Wear-resistant and tear-resistant high-temperature-resistant high-voltage cable for vehicle

Abstract

The utility model discloses a kind of wear-resistant tear-resistant high-temperature-resistant high-voltage cable in car, including the conductive wire core of being stranded by several tin-plated copper wires, conductive wire core is coated with heat-resistant high-low temperature cycle anti-cracking crosslinked polyolefin insulation layer, insulation layer is coated with metal shielding layer, metal shielding layer is coated with wear-resistant tear-resistant high-temperature-resistant polyurethane sheath layer, and transition structure for enhancing interface bonding force is equipped between insulation layer and metal shielding layer.The utility model has the beneficial effects that the technical scheme is applicable to the high-voltage distribution system of pure electric vehicle, hybrid electric vehicle, can be used as the connecting cable between power battery and motor controller, charger and battery management system, DC / DC converter and low-voltage storage battery, especially suitable for high-end vehicle with high requirements on electromagnetic compatibility and environmental resistance.

Description

Technical Field

[0001] This utility model relates to the field of cable technology, and in particular to a wear-resistant, tear-resistant, high-temperature resistant high-voltage cable for vehicle interiors. Background Technology

[0002] With the rapid development of the new energy vehicle industry, pure electric vehicles, hybrid electric vehicles, and other models have placed stringent requirements on the performance of high-voltage cables inside the vehicle. As the energy transmission carrier for core components such as power batteries, motor controllers, and chargers, the safety and reliability of high-voltage cables directly affect the overall vehicle operating efficiency and service life.

[0003] In existing technologies, high-voltage cables inside vehicles mostly adopt a three-layer structure of "conductive core + insulation layer + sheath layer". The conductive core is made of tin-plated copper wire stranded together, the insulation layer is made of cross-linked polyolefin material, and the sheath layer is made of polyurethane material, possessing basic properties such as high temperature resistance and wear resistance. However, with the increasing intelligence and integration of electric vehicles, existing cables are gradually revealing the following technical defects under complex operating conditions: Electric vehicles have densely packed electronic equipment (such as autonomous driving sensors, vehicle radar, and precision control systems). Traditional high-voltage cables are prone to generating electromagnetic radiation when operating at high frequencies and high voltages (especially in motor drive systems under PWM modulation), with a frequency range covering 30MHz-1GHz. This may interfere with the signal transmission of surrounding sensitive electronic components, leading to data distortion or functional failure. Simultaneously, the external electromagnetic environment (such as vehicle inverters and wireless communication equipment) may also interfere with the cable itself, affecting the stability of energy transmission. The material properties of the insulation layer (cross-linked polyolefin) and the sheath layer (polyurethane) differ significantly: the coefficient of thermal expansion of cross-linked polyolefin is approximately 1.2 × 10⁻⁻⁻⁶. 4 / ℃, while polyurethane is 2.0×10⁻ 4 At temperatures ranging from -40℃ to 150℃, under cyclic conditions (such as winter starts, summer sun exposure, or prolonged high-speed driving), thermal stress can easily cause peeling gaps between the layers. After prolonged use, the sheath layer may crack or bulge, exposing the insulation layer and increasing the risk of leakage or short circuits. The existing structure still has room for improvement in adapting to the special environment inside the vehicle: for example, drips of chemical solvents such as transmission fluid and brake fluid may cause the sheath material to swell; friction between the cable and metal bracket caused by vehicle vibration can easily lead to sheath wear; furthermore, the shielding design of traditional cables is inadequate or weak, making it difficult to meet the requirements of electromagnetic compatibility standards such as ISO 11452 for high-voltage components in vehicles.

[0004] Therefore, given the shortcomings of high-voltage cables inside electric vehicles in terms of electromagnetic compatibility, interlayer structural stability, and adaptability to complex environments, there is an urgent need to propose a high-voltage cable technology solution with optimized structure to improve the safety and reliability of the vehicle's electrical system. Utility Model Content

[0005] The main technical problem solved by this utility model is to provide a wear-resistant, tear-resistant, high-temperature resistant high-voltage cable for in-vehicle use, thereby solving one or more of the above-mentioned prior art problems.

