Charge Delocalization Electrolyte Design to Construct Fast Dynamic Interface for High‐Voltage Lithium Metal Batteries

ABSTRACT Lithium metal batteries are considered the most promising candidates for next‐generation energy storage devices due to their high‐energy density. To unleash the potential of lithium metal batteries, they are typically paired with oxide cathodes that can operate at high voltages. However, under high‐voltage conditions, the structural collapse of oxide cathodes and the crossover effect of transition metal ions not only cause damage to the cathode structure, but also impair the interface stability of lithium metal anodes. Herein, a design strategy for charge delocalization effect solvents was proposed in this work, which breaks through the limitations of traditional performance optimization strategies for high‐voltage lithium metal batteries. This charge delocalization electrolyte system can effectively construct a fast dynamic interface. The Li||NCM811 battery assembled with this electrolyte system exhibits 72.64% (N/p = 1.5) capacity retention after 400 cycles at a high‐voltage of 4.6 V, which is a high level in high‐voltage electrolytes. Even with a high mass loading of 18.4 mg cm −2 , the battery also reaches capacity retention of 86.33% after 70 cycles. This research result lays the foundation for the development of high‐voltage lithium metal batteries.