Electric vehicles are currently in a rapid development path. The “Global Electric Vehicle Development Index Research Report 2018” states that China ’s electric vehicle and battery production grew rapidly and had high expectations last year, continuing to maintain its global leadership. At this stage, the development mission of new energy vehicles is longer battery life, lower cost and faster charging speed. The advantages of China's electric vehicle industry in the industry and market have become a powerful driving force for technological progress.
Compared with non-vehicle chargers, the advantage of having a car charger is that the vehicle can be easily charged using an AC power outlet. However, it also requires that vehicles have a certain weight of power electronics and radiators.
Newer on-board charger (OBC) designs have been integrated with multiple functions, including bi-directional power conversion and AC-to-DC conversion, which requires the overall design of OBC to be more compact. However, the compact design also brings some problems. Integrated, multi-function chargers will generate additional power loads due to AC-DC conversion, and the "thermal management" problem of on-board chargers (OBCs) has become increasingly serious. .
In order to ensure that the above thermal load is in full contact with the inner wall of the shell of the metal mold to effectively achieve heat conduction, a "thermal management" material that not only provides excellent thermal conductivity, but also must have good electrical insulation properties to fill the device and heat sink Gap between surfaces. At present, the more commonly used "thermal management" material solution for OBC is the use of silicone thermal conductive encapsulant.
However, the current organic silicone encapsulation scheme has the following unavoidable defects:
High thermal conductivity silicone rubber is expensive, and the price is hundreds or even thousands per kilogram (and the density is large, and the amount of glue used per unit volume) has further pushed up the production cost and the consumer's use cost, which inhibited the rapid development of the electric vehicle industry. Promotion.
Silicone changes the viscosity and hardness of silicone by adding silicone oil. The presence of silicone oil causes electronic components, especially those connected through sockets, to be prone to poor contact, leading to failure of the charging system.
Due to the low bonding strength between the silicone rubber and the metal, the potted silicone rubber may be peeled from the metal case of the charging system, thereby affecting the sealing and heat conduction effect, resulting in product performance degradation or failure.
High thermal conductivity organic silica gel generally has high viscosity and is difficult to process. It requires extremely high equipment and automated production equipment is expensive. At present, manual gluing or semi-automatic manual operation is generally used, which is extremely inefficient.
Rampo has been customizing and producing electronic potting systems based on customer needs for more than 35 years. Customer-oriented, high professional level and full commitment: Supporting customers during product development and production is a natural part of RAMPF Polymer Solutions' work.
The newly developed high thermal conductivity potting polyurethane material solution developed by the German blue pool company perfectly solves the shortcomings of high thermal conductivity silicone in terms of cost, processing and performance. Once launched, it has been recognized by the market and widely used by customers. Not only in the emerging OBC projects, but also in the field of inverter capacitor coil encapsulation, which was widely used in the past, the use of silicone is being phased out.
Currently, more RAKU-PUR models are used as follows:
Product model Test standard 21-2350 A 21-2080 A 21-2360 A
21-2350 B 21-2080 B 21-2360 B
Type 2K PUR 2K PUR 2K PUR
Mixing ratio A: B [parts by weight] 100: 16 100: 10 100: 15
Mixed viscosity [mPa * s] DIN 53019 2.500 ± 200 4.400 ± 200 2.800 ± 200
Effective use time 20 ° C [min] 45 13 38
Density [g / cm3] ISO 1183 1.52 ± 0.01 1.61 ± 0.01 1.68 ± 0.01
Hardness [Shore] 20 ° C ISO 868 D 48 A 82 D 71
Glass transition temperature Tg [° C] ISO 11357 10 -35 10
Operating temperature range [° C] -40 to 130 -40 to 130 -40 to 130
Thermal conductivity [W / mK] DIN EN 993-
14 / 993-15 0.84 0.95 1.09
Dielectric strength [kV / mm] 29 22 29
Fire resistance UL94 V0 / 3mm
File 111148 V0 / 1.5 mm File 111148 V0 / 1.5mm
File 111148
At present, Rampf materials are getting more and more applications in the field of electric vehicles. With its consistent attitude, Rampo is making every effort to meet the needs of customers and the requirements of technological progress.