ALD沉积超薄涂层改善高镍LiNi_(0.96)Co_(0.03)Mn_(0.01)O_(2)正极材料的电化学性能  

Improvement of electrochemical performance of high-Ni LiNi_(0.96)Co_(0.03)Mn_(0.01)O_(2) cathode materials by ALD deposition of ultrathin coatings

作　　者：郑瑶 李荐[1,2] 王利华 李恩熙 ZHENG Yao;LI Jian;WANG Lihua;LI Enxi(School of Materials Science and Engineering,Central South University,Changsha,Hunan Province,410083,China;Hunan Zhengyuan Institute for Energy Storage Materials and Devices,Changsha,Hunan Province,410083,China;College of Mechanical Engineering,Hunan Institute of Science and Technology,Yueyang,Hunan Province,414006,China;School of Chemical Engineering,Qingdao University of Science and Technology,Qingdao,Shandong Province,266042,China)

机构地区：[1]中南大学材料科学与工程学院,湖南长沙410083 [2]湖南省正源储能材料与器件研究所,湖南长沙410083 [3]湖南理工学院机械工程学院,湖南岳阳414006 [4]青岛科技大学化工学院,山东青岛266042

出　　处：《电池工业》2025年第1期13-18,23,共7页Chinese Battery Industry

基　　金：湖南省自然科学基金(2021JJ30794);湖南省科技创新计划(2022RC1086)。

摘　　要：富含镍的层状氧化物正极存在结构不稳定性等问题,特别是当镍含量(质量分数)超过90%时,其循环性能急剧恶化。为了解决高镍材料在长循环和大倍率下容量衰减的问题,本文以LiNi_(0.96)Co_(0.03)Mn_(0.01)O_(2)(NCM9631)正极材料为研究对象,对其进行包覆改性研究。使用原子层沉积技术对NCM9631进行包覆改性,其中具有TiO_(2)涂层的T-NCM9631样品表现出良好的电化学性能。与原始材料相比,T-NCM9631的初始放电比容量从226 mAh/g提高到239 mAh/g,在0.5 C下循环100圈后,容量保持率从73.9%提高至87.95%。超薄TiO_(2)包覆层可以减少活性材料NCM9631与电解质的直接接触,不受HF侵蚀,防止金属溶解,有效阻止材料表面的化学和结构变化,以提高结构稳定性与电化学性能。Nickel-rich layered oxide anodes suffer from inherent structural instability,especially when the nickel content is increased to more than 90%,the cycling performance deteriorates dramatically.In order to solve the serious problem of capacity degradation of high nickel materials under long cycling and large multiplicity,LiNi_(0.96)Co_(0.03)Mn_(0.01)O_(2)(NCM9631)cathode material is used as the object of research in this thesis for the cladding modification study.The coating modification of NCM9631 was carried out using atomic layer deposition technology,in which the TiO_(2)-coated T-NCM9631 samples showed good electrochemical performance,and compared with the original material,the initial discharge specific capacity of T-NCM9631 was increased from 226 to 239 mAh/g,and the capacity retention rate of 100 cycles at 0.5 C was increased from 73.9%to 87.95%.The ultra-thin TiO_(2) cladding reduces direct contact between the active material and electrolyte,protects the active material T-NCM9631 from HF erosion,and prevents excessive metal dissolution.It effectively prevents the chemical and structural changes on the surface of the material,improves the structural stability of the material,and improves the electrochemical performance of the material.

关 键 词：原子层沉积 锂离子电池 高镍正极材料 TiO_(2) Al_(2)O_(3) NCM9631 

分 类 号：TM911[电气工程—电力电子与电力传动]