Abstract: The finite element analysis of the connection structure between the liquid cooled battery box and the guide rail in the energy storage battery cabin under ocean transportation conditions was carried out based on Workbench software. The weak links in the structural design were identified. Simultaneously the strengthened design and strength verification were carried out. Firstly, the extreme conditions were determined based on data analysis during ocean transportation. And the finite element analysis on this connecting structure was carried out under extreme conditions based on the Workbench software. Thus, the weak links were identified where the strength does not meet design requirements. Based on the issue of insufficient strength, a rectangular tube array reinforcement structure was designed and installed in the gap between the liquid cooled battery box and the door frame to restrict the liquid cooled battery box from moving towards the outside of the battery cabin. Finally, the finite element analysis and strength verification were conducted on the strengthened model, and the simulation results showed that the strength of the strengthened model under the extreme conditions of ocean transportation met the design requirements, thereby ensuring the safety and reliability of the battery cabin during ocean transportation. This study provides an analytical method and reference basis for the structural design and strength evaluation of battery cabin during ocean transportation in the future.