预锂化法制备高首圈库伦效率的SnO2-Fe2O3@C负极材料

Preparation of SnO2-Fe2O3@C anode with high initial coulombic efficiency by pre-lithization method

将SnO2-Fe2O3@C负极材料与金属锂片同时浸泡在商用二元电解液中,对SnO2-Fe2O3@C负极材料进行预锂化处理以提高该负极材料的首圈库伦效率。通过XRD、SEM和TEM分析了预锂化时间对材料晶相结构和表面微观形貌的影响。恒流充放电测试结果表明预锂化时间为8小时得到的SnO2-Fe2O3@C负极材料的首圈库伦效率高达94%,在0.2A·g^-1的电流密度下循环100圈后仍有862mAh·g^-1的可逆容量,容量保持率为89.3%。

The SnO2-Fe2O3@C anode materials were pre-lithiated by immersing the SnO2-Fe2O3@C anode materials and lithium foil in binay electrolyte simultaneously to improve the initial coulombic efficiency of SnO2-Fe2O3@C anode materials.X-ray diffraction(XRD),scanning electron microscope(SEM)and transmission electron microscope(TEM)were utilized to analyzethe effect of pre-lithization time on the crystal structure and surface morphology of the materials.The results of galvanostatic charge-discharge tests showed that the initial coulombic efficiency of SnO2-Fe2O3@C anode obtained after 8 hours of pre-lithization was 94%,moreover,the reversible capacity after 100 cycles at 0.2 A·g^-1 was 862.7mAh·g^-1 with a retention of 89.3%.