[0006] To solve the above-mentioned technical problems, the present invention adopts a technical solution as follows: a wear-resistant, tear-resistant, high-temperature resistant high-voltage cable for vehicle interiors, the innovation of which is: it includes a conductive core made of several strands of tinned copper wires, the conductive core is covered with a heat-resistant, high and low temperature cycle-resistant, crack-resistant cross-linked polyolefin insulation layer, the insulation layer is covered with a metal shielding layer, the metal shielding layer is covered with a wear-resistant, tear-resistant, high-temperature resistant polyurethane sheathing layer, and a transition structure for enhancing the interfacial bonding force is provided between the insulation layer and the metal shielding layer.

[0007] In some embodiments, the cross-sectional area of ​​the conductive core is 1.5 mm²-120 mm², and the diameter of the tin-plated copper wire is 0.15 mm-0.20 mm.

[0008] In some implementations, the average thickness of the heat-resistant, high and low temperature cycle-resistant, crack-resistant cross-linked polyolefin insulation layer is 0.7-1.6 mm, and the thinnest part is not less than 0.56 mm.

[0009] In some embodiments, the metal shielding layer is a tin-plated copper wire braided layer or an aluminum-plastic composite tape wrapping layer, wherein the braiding density of the braided layer is not less than 85%.

[0010] In some embodiments, the transition structure is a roughened surface formed by plasma treatment on the outer surface of the insulating layer, or a coupling agent coating applied to the outer surface of the insulating layer. In some embodiments, the outer surface of the insulating layer is provided with annular grooves spaced circumferentially, the depth of the annular grooves being 0.1-0.3 mm and the width being 0.5-1.0 mm.

[0011] In some implementations, the average thickness of the abrasion-resistant, tear-resistant, and high-temperature resistant polyurethane sheath layer is 0.7-1.6 mm, and the thinnest part is not less than 0.56 mm.

[0012] In some implementations, the thickness of the metal shielding layer is 0.05mm-0.2mm, and it is electrically connected to the electric vehicle body grounding system via a grounding terminal.

[0013] The beneficial effects of this utility model are: This technical solution is applicable to the high-voltage power distribution system of pure electric vehicles and hybrid electric vehicles, and can be used as a connecting cable between the power battery and the motor controller, the charger and the battery management system, and the DC / DC converter and the low-voltage battery. It is especially suitable for high-end models with high requirements for electromagnetic compatibility and environmental resistance. Attached Figure Description

[0014] To more clearly illustrate the technical solutions in the embodiments of this utility model, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort, wherein: Figure 1 This is a schematic diagram of the structure of a wear-resistant, tear-resistant, high-temperature resistant high-voltage cable for in-vehicle use, which is a utility model.

[0015] Figure 2 This is a schematic diagram of the insulation layer of a wear-resistant, tear-resistant, high-temperature resistant high-voltage cable for in-vehicle use, according to this utility model. Detailed Implementation

[0016] The technical solutions in the embodiments of this utility model will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of this utility model, and not all of them. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model. Figure 1 and Figure 2 As shown, this utility model embodiment includes: a wear-resistant, tear-resistant, high-temperature resistant high-voltage cable for vehicle interiors, the specific implementation of which is as follows: The conductive core 100 is composed of several tinned copper wires with a diameter of 0.15mm-0.20mm twisted together. The twisting method is regular twisting or bundle twisting. The surface of each wire is tin-plated (tin layer thickness is 3-5μm), which can effectively prevent the copper wire from oxidizing and corroding in high temperature and high humidity environments. The cross-sectional area of ​​the conductive core 100 is designed from 1.5mm² to 120mm² according to the current carrying capacity requirement. For example, when the rated current of the cable is 50A, a conductive core 100 with a cross-sectional area of ​​10mm² is selected. It is composed of 37 tinned copper wires with a diameter of 0.18mm twisted together. The twisting pitch is controlled at 15-20 times the diameter of the single wire to ensure the flexibility and structural stability of the core.

[0017] The insulation layer 200 is made of XLPO (cross-linked polyolefin) material, prepared by peroxide cross-linking process, with a thickness designed to be 0.7-1.6 mm (average thickness), and the thinnest part is not less than 0.56 mm (meeting the requirements of GB / T 12706 standard for insulation eccentricity). After a 150℃ heat aging test, the tensile strength retention rate is ≥80%, the elongation at break retention rate is ≥70%, and it can withstand high and low temperature cyclic impact from -40℃ to 150℃ (no cracking after 1000 cycles), solving the problem of traditional TPE insulation materials being prone to cracking under drastic temperature changes.

