Wire for electrical connection, and battery module for forming electrical connection using same

Abstract

The present invention relates to a wire for electrical connection, the wire comprising: a metal wire positioned in the center on the inside; a plurality of gas discharge members added to the outer surface of the metal wire and disposed along the longitudinal direction of the metal wire; an insulating tube surrounding the outer surface of the metal wire to which the plurality of gas discharge members are added; and a highly fire-resistant coating layer covering the insulating tube, wherein liquids and gases that are generated inside the wire in the event of a fire can be prevented from being discharged in an unspecified direction.

Description

Wire for electrical connection and battery module forming electrical connection using the wire

[0001] This application claims the benefit of priority to Korean Patent Application No. 2023-0085041, filed June 30, 2023, the entire contents of which are incorporated herein by reference.

[0002] The present invention relates to an electrical connection wire and a battery module that forms an electrical connection using the same. Specifically, the present invention relates to an electrical connection wire that can direct the discharge of liquid and gas generated when the covering of the wire in an electrical connection state is deformed by flame in a specific direction, and a battery module that forms an electrical connection using the same.

[0003]

[0004] Demand is growing for secondary batteries, which can address air pollution caused by fossil fuel use and store electric energy generated from alternative energy sources. For example, lithium secondary batteries, with their high energy density per unit weight, are used not only as a power source for mobile devices like cell phones, tablets, Bluetooth earphones, and e-cigarettes, but also as a power source for medium- to large-sized devices like electric bicycles, electric scooters, and electric vehicles.

[0005] As the types of devices that use lithium secondary batteries as an energy source expand, the application of lithium secondary batteries is also expanding to devices that require high capacity and high output.

[0006] In line with this trend, battery modules in which a number of battery cells are electrically connected and battery packs in which the battery modules are connected in series and / or parallel are manufactured and used.

[0007] Busbars can be used as a means of electrically connecting multiple battery cells. However, if busbars, which are difficult to shape-change, cannot be used, wires can be used.

[0008] Figure 1 is a front view and a partially enlarged view of a conventional general wire.

[0009] Referring to Fig. 1, a wire (100) has a metal conductor (110) made of copper positioned at the innermost side, and an insulating layer (120) surrounds the outer surface of the metal conductor (110), and the insulating layer (120) may be configured as an insulating tube. The outer surface of the insulating layer (120) is surrounded by a heat-resistant layer (130) that is less likely to undergo shape deformation at high temperatures. The heat-resistant layer (130) may be configured in a strip shape and may be added in a form that winds the insulating layer (120).

[0010] A fire may occur when a heat reaction occurs in a battery cell inside a battery module or battery pack and the heat is transferred to the surrounding battery cells. A fire in a battery cell may spread to a fire in the battery module or battery pack.

[0011] At this time, if the temperature of the wires that electrically connect the battery cells or electrically connect the internal structure of the battery module or battery pack increases, the insulating tube may crack as it becomes ceramicized. The gas generated at this time may cause a portion of the heat-resistant layer (130) wound in a strip shape to tear.

[0012] As a result, if the metal conductor (110) in the inner center of the wire (100) is exposed to the outside, it may come into contact with a conductive component in the vicinity, causing a short circuit.

[0013] In addition, since the phenomenon of the heat-resistant layer tearing occurs at an unspecified location, it is difficult to predict the location where the heat-resistant layer will tear during the design process of the battery module or battery pack, making it difficult to prepare for a short circuit in advance.

[0014] Patent Document 1 relates to a special cable for aviation equipment comprising multiple sets of cable core units, wherein the outer side of the cable core units is covered with an outer cover, and a flame-retardant filling layer is installed between the outer cover and the cable core units. An outer shielding layer is installed on the outer side of the outer cover, an insulating flame-retardant layer is installed on the outer side of the outer shielding layer, and a heat-conductive layer and a high-temperature-resistant layer are sequentially formed on the outer side of the insulating flame-retardant layer. A plurality of ventilation holes are installed at equiangular intervals in the heat-conductive layer, and a ventilation assembly is installed so as to be connected to the ventilation holes. Using the ventilation assembly, a low-temperature inert gas can pass through the ventilation holes to cool and insulate the outer high-temperature-resistant layer from the heat-conductive layer, and at the same time, heat can be released from the inner side.

