High square resistance high voltage thin film capacitor for new energy vehicles and manufacturing process thereof

Abstract

The application relates to the technical field of new energy vehicles, and discloses a high-impedance high-voltage thin film capacitor for a new energy vehicle and a manufacturing process thereof, which comprises a shell, a plurality of groups of cores are mounted on the inner wall of the shell, positive busbars and negative busbars are respectively connected to the surfaces of the plurality of groups of cores, positive wire harnesses and negative wire harnesses are respectively connected to the positive busbars and the negative busbars, insulating paper is arranged between the positive busbars, the negative busbars and the cores, and a plugging block is arranged on the side of the shell close to the positive busbars and the negative busbars. In the application, the shell is sleeved on a hollow column through the setting of an auxiliary device, then buffer part one cooperates with buffer part two to perform buffering work, the overall structure can be damped and protected, potential damage of internal wall components caused by vibration can be significantly reduced, meanwhile, the external heat conduction piece can absorb heat and transmit the heat to the bottom plate, a gap is left between the bottom plate and the shell, air circulation is facilitated, the heat conduction block and the heat conduction sheet can dissipate heat, and the heat dissipation effect is improved.

Description

Technical Field

[0001] This invention relates to the field of new energy vehicle technology, specifically to high sheet resistance high voltage film capacitors for new energy vehicles and their manufacturing process. Background Technology

[0002] New energy vehicles are automobiles that use unconventional fuels (such as electricity and hydrogen) or new power systems, possessing energy-saving and low-pollution characteristics. They are categorized by power source into battery electric vehicles (BEVs), plug-in hybrid electric vehicles (PHEVs), and fuel cell electric vehicles (FCEVs). Core technologies encompass the three core components of the electric drive system (battery, motor, and electronic control), using electric motors to drive vehicles instead of traditional internal combustion engines, thus reducing carbon emissions.

[0003] Thin-film capacitors for new energy vehicles are key electronic components used in the power electronic systems of new energy vehicles. They use polyester (PET) films as dielectrics, with zinc, aluminum and other metals deposited on the surface to form electrodes. The capacitors are then wound or stacked to form the core, and then encapsulated in an insulating shell. They have low equivalent series resistance (ESR) and inductance (ESL), and can work stably at high frequencies of 10-200kHz. They can filter out electromagnetic interference generated by inverters, motor drives, etc., and support the efficient operation of the electric drive system.

[0004] In existing technologies, after the film capacitors used in new energy vehicles are installed, vibrations generated during vehicle operation are transmitted to the capacitor's casing. This continuous vibration not only causes mechanical stress on the capacitor casing, but more importantly, it also affects the internal core and other key components. Over time, these components are prone to structural loosening, material fatigue, or even localized damage under repeated vibrations, significantly reducing the overall lifespan of the capacitor. This internal damage may also affect the capacitor's electrical performance and operational stability, leading to performance fluctuations or failures during actual operation, thus posing a potential threat to the reliability and safety of new energy vehicles.

[0005] Therefore, we propose high sheet resistance high voltage film capacitors for new energy vehicles and their manufacturing process. Summary of the Invention

[0006] (a) Technical problems to be solved

[0007] To address the shortcomings of existing technologies, this invention provides a high sheet resistance high voltage film capacitor for new energy vehicles and its manufacturing process, thus solving the problems mentioned in the background.

[0008] (II) Technical Solution

[0009] To achieve the above objectives, the present invention provides the following technical solution: a high sheet resistance high voltage film capacitor for new energy vehicles, comprising a housing, wherein the inner wall of the housing is fitted with multiple sets of cores, the surfaces of the multiple sets of cores are respectively connected to a positive busbar and a negative busbar, a positive wire harness and a negative wire harness are respectively connected to the positive busbar and the negative busbar, insulating paper is provided between the positive busbar, the negative busbar and the cores, a sealing block is provided on the side of the housing near the positive busbar and the negative busbar, the inner wall of the housing is potted with potting compound, multiple nut brackets are installed on the inner wall of the housing, and auxiliary devices are provided on the surface of the housing;

