The life cycle assessment method was briefly introduced and applied to automotive painting process, the important environmental footprints including carbon footprint during painting production process were tracked, the impact of the use of materials, resources and energy as well as generated emissions on the ecological environment during the whole life cycle production activities of automotive painting process were quantitatively evaluated. The results show that energy consumption and generated emissions, utility power, topcoat and pretreatment electrophoresis processes, and grid power supply have more significant impacts on climate change and fossil resource depletion; material consumption and generated emissions, topcoat, sealant and pretreatment electrophoresis processes, and photovoltaic power supply have more significant impact on ecological toxicity and human toxicity.

In the existing automobile manufacturing process, multi-model and multi-platform co-line production has gradually become a trend. In order to improve the flexibility of the assembly line of automobile chassis system, combined with the characteristics of product structure and the actual situation of production site, the characteristics and requirements of the co-line production of automobile multi-link and torsion beam rear suspension structure were expounded from the aspects of assembly process, equipment form and quality assurance, for the co-line production of the two rear suspension structures were summarized, so as to better adapt to the flexible production needs of automobiles.

The thermal conductivity adhesive, a key component of thermal management of power battery, was taken as the research object, and the simulation model of power battery was established by using simulation software Fluent. The coating area (85%~95%) of the thermal conductivity adhesive was simulated and calculated, and the influence of the use of thermal conductivity adhesive on the temperature field distribution and temperature consistency of power battery under typical working conditions was studied by bench test. It provides the basis for the selection and dosage of thermal conductivity adhesive in the design stage of thermal management scheme. The results show that as the coating area of the thermal conductivity adhesive decreases from 95% to 85%, the maximum temperature of the battery increases from 47.87 ℃ to 50.84 ℃, and the maximum temperature difference of the upper surface increases from 2.40 ℃ to 5.87 ℃. Considering the design criterion of power battery, it is determined that the use of 90% of the coating area of thermal conductivity adhesive can meet the design requirements of the highest temperature and temperature difference under three harsh working conditions of the power battery, avoiding the waste of raw materials caused by excessive heat conductivity adhesive in actual production, and achieving cost savings.

Based on the material consistency and mechanical properties, fracture morphology analysis, structure analysis, stress analysis, failure simulation, broken door handle shell material consistency and mechanical properties met the design requirements, it was found that the parts away from the tip of the modeling of gate structure was prone to stress fracture. Clearance between shell and skeleton was increased from 0.2 mm to 1.2 mm, handle tip comer with rectangular links was changed to bevel and circular arc transition, the position of mold feeding mouth was changed, temperature of the mold was fixed at 50~60 ℃, the drying time of baking material before injection was increased from 1 h to 2 h, the baking stress relief of 80 ℃ for an hour was increased after injection, and the pressure holding time was reduced from 7 s to 4 s, the stress could be reduced which eliminated handle fracture. After the rectification, the parts were verified and tracked, and no similar failure occurred again.

To explore the differences in energy properties between natural gas commercial vehicles and traditional commercial vehicles (diesel), this paper described natural gas characteristics, the cost of refueling equipment, common leakage scenarios, and the emissions of pollutants and greenhouse gases from commercial vehicles, as well as their driving range, then analyzed and explained the gas cylinder and gas route structure and principles of the natural gas commercial vehicle supply system. Arrangement of gas supply system for a domestic heavy-duty commercial vehicle was dissected, and the assembly process and technical specifications for natural gas heavy duty commercial vehicle were developed. Finally, the paper studied the leakage test operation procedures of the GB 19239-2022 “Gas Vehicle Gas System Installation Specifications”, and summarized the nitrogen displacement operation procedures and production processes for natural gas heavy-duty trucks from assembly to storage.

Due to the variety of automotive interior materials, complex composition, and up to hundreds of kinds of odor substances inside each car, odor pollution easily occurs inside the car. In order to improve interior air quality, this study referred to the existing domestic and foreign research on the application of colorimetric technology, proposed an interior odor detection method based on colorimetric sensor array technology, and made colorimetric analysis on the interior materials widely used in the vehicle, accurately identified the odor intensity, odor type and odor pleasure of interior materials samples. In this study, colorimetric sensor array was applied for the first time in the objective characterization of vehicle odor, which can provide data support for odor control in the automobile industry.

To address the issue of full lifecycle management of power battery, this article analyzed the different application scenarios and key functional requirements in the full life cycle management process of power batteries, designed an intelligent battery management system based on the Internet of Things for full life cycle management, and analyzed the operating mechanism of the model. The architecture and functions of the intelligent battery management system were designed, including the system architecture of the terminal battery management system, the selection of key sensors and the functions of cloud based battery management systems. Finally, the characteristics of intelligent battery management systems including compatibility, extendibility and intelligence, as well as the problems they face in application including data security, development and building of cloud based server, were summarized.

In order to address the issue of corrosion in the manufacturing and storage process of die cast aluminum alloy parts without coating on the surface, this article analyzed the corrosion mechanism and cause of die cast aluminum alloy parts, and elaborated on an anti-rust scheme suitable for die cast aluminum alloy, test and application research on anti-rust materials and processes were also carried out. Corresponding rust prevention measures were adopted for each link in the plan, including the use of water-based rust prevention materials and vapor phase rust prevention materials. After laboratory and vehicle verification, this anti-rust technology can effectively prevent corrosion in the manufacturing, storage, transportation, assembly and other processes of die cast aluminum alloy parts, and systematically solve the corrosion problem of die cast aluminum alloy parts.

In the production of a vehicle, the painting shrinkage appeared near the liftgate hinge gasket. This defect occurred frequently and needed to be polished and repaired on site, which greatly affected the production efficiency. The pollutant was determined to be methyl cyclosiloxane by gas chromatography, mass spectrometry and other tests. The cause is that when the silicone rubber gasket is baked in the paint workshop, small molecules of methyl cyclosiloxane are precipitated, which leads to paint pollution. According to this problem, the liftgate hinge gasket was changed from silicone rubber to ethylene propylene diene monomer rubber, which completely solved the problem of paint pollution.

To solve the problem of performance degradation caused by abnormal rotor assembly, this paper analyzed the possible magnetic steel leakage and missing angle fault modes during the assembly process of the rotor assembly. The leakage mode can be prevented through surface magnetic detection, while the missing angle mode cannot be detected and recognized by surface magnetic detection equipment in the industry. Therefore, the paper proposed a method for error prevention and recognition through the analysis of the back electromotive force and vibration characteristic order of the motor, the method can identify the amplitude of higher characteristic order vibration of the motor that exceeding the standard value. In the actual production and manufacturing process, attention is paid to the collection of offline vibration signals of the motor for abnormal operation judgment. After practical verification, this method can effectively identify magnetic steel leakage and missing angle fault modes.