A high-voltage aluminum alloy power line for a new energy vehicle and a preparation method thereof

Abstract

The application discloses a high-voltage aluminum alloy power line for a new energy automobile and a preparation method thereof, and belongs to a new energy automobile component. From inside to outside, the high-voltage aluminum alloy power line comprises a conductor, an insulation layer, a shielding layer and an outer sheath in sequence. The shielding layer comprises the following raw materials in mass fraction: 10-20% modified carbon black, 5-20% carbon fiber POM and the balance of silicone rubber. The preparation process of the modified carbon black comprises the following steps: step one: after carbon black, nano silicon oxide and tetraethyl orthosilicate are reacted, a SiO2 coating layer is formed on the surface of the carbon black; step two: the SiO2 coating layer is removed through acid pickling to obtain porous carbon black; and step three: after the porous carbon black and polydimethylsiloxane are mixed, the modified carbon black is obtained. The high-voltage aluminum alloy power line for the new energy automobile has excellent flexibility, insulation performance and shielding performance, and can meet the high-performance requirements of the new energy automobile field on the power line.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of new energy automobile parts, and particularly relates to a high-voltage aluminum alloy power line for a new energy automobile and a preparation method thereof. BACKGROUND

[0002] In the development process of new energy automobiles, high-voltage power lines play an indispensable role, and their main function is to transmit electric energy to drive the operation of core components such as motors. However, the current high-voltage power lines still have limitations in some aspects. For example, some power lines use traditional metal conductors, which makes them heavier, not only increasing the overall weight of the automobile, which adversely affects the improvement of the vehicle's range, but also leading to cost increases. In addition, traditional power lines may not fully meet the complex wiring needs of new energy automobiles in terms of flexibility, especially under the frequent vibration, bending and other working conditions of the vehicle, the power line is prone to damage, thereby affecting the safety and reliability of the vehicle. Therefore, it is of great practical significance to develop a high-voltage power line specially suitable for new energy automobiles, which has good softness, can achieve weight reduction and cost reduction, and has reliable performance. SUMMARY

[0003] The application is to overcome the above technical problems, and therefore provides a high-voltage aluminum alloy power line for a new energy automobile and a preparation method thereof. The new energy automobile high-voltage aluminum alloy power line of the application has excellent flexibility, insulation performance and shielding performance, and can meet the high performance requirements of power lines in the field of new energy automobiles.

[0004] The application solves the above technical problems through the following technical solutions.

[0005] A high-voltage aluminum alloy power line for a new energy automobile comprises, from inside to outside, a conductor, an insulation layer, a shielding layer and an outer sheath.

[0006] The shielding layer comprises the following mass fractions of raw materials: 10-20% modified carbon black and 5-20% carbon fiber POM, and the balance is silicone rubber.

[0007] The process for preparing the modified carbon black comprises the following steps:

[0008] Step one: after the reaction of carbon black, nano-silicon oxide and tetraethyl orthosilicate, a SiO2 coating layer is formed on the surface of the carbon black;

[0009] Step two: the SiO2 coating layer is removed by pickling to obtain porous carbon black;

[0010] Step three: after mixing the porous carbon black and polydimethylsiloxane, the modified carbon black is obtained;

[0011] The carbon black includes acetylene carbon black and rubber carbon black, and the mass ratio of the acetylene carbon black:rubber carbon black is 1:15-40, preferably 1:20-30.

[0012] In step one, the reaction process is as follows: first, the carbon black and the nano silicon oxide are dispersed in ethanol to form a suspension, then the tetraethyl orthosilicate is added, the pH is adjusted to 9-10, and the stirring reaction is carried out for 12-24 hours.

[0013] In step two, the acid washing is carried out by washing with dilute hydrochloric acid for 3-5 times, and then drying.

[0014] In step three, the mixing process is as follows: the polydimethylsiloxane is dissolved in ethanol, and then the porous carbon black is added, and the stirring is carried out under ultrasonic for 4-6 hours.

