Mussel-Inspired Coating and Adhesion for Rechargeable Batteries: A Review.

A significant effort is currently being invested to improve the electrochemical performance of classical lithium-ion batteries (LIBs) or to accelerate the advent of new chemistry-based post-LIBs. Regardless of the governing chemistry associated with charge storage, stable electrode-electrolyte interface and wet-adhesion among the electrode particles are universally desired for rechargeable batteries adopting liquid electrolytes. In this regard, recent studies have witnessed the usefulness of mussel-inspired polydopamine or catechol functional group in modifying the key battery components, such as active material, separator, and binder. In particular, the uniform conformal coating capability of polydopamine protects active materials from unwanted side reactions with electrolytes and increases the wettability of separators with electrolytes, both of which significantly contribute to the improvement of key battery properties. The wet-adhesion originating from catechol functional groups also largely increases the cycle lives of emerging high-capacity electrodes accompanied by huge volume expansion. This review summarizes the representative examples of mussel-inspired approaches in rechargeable batteries and offers central design principles of relevant coating and adhesion processes.