Sodium-ion batteries (SIBs) are emerging as promising alternatives to lithium-ion batteries (LIBs) for automotive applications, highlighting the requirement of fundamental research to understand their components and functioning. In addition, large-format cylindrical cells are currently being explored for SIBs for use in electric vehicles. This study presents a safe and systematic methodology for the forensic analysis of large-format cylindrical SIB cells, focusing on how manufacturing influences their operational behavior and safety. Comprehensive evaluations of cell design and electrode and electrolyte chemistry were performed through advanced microscopic and spectroscopic characterization. Furthermore, three-electrode cells were reconstructed from harvested electrodes to more deeply assess electrochemical performance, including cycle life, efficiency, and rate capability. This reverse-engineering approach establishes a robust foundation for evaluating SIB performance metrics and enables a direct comparison with commercial LIBs. The findings are essential for optimizing SIB design and guiding selection of the most suitable battery chemistry for specific end-user applications.
Nakhanivej et al. (2026) studied this question.