[0010] The auxiliary device includes a base plate located below the outer casing. Multiple hollow columns are fixedly connected to the inner wall of the base plate. These hollow columns are inserted into the inner wall of the outer casing. Hollow threaded sleeves are provided on the inner walls of the hollow columns. Buffer section one and buffer section two are respectively provided on the hollow columns and the hollow threaded sleeves. An external heat-conducting component is installed on the lower surface of the outer casing. This external heat-conducting component contacts the base plate. A pressing component is also provided on the surface of the base plate to improve the stability of the contact between the external heat-conducting component and the base plate. Through these components, during installation, mounting bolts can be passed through the hollow threaded sleeves and hollow sleeves to achieve the installation connection. When the outer casing is subjected to vibration, it can move on the hollow columns. Buffer section one and buffer section two can provide cushioning protection. Simultaneously, the external heat-conducting component can absorb the overall heat and conduct it to the base, achieving rapid heat dissipation.

[0011] Preferably, the external heat-conducting component includes a heat-conducting block and multiple heat-conducting sheets. The multiple heat-conducting sheets are bolted to the surface of the heat-conducting block, with one side in contact with the base plate. Through the above components, the heat-conducting block and multiple heat-conducting sheets can transfer heat to the base plate to achieve heat dissipation. At the same time, when the outer shell moves in the hollow column, the heat-conducting sheets can deform to provide cushioning.

[0012] Preferably, the pressing assembly includes a first pressing block and a second pressing block located above the base plate. The first pressing block and the second pressing block are mounted on the base plate by screws. With the above components, the first pressing block and the second pressing block can be pressed onto the heat-conducting sheet at the corresponding position. Then, the first pressing block and the second pressing block are installed to the base plate by screws. The first pressing block and the second pressing block can cooperate with the base plate to clamp the heat-conducting sheet, thereby improving stability.

[0013] Preferably, both the heat-conducting block and the heat-conducting sheet are made of copper.

[0014] Preferably, the surfaces of the first and second pressing blocks are provided with multiple grooves for the heat-conducting sheet to be inserted. Through the above-mentioned components, the multiple grooves on the surfaces of the first and second pressing blocks can limit the heat-conducting sheet.

[0015] Preferably, the buffer part includes a fixed ring fixed on the surface of the hollow column, a buffer spring is sleeved on the surface of the hollow column, a movable ring is sleeved on the surface of the hollow column, and the two ends of the buffer spring are fixedly connected to the surfaces of the movable ring and the fixed ring, respectively.

[0016] Preferably, the second buffer part includes a second buffer spring fixed to the surface of the hollow threaded sleeve, and a collar is fixedly connected to the other end of the second buffer spring. Both the second buffer spring and the collar are sleeved and connected to the hollow column.

[0017] Preferably, an aluminum plate is provided on the potting compound, the aluminum plate is in contact with the inner wall of the outer shell, and a thermally conductive sticker is attached to the upper surface.

[0018] Preferably, the potting compound is epoxy resin.

[0019] The manufacturing process for high sheet resistance, high voltage film capacitors for new energy vehicles includes the following steps:

[0020] Step 1: Develop a nano-ceramic particle-modified polypropylene-based composite dielectric film. Combining surface functionalization coating technology, overcome the bottlenecks of leakage current control and aging resistance of traditional film materials under high voltage. A melt blending + biaxial stretching process is used to prepare a nano-Al2O3 / PP composite film. By optimizing parameters such as screw speed (200-300 r / min) and temperature gradient (zone 1 180℃, zone 2 200℃, zone 3 220℃), nanoscale dispersion of nanoparticles in the PP matrix (dispersion ≥ 98%) is achieved. Simultaneously, a surface modifier (such as silane coupling agent KH-560) is introduced to treat the nanoparticles, enhancing their interfacial bonding with the PP matrix, thereby stabilizing the bulk resistivity of the film at 10¹⁰. 4 Above Ω·cm, dielectric strength reaches 220kV / mm;

[0021] Step 2: A zinc-aluminum composite metallization layer and laser precision etching segmented electrode design are adopted to balance high sheet resistance and self-healing ability, effectively suppressing edge breakdown and electrode migration. Based on the existing vacuum evaporation equipment, a magnetron sputtering device is added. By adjusting the power ratio of Zn target and Al target (8:2), the Zn content in the alloy layer is precisely controlled at 85%-90%. In the laser etching process, a femtosecond laser processing system is introduced, and the etching accuracy reaches ±0.5μm, ensuring that the segmented electrode width is controlled at 50μm and the spacing is 200μm. After completing the laboratory research and development, 100,000 electrodes are produced on the pilot production line. The electrode performance is monitored in real time using online detection equipment such as film thickness gauges and sheet resistance testers to verify the stability of the process.

