Weakly Solvating Molecule‐Enabled Localized High‐Concentration Electrolytes for Ultralow Temperature Batteries with High‐Nickel Cathode/Lithium‐Metal Anode

作者：Wenjie Dou, Yaqin Tang, Xiang Xie, Xinghui Liang, Hao-Zhe Qin, Zhiming Xiao, Yike Liu, Chao-Ping Liang, Xin-Hai Li, Xing Ou · 发表于：Advanced Functional Materials · 年份：2025 · DOI：10.1002/adfm.202517231 · 被引用次数：21

The ultralow temperature performance of lithium metal batteries (LMBs) is fundamentally limited by sluggish ion transport and interfacial instability in conventional electrolytes. To address this challenge, this work proposes a novel localized high‐concentration electrolyte (LHCE) system, which synergistically regulates solvation structures and interfacial chemistry to achieve efficient ion transport and stable electrode/electrolyte interfaces at low temperature. By leveraging weakly solvating solvents 1,2‐diethoxyethane/methyl acetate, the solvation sheath structure is altered in the LHCE, allowing more anions to enter, significantly reducing Li+ de‐solvation activation energy and interfacial resistance. Experimental and simulation results reveal that weakly solvating molecule‐driven anion‐dominated solvation facilitates the formation of inorganic‐rich interphases (LiF/Li3N), effectively suppressing lithium dendrite growth and cathode interface degradation. Therefore, the Li||Cu cell with the designed electrolyte exhibits high lithium plating/stripping coulombic efficiency at −20 °C (>98.8%). Under harsh conditions (4.5 V cutoff, −40 °C), the Li||NCM622 cell maintains 73.4% of the discharge capacity at room temperature and retains 88% of the initial capacity after 400 cycles. This study establishes a novel molecular engineering strategy for electrolyte design, leveraging solvation regulation and targeted interfacial chemistry to unlock high‐performance LMBs.