Influence of Positional Isomerism in Weakly Solvating Ethers on Lithium Metal Deposition
Abstract
ABSTRACT Lithium metal is a promising anode for next‐generation high‐energy batteries but faces issues like internal short circuits and low Coulombic efficiency (CE), limiting its performance. Although factors like solid‐electrolyte interphase (SEI) composition, charge transfer resistance, solvation structure, and solvent symmetry influence Li metal deposition, a unified descriptor remains absent. Here, we systematically investigate three positional isomers of weakly solvating ether solvents—dipropyl ether (DPE), butyl ethyl ether (BEE), and pentyl methyl ether (PME), selected to maintain the same C/O (carbon/oxygen) ratio of 6, allowing isolation of minor structural variations on Li metal deposition. By correlating charge transfer kinetics, solvation structure, SEI composition, and lithium microstructure with electrochemical performance, we identify key factors influencing deposition. The symmetric ether, DPE, with sluggish charge transfer kinetics and the most pronounced ion pairing, achieved the highest CE of 99.26%, followed by BEE (99.24%) and PME (98.89%). Increased ion pairing and enhanced LiF content in the SEI were found to have the strongest linear correlation with interfacial stability as reflected in CE. These findings challenge previous studies that faster charge transfer kinetics led to improved CE and enhance the understanding of designing weakly solvating ethers with optimized oxygen placement for future Li metal batteries.
Article Details
Authors (15)
Ishita Das
Research Institute for Sustainable Energy The Chatterjee Group Centre's for Research and Education in Science and Technology (TCG‐CREST) Kolkata India
Md. Arif Faisal
Department of Chemistry Purdue University West Lafayette Indiana USA
Ashutosh Rana
Department of Chemistry Purdue University West Lafayette Indiana USA
Soumita Chakraborty
National Graphene Institute (NGI) & Department of Chemical Engineering (DCE) University of Manchester Manchester UK
Debopam Pal
Department of Chemical Sciences Indian Institute of Science Education and Research Kolkata, Mohanpur Campus Kalyani West Bengal India
Brajesh Rajesh Bhagat
Research Institute for Sustainable Energy The Chatterjee Group Centre's for Research and Education in Science and Technology (TCG‐CREST) Kolkata India
Navneet Singh
Department of Chemistry, Indian Institute of Technology Delhi 1 , Hauz Khas, New Delhi 110016,
Soumen Sensarma
TCG Life Sciences Pvt. Ltd. Kolkata India
Purnendu Kumar Roy Chowdhury
TCG Life Sciences Pvt. Ltd. Kolkata India
Bidisa Das
Research Institute for Sustainable Energy The Chatterjee Group Centre's for Research and Education in Science and Technology (TCG‐CREST) Kolkata India
Alakesh Bisai
Hemant K. Kashyap
Department of Chemistry, Indian Institute of Technology Delhi 1 , Hauz Khas, New Delhi 110016,
Jeffrey E. Dick
Department of Chemistry
Ambar Banerjee
Research Institute for Sustainable Energy (RISE)
Abhik Banerjee
Research Institute for Sustainable Energy, The Chatterjee Group Centre’s for Research and Education in Science and Technology (TCG-CREST)