摘要
采用直流电弧等离子体气相蒸发法制备出球状Al纳米粒子,对其进行了XRD、TEM以及脱/嵌锂离子循环性能的表征。Al粒子大小约为100 nm,表面包覆一层厚度不到1 nm的非晶氧化物。将Al纳米粒子与导电剂、黏结剂按一定比例混合得到负极极片,在手套箱中组装成电池。将电池在不同的电流密度下进行充放电试验,由首次充放电曲线及前10次循环性能曲线发现,电流密度最小的Al电极首次放电容量最大,为951.9 mAh/g,首次容量损失也最大,其循环稳定性能也相应变差;而电流密度最大的Al电极首次放电容量为879.7 mAh/g,其循环稳定性能最佳。首次放电结束后,对电极材料重新表征,发现只出现了AlLi、Al2Li3两种化合物,这与测试所得的放电容量大小相符合。
Aluminum nanoparticles were fabricated by a physical vapor condensation method（DC arc discharge）.The samples were characterized by X-ray diffraction（XRD）,transmission electron microscope（TEM） and galvanostatic cycling.Al particle,about 100 nm,is coated by amorphous Al2O3.Anode slurries prepared were consisted of Al powder,acetylene black and polyvinylidene fluoride（PVDF） binder.The effects of current density on the electrochemical properties were investigated.Al electrode in the minimal current density delivers the highest initial discharge capacity（Li intercalation process） of 951.9 mAh/g but cycle life is poor.Al electrode in the maximal current density delivers initial discharge capacities of 879.7 mAh/g and possesses relatively good cycleability.After the initial discharge,Al electrode was characterized by XRD and TEM.Only two composites（AlLi and Al2Li3） are found,which corresponds with the initial discharge capacity.
基金
高等学校博士学科点专项科研基金资助项目(20100041110032)
