Ultra-Low Content Triethylammonium Chloride Facilitates Localized High-Concentration Electrolytes and Formation of Inorganic Solid Electrolyte Interface

Authored by

Zhihua Lin, Frederik Bettels, Taoran Li, Sreeja K. Satheesh, Haiwei Wu, Fei Ding, Chaofeng Zhang, Yuping Liu, Hui Ying Yang, Lin Zhang

Abstract

Localized high-concentration electrolytes offer a potential solution for achieving uniform lithium deposition and a stable solid-electrolyte interface in Lithium metal batteries. However, the use of highly concentrated salts or structure-loaded diluents can result in significantly higher production costs and increased environmental burdens. Herein, a novel localized high-concentration electrolyte is developed, comprising ultra-low content (2% by mass) triethylammonium chloride as an electrolyte additive. The stable Lewis acid structure of the triethylammonium chloride molecule allows for the adsorption of numerous solvent molecules and TFSI⁻ anions, intensifying the electrostatic interactions between lithium ions and anions. The chloride ions introduced by TC, along with TFSI⁻ anions, integrate into the solvent sheath, forming a LiCl-rich inorganic SEI and enhancing the electrochemical performance of the lithium metal anode. The improved Li||Li cell shows excellent cycling stability for over 500 h at 1 mA cm² with a 27 mV overpotential. This work provides insights into the impact of electrolyte additives on the electrode-electrolyte interface and Li-ion solvation, crucial for safer lithium metal battery development.

Details

Organisation(s): Institute of Solid State Physics
External Organisation(s): Shaanxi University of Science and Technology
Anhui University
Chinese Academy of Sciences (CAS)
Chongqing Institute of Green and Intelligent Technology
Singapore University of Technology and Design
Type: Article
Journal: Energy and Environmental Materials
Volume: 8
ISSN: 2575-0348
Publication date: 04.08.2025
Publication status: Published
Peer reviewed: Yes
ASJC Scopus subject areas: Renewable Energy, Sustainability and the Environment, General Materials Science, Water Science and Technology, Environmental Science (miscellaneous), Waste Management and Disposal, Energy (miscellaneous)
Sustainable Development Goals: SDG 7 - Affordable and Clean Energy
Electronic version(s): https://doi.org/10.1002/eem2.70029 (Access: Open )