Battery case, and battery pack and vehicle comprising same

Abstract

A battery case according to the present invention comprises: a pack frame that forms an accommodation space for a plurality of battery cells; a case lead for covering the accommodation space; a gasket interposed between the pack frame and the case lead; and a bracket for covering at least a portion of edge of the case lead, wherein the bracket has a plurality of coupling parts coupled to the case lead by means of a fastening member, adjacent coupling parts of the plurality of coupling parts being spaced a predetermined distance apart from each other.

Description

Battery case and battery pack including same, automobile

[0001] The present invention relates to a battery case, a battery pack including the same, and an automobile.

[0002] As demand for portable electronic products such as laptops, video cameras, and mobile phones rapidly increases and the commercialization of robots and electric vehicles becomes more widespread, research into high-performance secondary batteries capable of repeated charging and discharging is actively underway.

[0003] Currently commercialized secondary batteries include nickel-cadmium batteries, nickel-hydrogen batteries, nickel-zinc batteries, and lithium secondary batteries. Among these, lithium secondary batteries are in the spotlight for their advantages of being free to charge and discharge, having a very low self-discharge rate, and high energy density, as they have almost no memory effect, which is a phenomenon in which the chargeable capacity of a battery decreases when charging without completely discharging the battery, compared to nickel-based secondary batteries.

[0004] These lithium secondary batteries primarily use lithium oxide and carbon materials as the positive and negative electrode active materials, respectively. Lithium secondary batteries comprise an electrode assembly comprising positive and negative plates coated with the positive and negative electrode active materials, respectively, with a separator interposed between them, and an outer case, i.e., a battery case, that seals and encloses the electrode assembly together with an electrolyte.

[0005] In general, lithium secondary batteries can be classified into can-type secondary batteries in which the electrode assembly is built into a metal can and pouch-type secondary batteries in which the electrode assembly is built into a pouch of an aluminum laminate sheet, depending on the shape of the outer packaging material.

[0006] Recently, secondary batteries are widely used for driving or energy storage not only in small devices such as portable electronic devices but also in medium and large devices such as electric vehicles and energy storage systems (ESS).

[0007] These secondary batteries can be housed together inside a module case while being electrically connected in large numbers to form a single battery module, and these battery modules are then electrically connected again in a narrow space to form a battery pack to increase energy density.

[0008] Battery packs with high energy densities can be vulnerable to accidents such as fire or explosion if the battery case's structural stability is poor. Therefore, the development of a battery case with high structural stability is urgently needed.

[0009] The present invention was created in consideration of the above-described problems, and has as its primary purpose the provision of a battery case with improved structural stability.

[0010] A battery pack according to one embodiment of the present invention comprises: a pack frame configured to form a space for accommodating a plurality of battery cells; a case lid configured to cover the space; a gasket interposed between the pack frame and the case lid; and a bracket covering at least a portion of an edge of the case lid, wherein the bracket has a plurality of connecting portions that are connected to the case lid by a fastening member, and the plurality of connecting portions can be spaced apart from each other by a predetermined distance.

[0011] The bracket may have a bead portion configured such that at least a portion of the portion facing the case lead protrudes toward the case lead and contacts the case lead.

[0012] The bead portion can be formed at a corresponding portion between adjacent joining portions.

[0013] The battery case may further include a plate-shaped reinforcing member interposed between the case lid and the gasket corresponding to the area between the spaced joints.

[0014] The bracket may include a first portion covering an upper portion of the case lid and a second portion covering a boundary between the case lid and the gasket.

[0015] The second part can cover the boundary of the gasket and pack frame.

[0016] The pack frame may have an extension that extends from a portion forming the receiving space and connects to the case lid.

[0017] The gasket may have a protrusion protruding from at least one of the case lid and the pack frame.

[0018] A battery pack according to one embodiment of the present invention may include a battery case according to the present invention.

[0019] A vehicle according to one embodiment of the present invention may include a battery pack according to the present invention.

[0020] According to one aspect of the present invention, the structural stability of a battery case can be improved. By including a bracket with multiple connecting portions, the bonding stability of the case lid, gasket, and pack frame can be improved. Furthermore, by the bracket additionally covering the area where the case lid, gasket, and pack frame are connected, the bonding strength can be prevented from being reduced due to damage to the connecting portion caused by external physical factors.

