Battery pack and cover for a battery pack

Abstract

A battery pack and a cover for a battery pack are provided. A battery pack according to the present invention can include a battery pack case in which an accommodation space portion is divided in which a plurality of battery modules are accommodated, the battery pack case having an open side, and a cover installed to cover the side of the battery pack case and having a graphene coating formed thereon.

Description

Technical Field

[0001] This application claims the benefit of priority based on Korean Patent Application No. 10-2023-0184745, filed on December 18, 2023, the entire contents of which are included as part of this specification.

[0002] The present invention relates to a battery pack and a cover for the battery pack, the cover being capable of: rapidly dispersing heat within the cover during thermal runaway; and preventing localized heat concentration and flame leakage by preventing explosion due to gas pressure. Background Technology

[0003] Typically, a secondary battery consists of a negative electrode, a positive electrode, and an electrolyte, and generates electrical energy through a chemical reaction. Due to its ability to be charged and discharged, the use of secondary batteries is gradually increasing. Because of the high energy density per unit weight of lithium-ion batteries, they are widely used as power sources for electronic communication equipment or as drive sources for high-output hybrid and electric vehicles.

[0004] Regarding the shape of these secondary batteries, there is an increasing demand for prismatic and pouch-shaped batteries, which, due to their thinness, can be used in products such as mobile phones. As for the materials used in secondary batteries, there is a growing demand for lithium-ion batteries and lithium-ion polymer batteries, which offer high energy density, discharge voltage, and output stability.

[0005] Currently, widely used types of rechargeable batteries include lithium-ion batteries, lithium polymer batteries, nickel-cadmium batteries, nickel-metal hydride batteries, and nickel-zinc batteries. The operating voltage of these battery cells is approximately 2.5V to 4.2V. When a higher output voltage is required, multiple battery cells can be connected in series to form a battery module, and multiple battery modules can be connected to form a battery pack. Furthermore, depending on the required charging and discharging capacity of the battery pack, multiple battery cells can be connected in parallel to form a battery pack. Therefore, the number of battery cells and the electrical connection structure of the battery pack can be selected in various ways according to the required output voltage or charging and discharging capacity.

[0006] Electric vehicles may be subjected to unexpected shocks and vibrations to their battery packs during operation. When such shocks and vibrations are applied to the battery pack, the electrical connections between the battery modules may break, or the battery pack housing supporting the battery modules may deform. Therefore, battery packs used in electric vehicles need to have sufficient durability and rigidity to resist external shocks and vibrations.

[0007] Battery packs increase durability and rigidity by installing multiple package beams within the battery casing. These package beams span the interior of the tray that forms the battery pack casing and also serve as structural elements within the tray that divide the space for mounting the battery modules. The tray with package beams provides increased impact resistance and is less prone to deformation from external impacts or vibrations.

[0008] Importantly, battery packs comprising multiple battery modules are prone to releasing heat generated from each module. There are instances where heat generated from the battery modules during the charging and discharging processes of the battery pack is not effectively dissipated. In such cases, the battery modules may deteriorate as heat accumulates within them. When this deterioration accelerates, the battery modules may catch fire or explode. Therefore, cooling and safety devices are installed in high-output, high-capacity battery packs to cool each battery module.

[0009] When thermal runaway occurs in a battery module, gases and flames escape from that module. As the gases and flames rise, the cover is heated. Here, the gases and flames concentrate heat on specific areas of the cover, and as the cover is locally heated, the softening of those areas increases. When gas pressure is applied to the expandable portion, the cover may rupture or break. When the cover ruptures or breaks, flames and gases can be released from the battery pack.

[0010] The background technology of the present invention is disclosed in Korean Patent Application Publication No. 2021-0127508 (publication date: October 22, 2021, entitled "Battery Pack Including Automatic Separation Bus Bar"). Summary of the Invention

[0011] Technical issues

[0012] To address the aforementioned problems, the present invention aims to provide a battery pack and a cover for the battery pack, the cover being provided with a graphene coating capable of rapidly dispersing heat applied to the cover.

[0013] The purpose of this invention is to provide a battery pack and a cover for the battery pack, the cover being able to prevent the cover from softening locally due to heat, thereby preventing the cover from exploding or being damaged.