[0018] A metal shielding layer 300 is added between the insulation layer 200 and the sheath layer 400, with two optional structures: Structure 1: Tin-plated copper wire braided shielding, with a single wire diameter of 0.12mm-0.15mm, a braiding density of ≥85% (coverage area ratio), and a braiding pitch of 10-15mm, providing good flexibility and shielding effect; Structure 2: Aluminum-plastic composite tape wrapped shielding, tape thickness 0.05mm-0.08mm, overlap rate ≥25%, tightly bonded to insulation layer 200 through longitudinal wrapping or wrapping process.

[0019] The shielding layer 300 needs to be connected to the electric vehicle body grounding system via copper strip or lead wire (grounding resistance ≤ 1Ω) to form a low impedance grounding loop.

[0020] To enhance the interfacial bonding between the insulating layer 200 and the metal shielding layer 300, the following two transition schemes are adopted: Option 1: The outer surface of the insulating layer 200 is treated with plasma (power 500-800W, treatment time 3-5s) to increase the surface roughness Ra to 1.5-2.0μm, thereby increasing the physical bonding force with the shielding layer 300; Option 2: Coat the surface of the insulating layer 200 with a silane coupling agent transition layer (thickness 5-10μm). One end of the coupling agent molecule reacts with the hydroxyl group of the XLPO material, and the other end forms a chemical bond with the metal shielding layer 300, thereby improving the interfacial bonding strength to ≥1.5N / cm (tested according to GB / T 2951 standard).

[0021] In addition, annular grooves 201 can be provided circumferentially on the outer surface of the insulating layer 200, with a groove depth of 0.1-0.3 mm, a width of 0.5-1.0 mm, and a spacing of 5-10 mm between adjacent grooves, to further enhance the interlayer bonding through mechanical interlocking.

[0022] The sheath layer 400 is made of 150℃ grade thermoplastic polyurethane (TPU) material with a Shore hardness of 85-90A. It is extruded over the shielding layer 300, with an average thickness of 0.7-1.6mm and a minimum thickness of not less than 0.56mm. The abrasion resistance (volume abrasion ≤50mm³ according to ISO4649 standard) and tear strength (≥80kN / m) of this material are superior to traditional PVC or rubber materials, and it can withstand long-term bending friction (such as cable and bracket contact abrasion caused by vehicle body vibration).

[0023] The working principle of the various structures in this technical solution is as follows: Conductive core 100: The tin-plated copper wire stranded structure ensures high conductivity (≥98% IACS) and oxidation resistance, adapting to the complex electrochemical environment inside the vehicle; Insulation layer 200: XLPO material forms a three-dimensional network structure through cross-linking reaction, giving the cable high temperature resistance (long-term operating temperature 125℃, short-term 150℃) and high and low temperature cycling resistance, avoiding the risk of leakage caused by insulation cracking; Metal shielding layer 300: By reflecting or absorbing electromagnetic energy, it attenuates the high-frequency electromagnetic radiation (such as the 30MHz-1GHz band) generated when the cable is working by ≥40dB, while blocking external electromagnetic interference (such as pulse signals generated by the motor controller), protecting sensitive equipment such as in-vehicle sensors and ECUs. Transition structure 500: Through physical roughening or chemical coupling, the difference in thermal expansion coefficients between the insulating layer 200 and the shielding layer 300 is resolved (XLPO thermal expansion coefficient 1.2×10⁻). 4 / ℃, Metal shielding layer (300) 1.7×10⁻ 5 To address interlayer delamination issues caused by ( / ℃), and ensure structural stability under temperature cycling; 400 sheath layer: The high abrasion resistance and tear resistance of TPU material extend the service life of the cable to more than 8 years (compared to about 5 years for traditional cables) under conditions of frequent bending and friction (such as the opening and closing of car doors causing the cable to move).

