Hybrid quantum-classical model of mechano-electrochemical effects on graphite-electrolyte interfaces in metal-ion batteries

Electrochemical double layer (EDL) in rechargeable metal-ion batteries is important to ion intercalation and deintercalation (IID) reactions. Mechanical factors of metal-ion batteries shape the local reaction condition in the EDL and further influence the kinetics of IID reactions. This so-called mechano-electrochemical (MEC) effects on IID reactions are treated in this work based on a hybrid quantum–classical (HQC) framework that accounts for the coupling of ion and electron transfer, EDL structure, and mechanical factors. Under well-defined approximations, an analytical expression for the activation energy of IID reactions is obtained, where the MEC effects are explicitly expressed. In particular, a mechano-electrostatic coupling coefficient is defined to describe how the mechanical deformation and structural size influence the IID reactions via changing the local reaction condition in the EDL. The present work represents a step towards microscopic understanding of the MEC effects on the kinetics of IID reactions in rechargeable metal-ion batteries.