[0015] After step three, the ethanol washing is further carried out for 2-3 times, and then the solidification is carried out at 70-80℃ for 2-3 hours.

[0016] The carbon fiber POM itself has good antistatic ability and electromagnetic shielding ability, the modified carbon black and the conductive fiber POM jointly form a high-efficiency shielding network, and the electromagnetic absorption and reflection ability is enhanced. The modified carbon black has the characteristics of light weight, and the flexible molecular chain (such as PDMS) on the surface enhances the interface bonding with the matrix, and the anti-shock and bending resistance of the shielding layer is improved. Among them, the selection of rubber carbon black as the carbon black raw material can enhance the elasticity and wear resistance of the material, the acetylene carbon black has certain conductivity, and the appropriate addition of the acetylene carbon black is beneficial to improve the electromagnetic shielding ability.

[0017] The insulating layer includes the following mass fraction of raw materials: 6-9% of nano titanium dioxide, 4-7% of nano aluminum oxide, and the balance of silicone rubber; the addition of nano titanium dioxide and nano aluminum oxide can improve the insulation performance and heat resistance of the silicone rubber insulating material, so that it can withstand the high voltage and high temperature environment of the high-voltage system of the new energy vehicle, and at the same time, the aging resistance is enhanced, and the service life of the power line is prolonged.

[0018] The outer sheath includes the following mass fraction of raw materials: 9-13% of aramid fiber short cut silk, 5-9% of anti-aging additives, and the balance of silicone rubber; the addition of aramid fiber short cut silk greatly improves the mechanical strength and wear resistance of the outer sheath, and the use of anti-aging additives can enhance the aging resistance of the outer sheath, so that it can resist various external environmental factors during the driving of the new energy vehicle, such as temperature change, chemical substance corrosion, etc.

[0019] The modified carbon black comprises the following mass parts of raw materials for preparation: 100 parts of carbon black, 10-50 parts of nano silicon oxide, 10-30 parts of tetraethyl orthosilicate (TEOS), 10-20 g of polydimethylsiloxane (PDMS); preferably, the modified carbon black comprises the following mass parts of raw materials for preparation: 100 parts of carbon black, 30-50 parts of nano silicon oxide, 20-30 parts of tetraethyl orthosilicate, 15-20 parts of polydimethylsiloxane; TEOS hydrolysis and condensation can form a SiO2 coating layer on the surface of the carbon black, and PDMS is a flexible insulating coating precursor.

[0020] In some preferred embodiments, the density of the silicone rubber is 1.22-1.32 g / cm 3 . The silicone rubber is the main base material of the insulating layer, the shielding layer and the outer sheath, and the silicone rubber itself has a relatively low density, which helps to reduce the weight of the power supply line as a whole.

[0021] In some preferred embodiments, the Shore hardness of the silicone rubber is 30-34.

[0022] In some preferred embodiments, the elongation of the silicone rubber is ≥450%.

[0023] In some preferred embodiments, the tear strength of the silicone rubber is ≥7.5 kN / m.

[0024] In some preferred embodiments, the D50 of the nano titanium dioxide is 20-30 nm.

[0025] In some preferred embodiments, the specific surface area of the nano titanium dioxide is 100-200 m 2 / g.

[0026] In some preferred embodiments, the crystal form of the nano aluminum oxide is rutile.

[0027] In some preferred embodiments, the D50 of the nano aluminum oxide is 80 nm.

[0028] In some preferred embodiments, the specific surface area of the nano aluminum oxide is 15-30 m 2 / g.

[0029] In some preferred embodiments, the oil absorption value of the acetylene carbon black is 140-330 ml / 100 g.

[0030] In some preferred embodiments, the D50 of the acetylene carbon black is 10-30 nm.

[0031] In some preferred embodiments, the oil absorption value of the rubber carbon black is 30-150 mL / 100 g.

[0032] In some preferred embodiments, the rubber carbon black D50 = 20 ~ 470 nm.

