Revisiting Lithium Metal Battery Failure from a Corrosion Science Perspective

The pursuit of practical high–energy–density lithium (Li) metal batteries faces a fundamental challenge, that is, limited cycle life resulting from structural and interfacial instability caused by material degradation (e.g., inactive Li). These failure mechanisms originate from the corrosion of Li metal anodes (LMAs), high–voltage cathodes, and inactive battery components, which begin at material interfaces and spread across the electrode structure. On the basis of industrial corrosion frameworks, this review analyzes battery corrosion classified by chemical and electrochemical patterns, which promote the understanding of active and inactive material degradation. The failure mechanisms across different battery components are systematically examined. Recent progress on underlying mechanisms, key challenges, and corrosion–focused design strategies has been discussed, indicating the significance of LMA stabilization and dynamic interface control. Advanced characterization tools for uncovering the corrosion behaviors have been analyzed. Integrating the recognition of battery corrosion with machine learning and feature engineering allows for revealing the realistic corrosion inhibition mechanisms and achieving real–time battery life prediction. Finally, we present fresh perspectives and potential solutions to mitigate corrosion–induced failure in critical battery components, aiming to inspire transformative developments in next–generation high–energy–density Li metal batteries.