[0022] Step 3: The low parasitic parameter multilayer stacked structure and the integrated thermally conductive and weather-resistant potting process realize the high-frequency performance optimization and automotive-grade environmental adaptability of the capacitor, meeting the integration requirements of lightweight and high power density of new energy vehicles;

[0023] Step 4: Establish a professional testing platform: Use a Keysight E4980A impedance analyzer to perform wideband impedance testing from 100Hz to 10MHz with an accuracy of ±0.1%; use a customized DC withstand voltage testing system to achieve a leakage current resolution of 1nA under 1000V DC voltage; conduct accelerated life tests on the samples, continuously testing for 5000 hours under 85℃ / 80% rated voltage conditions, requiring capacity decay ≤8% and loss change ≤15%; and establish a Weibull distribution lifetime prediction model based on the test data to ensure the accuracy of the B10 lifetime prediction ≥15 years.

[0024] In summary, the technical effects and advantages of this invention are as follows:

[0025] 1. In this invention, by setting an auxiliary device, the outer shell is fitted onto the hollow column, and then the first buffer part cooperates with the second buffer part to perform buffering work, which can provide shock absorption and protection for the overall structure, thereby significantly reducing the potential damage to the inner wall components caused by vibration. At the same time, the external heat-conducting component can absorb heat and transfer the heat to the base plate. A gap is left between the base plate and the outer shell to facilitate air circulation, facilitate heat dissipation of the heat-conducting block and heat-conducting sheet, and improve the heat dissipation effect.

[0026] 2. In this invention, one end of multiple heat-conducting sheets contacts the base plate, which can form a support between the heat-conducting block and the base plate, and can cooperate to buffer and improve the buffering effect.

[0027] 3. In this invention, by setting up a pressing component, the first pressing block and the second pressing block can be installed on the base plate by screws. The grooves on the surface of the first pressing block and the second pressing block limit the heat-conducting sheet, and at the same time, they work with the base plate to clamp the heat-conducting sheet, thereby improving stability.

[0028] 4. In this invention, a nanocomposite polypropylene film is used as the insulating medium, utilizing its high resistivity (≥10¹⁰). 4 With high dielectric strength (≥200kV / mm) and high Ω·cm, efficient charge storage is achieved under high voltage conditions of 800V+; the zinc-aluminum composite segmented metallized electrode achieves high sheet resistance (≥10 Ω·cm) through a high sheet resistance design. 4 (Ω / □) Reduces leakage current and, combined with a self-healing mechanism, quickly isolates local breakdown points to ensure stable power conduction; Low parasitic parameter stacked structure and high thermal conductivity packaging process optimize high-frequency ripple (10-100kHz) filtering performance, suppress electromagnetic interference, and achieve reliable operation in a wide temperature range of -40℃ to +125℃, providing stable power support for electric drive systems and on-board charging equipment. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of the overall structure of the high sheet resistance high voltage film capacitor for new energy vehicles according to the present invention.

[0030] Figure 2 This is a schematic diagram of the high sheet resistance high voltage film capacitor for new energy vehicles from another perspective.

[0031] Figure 3 This is a partial structural schematic diagram of the high sheet resistance high voltage film capacitor for new energy vehicles according to the present invention.

[0032] Figure 4 This is a partial bottom view of the high sheet resistance high voltage film capacitor for new energy vehicles according to the present invention.

[0033] Figure 5 This is a schematic diagram of the base plate structure of the high sheet resistance high voltage film capacitor for new energy vehicles according to the present invention.

[0034] Figure 6 This invention relates to a high sheet resistance, high voltage thin-film capacitor for new energy vehicles. Figure 5 Schematic diagram of the structure at point A in the middle;

[0035] Figure 7 This is a schematic diagram of the exploded structure of the hollow column of the high sheet resistance high voltage film capacitor for new energy vehicles according to the present invention.