[0033] In some preferred embodiments, the EMI electromagnetic shielding of the carbon fiber reinforced POM is 20 ~ 70 dB.

[0034] In some preferred embodiments, the antistatic grade of the carbon fiber reinforced POM is 10 6 ~10 10 Ω.

[0035] In the shielding layer, the density of carbon black and conductive carbon fiber POM is relatively low, which helps to reduce the weight of the shielding layer.

[0036] In some preferred embodiments, the density of the aramid fiber short cut filament is 1.40 ~ 1.45 g / cm 3 .

[0037] In some preferred embodiments, the tensile strength of the aramid fiber short cut filament is ≥ 3000 MPa.

[0038] In some preferred embodiments, the anti-aging aid is an arylamine anti-aging agent, preferably antioxidant 4010NA N - isopropyl- N' - phenyl-p-phenylenediamine, CAS No. 101-72-4) or antioxidant 4020 N - (1,3-dimethylbutyl)- N' - phenyl-p-phenylenediamine, CAS No. 793-24-8).

[0039] In some preferred embodiments, the chemical composition of the conductor is 2 ~ 4% magnesium, 1 ~ 3% silicon, 0.3 ~ 1.2% iron, 0.2 ~ 0.6% copper, and the balance of aluminum.

[0040] In some preferred embodiments, the conductor is twisted by aluminum alloy monofilament, and the maximum diameter of the monofilament is 0.31 ~ 0.51 mm.

[0041] In some preferred embodiments, the thickness of the insulating layer is 1.5 ~ 3 mm.

[0042] In some preferred embodiments, the thickness of the shielding layer is 0.8 ~ 1.8 mm.

[0043] In some preferred embodiments, the thickness of the outer sheath is 2.5 ~ 4.5 mm.

[0044] The application also discloses a preparation method of a high-voltage aluminum alloy power line of a new energy automobile, comprising the following steps:

[0045] S1. Preparing the conductor: the raw materials of the conductor are smelted and then continuously cast and rolled, drawn, stranded and annealed to obtain the conductor;

[0046] S2. Preparing the insulation layer: the raw materials of the insulation layer are heated and then extruded on the surface of the aluminum alloy conductor to obtain a first preform;

[0047] S3. Preparing the shielding layer: the raw materials of the shielding layer are heated and then extruded on the surface of the first preform to obtain a second preform;

[0048] S4. Preparing the outer sheath: the raw materials of the outer sheath are heated and then extruded on the surface of the second preform to obtain the high-voltage aluminum alloy power line for new energy vehicles.

[0049] In some preferred embodiments, the smelting temperature is 720-780℃.

[0050] In some preferred embodiments, the smelting time is ≥2h, preferably 4-6h.

[0051] In some preferred embodiments, the drawing process is divided into initial drawing, intermediate drawing and fine drawing.

[0052] In some preferred embodiments, the cooling system of the drawing is controlled at a temperature of 100-150℃.

[0053] Further, the initial drawing speed is controlled at 20-25m / min; the intermediate drawing speed is 6-10m / min; and the fine drawing speed is 8-15m / min.

[0054] In some preferred embodiments, the annealing is at 300-400℃ for 10-30min.

[0055] In some preferred embodiments, the annealing is performed by using a continuous annealing furnace and a batch annealing furnace.

[0056] In some preferred embodiments, in S2, S3 and S4, the extrusion speed is 1.5-3.5m / min.

[0057] In some preferred embodiments, in S2, the heating temperature is 160-190℃.

[0058] In some preferred embodiments, in S3, the heating temperature is 170-200℃.

[0059] In some preferred embodiments, in S4, the heating temperature is 180-210℃.

[0060] On the basis of common general knowledge in the art, the above-mentioned preferred conditions can be combined arbitrarily to obtain various preferred examples of the present application.