[0021] According to another aspect of the present invention, the bonding force between the case lid and the bracket can be maintained approximately constant over the entire area. Since the bracket and the case lid are directly bonded by fastening members only at a plurality of joints, the bonding force may be relatively lower in areas other than the joints compared to the joints. However, by providing a bead portion, the bracket can ensure airtightness between the case lid and the gasket through the fastening members at the plurality of joints, and can ensure airtightness between the case lid and the gasket through the bead portion in areas between the plurality of joints. Therefore, when the internal pressure of the battery case increases, gas is prevented from leaking between the case lid and the gasket in areas corresponding to the plurality of joints at a pressure lower than the designed venting pressure, and the gas can be discharged to a desired location through a venting device or the like.

[0022] According to another aspect of the present invention, when the pack frame and the case lid are coupled, the fastening member can be coupled from outside the receiving space without affecting the receiving space or the battery module received in the receiving space.

[0023] FIG. 1 is a perspective view of a combined battery case according to one embodiment of the present invention.

[0024] Figure 2 is an exploded perspective view of a battery case according to one embodiment of the present invention.

[0025] FIG. 3 is a drawing showing a bracket included in a battery case according to one embodiment of the present invention.

[0026] FIG. 4 is a drawing showing the coupling relationship between a bracket and a fastening member according to one embodiment of the present invention.

[0027] FIG. 5 is a drawing showing a coupling relationship of a battery case according to one embodiment of the present invention.

[0028] FIG. 6 is a drawing showing a bracket included in a battery case according to another embodiment of the present invention.

[0029] FIG. 7 is a drawing showing the coupling relationship between a bracket and a fastening member according to another embodiment of the present invention.

[0030] FIG. 8 is a drawing showing a coupling relationship of a battery case according to another embodiment of the present invention.

[0031] FIG. 9 is a drawing showing a bracket and reinforcing member included in a battery case according to another embodiment of the present invention.

[0032] FIG. 10 is a drawing showing a coupling relationship of a battery case according to another embodiment of the present invention.

[0033] FIG. 11 is a drawing showing a pack frame included in a battery case according to one embodiment of the present invention.

[0034] FIG. 12 is a drawing showing a gasket included in a battery case according to another embodiment of the present invention.

[0035] FIG. 13 is a drawing showing a coupling relationship of a battery case according to another embodiment of the present invention.

[0036] FIG. 14 is a drawing showing a vehicle according to one embodiment of the present invention.

[0037] Before going into the detailed description of the present invention, it should be noted that the terms and words used in this specification and claims should not be interpreted as limited to their usual or dictionary meanings, but should be interpreted with meanings and concepts that conform to the technical idea of ​​the present invention based on the principle that the inventor can appropriately define the concept of the term in order to explain his own invention in the best way. Therefore, the embodiments described in this specification and the configurations illustrated in the drawings are only the most preferred embodiments of the present invention and do not represent all of the technical idea of ​​the present invention. Therefore, it should be understood that there may be various equivalents and modified examples that can replace them at the time of this application.

[0038] The same reference numbers or symbols used in each drawing attached to this specification represent parts or components that perform substantially the same functions. For convenience of explanation and understanding, the same reference numbers or symbols may be used in different embodiments. In other words, even if components with the same reference numbers are depicted in multiple drawings, they do not necessarily represent a single embodiment.

[0039] In the following description, singular expressions include plural expressions unless the context clearly indicates otherwise. Terms such as "comprises" or "comprises" should be understood to indicate the presence of a feature, number, step, operation, component, part, or combination thereof described in the specification, but do not preclude the presence or addition of one or more other features, numbers, steps, operations, components, parts, or combinations thereof.

[0040] In addition, in the description below, expressions such as top, upper, lower, lower, side, front, and rear are expressed based on the direction shown in the drawing, and it is noted in advance that they may be expressed differently if the direction of the object in question changes.

[0041] Additionally, terms including ordinal numbers, such as "first," "second," etc., may be used in this specification and claims to distinguish between components. These ordinal numbers are used to distinguish identical or similar components from each other, and the use of these ordinal numbers should not be interpreted in a limited manner. For example, components associated with these ordinals should not be interpreted in a restricted manner, such as in the order of use or arrangement, based on their numbers. If necessary, each ordinal number may be used interchangeably.

[0042] Hereinafter, embodiments of the present invention will be described with reference to the attached drawings. However, the spirit of the present invention is not limited to the presented embodiments. For example, those skilled in the art who understand the spirit of the present invention may propose other embodiments within the spirit of the present invention by adding, modifying, or deleting components, etc., but such embodiments will also be considered to be within the spirit of the present invention. The shapes and sizes of elements in the drawings may be exaggerated for clarity.

