. For example, if the height component of the length of the second overhang portion 312 is at least twice the shortest distance between the surface of the battery cell stack 1 and the inner surface of the top plate 3, the second insulation distance will be at least twice the shortest distance between the surface of the battery cell stack 1 and the inner surface of the top plate 3.

[0074] According to this embodiment, the first overhang portion 212 and the second overhang portion 312 may form an angle of 45 degrees with the frame 2 and the top plate 3, respectively. In this case, the first overhang portion 212 and the second overhang portion 312 may have a length that is 1.5 to 2 times or more the shortest distance between the battery cell stack 1 and the frame 2 and the shortest distance between the battery cell stack 1 and the top plate 3, respectively.

[0075] According to this embodiment, the width direction component of the first overhang portion 212 and the height direction component of the second overhang portion 312 may be 1.5 times or more the shortest distance between the battery cell stack 1 and the frame 2 and the shortest distance between the battery cell stack 1 and the top plate 3, respectively. In this case, the first insulation distance and the second insulation distance may be 1.5 times or more the shortest distance between the battery cell stack 1 and the frame 2 and the shortest distance between the battery cell stack 1 and the top plate 3, respectively.

[0076] [Example 2] In the following, the explanation of the present embodiment regarding the parts that are not specifically explained is the same as that of the first embodiment.

[0077] Fig. 7 is a cross-sectional view of a battery module according to a second embodiment of the present invention, and Fig. 8 is a partially enlarged view of a boundary portion of the battery module of Fig. 7. Referring to these drawings, the first insulating film 21 and / or the second insulating film 31 may include a third folded portion 213 and / or a fourth folded portion 313 formed by folding back an end portion of the first overhang portion 212 and / or the second overhang portion 312.

[0078] The first insulating film 21 may include a third bent portion 213 formed at the tip of the first overhang portion 212 .

[0079] The first insulating film 21 may be bent in the same direction or in different directions at the first bending portion 211 and the third bending portion 213. That is, the first insulating film 21 may be bent inward at both the first bending portion 211 and the third bending portion 213, or the first insulating film 21 may be bent inward at the first bending portion 211 and bent outward at the third bending portion 213. The bending direction of the first insulating film 21 at the third bending portion 213 may be selected to be a direction suitable for increasing the insulation distance by complicating the current path between the frame 2 and the top plate 3 and the battery cell stack 1.

[0080] The second insulating film 31 may include a fourth bent portion 313 formed at the tip of the second overhang portion 312 .

[0081] The second insulating film 31 may be bent in the same direction or in different directions at the second bending portion 311 and the fourth bending portion 313. That is, the second insulating film 31 may be bent inward at both the second bending portion 311 and the fourth bending portion 313, or the second insulating film 31 may be bent inward at the second bending portion 311 and bent outward at the fourth bending portion 313. The bending direction of the second insulating film 31 at the fourth bending portion 313 may be selected to be a direction suitable for increasing the insulation distance by complicating the current path between the frame 2 and the top plate 3 and the battery cell stack 1.

[0082] According to this embodiment, the first insulating film 21 and the second insulating film 31 may include the third bending portion 213 and the fourth bending portion 313, respectively. In this case, the first insulating film 21 may be bent in different directions at the first bending portion 211 and the third bending portion 213, and the second insulating film 31 may be bent in the same direction at the second bending portion 311 and the fourth bending portion 313. Accordingly, the tip of the first overhang portion 212 and the tip of the second overhang portion 312 may be bent in directions facing each other, and the first overhang portion 212 and the second overhang portion 312 may be interdigitated with each other.

[0083] According to this embodiment, the first overhang portion 212 and the second overhang portion 312 are interlocked or overlap each other, which can more reliably prevent contact between the battery cell stack 1 and the frame 2 and the top plate 3, and can also further increase the insulation distance.

[0084] [Example 3] In the following, the explanation of the parts of this embodiment that are not specifically explained are the same as those of the first and second embodiments.

