In order to improve the performance, life and reduce the cost of Proton Exchange Membrane Fuel Cell (PEMFC), the key materials and technological progress of Membrane Electrode Assembly (MEA) are reviewed. Results show that the catalyst layer reaction efficiency and mass transfer capacity can be improved effectively by using mesoporous carbon support, high activity low platinum catalyst, high oxygen permeability ionomer and optimized three-phase interface structure; the development of thin and high temperature Proton Exchange Membrane (PEM) can reduce ohmic loss and broaden the operating temperature window; the thin and integrated Gas Diffusion Layer (GDL) is designed to enhance the reaction gas transport and water management. While these material technologies show promise in advancing fuel cells toward low-platinum, high-performance, and long-life, they still face problems such as low durability, high cost, and lack of large-scale production. Future research should focus on material innovation, structural optimization, and process breakthroughs to accelerate the commercialization of fuel cells.

As a core component of high-temperature proton exchange membrane fuel cells, membrane materials determine the commercial viability of hydrogen energy in the commercial vehicle sector, particularly in terms of their high-temperature stability, adaptability under dynamic operating conditions, and cost. Therefore, this paper reviews the technological evolution of high-temperature proton exchange membranes from laboratory research to automotive engineering applications. The performance characteristics and degradation mechanisms of perfluorinated composite membranes, phosphoric acid-doped polybenzimidazole membranes, and novel composite membranes under typical commercial vehicle operating conditions are analyzed. The compatibility bottlenecks between membrane materials and fuel cell systems are examined, along with optimization pathways for better integration. Solutions are proposed from three dimensions: material structural design, preparation process innovation, and system integration synergy. Future development directions, such as digital monitoring and green low-carbon manufacturing, are also discussed.

Traditional CAE modeling of door structures typically employs uniform wall thickness properties, failing to account for thickness variations after sheet metal forming. Therefore, it is of practical significance to develop a structural CAE model that incorporates the non-uniform wall thickness resulting from the forming process of door inner and outer panels. This paper investigates a method for constructing a structural CAE model of aluminum alloy door panels with non-uniform thickness based on forming analysis. In this model, the wall thickness properties of the inner and outer panels are assigned the non-uniform thickness values obtained from formability CAE analysis. A comparative analysis is conducted between the calculated stiffness and experimental stiffness of the aluminum alloy door panels using both uniform and non-uniform wall thickness CAE models. The results show that, compared to the uniform thickness CAE model, the structural CAE model based on forming-induced non-uniform thickness significantly improves the accuracy of door stiffness predictions. Specifically, the accuracy of torsional stiffness calculations at the upper corner point increases by 10.6%, at the lower corner point by 6.3%, at the outer waistline by 5.2%, at the inner waistline by 5.5%, at the upper mounting point of the window regulator by 7.7%, and at the lower mounting point of the window regulator by 7.5%.

To optimize the thermal shrink fitting process of the stator core and housing in new energy electric drive systems and improve the qualification rate of thermal shrink fitting, a systematic study is conducted on key issues such as heating temperature, assembly accuracy, heating uniformity, and core rebound in the process. The results show that after housing heating, changes in the positioning hole spacing due to "thermal-structural coupling" led to axis offset, and a diamond pin positioning compensation scheme is proposed. By optimizing the heating process and Proportional-Integral-Derivative (PID) control, heating uniformity is improved. The stress-strength interference model is applied to verify the reliability of the assembly gap. In response to core rebound, the dwell time is optimized, and spray cooling is introduced, effectively enhancing cooling efficiency and dimensional stability. Practice has shown that the related measures significantly improve the qualification rate and production efficiency of the assembly process.

With the expansion of commercial vehicles in both domestic and international markets, the quality problem of threaded fastener loosening has become increasingly prominent due to changes in their operating conditions. Focusing on the common loosening forms of threaded fasteners in commercial vehicles, this paper analyzes the loosening principles and influencing factors, and puts forward corresponding optimization suggestions and measures, so as to provide solutions for the anti-loosening design of threaded fastener connections and the treatment of loosening-related quality problems in commercial vehicles.

