The high-voltage system of new energy vehicles (including power battery packs, motor controllers, high-voltage wiring harnesses) is the core of vehicle power transmission. It must withstand high voltage, large current, and complex operating conditions (such as vibration, temperature fluctuations, and humid environments) during operation. The insulation protection of the high-voltage system is directly related to vehicle safety. Once insulation fails, it may cause electric leakage, short circuits, or even fire hazards. Through targeted performance design, automotive insulation materials provide a reliable insulation barrier for various components of the high-voltage system, becoming the core support for ensuring the safe operation of the system.
Core requirements of New Energy Vehicle high-voltage systems for insulation materials
The operating characteristics of new energy vehicle high-voltage systems impose multi-dimensional requirements on insulation materials. Firstly, electrical insulation performance: it must withstand the rated voltage of the system and short-term overvoltage, effectively block current conduction, and avoid electric leakage between components with different potentials. Secondly, temperature resistance: the high-voltage system generates heat during operation (such as fast charging and high-load driving), causing the temperature of battery packs and motor controllers to rise. Insulation materials must maintain stable performance within this temperature range without aging or softening. Thirdly, mechanical durability: vibrations and jolts during vehicle driving exert continuous stress on insulation materials, which need sufficient tensile and tear resistance to prevent structural damage.
Some components (such as high-voltage wiring harnesses and the inner side of battery pack casings) may come into contact with humid environments or cooling fluids. Insulation paper or sleeves must also have moisture resistance and chemical corrosion resistance to avoid degradation of insulation performance due to moisture absorption or chemical erosion, ensuring effective protection in complex usage scenarios.
Key performances and adaptation logic of automotive insulation materials
Automotive insulation materials precisely match the needs of high-voltage systems through composition and structural optimization. In terms of electrical performance, high-quality automotive insulation materials (such as NSN composite insulation paper, DuPont Nomex pure insulation paper, insulation sleeves, and insulation adhesives) have high dielectric strength and large volume resistivity, meeting the insulation class requirements of high-voltage systems. Their dielectric performance degrades slowly with temperature changes, ensuring long-term insulation reliability.
Regarding temperature resistance, materials are classified into different temperature resistance grades based on the temperature differences of application locations. For example, Sui On Insulation's NSN composite insulation paper has an insulation class of 180°C, excellent temperature resistance, mechanical performance, and dielectric strength. It is widely used in new energy vehicle drive motors for slot insulation, phase insulation, and turn-to-turn insulation, especially in oil-cooled drive motors.
In mechanical performance design, insulation materials for vibration scenarios (such as motor controller insulation gaskets) are added with reinforcing fibers to improve fatigue resistance. For components requiring bending (such as high-voltage wiring harness insulation layers), flexible substrates are adopted to ensure no cracks during bending. In terms of environmental resistance, surface coatings or material modification reduce moisture penetration, enhance resistance to cooling fluids and oil contamination, and expand adaptation scenarios.
Core application positions of automotive insulation materials in high-voltage systems
1. Insulation Scenarios for Power Battery Packs
The power battery pack is the energy core of the high-voltage system. Insulation isolation is required between cells and between cells and the casing. Automotive insulation materials can be made into insulation separators placed between cells to prevent electric leakage. They can also be made into insulation films attached to the inner side of the casing to isolate cells from the metal casing while buffering the impact of vibration on cells. Some battery packs also use insulation potting adhesives to fill gaps between cells, achieving both insulation and auxiliary heat conduction, balancing protection and heat dissipation.
2. Insulation Scenarios for Motor Controllers
Motor controllers are responsible for power conversion, requiring insulation for internal power modules, capacitors, circuit boards, and other components. Automotive insulation materials can be made into insulation gaskets clamped between power modules and heat dissipation casings, realizing electrical isolation without affecting heat dissipation. They can also be made into insulation paint applied to the surface of circuit boards to improve the temperature resistance and insulation performance of circuit boards, preventing insulation failure due to high temperature during module operation.
3. Insulation Scenarios for High-Voltage Wiring Harnesses
High-voltage wiring harnesses connect battery packs, motors, chargers, and other components, serving as current transmission channels that require full insulation. NEV insulation materials can be made into wiring harness insulation sheaths wrapping the outer layer of wires to resist external friction, moisture, and temperature changes. Insulation sleeves (such as sleeves) or insulation tapes (Nomex insulation tapes) are used at wiring harness joints to enhance insulation at the joints and avoid electric leakage risks caused by exposed joints or poor sealing.
In response to customer needs for new energy vehicle motors and power systems, Sui On Insulation can provide a variety of insulation material solutions. Based on key NEV insulation requirements (such as temperature resistance and insulation performance), we supply DuPont NOMEX, SOFLEX NHN, SOFLEX NSN, SOFLEX NKN, PEEK films, insulation sleeves, and other automotive insulation system-related products, helping customers build a safe and reliable insulation protection system for new energy vehicle high-voltage systems.
