氧化石墨修饰水热合成梭形LiFePO_4/C正极材料

Spindle LiFePO_4/C Cathode Material Synthesized by Hydrothermal Method with Graphite Oxide Modified

以氧化石墨为模版剂,以FeSO_4·7H_2O、H_3PO_4、LiOH·H_2O、水合肼为原料,采用水热法在185℃下分别反应2、4、6 h合成磷酸铁锂前驱体,然后高温煅烧合成新型梭形LiFePO_4/C复合锂离子电池正极材料。通过TGDSC确定高温煅烧温度为600℃,采用XRD、SEM、LAND电池测试仪等分析测试手段对材料的结构、形貌及电化学性能进行测试,发现:185℃/(4 h)水热反应的前驱体经600℃/(2 h)获得的梭形LiFePO_4/C材料具有较好的电化学性能,室温、0.2 C下,2.7~4.2 V电压范围进行充放电测试,放电比容量达141.2 m Ah/g。

Using graphite oxide as template and FeSO4·7H2O、H3PO4、LiOH·H2O,hydraine hydrate as material, the precursor of lithium iron phosphate is synthesized for 2,4,6 h respectively at temperature of 185 ℃ by hydrothermal method. Then the spindle LiFePO4/C cathode material is obtained by high temperature calcination. High calcination temperature is 600 ℃ with confirmed by TG - DSC. The structure, morphology and electrochemical properties of materials are tested by XRD, SEM, LAND battery tester and other test methods. The results shows：the sample which synthesized by hydrothermal method at 185 ℃/4h and subsequent high temperature sintering at 600 ℃/（2h） showes excellent electrochemical performances. The discharge capacity of the sample is 141.2 mAh/g at room temperature,0.2 C when a cell （ LiFePO4/C/Li） is cycled in 2.7 - 4.2 V.