[0061] Compared with the prior art, the new energy vehicle high-voltage aluminum alloy power line has the beneficial effects of the present application:

[0062] In terms of material selection, the appropriate addition of nano-titanium dioxide and nano-aluminum oxide in the insulating layer can significantly improve its insulation performance, heat resistance and aging resistance without affecting the quality of the insulating layer. This improvement enables the silicone rubber to effectively cope with the high voltage and high temperature environment in the high-voltage system of new energy vehicles, thereby significantly extending the service life of the power line.

[0063] The design of the shielding layer adopts a composite material of modified carbon black and carbon fiber polyformaldehyde (POM). The two work together to build an efficient electromagnetic shielding network. In addition, the modification of carbon black further enhances the lightweight, elasticity and wear resistance of the material. Experimental results show that the shielding layer has excellent shielding performance and exhibits good stability in the bending test without the phenomenon of carbon black particle migration.

[0064] The outer sheath part significantly improves its mechanical strength and wear resistance by introducing aramid fiber short cut filaments. At the same time, the addition of anti-aging additives significantly enhances the aging resistance of the outer sheath, enabling it to effectively resist various external environmental factors faced during the driving of new energy vehicles, including temperature changes, chemical substance erosion, etc.

[0065] In summary, the new energy vehicle high-voltage aluminum alloy power line of the present application has the advantages of light weight, good flexibility, etc., and can meet the use requirements of new energy vehicles. DETAILED DESCRIPTION

[0066] In order to facilitate understanding of the present application, the following will describe the present application more comprehensively and in detail in combination with preferred embodiments, but the protection scope of the present application is not limited to the following specific embodiments.

[0067] Unless otherwise defined, all professional terms used herein have the same meaning as generally understood by those skilled in the art. The professional terms used herein are only for the purpose of describing specific embodiments and are not intended to limit the protection scope of the present application.

[0068] The ranges disclosed herein are intended to be "open" ranges, unless expressly specified otherwise. For example, a range of "1 to 10" is intended to include all whole numbers and fractions within this range, e.g., 1, 1.1, 1.2.,..., 10. Similarly, a range of "5-10" is intended to include, 5, 5.1, 5.2,..., 10. Also, the ranges disclosed herein are intended to be "inclusive" of the minimum and maximum values, unless specifically indicated otherwise. For example, a range of "between 1 and 10" is intended to include the values of 1 and 10. Also, when referring to a parameter as being an integer, it is understood that the parameter can be, for example, an integer of 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, etc.

[0069] All embodiments and optional embodiments of the present application can be combined with each other to form new technical solutions, unless otherwise specified.

[0070] All technical features and optional technical features of the present application can be combined with each other to form new technical solutions, unless otherwise specified.

[0071] All steps of the present application can be performed in sequence or randomly, preferably in sequence, unless otherwise specified. For example, the method comprises steps (a) and (b), which means that the method can comprise steps (a) and (b) in sequence, or steps (b) and (a) in sequence. For example, the method can further comprise step (c), which means that step (c) can be added to the method in any order. For example, the method can comprise steps (a), (b) and (c), or steps (a), (c) and (b), or steps (c), (a) and (b), etc.

[0072] Unless otherwise specified, "including" and "comprising" mentioned in the present application are open-ended and can also be closed-ended. For example, "including" and "comprising" can mean that other components not listed can also be included or contained, or only the listed components can be included or contained.

[0073] If not otherwise specifically defined, the term "or" in the present invention is inclusive. For example, the phrase "A or B" means "A, B, or both A and B." More specifically, any of the following satisfy the condition "A or B": A is true (or present) and B is false (or not present); A is false (or not present) and B is true (or present); or both A and B are true (or present).

[0074] The raw material information used in the following examples is as follows:

[0075] The silicone rubber is purchased from Tianxie Silicone Technology Co., Ltd. TN-5930U, which is a flame-retardant silicone rubber with a density of 1.22~1.32g / cm 3 , a Shore hardness of 30~34, an elongation of ≥450%, and a tear strength of ≥7.5kN / m.

