Taming the Temperature Extremes: An Entropy-Regulated Electrolyte for Wide-Temperature Lithium-Ion Batteries

The development of high-energy lithium-ion batteries is crucial for next-generation energy storage and electric vehicle/aircraft technologies; however, their development is hindered by conventional electrolyte designs, which perform poorly across wide temperature ranges. Herein, entropy-enhanced electrolytes have been developed for graphite||LiNi_0.9Co_0.05Mn_0.05O₂ (NCM955) cells by a data-driven approach. Entropy-enhanced electrolytes feature diversified solvation structures that significantly improve thermodynamic stability and ionic kinetics. Furthermore, the film-forming ability of both the anodes and cathodes under various conditions is systematically investigated. One formulation with a moderate entropy value proves particularly effective, facilitating the formation of stable electrode/electrolyte interphases, which enables graphite||NCM955 cells with superior cycling stability across a wide temperature range. Consequently, the as-assembled graphite||NCM955 cells with the entropy-enhanced electrolyte can deliver a remarkable long-term lifespan (>1500 cycles) with a high energy density, maintaining high capacity retention from -30 to 70 °C. This work provides strategic insights for developing next-generation electrolytes for high-energy-density and all-climate-adaptive lithium-ion batteries.