[0015] Patent Document 1 provides a method for cooling and insulating a high-temperature layer by providing a ventilation hole in a heat-conducting layer and installing a ventilation assembly to communicate with the ventilation hole, thereby ensuring the safety of the cable in a high-temperature environment or when a fire occurs.

[0016] Patent Document 2 relates to a fire-retardant cable, comprising a central fire-resistant cable core, the outer surface of which is sequentially wrapped with a fire-retardant layer, a covering layer, and an outer sheath layer. The fire-resistant cable core comprises multiple conductors, a mica-based fire-retardant layer surrounding the conductors, and an insulating film. A plurality of gas passages are installed within the covering layer, and the heat dissipation and cooling functions of the cable are realized through the flow of gas within the gas passages.

[0017] The cable of Patent Document 2 ensures safety by cooling the cable by allowing gas to flow through a gas passage provided in the outermost layer, the outer sheath.

[0018] However, a technology is needed that can prevent the metal conductor inside from being exposed when the insulating layer and heat-resistant layer added to the outer surface of the wire are cracked, and at the same time, prevent the metal conductor from coming into contact with surrounding components even if it is exposed.

[0019]

[0020] (Prior art literature)

[0021] (Patent Document 1) Chinese Patent Publication No. 115312244 (November 8, 2022)

[0022] (Patent Document 2) Chinese Utility Model Registration No. 210296002, April 10, 2020)

[0023]

[0024] The present invention is intended to solve the above-mentioned problem, and provides a battery connection wire that can prevent the wire outer covering from being peeled off at an unspecified location by inducing gas generated inside the wire to be discharged to both ends of the wire when a fire occurs, and a battery module that forms an electrical connection using the same.

[0025]

[0026] To achieve this purpose, an electrical connection wire according to the present invention may include a metal conductor positioned at an inner center, a plurality of gas discharge members added to an outer surface of the metal conductor and arranged along the length direction of the metal conductor, an insulating tube wrapping the outer surface of the metal conductor to which the plurality of gas discharge members are added, and a highly refractory coating layer covering the insulating tube.

[0027] The above plurality of gas discharge members may be configured in a ring shape that is fitted to the outer surface of the metal conductor.

[0028] The above plurality of gas discharge members may have grooves formed parallel to the length direction of the metal conductor for discharging gas and liquid.

[0029] The grooves for the flow path formed in each of the plurality of gas discharge members may be arranged so that their longitudinal positions are aligned with those of grooves for the flow path formed in adjacent gas discharge members.

[0030] Liquid and gas generated when the insulating tube is deformed by flame and temperature can move to both longitudinal ends of the metal conductor through the groove for the flow path.

[0031] An insulating layer may further be included that wraps around the outer surface of the metal conductor, and the plurality of gas discharge members may be added to the outer surface of the insulating layer.

[0032] The plurality of gas discharge members may have a groove for discharging gas and liquid formed parallel to the longitudinal direction of the metal conductor, and a plurality of through holes may be formed in the groove for the flow path of the plurality of gas discharge members, and the through holes may be formed in a direction perpendicular to the bottom of the groove for the flow path.

[0033] Liquid and gas generated when the insulating layer is deformed by flame and temperature move through the through hole to the groove for the flow path, and the liquid and gas can move to both longitudinal ends of the metal conductor through the groove for the flow path.

[0034] The above gas discharge member may be composed of an insulating and heat-resistant material.

[0035] The plurality of gas discharge members may be arranged to be spaced apart at regular intervals, and an empty space may be formed between adjacent plurality of gas discharge members.

[0036] A first terminal and a second terminal can be connected to each of the two ends of the above metal conductor.

[0037] The present invention provides a battery module that forms an electrical connection using the above-mentioned electrical connection wire.

[0038] The present invention can also be provided in a form in which various means for solving the above problem are combined.

[0039]

[0040] In the past, when the insulating layer constituting the wire was made of ceramic, liquid and gas were discharged through the cracks in the insulating layer. However, the present invention has a plurality of gas discharge members in which gas flow path grooves are formed on the outer surface of the metal conductor, thereby enabling the liquid and gas to be discharged toward both ends of the wire.

