Surface decoration of mesocarbon microbeads with multifunctional TiNbO_(4-x)@C coating layer as high rate and stable anode of Li-ion batteries  

作　　者：Jia-Mei Lai Zhi-Min Zou Yu Bai Yu-Tao Xing Chun-Hai Jiang 

机构地区：[1]Fujian Provincial Key Laboratory of Functional Materials and Applications,Institute of Advanced Energy Materials,School of Materials Science and Engineering,Xiamen University of Technology,Xiamen 361024,China [2]Shanghai XFH Science and Technology Development Co.,Ltd.,Shanghai 200949,China [3]Fujian XFH New Energy Materials Co.,Ltd.,Yong'an 366000,China [4]Shenzhen XFH Science and Technology Co.,Ltd.,Shenzhen 518071,China [5]Laboratorio de Microscopia Eletronica de Alta Resolucao,Centro de Caracterizagao Avangada Para a Industria de Petroleo(LaMAR/CAIPE),Universidade Federal Fluminense,Niteroi,RJ 24210-346,Brazil

出　　处：《Rare Metals》2024年第5期2053-2066,共14页稀有金属（英文版）

基　　金：supported by the Natural Science Foundation Project of Fujian Province(Nos.2020J01287 and 2020H0024)。

摘　　要：Surface modification of graphite anode with electroactive matters has been proven of a more practical strategy in enhancing the performance of Li-ion batteries than exploring alternative novel anode materials.Herein,rutile TiNbO_(4-x) nanoparticles with a tunnel structure are employed as multifunctional decoration substances in combination with a carbon coating layer to improve the rate and cycle properties of mesocarbon microbeads(MCMBs).As compared to pristine MCMB,the Li^(+)diffusion coefficients of the composite anodes are enhanced due to the synergistic effect of TiNbO_(4-x)@C.Meanwhile,the overcharge and voltage polarization of the composite anodes at high rate are obviously minimized due to the current sharing effect of the high-potential TiNbO_(4-x).Moreover,the amorphous Li_(y)TiNbO_(4-x) converted from TiNbO_(4-x) in the initial lithiation process can deliver pseudocapacitive capacity to the composite anodes from the second cycle.All of these functions of TiNbO_(4-x)@Ccoating layer have directly contributed to the improved rate and cycle performance of the MCMB/TiNbO_(4-x)@C composite anodes.The one containing 12.0 wt%TiNbO_(4-x) exhibits a high reversible specific capacity of 118 m Ah·g^(-1)at 10C(1C=372 m A·g^(-1)),together with a high capacity retention of 90.9%after 300 cycles at 3C,which are all much superior to those of pristine MCMB.

关 键 词：Li-ion batteries MCMB TiNbO_(4-x)@C Surface decoration Rate capability 

分 类 号：TB306[一般工业技术—材料科学与工程] TM912[电气工程—电力电子与电力传动]