Kinetic Mechanism and Structural Design of Thick Electrodes in Lithium‐Ion Batteries: Challenges and Optimization Strategies

Thick electrode is a critical strategy to increase the energy density of lithium-ion batteries(LiBs) by maximizing the active material loading. However, their practical application is obstructed by kinetic limitations, including low charge transfer efficiency and poor mechanical stability, which severely decrease rate capability, cycling performance, and safety. This review focuses on an intensive analysis of the problems with thick electrodes in terms of ion transfer kinetics, electron transfer discontinuities, and poor mechanical stability. Optimization of charge transfer through vertically aligned and gradient pore structures combined with various electrode micro-modulation techniques, enhancement of electron transfer and interfacial adhesion through the construction of conductive networks and multifunctional adhesives, and further balancing of volumetric energy density and fast charge transfer kinetics through forward fabrication processes such as advanced collector engineering and electrolyte optimization are discussed. In addition, the prospects of electrode microstructures, advanced carbon skeletons, and electrolyte performance are summarized and prospected, which provide new optimization directions for the industrialization of thick electrodes in the future.