Improving Lithium Intercalation Kinetics at Nanoconfined Electrochemical Interfaces

Abstract

Improving the performance of lithium-ion batteries (LIBs), as well as establishing alternative cell chemistries such as sodium- or multivalent-ion batteries, requires detailed understanding of ion transport processes across the electrochemical interface and within the solid-state structure of the host electrodes.To enhance the kinetics of the charge storage processes, reducing charge transfer resistance at the interface and/or reducing ion diffusion-limitations in the solid-state are required. This can be achieved, for example, by active material design, electrolyte formulation, or electrode-electrolyte matching.In this contribution, our team’s efforts in improving the kinetics of electrochemical Li+ intercalation reactions are addressed from the electrode material side. Using layered transition metal oxides and two-dimensional transition metal dichalcogenides, we employ an interlayer-functionalization approach with organic pillar molecules to tailor the interlayer micro-environment. Changes in interlayer geometry, realized by organic pillars with different lengths, will cause changes in solid-state Li+ transport properties, with larger interlayer distance favoring Li+ diffusivity. Manipulating interlayer chemical environment is accomplished via organic pillars with different chemical backbone compositions. This can lead to changes in electrode-electrolyte/solvent interaction, impacting the charge transfer resistance. The talk will cover synthesis approaches and (electrochemical) characterization of the systems, highlighting mechanistic insights and pointing out opportunities of interlayer-functionalized materials for ion intercalation applications.