Mechanical Characterization of Carbon/Glass Fiber Hybrid Composites for Honeycomb-Structured Battery Enclosures

In this study, to optimize the lightweight design of power battery cases for new energy vehicles and meet impact resistance requirements, the mechanical properties of honeycomb sandwich composites were experimentally investigated by varying carbon/glass fiber hybrid ratios. Carbon fiber and glass fiber hybrid laminates were used as the panel, and the aluminum honeycomb was used as the core layer to prepare sandwich composite materials through vacuum-assisted resin infusion (VARI). Then, the flexural and impact properties of honeycomb sandwich composites with different hybrid ratios were tested, respectively. The damage morphology and the damage mechanism of the hybrid composites were analyzed by 3D profile scanning. The results demonstrated that compared to glass fiber-reinforced panels, hybrid panels significantly enhanced the flexural load-bearing capacity of the sandwich composites, exhibiting maximum increases of 26.5% and 34.38% in the L direction and W direction, respectively. Carbon fiber effectively improved the impact resistance of specimens, with the maximum impact load increasing by 53.09% and energy absorption showing measurable enhancement, while glass fiber improves toughness and reduces the severity of damage. This study includes damage analysis and mechanical behavior change analysis of composite materials, which can provide a reference for the application of composite materials in the battery box shell.