LiNi_(0.5)Mn_(1.5)O_4-Li_(1.3)Al_(0.3)Ti_(1.7)(PO_4)_3复合正极材料的制备及性能研究

Study on preparation and performance of LiNi_(0.5)Mn_(1.5)O_4-Li_(1.3)Al_(0.3)Ti_(1.7)(PO_4)_3 anode material

采用溶胶-凝胶法制备尖晶石型高电压正极材料LiNi_(0.5)Mn_(1.5)O_4(LNMO),并利用高速球磨和高温煅烧的方法制备复合材料LiNi0.5Mn1.5O4-Li1.3Al0.3Ti1.7(PO4)3。分别采用X射线衍射仪(XRD)、电子扫描显微镜(SEM)对其物相、形貌进行表征,采用循环伏安(CV)、交流阻抗和充放电测试对电化学性能测试分析。结果表明:LNMO-LATP复合材料具有比LNMO更稳定的循环性能和更好的倍率性能,室温下在0.05C放电时,LNMO包覆20%(wt,质量分数,下同)LATP、LNMO包覆40%LATP和LNMO的首次放电容量分别为120mAh/g、78mAh/g和100mAh/g。LNMO包覆20%LATP显示出更好的倍率性能。

High voltage spinel-type anode Material LiNi0.5Mn1.5O4(LNMO)was prepared by sol-gel method,and composite high voltage materials LiNi0.5Mn1.5O4-Li1.3Al0.3Ti1.7(PO4)3 were prepared by high speed ball milling and high temperature calcination.The phase,surface morphology and electrochemical properties of prepared powders were characterized by X-ray diffraction,scanning electron microscopy,battery test electrochemical workstation and electrochemical impedance spectros-copy,respectively.The results showed that LATP with amorphous strcture covered closely the surface of LNMO.LATP layer can protect the electrode material surface and improved the dual role of lithium ion conductive,reduced the side reaction of electrode process,decreased the electrochemical polarization,provided more lithium ions diffusion channels.At room temperature in the 0.05 Cdischarge,LNMO doped 20%LATP,LNMO doped 40%LATP and the initial discharge capacity of LNMO was 120 mAh/g,78 mAh/g and 100 mAh/g.LNMO doped 20%LATP showed better rate performance.