[0014] The purpose of this invention is to provide a battery pack and a cover for the battery pack, the cover being able to change the shape of the graphene coating without using a separate mold.

[0015] The purpose of this invention is to provide a battery pack and a cover for the battery pack, wherein the central reinforcement and the side reinforcements enhance the rigidity of the cover while serving as a central venting channel.

[0016] The technical problem to be solved by this invention is not limited to the above-described objectives. Other objectives and advantages not described in this invention can be understood through the following description and will be more clearly understood through examples of this invention. Furthermore, it is apparent that the objectives and advantages of this invention can be embodied by the means and combinations thereof indicated in the claims.

[0017] Technical solution

[0018] To address the aforementioned problems, the battery pack according to the present invention may include: a battery pack housing having a receiving space within the battery pack housing for accommodating a plurality of battery modules, and the battery pack housing having an open side; and a cover covering the open side of the battery pack housing and having a graphene coating disposed on the cover.

[0019] The graphene coating can be applied to the inner surface of the cover.

[0020] The graphene coating can be applied to the entire inner surface of the cover.

[0021] The plurality of reinforcing parts may have a curved shape.

[0022] The cover may have a long side and a short side, and the plurality of reinforcing portions may include: a central reinforcing portion disposed at the center of the short side of the cover and formed along the long side of the cover; and a plurality of side reinforcing portions arranged parallel to the short side of the cover and arranged along the long side of the cover.

[0023] The central reinforcement can protrude outward to form a central exhaust channel.

[0024] The plurality of side reinforcements can protrude outward to form a plurality of side exhaust channels connected to the central exhaust channel.

[0025] The cover may include: a cover plate having the central reinforcement, the plurality of side reinforcements and the graphene coating; and a reinforcing frame stacked on the periphery of the cover plate to enhance the rigidity of the cover plate.

[0026] The reinforcing frame may include a plurality of reinforcing panels extending toward the central reinforcing portion.

[0027] The reinforcing panel may be provided with a recessed reinforcing step portion, which is disposed between and in contact with multiple side reinforcing portions.

[0028] The cover for a battery pack according to the present invention comprises: a cover plate having a graphene coating; and a reinforcing frame stacked on the periphery of the cover plate to enhance the rigidity of the cover plate.

[0029] The graphene coating can be applied to the inner surface of the cover plate.

[0030] The graphene coating can be applied to the entire inner surface of the cover plate.

[0031] The cover plate may have a long side and a short side.

[0032] The cover plate may include: a central reinforcement disposed at the center of the short side of the cover plate and formed along the long side of the cover plate; and a plurality of side reinforcements configured to extend parallel to the short side of the cover plate and arranged along the long side of the cover plate.

[0033] The central reinforcement can protrude outward to form a central exhaust channel.

[0034] The plurality of side reinforcements can protrude outward to form a plurality of side exhaust channels connected to the central exhaust channel.

[0035] The reinforcing frame includes a plurality of reinforcing panels extending toward the central reinforcing portion.

[0036] The reinforcing panel may be provided with a recessed reinforcing step portion, which is disposed between and in contact with the plurality of side reinforcing portions.

[0037] Beneficial effects

[0038] According to the present invention, a graphene coating is formed on the cover, and the graphene coating can rapidly disperse the heat applied to the cover. Therefore, the cover can be prevented from being locally heated by flames and gases during thermal runaway of the battery module.

[0039] According to the present invention, since the graphene coating rapidly disperses the heat applied to the lid, it can prevent the lid from being locally softened by heat, thereby preventing the lid from exploding or being damaged.

[0040] According to the present invention, since the graphene coating is formed on the cover, no adhesive is used on the cover, so that the graphene coating will not detach from the cover due to heat.

[0041] According to the present invention, since the graphene coating is applied to the surface of the cap, it is not necessary to use a separate mold to change the shape of the graphene coating.

[0042] According to the present invention, the central reinforcing portion can protrude outward to form a central exhaust channel. Therefore, the central reinforcing portion can serve as a central exhaust channel while simultaneously enhancing the rigidity of the cover.

