Reversible Low Temperature Li‐Storage in Liquid Metal Based Anodes via a Co‐Solvent Strategy†. Issue 10 (6th August 2021)

• Record Type: Journal Article
• Authors: Zhang, Mengdi; Lei, Xiaofeng; Lv, Yang; Liu, Xizheng; Ding, Yi
• Is Part Of: Chinese journal of chemistry. Volume 39:Issue 10(2021)
• Page Start: 2801
• Page End: 2807
• Publication Date: 2021-08-06
• Subjects: Methyl butyrate -- Solvent effects -- Alloys -- Low temperature -- Lithium; Chemistry -- Periodicals; 540.5
• DOI: 10.1002/cjoc.202100309
• Languages: English
• ISSNs: 1001-604X

Abstract

Main observation and conclusion: The application of lithium‐ion batteries in cold climates has been hindered due to the decline in performance at low temperatures. The increased de‐solvation energy and formation of Li dendrites at the anode surface emerge as the major challenges, which rely on the development of stable anode and compatible electrolytes. Herein, a self‐healing GaInSn liquid metal (LM) based electrode coupled with a multi‐solvent electrolyte is proposed toward reversible Li‐storage at low temperatures. By using methyl butyrate (MB) as a co‐solvent in 1 mol·L –1 LiTFSI of ethylene carbonate and diethyl carbonate, the electrolyte viscosity decreases from 52.07 to 13.75 mPa·s, while the ionic conductivity increases from 1.38 to 3.44 mS·cm –1 at –20 °C. Moreover, the Li/MXene@LM cells can display a discharge capacity of 500 mAh·g –1, with capacity retention of 78% at –20 °C after 120 cycles. It is disclosed that a uniform LiF‐rich solid electrolyte interface (SEI) layer on the anode is formed upon the addition of MB, which promotes the desolvation of Li ions at the interface of electrode/electrolyte especially at low temperatures. These results prove that MB as the co‐solvent is well compatible with LM based anodes and holds great potential for the exploration of low‐temperature energy devices. Abstract : Self‐healing liquid metal based anodes with methyl butyrate co‐solvent electrolyte are developed for lithium ion batteries and their Li‐storage performance can be evidently improved especially at low temperatures.