锂离子电池负极材料钛酸锂研究进展

The recent development of lithium titanate as anode materials for lithium-ion batteries

锂离子电池被广泛应用于移动电子设备,在电动汽车和各类储能系统有良好的应用前景,是未来最具发展前途的储能电池之一。作为一种锂离子电池负极材料,钛酸锂因具有高的脱嵌锂平台电位,优异的循环性能,突出的热稳定性和安全特性而备受重视。总结了钛酸锂负极材料在结构形貌和电化学性能方面的研究进展,对其微纳米化、表面改性和离子掺杂等方面新的研究成果进行了概述。微纳米化可以赋予材料更大的表面积,有助于锂离子迁移,电极材料与电解液可以更好的接触,产生更大的锂离子迁移电流,有利于提升钛酸锂材料倍率性能;表面改性手段主要以碳包覆、金属-钛酸锂复合材料和形成新表面相为主,通过这些手段可以改善材料导电性和提高电池的循环性能;离子掺杂可使部分Ti^(4+)转变为Ti^(3+),提高钛酸锂材料的电子导电性。对钛酸锂作为锂离子电池负极材料未来的发展方向进行了展望。

Lithium-ion batteries are one of the most promising battery systems to be widely used in portable e-lectronics,electric vehicles,and energy storage systems.Lithium titanate （Li4Ti5O12 ）has been intensively in-vestigated as an important anode material for lithium-ion batteries due to its high potential of around 1 .5 5 V （vs. Li/Li＋）during charge and discharge,excellent cycling stability,and high thermal stability and safety.This pa-per reviews the recent advances in structure and electrochemical performance of lithium titanate involving on new preparation methods of micro/macro particle,surface modification and ion doping.The micro/macro parti-cles can provide greater surface area and shorten the migration distance for Li＋.The better contact between the electrode and electrolyte produces benefits transportation of Li＋,which improves the cycling performance of Li4Ti5O12 .The major methods of surface modification are carbon coating,forming Li4Ti5O12/metal composites and modification by new surface phase.Such methods aim to increase the conductivity and improve the cycling per-formance of Li4Ti5O12 .Doping ions increases the electron concentration and electronic conductivity since the partial Ti^4＋ transform to Ti^3＋.The future development of lithium titanate as anode materials in lithium-ion bat-teries is also prospected in this review.