[0043] According to the present invention, a plurality of side reinforcements protrude outward to form a plurality of side exhaust channels connected to the central exhaust channel. Therefore, the plurality of side reinforcements can serve as side exhaust channels while simultaneously reinforcing the rigidity of the cover.

[0044] According to the present invention, since the reinforcing frame is stacked on the periphery of the cover plate to enhance the rigidity of the cover plate, gas or flame can be prevented from leaking through the edge of the battery pack.

[0045] In addition to the aforementioned beneficial effects, the specific effects of the present invention will be further described while describing the specific details of the invention. Attached Figure Description

[0046] Figure 1 This is a schematic perspective view of a battery pack according to the present invention.

[0047] Figure 2 It is shown schematically. Figure 1 A three-dimensional view of the battery pack casing.

[0048] Figure 3 This is a schematic illustration of a battery module housed within. Figure 2 A 3D view of the battery pack casing.

[0049] Figure 4 It is shown schematically. Figure 1 A 3D view of the battery pack cover.

[0050] Figure 5 It is shown schematically. Figure 1 An exploded perspective view of the battery pack cover.

[0051] Figure 6 It schematically shows the composition. Figure 5 A three-dimensional view of the cover plate.

[0052] Figure 7 It schematically shows the composition. Figure 5 A three-dimensional view of the reinforced frame of the cover.

[0053] Figure 8 It schematically shows the composition. Figure 5 A three-dimensional view of the graphene coating on the cover.

[0054] [Explanation of reference numerals in the attached figures]

[0055] 100: Battery pack

[0056] 102: Battery Module

[0057] 110: Battery pack casing

[0058] 111: Partition

[0059] 112: Capacity

[0060] 113: Connecting groove

[0061] 114: Exhaust port

[0062] 120: Cover

[0063] 121: Cover plate

[0064] 122: Central Reinforcement Department

[0065] 122a: Central exhaust channel

[0066] 123: Side reinforcement

[0067] 123a: Side exhaust passage

[0068] 125: Strengthen the framework

[0069] 126: Enhanced Panel

[0070] 127: Strengthen the steps

[0071] 128: Graphene Coating Detailed Implementation

[0072] Preferred embodiments of the invention will be described below with reference to the accompanying drawings.

[0073] This invention is not limited to the embodiments disclosed below, and various modifications can be applied and these modifications can be implemented in various different forms. The embodiments described herein are provided merely to complete the disclosure of this invention and fully inform those skilled in the art of the scope of the invention. Therefore, this invention is not limited to the embodiments disclosed below, and it should be understood that this invention includes all variations and equivalents contained within the technical spirit and scope of this invention, as well as configurations of one embodiment that are replaced or added to by configurations of another embodiment.

[0074] The accompanying drawings are provided merely to facilitate understanding of the embodiments disclosed herein, and it should be understood that the technical concepts disclosed herein are not limited to the drawings, but rather encompass all variations, equivalents, and substitutions within the spirit and scope of the invention. In the drawings, although components may be exaggerated or diminished in size or thickness for ease of understanding, this should not be construed as limiting the scope of protection of the invention.

[0075] The terminology used herein is for describing particular embodiments or examples only and is not intended to limit the invention. Furthermore, singular expressions include plural expressions unless the context clearly specifies otherwise. Throughout this document, terms such as “comprising” and “consisting of” are intended to indicate the presence of features, numbers, steps, operations, components, parts, or combinations thereof described in the specification. That is, it should be understood that terms such as “comprising” and “consisting of” as used herein do not preclude the possibility of the presence or addition of one or more other features, numbers, steps, operations, components, parts, or combinations thereof.

[0076] While various components may be described using ordinal terms such as "first" and "second," these components are not limited by these terms. These terms are used only for the purpose of distinguishing one component from another.

[0077] It should be understood that when a component is referred to as "connected" to another component, the component can be directly connected to the other component, or there can be an intervening component in between. On the other hand, when a component is referred to as "directly connected" to another component, it should be understood that there is no intervening component in between.

[0078] When an element is referred to as being "above" or "below" another element, it should be understood to include not only situations where the element is directly above or below the other element, but also situations where there are other elements in between.

