尖晶石型LiNi_xMn_(2-x)O_4锂离子正极材料的电化学性能

Electrochemical properties of LiNi_xMn_(2-x)O_4 as positive for lithium ion batteries

采用Pechini法在 80 0℃空气中焙烧 6h制备LiNixMn2 -xO4试样 (x =0 ,0 .0 5 ,0 .1,0 .2 ,0 .3,0 .4 ,0 .5 )。经XRD测试表明除LiNi0 .5Mn1.5O4以外 ,其它的试样均为纯净的尖晶石结构。尖晶石LiNixMn2 -xO4试样电极在 3.3～ 4 .5V以及 4 .5～ 4 .8V范围内的电化学性能测试表明 :在 3.3～ 4 .5V范围内 ,试样初始充放电容量随Ni元素掺杂比例的增加而降低 ;在 4 .5～ 4 .8V范围内 ,试样初始充放电容量随Ni元素掺杂比例的增加而增大 ;在 3.3～ 4 .8V范围内 ,试样总的初始容量基本不变 ;在 3.3～ 4 .5V范围内 。

LiNi x Mn 2- x O 4( x =0, 0.05, 0.1, 0. 2, 0.3, 0.4, 0.5)were prepared by Pechini method at 800 ℃in air for 6 h. A ll compounds show a single phase except for LiNi 0.5 Mn 1.5 O 4 based o n the XRD. The initial charge and discharge capacity of LiNi x Mn 2- x O 4 decrease with increase of substituted Ni content in 3.3～4.5 V range; but increase with increase of substituted Ni content in 4.5～4.8 V range. The t o tal first charge and discharge capacity of LiNi x Mn 2- x O 4 are ba sically unchanged in 3.3～4.8 V range. The cycle performance is enhanced with i ncrease of substituted Ni content.