[0041] In addition, since an insulating gas discharge member is added to the outer surface of the metal conductor even if the insulating tube is lost, the metal conductor does not directly contact the components around the wire, so a short circuit caused by contact between the wire and the components around the wire can be prevented.

[0042]

[0043] Figure 1 is a front view and a partially enlarged view of a conventional general wire.

[0044] Figure 2 is a perspective view of a wire according to the first embodiment.

[0045] Fig. 3 is an enlarged perspective view of a portion of the wire of Fig. 2 with a gas discharge member added to the outer surface of the metal conductor.

[0046] Figure 4 is a cross-sectional view of the wire of Figure 2.

[0047] Fig. 5 is an enlarged perspective view of a state in which a gas discharge member is added to the insulating layer on the outer surface of a metal conductor among some wires according to the second embodiment.

[0048] Fig. 6 is a cross-sectional view of a wire according to the second embodiment.

[0049]

[0050] Hereinafter, with reference to the attached drawings, embodiments of the present invention will be described in detail, so that those skilled in the art can easily implement the present invention. When describing the operating principles of the embodiments of the present invention in detail, detailed descriptions of known functions or components will be omitted if they are deemed to unnecessarily obscure the gist of the present invention.

[0051] Parts with similar functions and actions are designated by the same drawing reference numerals throughout the drawings. Throughout the specification, when a part is said to be connected to another part, this includes not only direct connections but also indirect connections with other elements intervening. Furthermore, inclusion of a component does not exclude other components unless otherwise specifically stated, but rather implies the inclusion of additional components.

[0052] The description that concretizes or adds to the components may be applied to all inventions unless there is a special limitation, and is not limited to the description of a specific invention.

[0053] Throughout the description and claims of the invention herein, the singular includes the plural unless otherwise stated.

[0054] Throughout the description and claims of the present invention, the term "or" includes "and" unless otherwise stated. Therefore, "comprising A or B" means all three cases of including A, including B, or including A and B.

[0055] The present invention is described in detail with examples according to the drawings.

[0056] Fig. 2 is a perspective view of a wire according to the first embodiment, Fig. 3 is an enlarged perspective view of a part of the wire of Fig. 2 in which a gas discharge member is added to the outer surface of a metal conductor, and Fig. 4 is a cross-sectional view of the wire of Fig. 2.

[0057] Referring to FIGS. 2 to 4, a wire (200) according to the first embodiment includes a metal conductor (210) positioned at the inner center, a plurality of gas discharge members (220) added to the outer surface of the metal conductor (210) and arranged along the longitudinal direction (L) of the metal conductor (210), and an outer layer (230) wrapping the outer surface of the metal conductor (210) to which the plurality of gas discharge members (220) are added.

[0058] The outer layer (230) includes an insulating tube (231) that wraps the outer surface of the metal conductor (210) and a high-refractory covering layer (232) that covers the insulating tube (231).

[0059] The metal conductor (210) must have high electrical conductivity and may be composed of a material selected from the group consisting of copper, nickel, aluminum, and alloys containing these, for example.

[0060] A plurality of gas discharge members (220) are arranged at a predetermined interval from each other on the outer surface of the metal conductor (210). In order to ensure a constant degree of freedom in shape deformation at all positions of the wire, the intervals between the plurality of gas discharge members (220) may be configured to be constant. Alternatively, the intervals between the plurality of gas discharge members may be formed irregularly, taking into account the characteristics of the portion where the wires are joined.

[0061] The gas discharge member (220) is configured in the shape of a ring with a through hole formed in the center and a metal wire inserted into the through hole to pass through.

[0062] The insulating tube (231) may be composed of a material such as polyethylene or silicone. The high-refractory covering layer (232) may be added in the form of a strip-shaped tape wound along the outer surface of the insulating tube (231), and may be composed of, for example, at least one selected from the group consisting of a mica tape and a glass tape. Specifically, the mica tape may be added in the form of spirally winding around the outer surface of the insulating tube, and then the glass tape may be spirally wound around the outer surface of the mica tape.

