摘要
用流变相反应方法合成一种非化学计量比尖晶石型化合物LixMn1.93Gd0.02O4,先制备先驱物,然后在一定温度下,通过先驱物的热分解制得目标产物。用X射线衍射光谱法(XRD)、X射线光电子光谱法(XPS)、红外光谱技术(IR)对合成的产物进行表征,用电感耦合等离子体(ICP)方法确定目标产物的组成。用透射电镜的方法观测晶体颗粒的大小与形状,并对其电化学性质进行研究。实验结果表明该化合物作为正极材料具有优良的电化学性能,在3.0～4.4V电压范围内以电流密度为1mA·cm-2进行充放电时,其初始放电容量为124mAh·g-1,电池经50次循环后,放电容量仍保持在95%以上。这一制备方法为无机材料合成提供了一条简单、有效、可行的路线。
A new spinel phase compound (LixMn1.93Gd0.02O4) was synthesized by using the rheological phase reaction method. At first, the precursor was prepared, then it was pyrolyzed to form a spinel phase.The new spinel phase was characterized by XRD, XPS and IR spectra. The composite of expected compound was determined by ICP techniques. The particle size and shape of the spinel phase had been observed by the method of TEM. The electrochemical properties of this kind material were also investigated. The experimental result showed that the new material as cathode material has both higher initial discharge capacity (124 mAh·g-1) and more extended cycle life in lithium-ion cells working at room temperature over voltage range of 3.0 V to 4.4 V. The discharge capacity is retained by 95% after 50 cycles. The method provided a simple, practicable and effective rout for inorganic material synthesis.
出处
《电源技术》
CAS
CSCD
北大核心
2004年第11期667-670,共4页
Chinese Journal of Power Sources
基金
湖北省自然科学基金资助项目(2001ABB103)
关键词
锂离子蓄电池
锂锰氧化物
尖晶石
流变相反应
lithium-ion battery
lithium manganese oxide
spinel
rheological phase reaction