[0076] The nano-titanium dioxide is purchased from Hangzhou Hengna New Material Co., Ltd. HN-T05, with a D50 of 20~30nm and a surface area of 100~200m 2 / g. The nano-titanium dioxide is an oil-wet white fluffy powder.

[0077] The nano-aluminum oxide is purchased from Hangzhou Hengna New Material Co., Ltd. HN-L07X, with a D50 of 80nm and a specific surface area of 15~30m 2 / g. The nano-aluminum oxide is a white powder with good thermal conductivity, which can give the rubber better compactness and abrasion resistance.

[0078] The rubber carbon black is purchased from Xinxiang Delong Chemical Co., Ltd. The rubber carbon black has an oil absorption value of 30~150mL / 100g and a D50 of 20~470nm. The rubber carbon black is collected under the condition of incomplete combustion after the cracking of coal tar or vegetable oil, the control of oil injection amount by a flame nozzle, and the control of furnace temperature. As a reinforcing material added to rubber products, it can increase the tensile strength, rigidity, grip, hardness, tear resistance, wear resistance, and other properties of the rubber products.

[0079] The polydimethylsiloxane has a Mw of 115000.

[0080] The carbon fiber-added POM is purchased from Dongguan Lelei Plastic Co., Ltd. The carbon fiber-added POM has an EMI electromagnetic shielding of 20~70dB and an antistatic grade of 10 6 ~10 10 Ω.

[0081] The aramid fiber chopped strand has a density of 1.44g / cm 3 , a tensile strength of ≥3000MPa, a tensile modulus of 80GPa, and an elongation at break of 3.6%, with a typical chopped length of 3.6mm.

[0082] Example 1

[0083] 1. The new energy vehicle high-voltage aluminum alloy power line of the present embodiment is composed of a conductor, an insulation layer (2.2 mm), a shielding layer (1.3 mm), and an outer sheath (3.5 mm).

[0084] The conductor with a maximum outer diameter of 2.79 mm is twisted by aluminum alloy monofilaments (twisted by 7 strands, each strand composed of 7 monofilaments), and the maximum diameter of the monofilament is 0.31 mm; the chemical composition of the conductor is 2.9% magnesium, 2.0% silicon, 0.80% iron, 0.4% copper, and the balance of aluminum.

[0085] The insulation layer is composed of the following mass fractions of raw materials for preparation: 7% nanometer titanium dioxide, 5% nanometer aluminum oxide, and the balance of silicone rubber.

[0086] The shielding layer is composed of the following mass fractions of raw materials for preparation: 14.3% modified carbon black and 8.2% carbon fiber POM, and the balance of silicone rubber.

[0087] The modified carbon black includes the following mass fractions of raw materials for preparation: 100 parts of carbon black, 40 parts of nanometer silicon oxide, 23 parts of tetraethyl orthosilicate, and 17 parts of polydimethylsiloxane.

[0088] The mass ratio of acetylene carbon black to rubber carbon black in the carbon black is 1:30.

[0089] The preparation process of the modified carbon black is as follows: first, disperse the carbon black and nanometer silicon oxide in 500 parts of ethanol according to the above proportions to form a suspension, then add the tetraethyl orthosilicate, adjust the pH to 9 using ammonia water, and stir for 18 h; use 0.1M dilute hydrochloric acid to wash 5 times to remove the nanometer silicon dioxide template, and dry at 60°C for 12 h to obtain porous carbon black; dissolve the polydimethylsiloxane in 200 parts of ethanol, then add the porous carbon black, and stir for 5 h under ultrasonic; after filtration, wash with ethanol for 3 times, and then solidify at 80°C for 2 h. The outer sheath is composed of the following mass fractions of raw materials for preparation: 10.9% aramid fiber short cut, 6.9% anti-aging additives, and the balance of silicone rubber.

