非晶态磷酸锂包覆钛酸锂电极在0.01~3.00 V电压范围的性能研究  

Performance of Amorphous Lithium Phosphate Coated Lithium Titanate Electrodes in Extended Working Range of 0.01-3.00 V

作　　者：王影 张文龙 邢彦锋 曹苏群 戴新义[3] 李晶泽[4] WANG Ying;ZHANG Wenlong;XING Yanfeng;CAO suqun;DAI Xinyi;LI Jingze(School of Mechanical and Automobile Engineering,Shanghai University of Engineering Science,Shanghai 201620,China;Faculty of Electronic Information Engineering,Huaiyin Institute of Technology,Huaian 223003,China;College of Materials and Metallurgy,Guizhou University,Guiyang 550025,China;School of Microelectronics and Solid-state Electronics,University of Electronic Science and Technology of China,Chengdu 610054,China)

机构地区：[1]上海工程技术大学机械与汽车工程学院,上海201620 [2]淮阴工学院电子信息工程学院,淮安223003 [3]贵州大学材料与冶金学院,贵阳550025 [4]电子科技大学微电子学与固体电子学院,成都610054

出　　处：《无机材料学报》2021年第9期999-1005,I0002,共8页Journal of Inorganic Materials

基　　金：National Natural Science Foundation of China(51575335);Program for New Century Excellent Talents in University(NCET-10-0296);Science and Technology Commission of Shanghai Municipality(16030501300);Open fund of Jiangsu Laboratory of Lake Environment Remote Sensing Technologies(JSLERS-2019-003);Open Project of Shanghai Key Laboratory of Digital Manufacture for Thin-walled Structures(2019-002)。

摘　　要：长期以来,表面包覆一直是改善锂离子电池电极材料电化学性能的有效手段。本研究采用磁控溅射法将非晶态磷酸锂包覆在Li4Ti5O12电极片表面,修饰后电极表面光滑,形成了均匀的非晶态磷酸锂包覆层。在0.01–3.00 V电压范围的充放电测试结果显示,该包覆层可显著改善电极的倍率性能和循环性能。当充放电电流密度分别为35和1750 mA·g^(–1)时,电池容量可以达到265和151 mAh·g^(–1),远高于未包覆电池的240和22 mAh·g^(–1),并以88 mA·g^(–1)的电流密度进一步充放电200个循环后,仍保留了238 mAh·g^(–1)的高可逆容量。这是由于非晶态磷酸锂包覆层可稳定电解质界面,保持粒子间电子通道的完整性,并在电极表面形成交联离子导电网络,使得改性电极的倍率性能和循环稳定性显著提高。Surface coating has long been an effective means to improve the electrochemical performance of electrode materials for Li-ion batteries.In this study,the traditional micron-sized Li4Ti5O12 anodes are coated with amorphous lithium phosphate by radio frequency(RF)magnetron sputtering.The characterized morphology indicates that the electrodes are covered by a thin amorphous lithium phosphate coating layer,showing a very smooth surface.Both the rate performance and cycle performance of the electrodes are enhanced markedly by the coating layer in the voltage range of 0.01–3.00 V.When the discharge-charge currents are 35 and 1750 mA·g^(–1),the capacities are elevated to 265 and 151 mAh·g^(–1),respectively,which are higher than those of the uncoated ones(240 and 22 mAh·g^(–1)).After further discharge-charged for 200 cycles at 88 mA·g^(–1),the coated electrodes still maintain a high reversible capacity of 238 mAh·g^(–1).This result clearly suggests that the thin layer can stabilize the solid electrolyte interface,maintain the integrity of the interparticle electronic passage and form a cross-linked ionic conducting network for Li4Ti5O12 grains on the surface.

关 键 词：钛酸锂 磷酸锂 阳极 锂离子电池 磁控溅射 

分 类 号：TM912[电气工程—电力电子与电力传动]