浙江大学范修林团队报道了分子对接电解质可以实现高压锂电池的化学反应。相关研究成果发表在2024年7月15日出版的《自然—化学》。

理想的可充电锂电池电解质应促进电极表面附近的法拉第反应，同时减轻不希望的副反应。然而，由于其高脱溶剂能量和较差的相容性，传统电解质通常表现出缓慢的动力学和严重的降解。

该文中，研究人员提出了一种电解质设计策略，克服了与非配位溶剂中Li盐解离相关的局限性，实现了快速、稳定的Li化学反应。当与氟化苯或卤代烷烃化合物混合时，非配位溶剂通过有利的氢键相互作用被激活，特别是F^δ--H^δ+或H^δ+-O^δ-。这些分子间相互作用实现了动态的Li⁺-溶剂配位过程，从而促进了Li⁺的快速反应动力学并抑制了电极副反应。

利用这种分子对接电解质设计策略，研究人员开发了25种电解质，这些电解质在全电池和袋式电池中都表现出高的锂镀/剥离库仑效率和有前景的容量保持。

该项工作支撑使用分子对接溶剂化机制，为高压锂电池设计具有快速Li⁺动力学的电解质。

附：英文原文

Title: Molecular-docking electrolytes enable high-voltage lithium battery chemistries

Author: Ma, Baochen, Zhang, Haikuo, Li, Ruhong, Zhang, Shuoqing, Chen, Long, Zhou, Tao, Wang, Jinze, Zhang, Ruixin, Ding, Shouhong, Xiao, Xuezhang, Deng, Tao, Chen, Lixin, Fan, Xiulin

Issue&Volume: 2024-07-15

Abstract: Ideal rechargeable lithium battery electrolytes should promote the Faradaic reaction near the electrode surface while mitigating undesired side reactions. Yet, conventional electrolytes usually show sluggish kinetics and severe degradation due to their high desolvation energy and poor compatibility. Here we propose an electrolyte design strategy that overcomes the limitations associated with Li salt dissociation in non-coordinating solvents to enable fast, stable Li chemistries. The non-coordinating solvents are activated through favourable hydrogen bond interactions, specifically Fδ–Hδ+ or Hδ+–Oδ, when blended with fluorinated benzenes or halide alkane compounds. These intermolecular interactions enable a dynamic Li+–solvent coordination process, thereby promoting the fast Li+ reaction kinetics and suppressing electrode side reactions. Utilizing this molecular-docking electrolyte design strategy, we have developed 25 electrolytes that demonstrate high Li plating/stripping Coulombic efficiencies and promising capacity retentions in both full cells and pouch cells. This work supports the use of the molecular-docking solvation mechanism for designing electrolytes with fast Li+ kinetics for high-voltage Li batteries.

DOI: 10.1038/s41557-024-01585-y

Source: https://www.nature.com/articles/s41557-024-01585-y