[0036] In the diagram: 1. Outer shell; 2. Core; 3. Positive busbar; 4. Negative busbar; 5. Positive wire harness; 6. Negative wire harness; 7. Aluminum plate; 8. Thermal conductive pad; 9. Encapsulating adhesive; 10. Insulating paper; 11. Sealing block; 12. Auxiliary device; 121. Base plate; 122. Hollow column; 123. External thermal conductive component; 1231. Thermal conductive block; 1232. Thermal conductive sheet; 124. First pressure block; 125. Second pressure block; 126. Groove; 127. Buffer part one; 1271. Fixing ring; 1272. Buffer spring one; 1273. Movable ring; 128. Buffer part two; 1281. Buffer spring two; 1282. Collar; 129. Hollow threaded sleeve; 13. Nut bracket. Detailed Implementation

[0037] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0038] refer to Figures 1-7The high sheet resistance high voltage film capacitor for new energy vehicles shown includes a housing 1. The inner wall of the housing 1 is fitted with multiple sets of cores 2. The surfaces of the multiple sets of cores 2 are respectively connected to positive busbars 3 and negative busbars 4. Positive wire harnesses 5 and negative wire harnesses 6 are respectively connected to positive busbars 3 and negative busbars 4. Insulating paper 10 is provided between positive busbars 3, negative busbars 4 and cores 2. A sealing block 11 is provided on the side of the housing 1 near the positive busbars 3 and negative busbars 4. The inner wall of the housing 1 is filled with potting compound 9. An aluminum plate 7 is provided on the potting compound 9. The aluminum plate 7 is in contact with the inner wall of the housing 1 and a thermal conductive sticker 8 is pasted on its upper surface. The potting compound 9 is epoxy resin. Multiple nut brackets 13 are installed on the inner wall of the housing 1. An auxiliary device 12 is provided on the surface of the housing 1.

[0039] The auxiliary device 12 includes a base plate 121 located below the outer casing 1. Multiple hollow columns 122 are fixedly connected to the inner wall of the base plate 121, and these hollow columns 122 are inserted into the inner wall of the outer casing 1. Hollow threaded sleeves 129 are provided on the inner walls of the hollow columns 122. Buffer portions 127 and 128 are respectively provided on the hollow columns 122 and the hollow threaded sleeves 129. An external heat-conducting component 123 is installed on the lower surface of the outer casing 1, and the external heat-conducting component 123 contacts the base plate 121. A pressing component is also provided on the surface of the base plate 121 to improve the stability of the contact between the external heat-conducting component 123 and the base plate 121. The first buffer part 127 includes a fixed ring 1271 fixed on the surface of the hollow column 122, a first buffer spring 1272 sleeved on the surface of the hollow column 122, and a movable ring 1273 sleeved on the surface of the hollow column 122. The two ends of the first buffer spring 1272 are fixedly connected to the surfaces of the movable ring 1273 and the fixed ring 1271, respectively. The second buffer part 128 includes a second buffer spring 1281 fixed on the surface of the hollow threaded sleeve 129, and a collar 1282 fixedly connected to the other end of the second buffer spring 1281. Both the second buffer spring 1281 and the collar 1282 are sleeved and connected to the hollow column 122.

[0040] In the embodiment: During installation, the installation connection can be achieved by passing the mounting bolt through the hollow threaded sleeve 129 and the hollow sleeve. When the outer shell 1 is vibrated, it can move on the hollow column 122. The first buffer part 127 and the second buffer part 128 can provide buffer protection. At the same time, the external heat-conducting component 123 can absorb the overall volume and conduct it to the base to achieve rapid heat dissipation.

[0041] The external heat-conducting component 123 includes a heat-conducting block 1231 and multiple heat-conducting sheets 1232. The multiple heat-conducting sheets 1232 are mounted on the surface of the heat-conducting block 1231 by bolts, and one side is in contact with the base plate 121. Both the heat-conducting block 1231 and the heat-conducting sheets 1232 are made of copper.

[0042] In this embodiment, the heat-conducting block 1231, together with multiple heat-conducting sheets 1232, can transfer heat to the base plate 121 to achieve heat dissipation. At the same time, when the outer shell 1 moves in the hollow column 122, the heat-conducting sheets 1232 can deform to provide cushioning.

[0043] The pressing assembly includes a first pressing block 124 and a second pressing block 125 located above the base plate 121. The first pressing block 124 and the second pressing block 125 are mounted on the base plate 121 by screws. The surfaces of the first pressing block 124 and the second pressing block 125 are provided with multiple grooves 126 for the heat-conducting sheet 1232 to be inserted.

