摘要
二次电池由于具有高能量密度、宽电化学窗口和高可逆性等特点,得到了广泛的应用,然而传统二次电池使用的有机电解液成本高,且存在易燃、有毒等安全隐患。与有机电解液相比,水系电解液具备离子电导率高、功率密度高、生产条件简单和成本低等优点。因此,使用中性或弱酸性水系电解液的新型二次水系电池受到了越来越多研究人员的关注。其中,金属锌具有储量丰富、无毒、过电位低(-0.76 V)和理论容量高(820 mAh·g^-1)等优点,使得水系可充电锌离子电池在大型储能系统中极具吸引力。然而,金属锌作为负极会存在一些缺陷:如锌枝晶、库伦效率低、利用率不足等。其中锌枝晶往往与锌沉积/溶解不均匀有关,而库伦效率低和利用率不足则与锌电极的析氢反应和生成不可逆副产物有关。目前,研究人员对水系锌离子电池负极材料的研究主要集中在以下四个方面:(1)优化锌电极结构,将锌负极的结构设计为三维、多孔型,为锌的沉积/溶解提供更多的位点并限制锌枝晶等产物的生成;(2)添加剂的应用,将无机物或有机物添加到负极材料中,改变锌的析氢电位、腐蚀电位、极化行为,降低锌的析氢腐蚀,减少副产物等;(3)添加功能保护层,不仅提高金属锌的耐蚀性,而且能够引导锌的均匀沉积/溶解,抑制锌枝晶的生长;(4)添加导电剂,将导电剂添加到锌负极中,一方面可以提高电极的导电性,另一方面也可以促进Zn^2+的均匀沉积/溶解。上述改性锌负极的方法能够有效抑制锌枝晶的生成,减少锌负极形变和提高金属锌的利用率,在一定程度上有效提高了水系锌离子电池的库伦效率和循环稳定性。本文首先简单介绍了水系锌离子电池的结构,然后重点阐述了目前对水系锌离子电池负极材料的研究进展,包括锌负极材料面临的挑战和优化策略等方面。最后,本文对水系锌离子电
Secondary batteries have been widely applied due to their high energy density,wide electrochemical window,and highly reversible cycle,however,the organic electrolytes of traditional secondary batteries are expensive,flammable and toxic.Compared with organic electrolytes,aqueous electrolytes have the advantages of high ionic conductivity,high power density,simple manufacturing and low cost.Therefore,researchers pay more attentions to novel secondary aqueous batteries which using a neutral or weakly acidic inorganic-salt aqueous solution as electrolyte.In particular,metal zinc has been considered as promising anode material for large-scale energy storage owing to its abundant reserves,nontoxicity,low redox potential(-0.76 V)and high theoretical capacity(820 mAh·g^-1).Hence,the rechargeable aqueous zinc ion batteries(AZIBs)is extremely attractive in recent years.In fact,AZIBs still face the problems of the zinc dendritic,low plating/stripping columbic efficiency and insufficient utilization of zinc anode.The zinc dendritic usually originate from uneven Zn^2+distribution on the Zn foil,while low coulombic efficiency is caused by hydrogen evolution reaction of zinc electrode and generation of irreversible side-products.At present,the optimization of zinc anode materials for AZIBs have been focused on the following four points:(ⅰ)Optimizing the structure of the zinc electrode.Zinc negative electrode with 3D or porous type structure have more sites for zinc deposition/dissolution and limit the growth of zinc dendrite.(ⅱ)Application of additives.Adding inorganic or organic substances to the negative electrode material,which could change the hydrogen evolution potential,corrosion potential and polarization behavior of zinc,reduces hydrogen evolution corrosion of zinc and the formation of side-products,etc.(ⅲ)Formation of the functional protection layer.The protection layer is beneficial to the uniform deposition/dissolution of zinc and inhibits the growth of zinc dendrites.(ⅳ)Introducing the conductive material.O
作者
蓝彬栩
张文卫
罗平
汤臣
唐稳
左春丽
董仕节
陈丽能
LAN Binxu;ZHANG Wenwei;LUO Ping;TANG Chen;TANG Wen;ZUO Chunli;DONG Shijie;CHEN Lineng(School of Materials and Chemical Engineering,Hubei University of Technology,Wuhan 430068,China;Hubei University of Economics,Wuhan 430205,China;State Key Laboratory of Advanced Technology for Materials Synthesis and Processing,Wuhan University of Technology,Wuhan 430070,China)
出处
《材料导报》
EI
CAS
CSCD
北大核心
2020年第13期13068-13075,共8页
Materials Reports
基金
国家自然科学基金(51771071)
湖北省教育厅科学研究指导项目(B2019046)。
关键词
水系锌离子电池
锌负极材料
能量存储
锌枝晶
aqueous zinc ion battery
zinc anode materials
energy storage
zinc dendritic
