(Invited) Understanding the Coupled Electrochemical-Mechanical Behavior of Materials for Improving the Performance and Durability of Lithium-Ion Batteries

Abstract

With an increasing demand for higher energy and power density of lithium-ion batteries (LIBs), the coupled electrochemical-mechanical degradation of electrode materials becomes a more pressing problem. In particular, fracture and delamination of electrodes can occur during repeated charging and discharging of LIBs. An improved understanding of the mechanical behavior of electrode materials, which often evolves with the state-of-charge and cycle number, is therefore necessary for improving the performance and durability of LIBs and other types of batteries. In this presentation, I will provide an overview of our recent work on using four complementary measurement techniques: (1) electrochemical nanoindentation, (2) scanning probe microscopy, (3) peel adhesion and cohesion test, and (4) electrode curvature measurement to help understand several coupled effects between mechanical and electrochemical behavior of materials on the performance and durability of high capacity electrodes. Examples include silicon/polymer porous composite electrodes, polymeric binders, lithium metal electrodes, and ceramic materials for the positive electrode and solid-state electrolyte. These characterization techniques may also be used to investigate the coupled electrochemical-mechanical behavior of a wide range of materials for lithium-ion batteries and beyond.