以LiOH·H2O,含镉球状Ni(OH)2和Co2O3为原料,采用改进固相反应法合成镍系复合氧化物LiaNi0.78Co0.2Cd0.02O2锂离子电池正极材料,并通过ICP＿AES,XRD,SEM,TEM及电化学性能测试对该材料进行表征.实验表明,由Co和Cd部分取代Ni元素的复合正极材料LiaNi0.78Co0.2Cd0.02O2仍具有较完好的层状结构,表面分布均匀,颗粒粒径分布窄,且电化学性能稳定.常温下具有较高的可逆容量和优异的循环稳定性,其可逆容量最高达157.8mAh/g,循环50次后容量仍保持138.3mAh/g左右.
袁荣忠
,
瞿美臻
,
于作龙
. 镍系复合氧化物Li_aNi_(0.78)Co_(0.2)Cd_(0.02)O_2的合成及电化学性能[J]. 电化学, 2003
, 9(2)
: 211
-216
.
DOI: 10.61558/2993-074X.1507
The nickel_based complex oxide LiaNi0.78Co0.02O2 cathode materials for lithium_ion rechargeable batteries was synthesized by the improved solid_state reaction method with LiOH·H2O, ball_like Cd_doped Ni(OH)2 and Co2O3 as raw materials. The analysis ICP_AES proved that the as_prepared compounds were near the stoichiometric form. The XRD, SEM and electrochemical characteristics testing were also carried out. The results showed that the complex cathode material LiaNi0.78Co0.2Cd0.02O2 has layered structure, homogeneous surface distributions,uniform particles with good crystal morphology as well as stable electrochemical performances. At ambient temperature the resulted materials have a high reversible capacity and good cycling stability.Its highest initial reversible capacity is more than 157.8 mAh/g and still kept at 138.3 mAh/g after 50 continuous cycles.
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