Polarizability Engineering of Surface Flattening Molecular Dipoles for Fast and Long Lithium Metal Battery Operation

Abstract

To overcome the energy limitations of conventional Li‐ion batteries (LIB), renewed attention has been given to Li‐metal anodes, which provide the highest capacity and lowest anode potential. To realize Li‐metal batteries (LMBs), it is crucial to stabilize unwanted side reactions on the surface and to inhibit problematic dendrite growth, which causes short‐circuit issues. Herein, diverse pyrrolidone‐based molecular dipole additives controlled by different functional groups are introduced as trifunctional surface stabilizers. It is discovered that the Li–Li symmetric cell improves proportionally with the molar volume and corresponding polarizability values of the molecular dipoles. The highly polarizable pyrrolidone‐based molecular dipoles offer exceptional benefits, including surface flattening of the Li metal anode, controlling the growth direction of crystalline Li, and forming durable solid electrolyte interface (SEI) components. The study is based on polarizability‐controlled molecular dipoles, and offers an effective approach for designing advanced surface stabilizers to develop of high‐performance LMBs.

Keywords

• electrolyte additive
• functional group
• Li‐metal batteries
• polarizability
• pyrrolidone‐based molecules