石墨对锂离子电池三元正极的改性及性能影响  

Graphite modified LiNi1/3Co1/3Mn1/3O2 cathodes with improved performance for lithium-ion battery

作　　者：任雅 王影 王东征 许志宇 严晓 黄碧雄 REN Ya;WANG Ying;XU Zhiyu;YAN Xiao;HUANG Bixiong(School of Mechanical and Automotive Engineering,Shanghai University of Engineering Science,Shanghai 201620,China)

机构地区：[1]上海工程技术大学机械与汽车工程学院

出　　处：《储能科学与技术》2019年第5期935-940,共6页Energy Storage Science and Technology

基　　金：上海市科学技术委员会项目(15110501100);上海大学青年教师培训项目(E1-8500-17-022-ZZGCD15103);国家自然科学基金(51705306)

摘　　要：通过丝网印刷方法用石墨改性LiNi1/3Co1/3Mn1/3O2(NCM)电极片的表面。采用X射线衍射(XRD)和扫描电子显微镜(SEM)表征未改性和改性电极片的晶体结构和形貌特征,恒流充放电测试评估两种样品的电池性能,CV和EIS测试比较两种样品的电化学极化程度。结果表明,改性NCM电极的晶体结构没有明显变化;在改性电极片的表面上检测到了片状石墨;在截止电压为4.3 V的条件下改性样品比未改性样品具有更好的循环性能和倍率性能;石墨印刷的样品可以减缓电化学极化的增加。To reduce the contact between the cathodes and electrolyte,the surface of the LiNi1/3Co1/3Mn1/3O2(NCM)cathode was modified with graphite by screen printing.The X-ray diffraction(XRD)test results show that the crystalline structure of the modified NCM cathodes did not change obviously.The morphology of the pristine and modified NCM cathodes were characterized by scanning electron microscopy(SEM),and the results revealed that flake graphite were detected on the surface of the modified NCM cathodes.The performance of both cathodes were evaluated by galvanostatic charge and discharge tests,and it could be concluded that the modified NCM cathodes have better cycling performance and high rate capability than the pristine NCM samples at a cut-off voltage of 4.3V.The results of the CV and EIS test showed that the additional graphite could slow down the increase of electrochemical polarization.In conclusion,the rate capability and cycling performance of the modified NCM were improved.

关 键 词：LiNi1/3Co1/3Mn1/3O2电极片 丝网印刷 石墨 表面改性 电化学性能 

分 类 号：TM912.9[电气工程—电力电子与电力传动]