溶胶-凝胶-微波法制备阴阳离子同时掺杂型LiAlxMn2-xOyFz

以LiNO3、Al(NO3)3·9H2O、LiF和MnNO3为原料,通过控制n(Li)/n(Mn)和Al、F掺杂量,溶胶-凝胶-微波法在750℃下合成阴阳离子复合掺杂型Li1.00Al0.05Mn1.95O3.95F0.05电极材料。XRD实验证明Li1.00Al0.05Mn1.95O3.95F0.05为纯尖晶石结构。掺杂适量的Al可以改善材料的循环性能,掺杂氟不但可以不降低材料的初始比容量而且可以显著降低材料在高温使用时的容量损失。Li1.00Al0.05Mn1.95O3.95F0.05在室温条件下的首次放电比容量达到115mAh/g,循环50次后放电比容量仍保持在109mAh/g,即使在55°C的高温,50次的总容量损失率也仅有10.1%。

Anion-cation Synchronous Substitution of LiAlxMn2-xOyFz by Sol-gel-microwave Method

Uing lithium nitrate,aluminium nitrate,lithium fluoride and manganese nitrate as starting materials and controlling the ratio of n(Li) to n(Mn) and the mount of nitrate and fluoride doped,Li_1.00Al_0.05Mn_1.95O_3.95F_0.05 was prepared at 750°C by a sol-gel-microwave method.XRD data indicated that Li_1.00Al_0.05Mn_1.95O_3.95F_0.05 spinel was formed.The test of charge-discharge proved that doping aluminium appropriately could enhance the stability of the material and doping fluoride appropriately not only increased the initial discharge capacity of the material but also improved its cycle stability at high temperature.The initial discharge capacity of Li_1.00Al_0.05Mn_1.95O_3.95F_0.05 was 115 mAh/g and maintained 109 mAh/g after 50 cycles at room temperature,and the decrease was only 10.1% at 55 °C.