基于粒径级配的天然石墨对锂离子电池性能的优化  

Optimization of lithium-ion battery performance based on natural graphite particle size gradation

作　　者：王泽斌 王显超 张萱 李家烨 刘欢 温青[1,2] 赵婧 王贵领 WANG Zebin;WANG Xianchao;ZHANG Xuan;LI Jiaye;LIU Huan;WEN Qing;ZHAO Jing;WANG Guiling(College of Materials Science and Chemical Engineering,Harbin Engineering University,Harbin 150001,China;Technology Research and Development Department,Heilongjiang Hachuan Carbon Materials Technology Company Limited,Jixi 158100,China;Production and Technology Department,China National Building Material Graphite New Material Company Limited,Beijing 100089,China)

机构地区：[1]哈尔滨工程大学材料科学与化学工程学院,哈尔滨150001 [2]黑龙江哈船碳材料科技有限公司技术研发部,鸡西158100 [3]中建材石墨新材料有限公司生产技术部,北京100089

出　　处：《黑龙江大学自然科学学报》2024年第6期663-671,共9页Journal of Natural Science of Heilongjiang University

基　　金：国家自然科学基金资助项目(52402106);鸡西市自然科学基金重点项目(JKZT2022R01,JKZT2022R03)。

摘　　要：采用碱酸法对天然石墨进行纯化,获得了一系列纯化产品。通过粒度分级分析,选取鳞片石墨、9μm球形石墨、10μm球形石墨、17μm球形石墨以及21μm球形石墨作为锂离子电池的负极材料,使用X射线衍射仪(X-ray diffraction,XRD)、扫描电子显微镜(Scanning electron microscope,SEM)和激光粒度测试仪等对石墨材料的基本理化性质进行表征,并探究了不同类型石墨的循环性能和倍率特性。研究发现,较小粒径的球形石墨在循环性能和倍率能力方面表现更为优异,但其成本也增加了一倍。因此,选择粒径为17μm的石墨作为常规产品,其在1.0 A·g^(-1)下具有301 mA·h·g^(-1)的放电比容量。通过粒径级配引入9μm小粒径石墨,对17μm石墨的粒度分布进行了优化,在不改变石墨层间距的情况下,有效提升了其锂存储性能。当9μm粒径石墨颗粒的质量分数达到30%时,其在高电流密度下的性能增强效果优于低电流密度,在1.0 A·g^(-1)的电流密度下具有约315 mA·h·g^(-1)的放电比容量。The alkali-acid method was used to purify natural graphite,obtaining a series of purified products.Through particle size grading analysis,flake graphite,9μm spherical graphite,10μm spherical graphite,17μm spherical graphite,and 21μm spherical graphite were selected as the negative electrode materials of lithium-ion batteries(LIBs).The basic physicochemical properties of these graphite materials were characterized using XRD,SEM,and laser particle size analyzers.The cycle performance and rate characteristics of different types of graphite were investigated.The researches show that smaller particle-sized spherical graphite exhibits superior cycle performance and rate capability,although the cost doubles.Consequently,17μm spherical graphite is chosen as the standard product,as it maintains a discharge capacity of 301 mA·h·g^(-1)at 1.0 A·g^(-1).The particle size distribution of 17μm natural graphite was optimized by grading and introducing 9μm small-particle graphite,which effectively enhanced its lithium storage performance without altering the interlayer spacing.When the mass fraction of small graphite particles reaches 30%,the performance enhancement under high current density surpasses that under low current density,leading to a significant improvement in overall electrochemical performance at high current density,with a specific capacity of approximately 315 mA·h·g^(-1)at the current density of 1.0 A·g^(-1).

关 键 词：天然石墨 锂离子电池 球磨法 粒径级配 

分 类 号：O646[理学—物理化学]