Mini-Review on the Regulation of Electrolyte Solvation Structure for Aqueous Zinc Ion Batteries

Abstract

Zinc as an anode, with low potential (−0.762 V vs. SHE) and high theoretical capacity (820 mAh g−1 or 5854 mAh L−1), shows great promise for energy storage devices. The aqueous zinc ion battery (ZIB) is known as a prospective candidate for large-scale application in the future due to its high safety, environmental friendliness, abundant zinc resources on earth, and low-cost advantages. However, the existence of zinc dendrites and side reactions limit the practical application of ZIBs. Therefore, a lot of effort has been made to improve the performance from aspects including the structure design and surface modification of zinc anodes, regulation of the electrolyte solvation structure, and design of the functional separator. In this review, we attempt to summarize recent advances on the regulation of the electrolyte solvation structure through a number of selected representative works from two aspects: high-concentration salt strategy and electrolyte additives. At the end of this review, the challenges and future development prospects are briefly outlined.

Keywords

• aqueous zinc ion batteries
• electrolyte
• solvation structure
• water in salt