Plastics in Electric Vehicle Charging
The shell of the charging station is divided into 6 parts that can be made of plastic, namely the charging station body, the charging station plug, the charging station socket, the charging gun shell, the circuit breaker, and the contactor and power module shell. Due to the long-term outdoor use of new energy vehicle charging equipment, it is necessary to consider the impact of high voltage safety, anti-freezing and cold resistance, UV resistance, water resistance, and flame retardancy, among other factors. Therefore, different parts of the shell require corresponding material selection requirements, which must not only meet performance requirements but also be economically safe.
Charging station body material: PC/ABS alloy plastic High gloss, good toughness, and good heat resistance.
The charging station body, as the external protective component of the charging station, not only needs to meet the protective requirements against collisions during transportation, installation, and use but also needs to be suitable for complex operating conditions. The material used requires certain mechanical strength, electrical insulation properties, and flame retardancy requirements, while also having excellent weather resistance, low-temperature impact resistance, corrosion resistance, and processability.
It is recommended to use flame retardant, weather-resistant, and low-temperature-resistant modified plastic materials such as PC/ABS alloy materials. It combines the excellent properties of both PC and ABS. On the one hand, it provides ABS with impact resistance, heat resistance, and rigidity for thin-walled products. On the other hand, it can improve melt flowability, improve processability, electroplatability, and appearance.
Charging gun shell material: PC fireproof grade In addition to flame retardancy, electrical insulation, and weather resistance, the charging gun shell and connection system also need to have good rigidity and toughness to avoid damage caused by falling and vehicle pressure while also considering a good appearance. In terms of materials, it is recommended to use halogen-free flame retardant weather-resistant PC and its alloy materials. PC (polycarbonate) is an amorphous, odorless, non-toxic, highly transparent colorless thermoplastic engineering plastic. It is colorless, transparent, heat-resistant, impact-resistant, and has good mechanical properties. It has high refractive index, good processability, high strength and elastic modulus, low molding shrinkage, good dimensional stability, excellent weather resistance, and is harmless to the human body, in line with hygiene and safety standards.
Charging connectors, including sockets and plugs, directly connect with wire adapters, requiring excellent electrical insulation, flame retardancy, and heat resistance. At the same time, to meet the requirements for long-term plugging and unplugging lifespan, materials need to have excellent mechanical properties. It is recommended to choose PET and PA66 series modified plastic materials.
For the shell of the power module and the internal circuit control system, it is suggested to select modified nylon materials with good physical properties, high temperature resistance, stable dimensions and colors, and good laser marking effects. Nylon (polyamide PA) plastics have excellent mechanical properties, such as high strength, good rigidity, excellent wear resistance, self-lubrication, wide temperature range, good electrical insulation performance, arc resistance, good flame retardancy with self-extinguishing properties, good oil resistance, chemical stability, and easy processing.
Internal control system component material: PA or PBT. The internal control system components mainly include the power module, contactor, circuit breaker, and cooling fan. Referring to the material application in commonly used power systems and low-voltage electrical industries, halogen-free flame retardant reinforced PA or PBT materials can be used.
For the cooling fan, it is recommended to use flame retardant reinforced PBT or PPE materials widely used in the IT industry. PBT is a thermoplastic polyester. Compared to other thermoplastic engineering plastics, non-reinforced PBT has better processability and electrical performance. PBT has a low glass transition temperature and can rapidly crystallize at mold temperatures of 50°C, resulting in shorter processing cycles. Polybutylene terephthalate (PBT) is widely used in the electronics, electrical, and automotive industries. Due to its high insulation and temperature resistance, PBT can be used for applications such as flyback transformers in televisions, automotive distribution panels and ignition coils, office equipment housings and bases, various automotive exterior parts, air conditioning fans, electric stove bases, and office equipment housings.
Wire component material: TPU. The cables used in charging stations mainly include power cables and signal control cables. Detailed specifications are provided for the structure, rated voltage, operating temperature, permissible bending radius, and durability of the charging station cables. Polymer materials are primarily used for the inner sheath and outer jacket of the cables, and halogen-free flame retardant TPU can be used for the inner sheath.