摘要
对行星球磨法制备石墨烯导电浆材料进行了研究,通过改变石墨原料粒径、浆料固含量、磨球直径、球磨转速和球磨时间5个参变量的实验,对球磨工艺参数进行优化,使电阻率比磨前降低80%.通过扫描电子显微镜观察到石墨片层被破碎和剥离,原子力显微镜检测到有厚度为4~15 nm石墨薄片,在拉曼光谱中有显著的石墨烯特征峰G峰和2D峰,IG/I2D=2.475表明浆料中含有少层石墨烯.从导电通道的形成方面,模拟球磨效率的影响,分析了导电性提升原因.将制备的浆料作为钴酸锂电池正极材料的导电剂,装配为扣式电池,进行倍率性能测试,5C以上的高倍率性能优于传统导电剂的锂电池.
Different type of graphene slurry were prepared with planetary ball milling in different experimental conditions, including the particle size of graphite, the solid content of slurry, the diameter of grinding ball, the rotational speed and the milling time. The parameters of ball milling were optimized in terms of the resistance analysis, yielding the slurry with a resistivity decreased by 80%. Scanning electron microscopy(SEM) and atomic force microscopy(AFM) were used to analyze the morphology of the slurry, revealing that the size and the thickness of some broken and exfoliated graphite sheet layer are 300 nm and 4~15 nm, respectively, and there are obvious G and 2 D peaks in Raman spectra. IG/I2 D=2.475 shows that there are few layer graphene in the slurry. Ising model was used to simulate the influence of grinding efficiency on the formation of conductive channels. LiCoO2 lithium-ion batteries were assembled using the prepared slurry as the conductive agent. It was found that the high rate performance of the battery above 5 C was more superior to that of the traditional conductive agent.
作者
蔡晓明
梁惠明
吕鉴
郭伟华
侯元捷
戴洪涛
吴张永
CAI Xiaoming;LIANG Huiming;LV Jian;GUO Weihua;HOU Yuanjie;DAI Hongtao;WU Zhangyong(Faculty of Mechanical and Electrical Engineering,Kunming University of Science and Technology,Kunming 650500,China;D&R Graphene Research Institute,Dongguan 523069,Guangdong,China)
出处
《昆明理工大学学报（自然科学版）》
CAS
北大核心
2020年第4期15-22,共8页
Journal of Kunming University of Science and Technology(Natural Science)
基金
国家自然科学基金项目(11674136,51165012)
关键词
钴酸锂电池
石墨烯导电剂
行星球磨
电阻率
导电通道
LiCoO2 lithium-ion battery
graphene conductive agent
planetary ball mill
resistivity
conductive channel
