Recoverable aggregate-rich liquefied gas electrolytes for enabling high-voltage lithium metal batteries

Abstract

High-energy density, improved safety, temperature resilience, and sustainability are desirable yet rarely simultaneously achieved properties in lithium-battery electrolytes. In this work, we present an aggregate-rich electrolyte that leverages the complementary features of ionic liquids and liquefied gas solvents, achieving a high conductivity of 17.7 mS cm⁻¹ at room temperature. The aggregate-rich solvation chemistry and enhanced fluidity result in superior performance of 20 μm Li/NMC811 full cell batteries with 90.41% capacity retention at 4.4 V, 80% capacity retention after 150 cycles, and enhanced low-temperature compatibility until −60 °C. Additionally, we demonstrate a conceptual workflow for recovering individual electrolyte components, contributing to the circularity of batteries. This work provides a pathway to sustainable, temperature-resilient high-voltage (>4.4 V) lithium–metal batteries that maintain state-of-the-art electrochemical performance, potentially advancing the development of next-generation energy storage systems.