What are the applications of bidirectional polyimide film in the field of automotive manufacturing
Bidirectional Polyimide (BOPI) film is a high-performance polymer material made by biaxial stretching process. With core characteristics such as high temperature resistance, chemical corrosion resistance, excellent electrical insulation, high mechanical strength, and wide temperature range stability, it is suitable for the use of high temperature, vibration, and complex working conditions in autom
Bidirectional Polyimide (BOPI) film is a high-performance polymer material made by biaxial stretching process. With core characteristics such as high temperature resistance, chemical corrosion resistance, excellent electrical insulation, high mechanical strength, and wide temperature range stability, it is suitable for the use of high temperature, vibration, and complex working conditions in automobile manufacturing. Especially in the field of new energy vehicles, it is increasingly widely used and has gradually penetrated into multiple core links such as automotive electronics, power batteries, and vehicle lightweighting. It has become a key material to improve the safety, reliability, and durability of automobiles. The specific applications are as follows:
1、 New energy vehicle power battery field (core application scenarios)
Bidirectional polyimide film, with its excellent high temperature resistance, insulation, and thermal runaway resistance, has become the core material for solving the safety problems of power batteries. It is widely used in the full level protection of battery packs, covering the three core levels of cells, modules, and the entire pack, while helping to improve battery performance and service life. It is a "key barrier" for the safety of new energy vehicle batteries.
Cell level protection: The positive electrode of the cell is wrapped in a bidirectional polyimide film with a thickness of 0.05mm, partially combined with an expansion type flame retardant coating, which can form a carbonized layer at a high temperature of 180 ℃, greatly reducing thermal conductivity. At the same time, its π - π conjugation effect brings excellent insulation performance, effectively avoiding cell short circuits, delaying lithium dendrite penetration time, and reducing the risk of thermal runaway of the cell. In addition, the low water absorption rate (≤ 0.1%) of the film can block the penetration of electrolyte molecules, protect the internal structure stability of the battery cell, and improve the cycling life of the battery cell.
Module level isolation: 1mm thick bidirectional polyimide foam sandwich panel is used to replace the traditional aluminum plastic panel as the isolation component of the battery module. Under the impact of 600 ℃ flame, the rise of the back surface temperature can be controlled within 50 ℃, which is far superior to the requirements of the national standard. It can effectively block the chain transmission of thermal runaway, and strive for critical safety response time for the battery management system (BMS). According to data from Ningde Times Laboratory, battery modules equipped with this film protection can extend the thermal runaway propagation time from the traditional solution of 120 seconds to 580 seconds.
Whole package level heat insulation and insulation: the bi-directional polyimide aerogel felt is filled in the gap between the battery pack and the car body, which can control the fluctuation of the battery temperature difference to ± 2 ℃ under the environment of -40 ℃~85 ℃, which not only ensures the stability of the battery operating temperature, but also plays an auxiliary role in heat insulation. At the same time, the film can be used as an insulation liner inside the battery pack, replacing traditional insulation paper. Its corona resistance life exceeds 1000 hours under an electric field strength of 50kV/mm, which is more than 5 times that of ordinary insulation paper. It can maintain stable insulation performance under dynamic conditions such as vibration and impact.
Battery auxiliary components: As a coating material for battery separators, the bidirectional polyimide film can enhance the high-temperature resistance of the separator, and the single GWh power battery can consume up to 25 tons; At the same time, it can be used for insulation protection of the cold plate of power battery packs. After special treatment, it can still provide reliable insulation at high temperatures of 500 ℃, and has high adhesive strength to the cold plate, which is suitable for the design needs of power battery packs for companies such as BYD.
2、 Automotive electronics field (basic application scenarios)
Automotive electronic components need to work in harsh environments such as alternating high and low temperatures, vibration, and chemical corrosion for a long time. Bidirectional polyimide films, with their wide temperature range tolerance, stable insulation, and excellent mechanical properties, are widely used in various types of automotive electronic components to solve the problem of traditional films being prone to failure under extreme working conditions.
Flexible Circuit Board (FPC) Manufacturing: Bidirectional polyimide film is the core substrate of automotive flexible circuit boards, which can be used to manufacture flexible circuit boards for instrument panels, central control systems, automotive sensors, and autonomous driving related modules. Its temperature resistance range can reach -60 ℃~200 ℃. After 100 cycles of cold and heat (-40 ℃ → 150 ℃), there is still no cracking or discoloration, and the insulation resistance remains stable. It can adapt to high temperature environments in engine compartments and extremely cold climates in the north. At the same time, its lightweight characteristics can help to miniaturize and integrate automotive electronic components.
Vehicle electronic insulation and protection: used for insulation wrapping and sealing protection of vehicle ECU (electronic control unit), sensors, and vehicle wiring harnesses. The film can be made into different thickness specifications to meet the requirements of narrow gap insulation and impact resistance. It can bend with a radius of ≤ 1mm in an extremely cold environment of -40 ℃ without cracks. At a high temperature of 150 ℃, the tensile strength retention rate exceeds 80%, which can avoid the wire harness from being exposed due to low-temperature brittleness and high-temperature softening, reduce the risk of electronic failure, and lower the cost of automotive electronic after-sales maintenance.
Electronic component packaging: a packaging material used for small electronic components such as car chips, capacitors, resistors, etc. Its excellent chemical corrosion resistance can resist the erosion of chemical substances such as electrolytes and lubricants inside the car. After soaking in the electrolyte for 1000 hours, the tensile strength retention rate still exceeds 90%, which can effectively protect electronic components, extend their service life, and improve the reliability of car electronic systems.
3、 Lightweight field of body and interior (expanding application scenarios)
Bidirectional polyimide film can be compounded with materials such as carbon fiber and glass fiber to produce lightweight and high-strength composite materials, which are suitable for the development needs of lightweight automotive bodies while also considering protective performance. It is mainly used in body structural components and interior parts.
Body structural components: After being composite with composite materials, they can be used to manufacture body panels, door inner panels, chassis components, etc., replacing traditional metal materials. This can not only achieve weight reduction of the body (replacing traditional ceramic insulation solutions can reduce weight by 15kg), but also increase the range of new energy vehicles by about 2.3% (based on a 60kWh battery pack), while ensuring the strength and impact resistance of structural components, and adapting to various mechanical loads during vehicle driving.
Car interior components: Modified bidirectional polyimide film can be used to manufacture decorative panels, dashboard surfaces, seat armrests, and other parts of car interiors. It has the characteristics of wear resistance, high temperature resistance, no odor, and environmental protection. It can withstand long-term exposure to high temperatures inside the car, is not easy to age or change color, and can improve the texture and durability of the interior, meeting the requirements of environmental protection and safety for car interiors.
4、 Other auxiliary application scenarios
In addition to the core scenarios mentioned above, bidirectional polyimide films are also applied in other auxiliary processes of automotive manufacturing, enhancing product reliability with their unique properties. For example, the sealing and insulation components used for car lights can withstand high temperatures during operation, avoiding water ingress and fogging caused by seal failure; Insulation pads used for automotive braking and steering systems, which can maintain stable insulation in high temperature and high pressure environments, ensuring the safe operation of braking and steering systems; At the same time, it can be used as a wrapping film for automotive wiring harnesses, replacing traditional PET films, improving the temperature and wear resistance of wiring harnesses, and reducing wiring harness failures.
WeChat number：
Home
Product
Wechat
Telephone