[0043] FIG. 1 is a perspective view showing the assembly of a battery case (10) according to one embodiment of the present invention. FIG. 2 is an exploded perspective view showing the assembly of a battery case (10) according to one embodiment of the present invention. FIG. 3 is a view showing a bracket (500) included in a battery case (10) according to one embodiment of the present invention. FIG. 4 is a view showing a joint relationship between a bracket (500) and a fastening member (B) according to one embodiment of the present invention. FIG. 5 is a view showing a joint relationship of a battery case (10) according to one embodiment of the present invention.

[0044] Referring to FIGS. 1 to 5, the battery case (10) may include a pack frame (200), a case lid (300), a gasket (400), and a bracket (500).

[0045] The pack frame (200) may be configured to form a space for accommodating a plurality of battery cells (S). The space may accommodate a battery module (100) including a plurality of battery cells (S). For example, when the pack frame (200) accommodates a plurality of battery modules (100), the pack frame (200) may be provided with a frame body (210) and a partition wall (220). The frame body (210) may be configured in a box shape with an open top to accommodate a plurality of battery modules (100) therein. The partition wall (220) may partition the internal space of the frame body (210). The partition wall (220) may be provided in a space corresponding to a space between adjacent battery modules (100). Meanwhile, the pack frame (200) is not limited to the structure illustrated and described herein, and for example, the frame body (210) may be configured with a bottom plate, an end plate, a front plate, a side plate, etc.

[0046] The case lid (300) may be configured to cover the receiving space. The case lid (300) may be configured in the form of a cover that covers the upper opening of the pack frame (200) body.

[0047] A gasket (400) may be interposed between the pack frame (200) and the case lid (300). The gasket (400) may seal the space between the pack frame (200) and the case lid (300). The gasket (400) may be interposed along the perimeter of the pack frame (200) and the case lid (300).

[0048] The bracket (500) may cover at least a portion of the edge of the case lid (300). The bracket (500) may have a plurality of connecting portions (A) that are connected to the case lid (300) by a connecting member (B). The connecting member (B) may be a screw.

[0049] A plurality of connecting portions (A) may be spaced apart from each other by a predetermined distance. The bracket (500) may be pressed by the fastening member (B) to bring the case lid (300) and the gasket (400) into close contact. The connecting portion (A) may be an area that is directly pressed by the fastening member (B) when the fastening member (B) is joined to the bracket (500). For example, when the fastening member (B) is a screw, the connecting portion (A) may be an area that comes into contact with the bottom surface of the head of the screw.

[0050] The bracket (500) may include a first portion (510) and a second portion (520). The first portion (510) may cover the upper portion of the case lid (300). The first portion (510) may be provided with a plurality of coupling portions (A). The first portion (510) may be coupled to the case lid (300) by a fastening member (B). The second portion (520) may cover the boundary between the case lid (300) and the gasket (400). The second portion (520) may cover the boundary between the gasket (400) and the pack frame (200). The second portion (520) may cover the boundary between the case lid (300) and the gasket (400) and the boundary between the gasket (400) and the pack frame (200) from the side of the battery case (10). The second portion (520) can be formed by extending from the first portion (510) and bending at an angle of approximately 90 degrees.

[0051] According to this configuration of the present invention, the structural stability of the battery case (10) can be improved. By including a bracket (500) having a plurality of connecting portions (A), the connecting stability of the case lid (300), the gasket (400), and the pack frame (200) can be improved. In addition, since the bracket (500) once again covers the portion where the case lid (300), the gasket (400), and the pack frame (200) are connected, the connecting portion can be prevented from being damaged by external physical factors, thereby reducing the connecting strength.

[0052] Fig. 6 is a drawing showing a bracket (503) included in a battery case (10) according to another embodiment of the present invention. Fig. 7 is a drawing showing a coupling relationship between a bracket (503) and a fastening member (B) according to another embodiment of the present invention. Fig. 8 is a drawing showing a coupling relationship of a battery case (10) according to another embodiment of the present invention.

[0053] Referring to FIGS. 6 to 8, the bracket (503) may have a bead portion (515). The bracket (503) may include a first portion (513) and a second portion (523).

[0054] The first part (513) and the second part (523) are replaced with the description of the first part (510) and the second part (520) described above.

