A path towards high lithium-metal electrode coulombic efficiency based on electrolyte interaction motif descriptor
- Ruhong Li
- Xiaoteng Huang
- Haikuo Zhang
- Jinze Wang
- Yingzhu Fan
- Yiqiang Huang
- Jia Liu
- Ming Yang
- Yuan Yu
- Xuezhang Xiao
- Yuanzhong Tan
- Hao Bin Wu
- Liwu Fan
- Tao Deng
- Lixin Chen
- Yanbin Shen
- Xiulin Fan
2025-05-20
The fundamental interactions and the as-derived microstructures among electrolyte components play a pivotal role in determining the bulk and interfacial properties of the electrolytes. However, the complex structure-property relationships remain elusive, leading to uncontrollable physicochemical characteristics of electrolytes and unsatisfied battery performance. Herein, we propose two interaction motif descriptors to quantify ion-solvent interactions spanning electrostatic to dispersion regimes. These descriptors are highly relevant to salt dissolution, phase miscibility, and electrode-electrolyte interface chemistries. Guided by the principle of minimizing ion-solvent and solvent-solvent interactions while ensuring sufficient salt dissociation, a representative electrolyte, i.e ., lithium bis(fluorosulfonyl)imide dissolved in trimethyl methoxysilane and 1,3,5-trifluorobenzene with a molar ratio of 1:2.5:3.0, is designed, which achieves ~99.7% (±0.2%) Li plating/stripping Coulombic efficiency and endows 4.5 V Li||LiCoO 2 with 90% capacity retention after 600 cycles at 0.2 C/0.5 C charge/discharge rate. Notably, Cu||LiNi 0.5 Co 0.2 Mn 0.3 O 2 pouch cells with this electrolyte sustain over 100 stable cycles. By establishing quantitative relationships between interaction motifs and electrolyte functionalities, this work provides a universal framework for rational electrolyte design, paving the way for highly reversible lithium metal batteries.