High‐Entropy Electrolytes: Advancing Low‐Temperature Lithium Batteries Toward Extreme Environments

With the growing demand for lithium batteries in extreme environments such as high‐latitude and high‐altitude regions, their reliable operation has become increasingly important. The electrolyte, as a key component of batteries, plays a critical role in determining overall battery performance. Under low‐temperature conditions, electrolyte failure has become a major bottleneck limiting the practical operation of batteries. Conventional low‐temperature electrolyte design strategies mainly rely on solvent‐system optimization, regulation of the solid electrolyte interphase (SEI), and the construction of localized high‐concentration electrolytes. However, these approaches still struggle to fully overcome key low‐temperature challenges, including reduced ionic conductivity, sluggish Li ⁺ desolvation kinetics, and SEI degradation. In recent years, the high‐entropy strategy has emerged as an effective multicomponent approach for optimizing low‐temperature electrolytes. This review systematically summarizes the application of the high‐entropy strategy in liquid, inorganic solid, and solid polymer electrolyte systems, with particular emphasis on its role in regulating solvation structures, low‐temperature fluidity, ionic conductivity, SEI formation, and low‐temperature electrochemical performance. It is expected that this work will provide useful insights into the rational design of advanced high‐entropy electrolytes for lithium batteries operating at low temperatures.