摘要
采用氢氧化物共沉淀法合成了Lix[Ni0.2Mn0.7Co0.1]Oy(0≤x≤2,2≤y≤3)系列锂离子电池正极材料。通过电感耦合等离子体发射光谱(ICP)、X射线衍射(XRD)、扫描电镜(SEM)形貌分析和电化学性能测试对所得样品的成分、结构、形貌和电化学性能进行了表征。ICP元素分析表明,所制备的氢氧化物前驱体的实际组成与理论组成基本一致。XRD物相分析表明,随着x值的变化,材料的结构发生了较大的改变,由最初的尖晶石结构(LiNi0.5Mn1.5O4)过渡到尖晶石-层状复合结构,最后成为α-NaFeO2层状结构。SEM测试表明,随着x值的变化,材料的形貌也发生了很大的改变。电化学性能测试表明,在2.00～4.95 V电压范围内,以20 mA/g的电流充放电,材料依据成分不同,有不同电化学性能。
A series of Lix[Ni0.2Mn0.7Co0.1]Oy（O≤X≤2,2≤y≤3） cathode materials for Li-ion batteries were prepared via a hydroxide co-precipitation method. The products were analyzed by ICP elemental analysis, X-ray diffractometry （XRD）, SEM and electrochemical tests. ICP element analysis shows a good agreement between the nominal and experimental compositions of the precursor. XRD results show that as the lithium content increases, the structure of the materials underwent dramatic changes from spinel-type phase （0≤x≤0.5） to a mixed spinel/layered phase （0.5〈x〈1.5） and then to a completed α-NaFeO2-type structure （1.5≤x≤2）. SEM indicates different morphology depending on different x value. Charge-discharge tests show that materials with different compositions presents different electrochemical behaviors such as the shape of initial charge-discharge curves, capacity and cycleabUity in the voltage range of 2-4.95 V at a constant current density of 20 mA/g.
出处
《电源技术》
CAS
CSCD
北大核心
2013年第2期187-190,共4页
Chinese Journal of Power Sources
基金
科技部"863"项目(2011AA11AA234)
教育部新世纪优秀人才支持计划(NCET-10-0952)
国家自然科学基金(20901058
51272175)
关键词
锂离子电池
层状结构
氢氧化物共沉淀法
复合材料
Li-ion battery
layered structure
hydroxide co-precipitation
composite materials
