电池正极材料中Li^+运动特性的~7Li NMR研究

7Li NMR STUDY OF Li + MOTION IN ANODE MATERIALS OF BATTERY

利用变温７ＬｉＮＭＲ实验对Ｌｉ电池正极材料ＬｉＭｎ２Ｏ４和ＬｉＣｏＯ２中Ｌｉ＋的运动特性进行了研究，结果表明，随实验温度的提高，ＬｉＭｎ２Ｏ４的７ＬｉＮＭＲ谱线窄化，表明其中Ｌｉ＋迁移能力增加，而ＬｉＣｏＯ２的谱线无变化．此外随温度提高，ＬｉＭｎ２Ｏ４的７Ｌｉ的Ｔ１变短，而ＬｉＣｏＯ２的Ｔ１变长，产生这种不同变化趋势的原因在于ＬｉＭｎ２Ｏ４和ＬｉＣｏＯ２晶相结构的差异造成其中Ｌｉ＋迁移能力的差别。

The motion of Li + ions in anode materials of battery has been investigated by temperature varying 7Li solid state NMR techniques. The results suggest that with the increase of experimental temperature, the 7Li NMR spectra of LiMn 2O 4 become narrowed, which indicate the increase of mobility of Li +, while those of LiCoO 2 remain unchanged. The changes of T 1 in LiMn 2O 4 and LiCoO 2 show opposite tendency with the increase of temperature because their T 1′s locate on different sides of the utmost point of the T 1-τ c curve.