[0090] 2. The preparation process of the new energy vehicle high-voltage aluminum alloy power line is as follows:

[0091] S1. Preparation of the conductor: melt the above-mentioned raw materials for preparation of the conductor at 750°C for 5 h, then continuously cast and roll, draw, twist, and anneal in a continuous annealing furnace at 300°C for 25 min to obtain the conductor.

[0092] The drawing process is divided into initial drawing, intermediate drawing, and fine drawing, and the cooling system temperature of the drawing is 120°C.

[0093] The initial drawing speed is controlled at 20 m / min, the intermediate drawing speed is 10 m / min, and the fine drawing speed is 10 m / min.

[0094] S2. Preparation of the insulation layer: the raw materials for preparing the insulation layer are added into an extruder and heated to 175℃ to melt, and the insulation layer is extruded on the surface of the aluminum alloy conductor through an extrusion die at an extrusion speed of 2.5 m / min to obtain a first preform;

[0095] S3. Preparation of the shielding layer: the raw materials for preparing the shielding layer are added into an extruder and heated to 185℃ to melt, and the shielding layer is extruded on the surface of the first preform through an extrusion die at an extrusion speed of 2.5 m / min to obtain a second preform;

[0096] S4. Preparation of the outer sheath: the raw materials for preparing the outer sheath are added into an extruder and heated to 195℃ to melt, and the outer sheath is extruded on the surface of the second preform to obtain a high-voltage aluminum alloy power line for new energy vehicles, which has a relative density of 5.6 kg / m 2 .

[0097] Example 2

[0098] The difference between this example and Example 1 is only that:

[0099] The chemical composition of the conductor is 3.4% magnesium, 2.49% silicon, 0.995% iron, 0.49% copper, and the balance aluminum.

[0100] The speed of the initial drawing is controlled at 6 m / min; the speed of the intermediate drawing is 7 m / min; and the speed of the fine drawing is 8 m / min.

[0101] The other steps and parameters are the same as those in Example 1.

[0102] Example 3

[0103] The difference between this example and Example 1 is that:

[0104] The insulation layer comprises the following raw materials by mass fraction: 8% nanometer titanium dioxide, 6% nanometer aluminum oxide, and the balance silicone rubber.

[0105] In S2, the heating temperature is 180℃, the extrusion speed is 3 m / min, and the thickness of the insulation layer is 2.8 mm.

[0106] The other raw materials, steps, and parameters are the same as those in Example 1.

[0107] Example 4

[0108] The difference between this example and Example 1 is that:

[0109] The insulation layer comprises the following raw materials by mass fraction: 10% nanometer titanium dioxide, 3% nanometer aluminum oxide, and the balance silicone rubber.

[0110] The other raw materials, steps, and parameters are the same as those in Example 1.

[0111] Example 5

[0112] The difference between this example and Example 1 is that:

[0113] The shielding layer comprises the following raw materials by mass fraction: 15.3% modified carbon black and 9.2% carbon fiber POM, and the balance is silicone rubber; the mass ratio of acetylene carbon black to rubber carbon black in the carbon black is 1:20.

[0114] In S3, the heating temperature is 190°C, the extrusion speed is 3 m / min, and the thickness of the shielding layer is 1.5 mm.

[0115] The other raw materials, steps and parameters are the same as in Example 1.

[0116] Example 6

[0117] The difference between this example and Example 1 is that:

[0118] The outer sheath comprises the following raw materials by mass fraction: 12% aramid fiber short cut, 8% anti-aging aid, and the balance is silicone rubber.

[0119] In S4, the heating temperature is 200°C, the extrusion speed is 3 m / min, and the thickness of the outer sheath is 4 mm.

[0120] The other raw materials, steps and parameters are the same as in Example 1.

[0121] Example 7

[0122] The difference between this example and Example 1 is that:

[0123] The drawing speed of this example is 8 m / min.

[0124] The other raw materials, steps and parameters are the same as in Example 1.

[0125] Comparative Example 1

[0126] The difference between this comparative example and Example 1 is that:

[0127] The carbon black in this comparative example is not modified, but is used directly.