[0024] The advantages of this technical solution are as follows: This technical solution achieves the following technical effects through a five-layer synergistic design of "conductive core 100 - insulation layer 200 - shielding layer 300 - transition structure 500 - sheath layer 400": Enhanced Electromagnetic Compatibility: The 300mm metal shielding layer makes the cable compliant with the ISO 11452-2 electromagnetic compatibility standard, meeting the stringent requirements of electric vehicles for interference immunity of onboard electronic equipment; Enhanced structural reliability: The transition structure 500 increases interlaminar peel strength by more than 40%, solving the problem of interlaminar cracking under temperature cycling; Extended environmental adaptability: Combining the oil resistance (ASTM D471 standard, volume change rate ≤10% after immersion in IRM 903 oil for 168 hours) and solvent resistance of XLPO insulation and TPU sheath, it can adapt to common fluid contamination environments in vehicles, such as transmission fluid and brake fluid. Easy installation and maintenance: The 100mm tinned copper wire stranded conductive core and flexible sheath design reduce the minimum bending radius of the cable to 6 times the outer diameter (compared to 8 times for traditional cables), making it easy to lay cables in confined spaces inside the vehicle (such as the chassis and the area behind the dashboard).

[0025] This technical solution is applicable to the high-voltage power distribution system of pure electric vehicles and hybrid electric vehicles. It can be used as a connecting cable between the power battery and the motor controller, the charger and the battery management system (BMS), and the DC / DC converter and the low-voltage battery. It is especially suitable for high-end models with high requirements for electromagnetic compatibility and environmental resistance.

[0026] The above description is merely an embodiment of this utility model and does not limit the patent scope of this utility model. Any equivalent structural or procedural transformations made using the content of this utility model specification, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of this utility model.

Claims

1. A high temperature resistant, high voltage in-vehicle cable resistant to abrasion and tearing, characterized in that: It includes a conductive core (100) made of several strands of tin-plated copper wires, the conductive core (100) is covered with a heat-resistant, high and low temperature cycle-resistant, crack-resistant cross-linked polyolefin insulation layer (200), the insulation layer (200) is covered with a metal shielding layer (300), the metal shielding layer (300) is covered with a wear-resistant, tear-resistant, high temperature-resistant polyurethane sheath layer (400), and a transition structure (500) is provided between the insulation layer (200) and the metal shielding layer (300) to enhance the interfacial bonding force.

2. A high temperature resistant, high pressure resistant, abrasion resistant and tear resistant cable for in-vehicle use according to claim 1, characterized in that: The cross-sectional area of ​​the conductive core (100) is 1.5mm²-120mm², and the diameter of the tin-plated copper wire is 0.15mm-0.20mm.

3. A high temperature resistant, high pressure resistant, abrasion resistant and tear resistant cable for in-vehicle use according to claim 1, characterized in that: The average thickness of the heat-resistant, high and low temperature cycle-resistant, crack-resistant cross-linked polyolefin insulation layer (200) is 0.7-1.6 mm, and the thinnest part is not less than 0.56 mm.

4. A high temperature, high voltage, in-vehicle cable resistant to abrasion and tearing according to claim 1, characterized in that: The metal shielding layer (300) is a tin-plated copper wire braided layer or an aluminum-plastic composite tape wrapping layer, and the braiding density of the braided layer is not less than 85%.

5. A high temperature, high voltage, in-vehicle cable resistant to abrasion and tearing according to claim 1, characterized in that: The transition structure (500) is a rough surface formed by plasma treatment on the outer surface of the insulating layer (200), or a coupling agent coating applied to the outer surface of the insulating layer (200).

6. A high temperature, high voltage, in-vehicle cable resistant to abrasion and tearing according to claim 1, characterized in that: The outer surface of the insulating layer (200) is provided with annular grooves (201) spaced circumferentially, the depth of the annular grooves (201) being 0.1-0.3mm and the width being 0.5-1.0mm.

7. A high temperature, high voltage, in-vehicle cable resistant to abrasion and tearing according to claim 1, characterized in that: The average thickness of the wear-resistant, tear-resistant, and high-temperature resistant polyurethane sheath layer (400) is 0.7-1.6 mm, and the thinnest part is not less than 0.56 mm.

8. A high temperature, high voltage, in-vehicle cable resistant to abrasion and tearing according to claim 1, characterized in that: The metal shielding layer (300) has a thickness of 0.05mm-0.2mm and is electrically connected to the electric vehicle body grounding system through a grounding terminal.

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