[0044] In this embodiment: the first pressing block 124 and the second pressing block 125 can be pressed onto the heat-conducting sheet 1232 at the corresponding position. Then, the first pressing block 124 and the second pressing block 125 are installed on the base plate 121 by screws. The first pressing block 124 and the second pressing block 125 can cooperate with the base plate 121 to clamp the heat-conducting sheet 1232. The multiple grooves 126 on the surface of the first pressing block 124 and the second pressing block 125 can limit the position of the heat-conducting sheet 1232 and improve stability.

[0045] Working principle: In use, the hollow column 122 is inserted into the inner wall of the outer casing 1. Then, the hollow threaded sleeve 129 is connected to the inner wall of the hollow column 122, so that the movable ring 1273 and the collar 1282 are pressed onto the outer casing 1. Then, the first pressing block 124 and the second pressing block 125 are pressed onto the heat-conducting plate 1232 at the corresponding positions. Then, the first pressing block 124 and the second pressing block 125 are installed to the base plate 121 with screws. The first pressing block 124 and the second pressing block 125 can cooperate with the base plate 121 to clamp the heat-conducting plate 1232. The multiple grooves 126 on the surface of the first pressing block 124 and the second pressing block 125 can realize the pressing of the heat-conducting plate 1232. For limiting the position, when the whole assembly needs to be fixed, the mounting bolts can be passed through the hollow threaded sleeve 129 and the hollow sleeve to achieve the installation connection. When the outer shell 1 is subjected to vibration, the outer shell 1 can move up and down on the hollow column 122. The buffer springs 1272 and 1281 in the buffer part 127 and buffer part 228 can provide buffer protection. At the same time, when the outer shell 1 moves in the hollow column 122, the heat-conducting plate 1232 can deform to cooperate in buffering. In addition, the heat-conducting block 1231, together with multiple heat-conducting plates 1232, can draw in the whole assembly. At the same time, the heat-conducting plates 1232 transfer heat to the base plate 121 to achieve a rapid heat conduction effect.

[0046] The manufacturing process for high sheet resistance, high voltage film capacitors for new energy vehicles includes the following steps:

[0047] Step 1: Develop a nano-ceramic particle-modified polypropylene-based composite dielectric film. Combining surface functionalization coating technology, overcome the bottlenecks of leakage current control and aging resistance of traditional film materials under high voltage. A melt blending + biaxial stretching process is used to prepare a nano-Al2O3 / PP composite film. By optimizing parameters such as screw speed (200-300 r / min) and temperature gradient (zone 1 180℃, zone 2 200℃, zone 3 220℃), nanoscale dispersion of nanoparticles in the PP matrix (dispersion ≥ 98%) is achieved. Simultaneously, a surface modifier (such as silane coupling agent KH-560) is introduced to treat the nanoparticles, enhancing their interfacial bonding with the PP matrix, thereby stabilizing the bulk resistivity of the film at 10¹⁰. 4 Above Ω·cm, dielectric strength reaches 220kV / mm;

[0048] Step 2: A zinc-aluminum composite metallization layer and laser precision etching segmented electrode design are adopted to balance high sheet resistance and self-healing ability, effectively suppressing edge breakdown and electrode migration. Based on the existing vacuum evaporation equipment, a magnetron sputtering device is added. By adjusting the power ratio of Zn target and Al target (8:2), the Zn content in the alloy layer is precisely controlled at 85%-90%. In the laser etching process, a femtosecond laser processing system is introduced, and the etching accuracy reaches ±0.5μm, ensuring that the segmented electrode width is controlled at 50μm and the spacing is 200μm. After completing the laboratory research and development, 100,000 electrodes are produced on the pilot production line. The electrode performance is monitored in real time using online detection equipment such as film thickness gauges and sheet resistance testers to verify the stability of the process.

[0049] Step 3: The low parasitic parameter multilayer stacked structure and the integrated thermally conductive and weather-resistant potting process realize the high-frequency performance optimization and automotive-grade environmental adaptability of the capacitor, meeting the integration requirements of lightweight and high power density of new energy vehicles;

[0050] Step 4: Establish a professional testing platform: Use a Keysight E4980A impedance analyzer to perform wideband impedance testing from 100Hz to 10MHz with an accuracy of ±0.1%; use a customized DC withstand voltage testing system to achieve a leakage current resolution of 1nA under 1000V DC voltage; conduct accelerated life tests on the samples, continuously testing for 5000 hours under 85℃ / 80% rated voltage conditions, requiring capacity decay ≤8% and loss change ≤15%; and establish a Weibull distribution lifetime prediction model based on the test data to ensure the accuracy of the B10 lifetime prediction ≥15 years.

