A multifunctional separator with Mg(OH)2 nanoflake coatings for safe lithium-metal batteries  

作　　者：Dian-Hui Han Meng Zhang Peng-Xian Lu Yun-Lu Wan Qiu-Ling Chen Hong-Yu Niu Zhi-Wei Yu 

机构地区：[1]School of Materials Science and Engineering,Henan University of Technology,Zhengzhou 450007,Henan,China [2]Zhengzhou Key Laboratory for Clean Energy,Henan University of Technology,Zhengzhou 450007,Henan,China

出　　处：《Journal of Energy Chemistry》2021年第1期75-83,I0003,共10页能源化学（英文版）

基　　金：supported by the Natural Science Project from Science and Technology Department of Henan Province (172102410034);National Natural Science Foundation of China (NSFC-U1604120)。

摘　　要：Dendrite growth and thermal runaway induce serious safety hazards,impeding the practical applications of lithium metal batteries(LMBs).Although extensive advances have been attained in terms of LMB safety,most work only focus on a single aspect at a time.This paper reports a multifunctional separator coated by Mg(OH)2 nanoflakes with various excellent properties including electrolyte wettability,ionic conductivity,Li+ transference number,puncture strength,thermal stability and flame retardance.When used in LMBs,the Mg(OH)2 nanoflake coatings enable uniform Li+ distributing,which makes it homogeneous to deposit lithium,realizing effective dendrite suppression and less volume expansion.Meanwhile,Mg(OH)2 coatings can ensure LMBs are in normal conditions without thermal runaway until 140 ℃.A part of lithium can be converted into Li+ ions by Mg(OH)2 during repeated charge/discharge cycles,not only reducing the risk of separator damage and consequent short circuit,but also replenishing the capacity loss of LMBs.The Mg(OH)2 nanoflakes can coat on all kinds of commercial separators to improve their performances,which offers a facile but effective strategy for fabricating multifunctional separators and a comprehensive insight into enhancing LMB safety.

关 键 词：Dendrite-free Thermal stability Li metal batteries Multifunctional separators Mg(OH)2 nanoflakes 

分 类 号：TM912[电气工程—电力电子与电力传动] TB383.1[一般工业技术—材料科学与工程]