Efficient manufacturing techniques and connection failure analysis of CFRP lifting lug for main bearing structure

•Integrated molding the web-reinforced foam sandwich composite lifting lug based on thermal expansion molding process technology.•The influence of the web structure on the compression performance and failure mode of the lifting lug samples is analyzed.•Establish the connection scheme of the steel sleeve and clarify the failure mechanism of the steel sleeve under axial compression.•The connection failure model of the lifting lug is established, and the connection performance and failure mode of the steel sleeve are analyzed by the finite element method and test.•The integrated molding of the battery box verifies the engineering value of TEMP technology.