[0085] 9 and 10 are cross-sectional views showing the top plate and frame of a battery module according to a third embodiment of the present invention before and after assembly, respectively, and FIGS. 11 and 12 are partial enlarged views of the boundary portion of the battery module shown in FIGS. 9 and 10, respectively. Referring to these drawings, the top plate 3 may include a guide portion 32. The guide portion 32 may extend from the top plate 3 along the boundary portion 4 and protrude downward. The guide portion 32 may be formed integrally with the top plate 3.

[0086] The guide portion 32 may include a tapered portion 321. The tapered portion 321 may be formed in a slanted shape so as to extend downward from the inner surface of the guide portion and then be recessed outward. The tapered portion 321 may be in oblique contact with the first overhang portion 212 as the frame 2 and the top plate 3 approach each other in the vertical direction, thereby guiding the tip end of the first overhang portion 212 inward in the width direction.

[0087] The second insulating film 31 may include a portion that covers at least a portion of the inner surface of the guide portion 32. In particular, the second insulating film 31 may include a portion that covers at least a portion of the tapered portion 321. The covering may be achieved by adhesion. That is, the second insulating film 31 may include a portion that adheres to at least a portion of the tapered portion 321. In this case, preferably, the second insulating film 31 may be provided by completely adhering to the tapered portion 321 without including the second overhang portion 312. This may make it easier for the tapered portion 321 to come into oblique contact with the first insulating film 21.

[0088] In the battery module according to this embodiment, the top plate 3 may include the guide portion 32 extending along the boundary portion 4 and protruding downward. The guide portion 32 may be formed integrally with the top plate 3. The guide portion 32 may include the tapered portion 321 formed obliquely on an inner surface thereof. The second insulating film 31 may be attached to and extend to a portion of the tapered portion 321.

[0089] According to this embodiment, the first overhang portion 212 contacts the tapered portion 321 at an angle and is guided inward in the width direction, and the second insulating film 31 is attached up to the tapered portion 321. Therefore, the first insulating film 21 and the second insulating film 31 overlap each other in the thickness direction, completely blocking contact between the battery cell stack 1 and the frame 2 and the top plate 3, and significantly increasing the insulation distance.

[0090] Furthermore, according to this embodiment, the guide portion 32 guides the first overhang portion 212 inward in the width direction, thereby further reducing the risk of the first insulating film 21 interfering with the bonding between the frame 2 and the top plate 3. The second insulating film 31 is attached to the tapered portion 321 and therefore cannot reach the outside of the guide portion 32 where the boundary portion 4 is located, and therefore does not interfere with the bonding between the frame 2 and the top plate 3. This of course also significantly reduces the risk of the first insulating film 21 and the second insulating film 31 being damaged by the welding heat between the frame 2 and the top plate 3.

[0091] The present invention also provides a battery pack incorporating the battery module and a vehicle structure incorporating the battery pack.

[0092] FIG. 13 shows a battery pack incorporating a battery module according to the present invention, and FIG. 14 shows a vehicle incorporating the battery pack of FIG. 13. Referring to these drawings, a plurality of the battery modules (M) can be incorporated into a single pack frame to form a battery pack (P) due to their high voltage and / or high capacity. The plurality of battery modules (M) can be connected in parallel or series to each other by pack bus bars included in the battery pack (P), resulting in a high overall voltage and capacity. The battery pack (P) can be incorporated into an electric vehicle (V) powered by a secondary battery. The battery pack (P) can provide power to the vehicle (V) through a motor incorporated in the vehicle (V). The detailed structures of these battery packs and vehicles are well known to those skilled in the art, and will not be described in detail herein.

[0093] It should be understood that the above-described embodiments are illustrative in all respects and are not limiting, and the scope of the present invention is defined by the following claims rather than the above detailed description. All modifications and variations within the meaning and scope of the following claims, as well as equivalent concepts, should be construed as being included within the scope of the present invention.

