Volume 63

Influence of Global Mechanical Loading on Spatially Lithium Plating in Wound Lithium-Ion Batteries Ruohan Sun, Ying Chen, Haofeng Chen, Weiling Luan

Abstract

Lithium-ion batteries inevitably experience global mechanical loading during service, which significantly affects the electrode-separator interfacial contact, leading to spatial heterogeneity in current density and reaction overpotential. These effects can promote localized onset of lithium plating at the graphite anode, especially under low-temperature conditions. Lithium plating not only accelerates capacity fade and shortens cycle life, but the resultant dendrites may also pierce the separator, causing internal short circuits and potential safety hazards. In this work, using a wound NCM811/graphite pouch cell as a representative case, we combine numerical simulation with experimental characterization to systematically investigate the spatial heterogeneity of lithium plating on the graphite anode across different levels of global mechanical loading. The results reveal that global mechanical load preferentially compacts the wound region, significantly reducing separator porosity and electrolyte transport capability, thereby increasing ionic resistance and diffusion limitation. These findings elucidate the mechanical–electrochemical mechanisms governing lithium plating and provide a theoretical basis for optimizing cell structural design, stack-pressure strategies and the prevention of lithium-plating-induced safety risks in lithium-ion batteries.

Keywords Lithium-ion batteries, lithium plating, mechanical load