To investigate the properties of laser spiral spot welded joints of galvanized steel sheets with different spiral trajectory diameters, experiments were carried out on two lap joint configurations: a 0.7 mm and 2.5 mm large thickness ratio lap joint of galvanized steel sheets, and a three-layer thin galvanized steel sheet assembly with a thickness of 0.7 mm. For each configuration, three groups of tests were designed, including resistance spot welding and laser spiral spot welding with spiral trajectory diameters of 6 mm and 8 mm, respectively. After welding, the welded joints were analyzed from the perspectives of macro-appearance, metallographic microstructure and shear mechanical properties, so as to study the differences of laser spiral spot welded joints under different spiral diameters. The results show that the surface quality of laser spiral spot welded joints is relatively poor, and there is no significant difference in the surface quality of laser spot welded joints with different spiral trajectory diameters. However, the shear resistance and energy absorption capacity of the welded joints are significantly enhanced with the increase of laser spiral trajectory diameter, which proves that the spiral trajectory diameter has a great influence on the mechanical properties of the welded joints. Compared with resistance spot welding, laser spiral spot welding is superior in plastic deformation capacity and energy absorption performance.

To improve the first pass yield rate of polish line in an automobile paint shop, this paper focuses on the critical top coat defects such as crater, other paint, paint runner, solvent spot and paint sludge. The research diagnoses the root causes of various defects systematically through Manufacturing Report System (MRS) quality analysis system and "human, machine, material, methodology, environment" real reason analysis method combining infrared spectrum, element analysis and production verification. There are some targeted countermeasures to solve the defect issues such as changing the fluorine-containing lubricating grease of high temperature zone, optimizing top coat color sequence, strengthen equipment pre-maintenance, adjusting process parameter and changing fault part. The first pass yield of polish line increases from 79% to 91% and the average daily line downtime is reduced by 62% due to the countermeasures implementation. The research shows that systemtic root cause analysis and precise process impoovements are the key to enhancing coating quality and production efficiency.

In this study, the modified HA1-H materials are studied by adding different contents of Fe and other impurity alloys. Through the targeted design of components and processes, the mechanical properties, microstructure and corrosion properties of the produced test plates are experimentally analyzed. Based on the 0.5% Fe material characteristics and product design structure, the fluid state and solidification simulation of the rear floor of a model of ZEEKR are carried out, and the production and analysis are carried out in combination with the design process. Research shows that heat-free high-pressure die-casting aluminum alloy with 0.5% Fe element content can meet the performance requirements of automotive rear floor products.

Driven by the rapid iteration of New Energy Vehicle (NEV) technologies, significant changes in thermal management operating conditions of NEVS, Which has promoted innovations in the materials and structures of cooling hoses. Based on the background of the automotive industry's transition to new energy solutions, this paper first systematically analyzes the core application requirements for automotive cooling hoses across 3 dimensions: performance, cost, and lightweight. Subsequently, it comprehensively reviews 4 categories of typical cooling hose technological solutions currently in mainstream application or under development. Finally, it provides a prospective outlook on the development trend of cooling hose technology for new energy vehicles.

To address the requirements for flexible transportation and precise assembly of multi-size battery packs of new energy vehicles during the final assembly process, a flexible transfer solution for battery packs based on a double-layer roller bed conveyor system has been researched and developed. This solution adopts a skid design with adjustable limiting blocks, and combines a T-type transfer machine, automated guided vehicles, and an overhead buffer system to establish a full-process conveying system covering battery pack loading, buffering, offline assembly, and empty skid return. By integrating Radio Frequency Identification technology and a Manufacturing Execution System through a PLC control system, accurate synchronization between battery pack information tracking and production queues is achieved. Implementation results show that the system can realize overhead buffering of 40 battery packs, improve the workshop space utilization rate by more than 30%, and achieve a battery pack loading accuracy rate of 99.5%. It can ensure continuous supply for 40 min under a production rhythm of 60 JPH (Jobs Per Hour). This conveying solution provides effective technical support for the mixed-model production of new energy vehicles.