应用溶胶-凝胶法合成LiNi(0.75-x)Co0.25TixO2(x=0,0.1,0.25)系列正极材料,其结构、形貌、粒度、电化学性能由TG、XRD、SEM和电池充放电测试表征研究表明,材料的电化学性能与钛掺杂量密切相关.在钴含量不变的情况下,随着Ti含量(x)的增加,材料由六方层状结构逐渐向立方结构转变,x=0.25时,出现了立方相与六方相共存.根据实验和理论计算结果简要讨论了钛掺杂对正极材料LiNi0.75Co0.25O2结构和电化学性能的影响.
贺慧
,
程璇
,
张颖
. 钛掺杂对LiNi_(0.75)Co_(0.25)O_2结构与性能的影响(英文)[J]. 电化学, 2006
, 12(3)
: 243
-249
.
DOI: 10.61558/2993-074X.1730
In this study,a series of Co-doped compounds with the formula of LiNi_((0.75-x))Co_(0.25)Ti_(x)O_(2)(x=0,(0.1),0.25)was synthesized by using sol-gel method.Their structure,particle size,electrochemical properties were studied by TG,XRD,SEM and electrochemical tests.It was shown that the structure of materials changed from a hexagonal layered structure to a cubic structure as the x value increased.In particular,a mixture of hexagonal and cubic structure was presented at x =0.25.The electrochemical performance of the materials depended strongly on the amount of Ti doping.Possible effects on the structure and performance of LiNi_((0.75-x))Co_(0.25)Ti_(x)O_(2) due to Ti doping are briefly discussed based upon the experiment and computational results.
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