[0051] Nano-ceramic modified PP film with surface functional coating, volume resistivity ≥10¹ 4 Ω・cm, dielectric strength ≥200kV / mm, solving the problems of high voltage leakage current and aging.

[0052] Zinc-aluminum composite metallization layer + laser segmented etching, sheet resistance 10-20Ω / □, single self-healing energy ≤0.5J, suppressing edge breakdown and electrode migration.

[0053] The low parasitic stacked structure (ESL≤5nH) and high thermal conductivity potting compound are suitable for a wide temperature range of -40℃ to +125℃, achieving high frequency, low loss and structural stability.

[0054] A wide-band high-voltage testing platform combined with failure mechanism modeling predicts B10 lifespan of ≥15 years, covering multiple failure modes including electrical, thermal, and mechanical aspects.

[0055] Parasitic parameter coupling design + ultra-thin and lightweight structure, energy density ≥6J / cm³, volume reduction of 30%, adaptable to the miniaturization requirements of 800V platform.

[0056] Working principle: Using a nano-composite polypropylene film as the insulating medium, utilizing its high resistivity (≥10¹⁰) 4 With high dielectric strength (≥200kV / mm) and high Ω·cm, efficient charge storage is achieved under high voltage conditions of 800V+; the zinc-aluminum composite segmented metallized electrode achieves high sheet resistance (≥10 Ω·cm) through a high sheet resistance design. 4 (Ω / □) Reduces leakage current and, combined with a self-healing mechanism, quickly isolates local breakdown points to ensure stable power conduction; Low parasitic parameter stacked structure and high thermal conductivity packaging process optimize high-frequency ripple (10-100kHz) filtering performance, suppress electromagnetic interference, and achieve reliable operation in a wide temperature range of -40℃ to +125℃, providing stable power support for electric drive systems and on-board charging equipment.

[0057] All electrical components mentioned in this article are connected to an external main controller and 220V AC mains power, and the main controller can be a conventional known device such as a computer that can control it.

[0058] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A high sheet resistance high voltage film capacitor for new energy vehicles, comprising a casing (1), characterized in that: The inner wall of the outer shell (1) is equipped with multiple sets of cores (2). The surfaces of the multiple sets of cores (2) are respectively connected to positive busbars (3) and negative busbars (4). Positive wire harnesses (5) and negative wire harnesses (6) are respectively connected to the positive busbars (3) and negative busbars (4). Insulating paper (10) is provided between the positive busbars (3), negative busbars (4) and cores (2). A sealing block (11) is provided on the side of the outer shell (1) near the positive busbars (3) and negative busbars (4). The inner wall of the outer shell (1) is filled with potting compound (9). Multiple nut brackets (13) are installed on the inner wall of the outer shell (1). An auxiliary device (12) is provided on the surface of the outer shell (1). The auxiliary device (12) includes a base plate (121) located below the outer shell (1). A plurality of hollow columns (122) are fixedly connected to the inner wall of the base plate (121). The hollow columns (122) are inserted into the inner wall of the outer shell (1). A hollow threaded sleeve (129) is provided on the inner wall of the hollow column (122). A buffer part one (127) and a buffer part two (128) are respectively provided on the hollow column (122) and the hollow threaded sleeve (129). An external heat-conducting component (123) is installed on the lower surface of the outer shell (1). The external heat-conducting component (123) is in contact with the base plate (121). A pressing component is also provided on the surface of the base plate (121) to improve the contact stability between the external heat-conducting component (123) and the base plate (121).

2. The high sheet resistance high voltage film capacitor for new energy vehicles according to claim 1, characterized in that: The external heat-conducting component (123) includes a heat-conducting block (1231) and a plurality of heat-conducting sheets (1232). The plurality of heat-conducting sheets (1232) are mounted on the surface of the heat-conducting block (1231) by bolts, and one side is in contact with the base plate (121).

3. The high sheet resistance high voltage film capacitor for new energy vehicles according to claim 2, characterized in that: The pressing assembly includes a first pressing block (124) and a second pressing block (125) located above the base plate (121), the first pressing block (124) and the second pressing block (125) being mounted on the base plate (121) by screws.