[0079] Unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. Terms such as those defined in common dictionaries should be interpreted as having a meaning consistent with the context of the relevant field, and unless expressly defined herein, terms such as those defined in common dictionaries should not be interpreted in an ideal or overly formal sense.

[0080] The battery pack according to an embodiment of the present invention will be described below.

[0081] Figure 1 This is a schematic perspective view of a battery pack according to the present invention. Figure 2 It is shown schematically. Figure 1 A 3D view of the battery pack casing. Figure 3 This is a schematic illustration of a battery module housed within. Figure 2 A 3D view of the battery pack casing. Figure 4 It is shown schematically. Figure 1 A 3D view of the battery pack cover, and Figure 5 It is shown schematically. Figure 1 An exploded perspective view of the battery pack cover.

[0082] refer to Figures 1 to 5 According to an embodiment of the present invention, the battery pack 100 includes a battery pack housing 110. The entire battery pack housing 110 may be made of a metallic material.

[0083] The battery module 102 includes multiple battery cells (not shown). These battery cells may include pouch cells, rectangular cells, and cylindrical cells. The battery module 102 is disposed within a corresponding receiving space 112.

[0084] Multiple separators 111 are installed in the battery pack housing 110 to separate receiving spaces 112 in which multiple battery modules 102 are received. The separators 111 can be arranged parallel to the short side of the battery pack housing 110 along its long side. The separators 111 enhance the rigidity of the battery pack housing 110. The separators 111 can prevent the flow of gas and flame into adjacent receiving spaces 112 in the event of thermal runaway or thermal runaway propagation. The battery pack housing 110 has an open side. A battery pack frame is mounted around the outer surface of the battery pack housing 110. Vent holes 114 are formed on the front and rear sides of the battery pack frame.

[0085] The cover 120 can be mounted to cover one open side of the battery pack housing 110. The cover 120 is attached to the outer frame of the battery pack housing 110 to define the internal space of the battery pack housing 110. The attachment can be performed by various methods such as welding or fastening. A graphene coating 128 is disposed on the cover 120. The thermal conductivity of the graphene coating 128 is more than twice that of diamond, thereby improving heat transfer efficiency and durability. Furthermore, because the graphene coating 128 rapidly disperses heat applied to the cover 120, it prevents the cover 120 from being locally heated by flames and gases in the event of thermal runaway of any battery module 102. Therefore, it prevents the cover 120 from being locally softened by heat, thereby preventing the cover 120 from exploding or being damaged. Additionally, it can delay or suppress the venting of gases and flames from the battery pack 100 during thermal runaway of the battery pack 100.

[0086] Traditionally, mica sheets can be attached to the inner surface of the cover 120 using adhesive. In this case, when the battery module 102 experiences thermal runaway and heat propagation, the adhesive can melt as the cover 120 is heated, and the mica sheets may separate. Furthermore, since the mica sheets are approximately 1 mm thick, the space for gas flow can become relatively narrow. Additionally, because reinforcing ribs are formed in the cover 120 to enhance its rigidity, a mold must be used to match the shape of the mica sheets to the shape of the cover 120. Moreover, since the mold must be remanufactured when changing the shape of the cover 120, the manufacturing cost of the battery pack 100 may increase.

[0087] In contrast, since a graphene coating 128 is provided on the cover 120 of the present invention, no adhesive is used on the cover 120, preventing the graphene coating 128 from detaching from the cover 120 due to heat. Furthermore, since the graphene coating 128 is applied to the surface of the cover 120, a separate mold is not required. Moreover, the graphene coating 128 can be applied to covers 120 of various shapes. Furthermore, due to the formation of a very thin graphene coating 128, the space for gas flow in the cover 120 becomes relatively wide, increasing space utilization.

[0088] A graphene coating 128 is disposed on the inner surface of the cover 120. The graphene coating 128 is formed in a stepped manner to correspond to the central reinforcement 122 and side reinforcement 123 of the cover 120, as described below. Here, the graphene coating 128 can be disposed on the entire inner surface of the cover 120. Therefore, the graphene coating 128 can distribute heat throughout the cover 120. Figure 5 In the illustration, the graphene coating 128 is shown as separate from the cap. However, this is for ease of description, and the graphene coating 128 is actually coated on the cap 120.

