锂电池正极材料化学及形貌的X射线纳米谱学成像研究  

Nano-Resolution TXM-XANES Study of the Chemistry and Morphology of Lithium Battery Cathode Materials

作　　者：高若阳 张玲 陶芬 汪俊 苏博 毕志杰 杜国浩 邓彪[1,2,3] 肖体乔 GAO Ruo-yang;ZHANG Ling;TAO Fen;WANG Jun;SU Bo;BI Zhi-jie;DU Guo-hao;DENG Biao;XIAO Ti-qiao(Shanghai Institute of Applied Physics,Chinese Academy of Sciences,Shanghai 201800,China;University of Chinese Academy of Sciences,Beijing 100049,China;Shanghai Synchrotron Radiation Facility,Shanghai Advanced Research Institute,Chinese Academy of Sciences,Shanghai 201204,China;College of Physics,Qingdao University,Qingdao 266071,China)

机构地区：[1]中国科学院上海应用物理研究所研究中心,上海201800 [2]中国科学院大学,北京100049 [3]中国科学院上海高等研究院上海光源中心,上海201204 [4]青岛大学物理科学学院,山东青岛266071

出　　处：《光谱学与光谱分析》2024年第5期1239-1244,共6页Spectroscopy and Spectral Analysis

基　　金：国家自然科学基金项目(U1932205,12275343);国家重点研发计划项目(2021YFA1600703,2021YFF0701202,2021YFA1601001)资助。

摘　　要：锂离子电池高镍三元正极材料是储能领域的研究热点之一,多次循环后材料内部化学不均匀性与形貌缺陷,会造成电池失效与性能衰退,深入了解电池容量衰减变化及其原因需要对材料进行快速、高效无损的观测和分析。基于同步辐射的硬X射线全场透射显微镜(TXM)是一种可无损研究物质内部结构且具有纳米分辨的成像技术。随着高亮度、高性能同步辐射光源的发展,同步辐射的TXM技术获得了快速发展,使得TXM成像方法具有更高的实验效率和空间分辨率。X射线纳米谱学成像(TXM-XANES)是将TXM与X射线吸收近边结构谱(XANES)有机结合的成像方法,TXM-XANES能够从纳米尺度上表征微米级能源材料的内部元素空间分布及化学态等信息,解决了常规方法由于表征材料局部区域而缺乏整体表征,或表征集合平均值特性而错过材料局部化学状态变化的问题。TXM-XANES作为基于TXM发展的多模态联合表征技术,已逐渐成为能源材料研究的重要实验方法之一。介绍了上海光源纳米三维成像线站及TXM成像系统,阐述了X射线纳米谱学成像方法的原理及其特点。X射线纳米谱学成像和纳米CT方法对锂离子电池正极高镍层状三元氧化物材料LiNi_(0.6)Co_(0.2)Mn_(0.2)O_(2)(NCM622)粉体进行了表征,获得了纳米尺度下NCM622单颗粒样品中Ni元素化学态的空间分布信息及单颗粒的三维结构信息。对电池材料的三维X射线纳米谱学成像方法进行了介绍和展望。High-nickel ternary cathode materials for lithium-ion batteries are one of the research hot spots in energy storage.After multiple cycles,the internal chemical in homogeneity and morphological defects of the materials will cause battery failure and performance degradation.Understanding changes in battery capacity decay and their causes requires fast,efficient and non-destructive tests of materials.Transmission X-ray Microscope(TXM)based on synchrotron radiation is a nanometer-resolved non-destructively imaging technique for internal structure research.In recent years,with the development of high-brightness and high-performance synchrotron radiation light sources,TXM technology based on synchrotron radiation has developed rapidly,which makes TXM imaging methods have higher experimental efficiency and spatial resolution.X-ray nano-spectral imaging(TXM-XANES)is an imaging method that combines TXM with X-ray Absorption Near Edge Structure(XANES).TXM-XANES can characterize the spatial distribution and chemical state of internal elements of micron-scale energy materials on the nanoscale.It solves the problem of the lack of overall characterization due to the characterization of local regions and the characterization of the average value properties but missing local chemical state changes of materials.As a multimodal joint characterization technology based on TXM,TXM-XANES has gradually become one of the important experimental methods for energy materials research.This paper first introduces the nano-3D imaging beamline in SSRF and its TXM imaging system,then expounds the principle and characteristics of the X-ray nano-spectral imaging method.The powder LiNi_(0.6)Co_(0.2)Mn_(0.2)O_(2)(NCM622)of cathode-high nickel-layeredterary oxide material for lithium-ion batteries was characterized by spectral imaging and nano-CT methods.The spatial distribution information of Ni element chemical state and three-dimensional structure information of single particle in NCM622 single particle samples at the nanoscale were obtained.Fina

关 键 词：纳米谱学成像 全场透射X射线显微镜 锂电池 同步辐射 

分 类 号：O433[机械工程—光学工程]