摘要
由于电子和信息行业的需要,过去十年锂离子电池得以快速发展.目前,锂离子电池仍呈现需求量增长的趋势,对锂离子电池的安全性要求也越来越高.因此促使寻找一种比碳/石墨材料更安全,循环性能更理想的锂离子电池负极材料以满足电动汽车等新兴行业的需求.尖晶石型Li4Ti5O12作为"零应变材料"具有优异的循环稳定性、价格便宜、容易制备、较高的平台电压和良好的安全性,已成为锂离子动力电池负极材料的研究热点,被认为是目前最具应用前景的锂离子电池负极材料.由于形貌选择对于Li4Ti5O12材料的电化学性能有着至关重要的影响,本文综述了球形、多孔(中空)结构、纳微结构、核壳结构等不同形貌Li4Ti5O12的合成及其性能研究的最新进展;总结了各种形貌的优点,已解决和待解决的问题,常用合成方法以及各自的适应领域;并对Li4Ti5O12材料的发展趋势进行了展望.
Lithium-ion battery has developed rapidly in the past decades due to growing needs of electronic and information industries. Nowadays, the demand for lithium-ion batteries is still increasing and safety requirements are higher and higher. Therefore, exploration of a new anode material that is high safety and excellent cycle ability, as compared to commercial carbon/graphite materials, has been extensively attempted to meet the new need such as electric vehicles industry. Spinel Li4TisO12 as an anode material of power lithium-ion battery has become a research hotspot due to its appealing features such as ＂zero-strain＂ structure characteristic, excellent cycle stability, low cost, simple synthesis, high safety feature and flat charge-discharge voltage plateau （1.55 V vs. Li/Li＋）. It is also considered as one of the most promising anode material for lithium-ion battery. Despite many advantages associated with Li4Ti5O15, it can not meet the need of large-scale applications due to its pretty low electric conductivity （10-13 S.cm-1）, moderate Li＋ diffusion coefficient （10 910-13 cm2.s-1） and theoretical capacity （175 mAhg-1）. Several methods have been utilized to improve the conductivity and energy density of Li4Ti5012, such as synthesis of nano-sized particle, ion doping, doping LigTisO12 with other metals or metal oxides, coating Li4TisO12 with conductive carbons, nitridation on Li4TisOl2 surface and composite anode materials prepared by Li4Ti5Ol2 and other anodes. In addition, unique structure has been proved as an effective way to improve the electric conductivity of the material. Moreover, morphology has also an important effect on electrochemical performances of Li4TisO12 such as specific capacity, specific energy, specific power, high rate performance and cycle life. This review focuses on the present status of different morphologies Li4Ti5012 including spherical structure, porous （hollow） structure, nano-micro structure, core-shell structure, one-dimensional, two-dimensional and three-dimensional nanostructures, then summarized their advantages, re solved and unresolved problems, common synthesis methods and application areas, respectively. At last, the future develop- ment prospects of Li4Ti5Ol2 are presented.
出处
《化学学报》
SCIE
CAS
CSCD
北大核心
2013年第10期1341-1353,共13页
Acta Chimica Sinica
基金
国家自然科学基金(Nos.21206203
21077140)资助~~