[0055] The bead portion (515) may have at least a portion facing the case lid (300) protrude toward the case lid (300). The bead portion (515) may be configured to contact the case lid (300). The bead portion (515) may be formed at a corresponding portion between adjacent joint portions (A). The bead portion (515) may be formed by pressing the upper surface of the bracket (503) to conform to the shape of the bead portion (515) and protruding downward.

[0056] The thickness of the bead portion (515) may be configured so that the gasket (400) is pressed to the same or similar degree in the joint portion (A) area and the bead portion (515) area. That is, if the bead portion (515) is configured to be excessively thick, the airtightness of the joint portion (A) area may actually deteriorate, and therefore, an appropriate thickness setting is required.

[0057] The thickness of the bead portion (515) is configured to be smaller than the thickness of the bracket (503), so that deformation of the structure of the bracket (503) can be minimized when the fastening member (B) is joined. This is because if the bead portion (515) is excessively thick, the bracket (503) may bend by the lever principle due to the force applied when the fastening member (B) is joined with the point of contact between the bead portion (515) and the case lid (300) as the point of action.

[0058] The length of the bracket (503) of the bead portion (515) along the longitudinal direction may be smaller than the value obtained by subtracting the diameter of the head of the fastening member (B) from the length between the adjacent connecting portions (A). The length of the bracket (503) of the bead portion (515) along the width direction may be smaller than the diameter of the head of the fastening member (B). Through this structure of the bead portion (515), when the fastening member (B) is connected, the bead portion (515) can be prevented from being damaged by the fastening member (B). If the bead portion (515) is too large, when the fastening member (B) is connected, the fastening member (B) may directly contact the bead portion (515), which may cause a deformation of the shape of the bead portion (515), and the purpose of the present invention of the bead portion (515) reinforcing and applying pressure only in the area excluding the connecting portion (A) may not be achieved.

[0059] According to this configuration of the present invention, the bonding force between the case lid (300) and the bracket (503) can be maintained approximately constant over the entire area. Since the bracket (503) and the case lid (300) are directly bonded by the fastening member (B) only at the plurality of bonding portions (A), the bonding force may be relatively lower in areas other than the bonding portion (A) compared to the bonding portion (A). However, by providing the bead portion (515), the bracket (500) can ensure airtightness between the case lid (300) and the gasket (400) through the fastening member (B) at the plurality of bonding portions (A), and can ensure airtightness between the case lid (300) and the gasket (400) through the bead portion (515) in the area between the plurality of bonding portions (A). Accordingly, when the internal pressure of the battery case (10) increases, gas is prevented from leaking between the case lead (300) and the gasket (400) in the area corresponding to the plurality of joints (A) at a pressure lower than the designed venting pressure, so that the gas can be discharged to a desired location through a venting device or the like.

[0060] FIG. 9 is a drawing showing a bracket (500) and a reinforcing member (600) included in a battery case (10) according to another embodiment of the present invention.

[0061] Referring to FIG. 9, the battery case (10) may further include a reinforcing member (600).

[0062] A reinforcing member (600) may be interposed between the case lid (300) and the gasket (400) corresponding to the area between the adjacent joint portions (A). The reinforcing member (600) may be plate-shaped. The reinforcing member (600) may be a component corresponding to the bead portion (515) described above. That is, the bead portion (515) may not necessarily be formed integrally with the bracket (500).

[0063] FIG. 10 is a drawing showing the coupling relationship of a battery case (10) according to another embodiment of the present invention.

[0064] Referring to FIG. 10, the bead portion (515) does not necessarily have to be provided on the bracket (500). As shown in FIG. 10, the bead portion (315) may be formed on the case lid (300) rather than the bracket (500), and a reinforcing member (600) rather than the bead portion (315) may be interposed between the case lid (300) and the gasket (400).

[0065] FIG. 11 is a drawing showing a pack frame (200) included in a battery case (10) according to one embodiment of the present invention.

[0066] Referring to FIG. 11, the pack frame (200) may have an extension (230).

[0067] Referring to FIGS. 2, 5, and 11 together, the extension portion (230) can be extended from a portion forming the receiving space and coupled with the case lid (300). The extension portion (230) can be provided on a portion covering a side of the battery module (100) of the pack frame (200). By this structure of the pack frame (200), when the pack frame (200) and the case lid (300) are coupled, the fastening member (B) can be coupled from the outside of the receiving space without affecting the receiving space or the battery module (100) accommodated in the receiving space.

[0068] Fig. 12 is a drawing showing a gasket (400) included in a battery case (10) according to another embodiment of the present invention. Fig. 13 is a drawing showing a coupling relationship of a battery case (10) according to another embodiment of the present invention.

