Fast Li+ De-Solvation Kinetics with PDDA Intercalated-Montmorillonite Hybrid Artificial Interface Layer on Cu Substrate for Lithium Metal Batteries in a Wide Climate Temperature

Abstract

The tolerance requirement of lithium metal batteries in harsh environments presents great challenges to electrode materials and electrolytes because temperature plays a significant effect in electrochemical processes. In this study, a new artificial layer on a copper current collector that boosts the de-solvation kinetics and provides electrostatic shielding effects is presented to enhance the electrochemical performance of lithium metal batteries. This new artificial layer is constructed with poly(diallyl dimethyl ammonium chloride) (PDDA) and exfoliated montmorillonite (MMT) nanosheets, which combine the advantages of both inorganic clay and organic polymer. Within this protective hybrid layer, the PDDA cations increase the interlayer spacing of MMT, broadening the diffusion pathways of Li⁺ and accelerating their fast diffusion. Moreover, the PDDA-MMT protective layer facilitates Li⁺ de-solvation at the interface of the Li anode and electrolyte, enabling the rapid and reversible plating/stripping of lithium metal. As a result, the as-prepared PDDA-MMT@Cu anode exhibits excellent stability, and good rate performance is achieved in a commercial electrolyte in the temperature range of −20–60 °C. By combining enhanced diffusion kinetics and electrostatic shielding as an artificial protective layer, this clay-polymer composite provides a synergistic interaction and offers new inspiration for the development of lithium metal batteries.