[0094] Although the present invention has been described above with reference to illustrative drawings, the present invention is not limited to the embodiments and drawings disclosed in this specification, and various modifications may be made by those skilled in the art within the scope of the technical concept of the present invention. Furthermore, even if the effects of the configuration of the present invention are not explicitly described in the above description of the embodiments of the present invention, it is natural that the effects that can be predicted by the configuration should also be recognized. [Explanation of symbols]

[0095] 1 Battery cell stack 2 frames 21 First insulating film 211 1st bend 212 First Overhang 213 3rd bend 3 Top Plate 31 Second insulating film 311 2nd bending section 312 Second Overhang 313 4th bend 32 Guide section 321 Tapered section 4 Boundary M Battery Module P Battery pack V Automobile X length direction Y width direction Z height direction

Claims

1. a battery cell stack; a frame that is open at the top and that houses the battery cell stack; a top plate covering the upper part of the frame; a first insulating film attached to an inner surface of the frame, including the inner surface of the side wall; and a second insulating film attached to the inner surface of the top plate; When the area where the inner surface of the frame and the inner surface of the top plate contact each other is defined as a boundary portion, a first overhang portion formed by bending the first insulating film inward from a first bent portion spaced a predetermined distance from the boundary portion in a height direction; the second insulating film includes at least one second overhang portion formed by bending inward from a second bent portion spaced a predetermined distance from the boundary portion in the width direction, Battery module.

2. a third bent portion formed at a tip end of the first overhang portion; The battery module according to claim 1 .

3. The first bent portion and the third bent portion of the first insulating film are bent in different directions. The battery module according to claim 2 .

4. The first and third bent portions of the first insulating film are bent in the same direction. The battery module according to claim 2 .

5. a fourth bent portion formed at a tip end of the second overhang portion; The battery module according to any one of claims 1 to 4.

6. The second bent portion and the fourth bent portion of the second insulating film are bent in different directions. The battery module according to claim 5 .

7. The bending directions of the second bent portion and the fourth bent portion of the second insulating film are the same. The battery module according to claim 5 .

8. The first insulating film and the second insulating film include portions that overlap each other in a height direction. The battery module according to claim 1 .

9. the first insulating film and the second insulating film include portions that overlap each other in the width direction; The battery module according to claim 1 .

10. the first insulating film and the second insulating film include portions that overlap each other in a thickness direction; The battery module according to claim 1 .

11. the top plate includes a guide portion extending along the boundary portion and protruding downward; the guide portion includes a tapered portion that guides a tip end of the first overhang portion inward in the width direction as the top plate and the frame approach each other in the vertical direction. The battery module according to claim 1 .

12. the second insulating film includes a portion that covers at least a portion of the inner surface of the guide portion; The battery module according to claim 11 .

13. the second insulating film includes a portion that covers at least a part of the tapered portion; The battery module according to claim 11 .

14. the second insulating film includes a portion that is attached to at least a part of the tapered portion; The battery module according to claim 13.

15. When the length of the shortest path taken by a current flowing between the surface of the battery cell stack and the inner surface of the frame is defined as a first insulation distance, the first insulation distance is greater than the shortest distance between the surface of the battery cell stack and the inner surface of the frame; The battery module according to claim 1 .

16. the first insulation distance is 1.5 times or more the shortest distance between the surface of the battery cell stack and the inner surface of the frame; The battery module according to claim 15.

17. the first insulation distance is at least twice the shortest distance between the surface of the battery cell stack and the inner surface of the frame; The battery module according to claim 16.

18. When the length of the shortest path taken by a current flowing between the surface of the battery cell stack and the inner surface of the top plate is defined as a second insulation distance, the second insulation distance is greater than the shortest distance between the surface of the battery cell stack and the inner surface of the top plate; The battery module according to claim 1 .

19. the second insulation distance is 1.5 times or more the shortest distance between the surface of the battery cell stack and the inner surface of the top plate; The battery module according to claim 18.

20. the second insulation distance is at least twice the shortest distance between the surface of the battery cell stack and the inner surface of the top plate; The battery module of claim 19.

21. A battery module comprising the battery module of claim 1. Battery pack.

22. 22. A battery pack comprising: car.

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