[0089] The cover 120 can be an integral rectangle with long and short sides. The shape of the cover 120 corresponds to the shape of the battery pack housing 110.

[0090] Figure 4 It is shown schematically. Figure 1 A 3D view of the battery pack cover. Figure 5 It is shown schematically. Figure 1 An exploded perspective view of the battery pack cover. Figure 6 It schematically shows the composition. Figure 5 A three-dimensional view of the cover plate. Figure 7 It schematically shows the composition. Figure 5 A three-dimensional view of the reinforced frame of the cover, and Figure 8 It schematically shows the composition. Figure 5 A three-dimensional view of the graphene coating on the cover.

[0091] refer to Figures 4 to 8 Multiple reinforcing parts 122 and 123 with curved shapes can be provided at the cover 120. The multiple reinforcing parts 122 and 123 are formed in a stepped manner at the cover 120 to increase the structural rigidity of the cover 120.

[0092] The multiple reinforcing portions 122 and 123 may include one or more central reinforcing portions 122 and multiple side reinforcing portions 123. When two rows of battery modules 102 are arranged along the long side in the battery pack 100, a central reinforcing portion 122 may be provided at the center of the short side of the battery pack 100. Furthermore, when three or more rows of battery modules 102 are arranged along the long side in the battery pack 100, two or more central reinforcing portions 122 may be provided at the center of the short side of the battery pack 100.

[0093] The central reinforcement 122 can be disposed parallel to the long side of the cover 120 at the center of the short side of the cover 120. The central reinforcement 122 can be straight. A plurality of side reinforcements 123 can be arranged parallel to the short side of the cover 120 along the long side of the cover 120.

[0094] The central reinforcement 122 protrudes outward to form a central exhaust channel 122a. Here, a communicating groove 113 with the same size as the central reinforcement 122 can be provided at the longitudinal center of the plurality of baffles 111. The degree of protrusion of the central reinforcement 122 and the depth of the communicating groove 113 can be determined with reference to the size of the central exhaust channel 122a.

[0095] Multiple side reinforcements 123 protrude outward to form multiple side exhaust channels 123a connected to the central exhaust channel 122a. The multiple side reinforcements 123 may be straight. At least one side reinforcement 123 may correspond to one side of each receiving space 112. The number of side reinforcements 123 corresponding to a corresponding receiving space 112 can be selected according to the size of the receiving space 112. Since the multiple side exhaust channels 123a are connected to the central exhaust channel 122a, gases and flames generated in the battery module 102 can be discharged from the battery pack 100 through the multiple side exhaust channels 123a, the central exhaust channel 122a, and the exhaust port 114.

[0096] According to an embodiment of the present invention, the graphene coating 128 prevents the cover 120 from softening due to local temperature rise, and the plurality of reinforcements 122 and 123 prevent structural damage to the cover 120, thereby providing a battery pack 100 in which the structural, mechanical and thermal stability of the cover 120 is simultaneously enhanced.

[0097] Furthermore, according to an embodiment of the present invention, since the graphene coating 128 rapidly transfers and dissipates heat while exhausting gas and flame through the exhaust channels 122a and 123a, a battery pack 100 is provided that can prevent thermal runaway, improve cooling and heat dissipation efficiency, and reduce the risk of explosion.

[0098] The cover 120 includes a cover plate 121 and a reinforcing frame 125.

[0099] A central reinforcement 122 and multiple side reinforcements 123 are provided at the cover plate 121, and a graphene coating 128 is also provided. The cover plate 121 is attached to the periphery of the battery pack housing 110 to cover one side of the battery pack housing 110. The attachment can be achieved by various methods such as welding or fastening.

[0100] A reinforcing frame 125 is stacked around the periphery of the cover plate 121 to enhance the rigidity of the cover plate 121. The reinforcing frame 125 can be welded to the cover plate 121 by spot welding, laser welding, or the like. Alternatively, the reinforcing frame 125 can be attached to the cover plate 121 by means such as fasteners. The reinforcing frame 125 can prevent gas or flame from leaking through the edge of the battery pack 100 by enhancing the rigidity of the periphery of the cover 120.