4. The high sheet resistance high voltage film capacitor for new energy vehicles according to claim 2, characterized in that: Both the heat-conducting block (1231) and the heat-conducting sheet (1232) are made of copper.

5. The high sheet resistance high voltage film capacitor for new energy vehicles according to claim 3, characterized in that: The surfaces of the first pressure block (124) and the second pressure block (125) are provided with multiple grooves (126) for the heat-conducting sheet (1232) to be inserted.

6. The high sheet resistance high voltage film capacitor for new energy vehicles according to claim 1, characterized in that: The buffer section (127) includes a fixed ring (1271) fixed on the surface of the hollow column (122), a buffer spring (1272) sleeved on the surface of the hollow column (122), a movable ring (1273) sleeved on the surface of the hollow column (122), and the two ends of the buffer spring (1272) are fixedly connected to the surfaces of the movable ring (1273) and the fixed ring (1271) respectively.

7. The high sheet resistance high voltage film capacitor for new energy vehicles according to claim 1, characterized in that: The second buffer section (128) includes a second buffer spring (1281) fixed on the surface of the hollow threaded sleeve (129). The other end of the second buffer spring (1281) is fixedly connected to a collar (1282). Both the second buffer spring (1281) and the collar (1282) are sleeved and connected to the hollow column (122).

8. The high sheet resistance high voltage film capacitor for new energy vehicles according to claim 1, characterized in that: An aluminum plate (7) is provided on the potting compound (9), the aluminum plate (7) is in contact with the inner wall of the outer shell (1), and a thermally conductive sticker (8) is pasted on its upper surface.

9. The high sheet resistance high voltage film capacitor for new energy vehicles according to claim 1, characterized in that: The potting compound (9) is epoxy resin.

10. A manufacturing process for high sheet resistance high voltage thin-film capacitors for new energy vehicles, characterized in that, Includes the following steps: S1: Develop a polypropylene-based composite dielectric film modified with nano-ceramic particles. Combining this with surface functionalized coating technology, overcome the bottlenecks of leakage current control and aging resistance of traditional film materials under high voltage. A melt blending + biaxial stretching process is used to prepare nano-Al2O3 / PP composite films. By optimizing parameters such as screw speed (200-300 r / min), temperature gradient (180℃ in zone I, 200℃ in zone II, and 220℃ in zone III), nanoscale dispersion of nanoparticles in the PP matrix is ​​achieved, with a dispersion degree ≥98%. Simultaneously, a surface modifier is introduced to treat the nanoparticles, enhancing their interfacial bonding with the PP matrix, thereby stabilizing the bulk resistivity of the film at 10¹⁰. 4 Above Ω·cm, dielectric strength reaches 220kV / mm; S2: Employing a zinc-aluminum composite metallization layer and laser precision etching segmented electrode design, it balances high sheet resistance characteristics with self-healing capabilities, effectively suppressing edge breakdown and electrode migration. Based on the existing vacuum evaporation equipment, a magnetron sputtering device is added. By adjusting the power ratio of Zn target to Al target to 8:2, the Zn content in the alloy layer is precisely controlled at 85%-90%. In the laser etching process, a femtosecond laser processing system is introduced, achieving an etching accuracy of ±0.5μm, ensuring that the segmented electrode width is controlled at 50μm and the spacing is 200μm. After completing laboratory research and development, 100,000 electrodes are produced on a pilot production line. Online testing equipment such as film thickness gauges and sheet resistance testers are used to monitor electrode performance in real time and verify process stability. S3: The low parasitic parameter multilayer stacked structure and the integrated thermally conductive and weather-resistant potting process realize the high-frequency performance optimization and automotive-grade environmental adaptability of the capacitor, meeting the integration requirements of lightweight and high power density of new energy vehicles; S4: Establish a professional testing platform: Use a Keysight E4980A impedance analyzer to perform wideband impedance testing from 100Hz to 10MHz with an accuracy of ±0.1%; use a customized DC withstand voltage testing system to achieve a leakage current resolution of 1nA under 1000V DC voltage; conduct accelerated life tests on samples, continuously testing for 5000 hours under 85℃ / 80% rated voltage conditions, requiring capacity decay ≤8% and loss change ≤15%; and establish a Weibull distribution lifetime prediction model based on the test data to ensure the accuracy of the B10 lifetime prediction ≥15 years.

Images