功能添加剂和保形包覆改性锂金属负极界面  

Anode interface modification of lithium metal batteries:Benefiting from functional additives and conformal coatings

作　　者：李亚婕 郭凯[1] 赵景泰 李驰麟[2,5] Yajie Li;Kai Guo;Jingtai Zhao;Chilin Li(School of Materials Science and Engineering,Shanghai University,Shanghai 200444,China;State Key Laboratory of High Performance Ceramics and Superfine Microstructure,Shanghai Institute of Ceramics,Chinese Academy of Sciences,Shanghai 201899,China;School of Materials Science and Engineering,Guilin University of Electronic Technology,Guilin 541004,China;Guangxi Key Laboratory of Information Materials,Guilin University of Electronic Technology,Guilin 541004,China;Center of Materials Science and Optoelectronics Engineering,University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]上海大学材料科学与工程学院,上海200444 [2]中国科学院上海硅酸盐研究所,高性能陶瓷和超微结构国家重点实验室,上海201899 [3]桂林电子科技大学材料科学与工程学院,桂林541004 [4]桂林电子科技大学广西信息材料重点实验室,桂林541004 [5]中国科学院大学材料与光电研究中心,北京100049

出　　处：《科学通报》2021年第23期2971-2990,共20页Chinese Science Bulletin

基　　金：国家重点研发计划(2016YFB0901600);国家自然科学基金(U1830113,51772313,21975276);上海市科学技术委员会项目(16DZ2270100)资助。

摘　　要：金属锂负极因其超高的理论比容量和极低的氧化还原电势成为下一代可充电池的"圣杯"负极材料,高能量密度的锂金属电池有望成为后锂离子电池时代最具商业应用潜力的电化学储能系统.但是负极锂枝晶的生长带来了极大的安全隐患,"死锂"的积累和电解质的过度消耗造成了电池循环稳定性的下降,这些严重阻碍了锂金属电池的商业应用.近年来,国内外学者通过电极结构设计、固态电解质、隔膜修饰、保形包覆、添加剂等手段有效抑制了枝晶的生长.本文着重介绍了功能性添加剂和保形包覆两种策略的成功实例,通过在负极-电解质界面处注入富氟成分或引入亲锂性基团以均匀化锂离子流,从而实现稳定且无枝晶的负极循环,为锂金属电池的发展提供有益的见解.Lithium(Li)metal is regarded as a"Holy Grail"anode for next-generation rechargeable batteries due to its ultrahigh theoretical specific capacity and extremely low redox potential.Lithium metal batteries(LMBs)with high energy density have received extensive research attentions and been considered to be one of the most promising candidates for the post lithium-ion battery era.However,the intrinsic properties of Li metal hinder the practical application of LMBs,including severe safety concern and poor cycling stability.The closely related problems include:(1)The growth of Li dendrites to penetrate the polymer separator and cause a short circuit of cell;(2)the infinite volume expansion and contraction during Li plating and stripping processes to cause the continuous exposure of fresh Li and consumption of electrolyte;(3)the accumulation of electrochemically inert dead Li so as to increase the cell impedance and decease the Coulombic efficiency.Therefore,it is essential to address the above issues in order to achieve the safe and stable Li metal anode.In the past years,some models about the growth of Li dendrites have been proposed,and they can help us understand the dendrite growth mechanisms and guide the direction toward the design of prospective anodes.And some strategies such as anode structural design,solid-state electrolyte,separator decoration,artificial solid-state electrolyte interphase(SEI),additives and so on have been demonstrated to enable an effective suppression or alleviation of the growth of Li dendrites.Herein,we highlight the strategies of functional additives and conformal coating,especially their impacts on the composition and structure of the electrode/electrolyte interface,and thus on the homogenization of the Li-ion flux and formation of the uniform deposition of Li.Small amounts of additives can react with Li to regulate the properties of SEI,or disperse in the electrolyte as an ion transport channel to modulate the distribution of Li-ion flux.The construction of a conformal coating with rich

关 键 词：锂金属电池 金属锂负极 添加剂 保形包覆 界面调控 

分 类 号：TG146.26[一般工业技术—材料科学与工程] TM912[金属学及工艺—金属材料]