[0069] Referring to FIGS. 12 and 13, the gasket (400) may have a protrusion (410).

[0070] The protrusion (410) may protrude from at least one of the case lid (300) and the pack frame (200). The protrusion (410) may be formed to extend along the circumference of the case lid (300) and the pack frame (200). A plurality of protrusions (410) may be provided. The plurality of protrusions (410) may be arranged at equal intervals. By this structure of the protrusion (410), each protrusion (410) may press the circumference of the case lid (300) in a closed curve without interruption or the circumference of the pack frame (200) in a closed curve without interruption, thereby increasing airtightness. Furthermore, by providing a plurality of such protrusions (410), the airtightness may be further increased. In addition, when pressurizing the gasket (400) by combining the fastening member (B), the protrusion (410) can be compressed with sufficient pressure while in contact with the case lid (300) and the pack frame (200) with a small area.

[0071] Referring back to Fig. 13, the bead portion (515) can be formed in a corresponding portion between the adjacent protrusions (410). Through this structure of the bead portion (515), the effect of the case lead (300) and the bracket (500) maintaining a constant bonding force over the entire area of ​​the bracket (500) can be improved.

[0072] Referring back to FIG. 2, the battery pack may include a battery case (10). Although not illustrated in the drawing, the battery pack may further include a battery module (100) including a plurality of battery cells, various other components in addition to the battery case (10), such as components of a battery pack known at the time of filing of the present invention, such as a BMS, a relay, a current sensor, etc.

[0073] Fig. 14 is a drawing showing a vehicle (1) according to one embodiment of the present invention.

[0074] Referring to FIG. 14, the automobile (1) may include a battery pack. In addition to the battery pack, the automobile (1) may further include various other components included in the automobile (1). For example, in addition to the battery pack according to the present invention, the automobile (1) may further include a body, a motor, a control device such as an electronic control unit (ECU), etc.

[0075] While the present invention has been described with reference to the accompanying drawings, focusing on preferred embodiments, it will be apparent to those skilled in the art that numerous obvious modifications can be made without departing from the scope of the present invention. Therefore, the scope of the present invention should be construed as encompassing the many examples of such modifications within the scope of the claims.

[0076] [Explanation of symbols]

[0077] 1 car

[0078] 10 Battery Case

[0079] 100 battery modules

[0080] 200 Pack Frames

[0081] 210 frame body

[0082] 220 bulkhead

[0083] 230 extension

[0084] 300 case leads

[0085] 400 gasket

[0086] 410 protrusion

[0087] 500,503 bracket

[0088] 510, 513 Part 1

[0089] 315, 515 bead

[0090] 520, 523 Part 2

[0091] 600 reinforcing members

[0092] A joint

[0093] B fastening member

[0094] S battery cell

Claims

1. A pack frame configured to form a space for accommodating a plurality of battery cells; A case lid configured to cover the above-mentioned accommodation space; A gasket interposed between the pack frame and the case lid; and A bracket comprising at least a portion of a corner of the case lid, The above brackets are, It has a plurality of connecting parts that are connected to the case lead by a fastening member, A battery case characterized in that the above plurality of connecting parts are spaced apart from each other by a predetermined distance.

2. In paragraph 1 The above brackets are, A battery case characterized in that at least a portion of a portion facing the case lead is provided with a bead portion configured to protrude toward the case lead and come into contact with the case lead.

3. In paragraph 2, The above bead part, A battery case characterized in that it is formed in a corresponding portion between the above mutually adjacent connecting portions.

4. In paragraph 1, The above battery case, A battery case further comprising a plate-shaped reinforcing member interposed between the case lead and the gasket corresponding to the area between the mutually adjacent joints.

5. In paragraph 1 The above brackets are, A battery case characterized by comprising a first part covering the upper portion of the case lid and a second part covering the boundary between the case lid and the gasket.

6. In paragraph 5, The second part above is, A battery case characterized by covering the boundary of the gasket and the pack frame.

7. In paragraph 1, The above pack frame is, A battery case characterized by having an extension portion extending from a portion forming the above-described receiving space and coupled with the case lead.

8. In paragraph 1, The above gasket, A battery case characterized by having a protrusion protruding from at least one of the case lead and the pack frame.

9. A battery pack characterized by including a battery case according to any one of claims 1 to 8.

10. A vehicle comprising a battery pack according to Article 9.

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