Li_4Ti_5O_(12)/C材料在高功率锂离子电池中的性能

High power lithium ion battery using Li_4Ti_5O_(12)/C as anode material

电动车和混合动力车需要高倍率放电、长寿命和安全的化学电源。采用模板技术制备Li4Ti5O12/C复合材料,测试了材料的粉末X射线衍射图谱,结果显示材料为尖晶石型结构,并用扫描电镜观察材料的微观形貌,材料颗粒粒径在1μm左右。以Li4Ti5O12/C复合材料为负极材料,正极材料采用LiFePO4,组装18650型低电压的锂离子电池。该类低电压锂离子电池具有1.8 V的电压,能够在1 C^12.5 C等倍率条件下充放电,体积比能量为98~108 Wh/L,质量比能量为44.3~48.4 Wh/kg。使用Li4Ti5O12/C复合材料为负极的低电压锂离子电池显示了良好的循环稳定性。因此,这种高功率低电压锂离子电池可应用于动力车和混合动力车。

High-rate batteries with long cycle life and security are necessary for electric vehicle and hybrid electric vehicle.Li4Ti5O12/C composite material was synthesized by template method.The material was characterized by powder X-ray diffraction and scanning electron microscope.The phase structure of Li4Ti5O12/C composite material is spinel and the average particle size is 1 μm.The 18650 lithium ion batteries with Li4Ti5O12/C material as anode and LiFePO4 material as cathode were prepared.The normal voltage of these batteries is 1.8 V.The batteries were charged and discharged at 1 C,5 C,10 C and 12.5 C rate,respectively.The volumetric specific energy is 98-108 Wh/L and weight specific energy is 44.3-48.4 Wh/kg.The low-voltage lithium ion batteries exhibit good cycle life and satisfy the needs of electric vehicle and hybrid electric vehicle.