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Electrolyte optimization by solvent molecule design has been recognized as an effective approach for stabilizing lithium (Li) metal batteries. However, the coordination pattern of Li+ with solvent molecules has been sparsely considered. Here, we report an electrolyte design strategy based on bi/tridentate chelation of Li+ and solvent to tune the solvation structure. As a proof of concept, a novel solvent with multi oxygen coordination sites is demonstrated to facilitate the formation of an anion-aggregated solvation shell, enhancing the interfacial stability and de-solvation kinetics. As a result, the as-developed electrolyte exhibits ultra-stable cycling over 1400 h in symmetric cells with 50 ?m-thin Li foils. When paired with high-loading LiFePO₄, full cells maintain 92% capacity over 500 cycles and deliver improved electrochemical performances over a wide temperature range from -10 °C to 60 °C. Furthermore, the concept is validated in a pouch cell (570 mAh), achieving a capacity retention of 99.5% after 100 cycles. This brand-new insight on electrolyte engineering provides guidelines for practical high-performance Li metal batteries. This article is protected by copyright. All rights reserved