摘要
通过固相自引发基团置换反应——流变相法制备出层状LiNi1/3Co1/3Mn1/3O2正极材料,研究了不同烧结温度对材料的结构特性、微观形貌以及电化学性能的影响。结果表明,850℃煅烧20h的样品具有最佳的二维层状结构和阳离子有序度,产物颗粒呈球形,分布均匀,平均粒径约250nm。在2.8~4.3V区间,以80mA/g充放电,首次放电比容量为169mAh/g,30次循环后容量保持率为82.6%。将充电截止电压提高至4.4V,材料的前几次放电容量明显提高,以32mA/g充放电,10次循环后的放电比容量为174mAh/g,其后容量衰减加快,循环稳定性变差。
Layer-structured LiNi1/3Co1/3Mn1/3O2 cathode material was prepared by self-propagating solid-state metathesis-rheological phase method. LiNi1/3Co1/3Mn1/3O2 materials prepared at different sintering temperatures were studied by SEM,XRD and electrochemical test. The result indicates the sample sintered at 850℃,20h has the best two-dimensional layered structure and cationic degree of order. The particle size is 250nm and its distribution is uniform. The initial specific discharge capacity of 169mAh/g is obtained between 2.8-4.3V,at 80mAh/g,and discharge capacity retention rate is 82.6% after 30 cycles. Increasing charge cut-off voltage could improve the previous discharge capacities.The discharge capacity cycled at 32mAh/g is 174mAh/g after 10 cycles in the voltage range of 2.8-4.4V,but after that ,the capacities decay quickly and capacity retention becomes poor.
出处
《功能材料》
EI
CAS
CSCD
北大核心
2010年第5期851-854,共4页
Journal of Functional Materials
基金
国家自然科学基金资助项目(20803035)
江苏省自然科学基金资助项目(BK200718)