[0101] The reinforcing frame 125 includes a plurality of reinforcing panels 126 extending toward the central reinforcing portion 122. The reinforcing panels 126 extend toward the central reinforcing portion 122 in a trapezoidal shape, a triangular shape, or the like. Because the reinforcing panels 126 are formed in a trapezoidal or triangular shape, the rigidity of the battery pack housing 110 can be reinforced along the long side of the battery pack housing 110, while preventing the cover 120 from deforming along the short side of the battery pack housing 110.

[0102] The reinforcing panel 126 may be provided with recessed reinforcing steps 127, which are disposed between and in contact with the side reinforcing parts 123. The multiple reinforcing steps 127 are formed in a straight line shape parallel to the short side of the cover plate 121. The multiple reinforcing steps 127 can further improve the rigidity of the cover plate 121 along its short side.

[0103] Although the invention has been described with reference to exemplary accompanying drawings, it should be understood that the invention is not limited to the embodiments and drawings disclosed in this specification, and those skilled in the art will understand that various modifications can be made without departing from the scope and spirit of the invention. Furthermore, although the operational effects of the configuration according to the invention are not explicitly described in the description of embodiments of the invention, it should be understood that predictable effects can be recognized through this configuration.

Claims

1. A battery pack, the battery pack comprising: A battery pack housing, wherein a receiving space for accommodating multiple battery modules is partitioned within the battery pack housing, and the battery pack housing has an open side; as well as A cover, the cover covering the one opening side of the battery pack housing and having a graphene coating on the cover, The cover is provided with multiple reinforcing parts that protrude outward to form an exhaust channel.

2. The battery pack according to claim 1, wherein, The graphene coating is disposed on the inner surface of the cover.

3. The battery pack according to claim 2, wherein, The graphene coating is applied to the entire inner surface of the cover.

4. The battery pack according to claim 1, wherein, The plurality of reinforcing parts have a curved shape.

5. The battery pack according to claim 1, wherein, The cover has a long side and a short side, and The plurality of reinforcing parts include: A central reinforcement portion, wherein the central reinforcement portion is disposed at the center of the short side of the cover and formed along the long side of the cover to form a central exhaust channel; and Multiple side reinforcements are provided, which are arranged parallel to the short side of the cover and along the long side of the cover to form multiple side exhaust channels connected to the central exhaust channel.

6. The battery pack according to claim 5, wherein, The cover includes: A cover plate, the cover plate being provided with the central reinforcing portion, the plurality of side reinforcing portions, and the graphene coating; and A reinforcing frame is stacked on the periphery of the cover plate to enhance its rigidity.

7. The battery pack according to claim 6, wherein, The reinforcing frame includes a plurality of reinforcing panels extending toward the central reinforcing portion.

8. The battery pack according to claim 7, wherein, The reinforcing panel is provided with a recessed reinforcing step portion, which is disposed between and in contact with the plurality of side reinforcing portions.

9. A cover for a battery pack, the cover comprising: A cover plate having a graphene coating and multiple reinforcing portions protruding outward to form an exhaust channel; as well as A reinforcing frame is stacked on the periphery of the cover plate to enhance its rigidity.

10. The cover according to claim 9, wherein, The graphene coating is disposed on the inner surface of the cover plate.

11. The cover according to claim 10, wherein, The graphene coating is applied to the entire inner surface of the cover plate.

12. The cover according to claim 9, wherein, The cover plate has a long side and a short side, and The cover plate includes: A central reinforcement portion, wherein the central reinforcement portion is disposed at the center of the short side of the cover plate and formed along the long side of the cover plate to form a central exhaust channel; and Multiple side reinforcements are provided, which are arranged parallel to the short side of the cover plate and along the long side of the cover plate to form multiple side exhaust channels connected to the central exhaust channel.

13. The cover according to claim 12, wherein, The reinforcing frame includes a plurality of reinforcing panels extending toward the central reinforcing portion.

14. The cover according to claim 13, wherein, The reinforcing panel is provided with a recessed reinforcing step portion, which is disposed between and in contact with the plurality of side reinforcing portions.

15. A battery pack comprising a cover according to any one of claims 9 to 14.

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