氟化高浓电解液实现无水氟化铜正极的可逆循环  

Enabling the reversibility of anhydrous copper(II)fluoride cathodes for rechargeable lithium batteries via fluorinated high-concentration electrolytes

作　　者：戴一铭 刘旭阳 伍旺炎 黄瑛 王腾锐 宋振友 张任远 罗巍 Yiming Dai;Xuyang Liu;Wangyan Wu;Ying Huang;Tengrui Wang;Zhenyou Song;Renyuan Zhang;Wei Luo(Institute of New Energy for Vehicles,School of Materials Science and Engineering,Tongji University,Shanghai 201804,China;Institute of Carbon Neutrality,Tongji University,Shanghai 200092,China)

机构地区：[1]Institute of New Energy for Vehicles,School of Materials Science and Engineering,Tongji University,Shanghai 201804,China [2]Institute of Carbon Neutrality,Tongji University,Shanghai 200092,China

出　　处：《Science China Materials》2023年第8期3039-3045,共7页中国科学（材料科学（英文版）

基　　金：This work was supported by the Fundamental Research Funds for the Central Universities and the Institute of Carbon Neutrality of Tongji University.

摘　　要：无水氟化铜(CuF_(2))有望成为下一代锂电池正极材料,其高比容量(528 mA h g^(−1))和高工作电压(3.55 V vs.Li/Li^(+))使得其能量密度高达1874 W h kg^(−1).然而,由于充电时铜的溶解,CuF_(2)正极容易失活,这限制了其发展.本研究采用氟化高浓电解液抑制铜的溶解,从而实现了CuF_(2)正极的可逆循环.采用氟化高浓电解液后,CuF_(2)正极的容量在30次循环后仍保有228 mA h g^(−1),是使用传统碳酸酯类电解液的电池容量的近三倍.综上,本研究提出了一种电解质工程策略,可以实现CuF_(2)正极的可逆充放电.Anhydrous copper(II)fluoride(CuF_(2))has a high specific capacity of 528 mA h g^(−1)with an operating voltage of 3.55 V vs.Li/Li^(+),achieving a high gravimetric energy density of 1874 W h kg^(−1),which makes it a promising cathode candidate for next-generation rechargeable lithium(Li)batteries.However,the notorious dissolution of Cu during charging triggers the rapid failure of the CuF_(2)cathode,impeding its development.In this work,the reversibility of the anhydrous CuF_(2)electrode was enabled via the use of a fluorinated highconcentration(FHC)electrolyte to effectively suppress the dissolution of Cu.With the FHC electrolyte,the CuF_(2)–Ketjen Black nanocomposite cathode delivered a reversible capacity of 228 mA h g^(−1)after 30 cycles,which nearly tripled that of the baseline electrolyte.Thus,the strategy of electrolyte engineering is proposed to harness CuF_(2)as a high-capacity cathode material for Li batteries.

关 键 词：锂电池正极材料 电池容量 可逆循环 电解液 高比容量 能量密度 工作电压 碳酸酯 

分 类 号：TM912[电气工程—电力电子与电力传动] O646.1[理学—物理化学]