[0128] The other raw materials, steps and parameters are the same as in Example 1.

[0129] Comparative Example 2

[0130] The difference between this comparative example and Example 1 is that:

[0131] The mass ratio of acetylene carbon black to rubber carbon black in the carbon black raw material in the modified carbon black is 1:50.

[0132] The other raw materials, steps and parameters are the same as in Example 1.

[0133] Comparative Example 3

[0134] The difference between the present comparative example and Example 1 is that:

[0135] The mass ratio of acetylene carbon black to rubber carbon black in the carbon black raw material of the modified carbon black is 1:10.

[0136] The other raw materials, steps and parameters are the same as those in Example 1.

[0137] Comparative Example 4

[0138] The difference between the present comparative example and Example 1 is that:

[0139] The shielding layer comprises the following mass fraction of the prepared raw materials: 15% modified carbon black and the balance of silicone rubber.

[0140] The other raw materials, steps and parameters are the same as those in Example 1.

[0141] The difference in modulus between carbon black and silicone rubber is large, and the shielding layer becomes hard without adding carbon fiber POM, and the shielding attenuation value decreases greatly.

[0142] Test Example

[0143] The new energy automobile high-voltage aluminum alloy power line prepared in the above examples and comparative examples was tested for shielding performance, insulation performance and flexibility, and the test results are shown in Table 1.

[0144]

[0145] The shielding performance test of the new energy automobile high-voltage aluminum alloy power line refers to GB / T 15217 “Measurement method for shielding attenuation of coaxial cable”, and the frequency is 1 GHz;

[0146] The insulation resistance test uses an insulation resistance tester, and the test voltage is 1500V, the temperature is 40±5℃, and the humidity is ≤70%.

[0147] The flexibility test refers to the China Robot Industry Alliance Standard CRIA000 “Industrial robot special cable”, the bending radius is ≤50mm, the cycle number is 1000 times, and whether the conductor is broken, the shielding layer, the insulation layer and the protective sleeve are damaged or not is observed.

[0148] Unless otherwise specifically indicated, all materials, reagents, instruments and equipment used in the present application are commercially available or are prepared by known methods. The above specific examples further illustrate the objects, technical solutions and advantages of the present application. It should be understood that the above examples are only specific embodiments of the present application and are not intended to limit the present application. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A high-voltage aluminum alloy power cable for new energy vehicles, comprising, from the inside to the outside, a conductor, an insulation layer, a shielding layer, and an outer sheath, characterized in that: The shielding layer comprises the following raw materials in mass fractions: 10-20% modified carbon black, 5-20% carbon fiber POM and the balance silicone rubber; The process for preparing the modified carbon black comprises the following steps: Step 1: After carbon black, nano-silicon oxide and ethyl orthosilicate react, a SiO2 coating layer is formed on the surface of carbon black; Step 2: acid washing to remove the SiO2 coating layer to obtain porous carbon black; Step 3: Mixing porous carbon black and polydimethylsiloxane to obtain modified carbon black; The carbon black includes acetylene black and rubber black, and the mass ratio of the acetylene black to the rubber black is 1:15-40.

2. The high-voltage aluminum alloy power line for new energy vehicles according to claim 1, characterized in that: The insulating layer comprises the following raw materials in mass fractions: 6-9% nano titanium dioxide, 4-7% nano aluminum oxide and the remainder silicone rubber; And / or, the outer sheath comprises the following raw materials in the following mass fractions: 9-13% aramid fiber chopped strands, 5-9% anti-aging additive and the balance silicone rubber; And / or, the modified carbon black comprises the following raw materials in parts by mass: 100 parts of carbon black, 10-50 parts of nano-silicon oxide, 10-30 parts of tetraethyl orthosilicate, and 10-20g of polydimethylsiloxane.

