he recent debate over the "copper aluminum" high-voltage wiring harness for new energy vehicles has become a hot topic. Some people believe that this is because car companies have lowered the safety and reliability requirements of vehicles in order to reduce costs, while others believe that using aluminum wire harnesses instead of copper wire harnesses is unacceptable. There are also views that aluminum replacing copper is a technological development trend
We believe that the function of electric vehicle wiring harness is to transmit the electrical energy of the battery pack to various functional components of the vehicle, so that it can work normally, stably and safely, especially the high-voltage wiring harness. It is a key component for realizing the charging and discharging functions of the battery pack, like the main artery of the human body. Its safety and reliability are essential and crucial parts of the overall safety of the vehicle. "Huang Ting, an expert in the new energy vehicle project of the International Copper Industry Association, said in an interview with China Quality News reporters," As a manned transportation vehicle, safety and reliability are all prerequisites, that is, materials with excellent conductivity, stable physical properties and strong environmental tolerance are preferred. Therefore, from the perspective of vehicle safety, copper wire harness should be the first choice for electric vehicles. ''
In Huang Ting's view, the International Copper Association recommends using copper wire as the preferred wiring harness material for electric vehicles, primarily due to the requirements of vehicle safety and reliability. Copper wire is the preferred material for vehicle wiring harnesses. Secondly, from a technical and engineering perspective, the internal conductors of the connectors or electrical connectors currently used in electric vehicles are all copper conductors. If aluminum wire bundles are used, the problem of connecting copper and aluminum materials must be faced. The safety and reliability of this connection are one of the decisive factors for the safety and reliability of wire bundles.
As is well known, the long-term safe and reliable connection of heterogeneous metals such as copper and aluminum is a technical challenge, because copper and aluminum have essential differences in materials themselves. They have different potential differences, which makes these two materials unsuitable for long-term connection. In addition, aluminum is prone to oxidation, and the oxide film formed by it is non-conductive. Huang Ting pointed out that after a certain period of time, the probability of failure increases when copper and aluminum are connected together, especially in complex and harsh vehicle environments such as humidity, vibration, and overlapping high and low temperatures. Once the copper aluminum connection fails, it may cause power outages in the vehicle circuit, which may lead to serious traffic accidents.
Some people may say that using ultrasonic welding and high-grade packaging to ensure that the copper and aluminum joints of the wiring harness are sealed will not cause copper and aluminum joint failures. This measure can indeed improve the connection reliability of copper and aluminum joints to a certain extent, but any packaging cannot guarantee 100% reliability. At the same time, the inspection of wiring harness joints also has problems such as difficulty in daily vehicle maintenance. Therefore, using aluminum wire harnesses for vehicle wiring harnesses reduces the safety and reliability of the vehicle. "Huang Ting said that following the basic principles of electrical safety, electric vehicles should prioritize the use of homogeneous conductor materials when making electrical connections, because the connectors of vehicles are generally copper conductors. Therefore, using copper conductors of the same material for wiring harnesses can avoid this. Reliability issues caused by heterogeneous metal connections. Meanwhile, due to its inherent characteristics of better mechanical properties, tensile strength, and ductility, copper conductors are more suitable for the complex working environment of vehicles. From an engineering perspective, copper is the preferred and preferred material for vehicle wiring harnesses, and is also an important bottom line for protecting vehicle safety.
Cost is a popular term in the debate over the "copper aluminum" high-voltage wiring harness for electric vehicles. Huang Ting also believes that the reasonable reason for "replacing copper with aluminum" may be the balance between vehicle safety and reliability and manufacturing costs made by car companies. The fact that aluminum wire bundles are slightly lighter than copper wire bundles is also a factor to consider, and this practice is called 'compromise' in engineering. However, the safety and reliability of vehicles cannot adopt a 'compromise' strategy. As long as there are multiple solutions that are better, more optimal, and have reasonable costs, the first ranked solution should and must be selected, which is copper wire bundles, "he said.
Making electric vehicles lightweight is an important reason why many car companies choose "aluminum instead of copper" and indicate that this is the trend of industry development. Huang Ting revealed that in order to adapt to the trend of vehicle lightweighting, the International Copper Industry Association is also supporting and collaborating with experts and leading companies in the field of vehicle and wire harness engineering to carry out "potential tapping" work on copper wire harnesses in accordance with the development trend of electric vehicles. At present, they have developed copper wire bundles with cost advantages and similar weight compared to aluminum wire bundles, and are conducting comprehensive testing work in accordance with national standards. I believe this work will provide new momentum for the development of copper wire bundles, and it is also an important task for the copper industry to cooperate with the vehicle and wire harness industries to respond to the development of national new quality productivity, "he finally said.
