Progress in Electrolyte Design for Ultrahigh Energy Density Lithium Metal Batteries

Abstract

Abstract: Ultrahigh energy density (>500 Wh/kg) lithium metal batteries represent a critical battery technology to achieve practical applications such as long-range electric vehicles and low-altitude economy. However, issues like lithium dendrite growth and parasitic decomposition at high-voltage cathode interface severely limit their practical applications. Current commercial electrolytes struggle to meet the extreme requirements of ultrahigh energy density lithium metal batteries. Therefore, there is an urgent need to develop novel electrolytes featuring high interface stability, the ability to regulate uniform lithium plating/stripping, and fast ion transport. This review firstly outlines the fundamental principles for designing lithium metal batteries with energy density of >500 Wh/kg. Based on this foundation, this review systematically summarizes the recent design concepts for novel electrolytes in ultrahigh energy density lithium metal batteries, including the design of lithium salts, solvents, and additives for conventional concentration electrolytes, lithium salts, main solvents, and diluents for localized high-concentration electrolytes, weakly solvating electrolytes, and quasi-solid electrolytes. Furthermore, this review emphasizes the requirement for interfacial stability at extremely low electrolyte volume in ultrahigh energy density lithium metal batteries, providing theoretical guidance for future novel electrolyte design. Finally, this review summarizes the advantages and disadvantages of existing electrolyte design strategies and outlines future research directions, including molecular structure design of electrolyte components, cathode/electrolyte matching, high-rate charging/discharging capability, advanced characterization techniques, and safety issues of batteries.

Key words: electrolyte, lithium metal batteries, high energy density, electrode/electrolyte interface

CLC Number:

TM911

ZHANG Jiaming, SHI Boyang, LIN Weiqi, XIA Jiahao, HE Tong, YI Yong, LI Yong, ZHANG Qiaobao. Progress in Electrolyte Design for Ultrahigh Energy Density Lithium Metal Batteries[J]. Energy Storage Science and Technology.

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