3. The high-voltage aluminum alloy power line for new energy vehicles according to claim 1, characterized in that: Satisfy at least one of the following conditions a to d: a. The density of the silicone rubber is 1.22~1.32g / cm 3 ; b. The Shore hardness of the silicone rubber is 30 to 34; c. The elongation of the silicone rubber is ≥450%; d. The tear strength of the silicone rubber is ≥7.5 kN / m.

4. The high-voltage aluminum alloy power line for new energy vehicles according to claim 2, characterized in that: Meet at least one of the following conditions a to e: a. The nano titanium dioxide has a D50 of 20 to 30 nm; b. The specific surface area of ​​the nano titanium dioxide is 100~200m 2 / g; c. The crystal form of the nano-alumina is rutile; d. D50 of the nano-alumina = 80nm; e. The specific surface area of ​​the nano-alumina is 15~30m 2 / g.

5. The high-voltage aluminum alloy power line for new energy vehicles according to claim 1, characterized in that: Satisfy at least one of the following conditions a to f: a. The oil absorption value of the acetylene black is 140~330ml / 100g; b. The acetylene black D50 = 10 ~ 30nm; c. The oil absorption value of the rubber carbon black is 30~150mL / 100g; d. The rubber carbon black D50 = 20 ~ 470nm; e. The EMI electromagnetic shielding of the carbon fiber POM is 20~70dB; f. The antistatic grade of the carbon fiber POM is 10 6 ~10 10 Ω.

6. The high-voltage aluminum alloy power cable for new energy vehicles according to claim 1, characterized in that: Satisfy at least one of the following conditions a~b: a. The chemical composition of the conductor is 2 to 4% magnesium, 1 to 3% silicon, 0.3 to 1.2% iron, 0.2 to 0.6% copper and the remainder aluminum; b. The conductor is made of twisted aluminum alloy monofilaments, and the maximum diameter of the monofilaments is 0.31~0.51mm.

7. The high-voltage aluminum alloy power cable for new energy vehicles according to claim 1, characterized in that: Meet at least one of the following conditions a to c: a. The thickness of the insulating layer is 1.5~3mm; b. The thickness of the shielding layer is 0.8~1.8mm; c. The thickness of the outer sheath is 2.5~4.5mm.

8. The method for preparing a high-voltage aluminum alloy power line for new energy vehicles according to any one of claims 1 to 7, wherein: The following steps are involved: S1. Preparation of a conductor: The raw materials for preparing the conductor are smelted, continuously cast and rolled, drawn, stranded and annealed to obtain a conductor; S2. Preparation of an insulating layer: After heating the raw material for preparing the insulating layer, an insulating layer is extruded on the surface of the aluminum alloy conductor to obtain a first preform; S3 preparation of the shielding layer: the shielding layer is prepared by heating the raw material after the first preform surface extruded shielding layer to obtain a second preform; S4. Preparing an outer sheath: After heating the raw materials for preparing the outer sheath, the outer sheath is extruded on the surface of the second preform to obtain a high-voltage aluminum alloy power cord for new energy vehicles.

9. The method for preparing a high-voltage aluminum alloy power line for new energy vehicles according to claim 8, wherein: Satisfy at least one of the following conditions a to d: a. The smelting temperature is 720~780 ℃, and the smelting time is ≥2h; b. The wire drawing process is divided into initial drawing, intermediate drawing and finishing drawing; the initial drawing speed is controlled at 20~25m / min; the intermediate drawing speed is 6~10m / min; the finishing drawing speed is 8~15m / min; c. The temperature of the wire drawing cooling system is controlled at 100~150°C; d. The annealing is carried out at 300-400°C for 10-30 minutes.

10. The method for preparing a high-voltage aluminum alloy power line for new energy vehicles according to claim 8, characterized in that: Satisfy at least one of the following conditions a to d: a. In S2, S3, and S4, the extrusion speed is 1.5 to 3.5 m / min respectively; b. In S2, the heating temperature is 160-190°C; c. In S3, the heating temperature is 170-200°C; d. In S4, the heating temperature is 180-210°C.

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