[0063] The gas discharge member (220) has a groove (221) for discharging gas and liquid formed parallel to the longitudinal direction (L) of the metal conductor (210).

[0064] In the event that a fire occurs in the electronic components to which the wire (200) is connected due to abnormal operation of the electronic components, the insulating tube constituting the wire (200) may be deformed by the flame and high temperature to become ceramic or melt and deform, and at this time, liquid and gas are generated. The wire (200) according to the present invention has a gas discharge member (220) having a flow path groove (221) formed inside the insulating tube (231), so that the liquid and gas generated inside the wire (200) can move through the flow path groove (221).

[0065] The grooves (221) for the euro are arranged at predetermined intervals along the length direction (L) of the metal conductor (210) throughout the wire (200), so that liquid and gas can be discharged to both ends of the wire (200) through the grooves for the euro (221).

[0066] At this time, in order to discharge liquid and gas quickly and safely through the flow path groove (221) formed in each of the plurality of gas discharge members (220), the flow path groove (221) formed in each of the plurality of gas discharge members (220) may be arranged so that the longitudinal (L) position matches the flow path groove (221) formed in the adjacent gas discharge member (220).

[0067] The gas discharge member (220) may be composed of an insulating and heat-resistant material, for example, an inorganic material including silicon, carbon, and ceramic, or a high-heat-resistant polymer resin.

[0068] Specifically, the high heat-resistant polymer resin is at least one selected from the group consisting of phenol resin, epoxy resin, polyimide, polyphenylene sulfide, polysulfone, polyethersulfone, polyetherimide, polyarylate, and polyetheretherketone.

[0069] Meanwhile, the gas discharge members (220) are arranged to be spaced apart at regular intervals, and an empty space is formed between the adjacent plurality of gas discharge members (220). Considering that the gas discharge members (220) may be configured to have low flexibility due to the material properties thereof, by arranging the gas discharge members (220) to be spaced apart, the wire (200) can be bent in the portion where the gas discharge members (220) are absent, thereby providing a wire (200) that is free to change shape.

[0070] Fig. 5 is an enlarged perspective view of a part of a wire according to the second embodiment in which a gas discharge member is added to the insulating layer on the outer surface of the metal conductor, and Fig. 6 is a cross-sectional view of the wire according to the second embodiment.

[0071] Referring to FIGS. 5 and 6, the wire according to the second embodiment differs from the wire according to the first embodiment in that it further includes an insulating layer (240) that wraps around the outer surface of the metal conductor (210). In the wire according to the second embodiment, the insulating layer (240) is further added to the entire outer surface of the metal conductor (210), and a plurality of gas discharge members (220) are added to the outer surface of the insulating layer (240).

[0072] The wire according to the second embodiment can further prevent the exposure of the metal conductor (210) by including an insulating layer (240), thereby ensuring higher insulation of the wire.

[0073] The insulating layer (240) may be composed of the same material as the insulating tube (231), or may be composed of a polymer resin having high insulating properties that is different from the insulating tube (231). For example, the insulating layer (240) may be composed of a polymer resin such as polyethylene, polyvinyl chloride, natural rubber, polyester, epoxy resin, melamine resin, phenol resin, and polyurethane, resin, mica, asbestos, ceramic, or glass fiber.

[0074] In the wire according to the second embodiment, a plurality of gas discharge members (220) are formed with grooves (221) for discharging gas and liquid in a direction parallel to the longitudinal direction of the metal conductor (210). One through hole (222) or two or more through holes (222) are formed in each of the grooves (221) for the flow path of the plurality of gas discharge members (220), and the through holes (222) are formed in a direction perpendicular to the bottom of the grooves (221) for the flow path or in a direction orthogonal to the surface of the insulating layer (240).

[0075] When a fire occurs in electrical components where wires are electrically connected or when the wires are exposed to a high-temperature environment, the liquid and gas generated when the insulating layer (240) is melted and deformed by the flame and temperature pass through the through hole (222) and move to the flow path groove (221), and the liquid and gas can move to both longitudinal ends of the metal conductor (210) through the flow path groove (221).

