Computational Study on the Effects of Mechanical Constraint on the Performance of Si Nanosheets as Anode Materials for Lithium-Ion Batteries

Abstract

Lithiation process of Si has been widely studied, while most of the previous works neglected the effects of mechanical constraint from the accessory materials such as binder and conductive additive on Si. In this paper, we carry out molecular dynamics simulations to investigate the effects of mechanical constraint on the performances, such as capacity and lithiation rate, of Si nanosheets as the anode material for lithium-ion batteries. Our results show that strong mechanical constraint would largely affect the capacity and lithiation rate of Si nanosheets. Remedial strategies for improving the capacity and lithiation rate of the constrained Si nanosheets are proposed, giving rise to guidelines for the design of Si-based anode material for high-performance lithium-ion batteries.