[0076] The wire according to the second embodiment has a through hole (222) in the groove (221) for the flow path of the gas discharge member (220), thereby not only inducing discharge of liquid and gas generated by deformation of the insulating tube located on the outside of the gas discharge member (220), but also inducing liquid and gas generated by deformation of the insulating layer (240) located on the inside of the gas discharge member (220) to move toward both ends of the wire.

[0077] Therefore, the metal conductor can be prevented from being exposed by the sheath layer cracking due to gas being released from an unspecified portion of the wire. Furthermore, by constructing the gas discharge member with an insulating and refractory material of a certain thickness, even if the insulating or outer layer is damaged and the metal conductor is exposed, the metal conductor can be prevented from coming into contact with conductive electrical components.

[0078] The wire according to the present invention can be used to form an electrical connection between a plurality of battery cells, and a first terminal and a second terminal are connected to each of the two ends of the metal conductor (210), so that the wire can be electrically connected to the first battery cell and the second battery cell, respectively.

[0079] The shape of the first terminal and the second terminal is not particularly limited, such as a shape with a hole formed to enable screw fastening, a ring terminal shape, a shape having a welding part, a clamp shape, etc.

[0080] Additionally, the first terminal and the second terminal can be combined with electrical components constituting the battery module and / or battery pack to form an electrical connection.

[0081] Since known technologies can be applied to the present invention regarding the configuration, structure, and materials of the above battery module and battery pack, a description thereof is omitted in this specification.

[0082] The present invention includes a battery module and a battery pack that form an electrical connection using the above wire.

[0083]

[0084] Anyone with ordinary knowledge in the field to which the present invention pertains will be able to perform various applications and modifications within the scope of the present invention based on the above contents.

[0085]

[0086] (Explanation of symbols)

[0087] 100, 200: Wire

[0088] 110, 210: Metal conductor

[0089] 120, 240: Insulation layer

[0090] 130: Heat-resistant layer

[0091] 220: Gas exhaust system

[0092] 221: Home for Euro

[0093] 222: Through hole

[0094] 230: Outer layer

[0095] 231: Insulating tube

[0096] 232: High-refractory coating layer

[0097] 240: Insulation layer

[0098] L: length direction

Claims

1. Metal wire located in the inner center; A plurality of gas discharge members added to the outer surface of the metal conductor and arranged along the length of the metal conductor; An insulating tube that wraps around the outer surface of the metal conductor to which the plurality of gas discharge members are added; and A highly refractory coating layer covering the above insulating tube; Wire for electrical connection including:

2. In paragraph 1, The above plurality of gas discharge members are electrical connection wires configured in a ring shape that is fitted to the outer surface of the metal conductor.

3. In paragraph 1, The above plurality of gas discharge members are electrical connection wires in which grooves for discharging gas and liquid are formed parallel to the longitudinal direction of the metal conductor.

4. In paragraph 3, An electrical connection wire in which liquid and gas generated when the insulating tube is deformed by flame and temperature move to both longitudinal ends of the metal conductor through the groove for the euro.

5. In paragraph 1, Further comprising an insulating layer covering the outer surface of the above metal conductor, An electrical connection wire in which a plurality of gas discharge members are added to the outer surface of the insulating layer.

6. In paragraph 5, The above plurality of gas discharge members have grooves for discharging gas and liquid formed parallel to the longitudinal direction of the metal conductor, A plurality of through holes are formed in the grooves for the above plurality of gas discharge members, The above through hole is an electrical connection wire formed in a direction perpendicular to the bottom of the groove for the euro.

7. In paragraph 6, Liquid and gas generated when the above insulating layer is deformed by flame and temperature move to the groove for the flow path through the through hole, The above liquid and gas are electrical connection wires that move to both longitudinal ends of the metal conductor through the grooves for the euro.

8. In paragraph 1, The above gas discharge member is an electrical connection wire made of an insulating and heat-resistant material.

9. In paragraph 1, The above plurality of gas discharge members are arranged to be spaced apart at regular intervals, An electrical connection wire comprising an empty space between adjacent gas discharge members.

10. In paragraph 1, An electrical connection wire having a first terminal and a second terminal connected to each of the two ends of the above metal conductor.

11. A battery module forming an electrical connection using an electrical connection wire according to any one of claims 1 to 10.

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