物理化学学报 >> 2014, Vol. 30 >> Issue (4): 669-676.doi: 10.3866/PKU.WHXB201402102

电化学和新能源 上一篇    下一篇

新型复合共沉淀法制备高能量/高功率型锂离子二次电池用5 V正极材料LiNi0.5Mn1.5O4及其电化学性能

朱智1, 其鲁1, 李卫2,3, 廖细英3   

  1. 1 北京大学化学与分子工程学院, 北京100190;
    2 北京科技大学材料科学与工程学院, 北京100083;
    3 思伊纳化学科技(北京)有限公司, 北京100094
  • 收稿日期:2013-11-19 修回日期:2014-01-26 发布日期:2014-03-31
  • 通讯作者: 其鲁 E-mail:gilu297542@pku.edu.cn

Preparation and Electrochemical Performance of 5 V LiNi0.5Mn1.5O4 Cathode Material by the Composite Co-Precipitation Method for High Energy/High Power Lithium Ion Secondary Batteries

ZHU Zhi1, QI Lu1, LI Wei2,3, LIAO Xi-Ying3   

  1. 1 College of Chemistry and Molecular Engineering, Peking University, Beijing 100190, P. R. China;
    2 School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083;
    3 SYN Chemicals & Technology (Beijing) Co. Ltd., Beijing 100094, P. R. China
  • Received:2013-11-19 Revised:2014-01-26 Published:2014-03-31
  • Contact: QI Lu E-mail:gilu297542@pku.edu.cn

摘要:

在传统固相法的基础上开发了新型复合共沉淀法制备LiNi0.5Mn1.5O4材料. 新型复合共沉淀法采用(NH42CO3和(NH42C2O4共同作为沉淀剂,通过控制共沉淀反应条件,得到了具有均匀球形形貌的沉淀物颗粒. 再通过与饱和氢氧化锂溶液的水热反应及高温反应,最终制备出具有球形次级形貌和纯相尖晶石结构的LiNi0.5Mn1.5O4材料. 电化学测试表明,制备的LiNi0.5Mn1.5O4具有优异的电化学性能,其初始容量达到了141.4mAh·g-1. 在0.3C、1C和3C倍率下经过200 次循环后的容量分别为136.0 mAh·g-1 (96.3%)、128.6 mAh·g-1(94.4%)和113.9 mAh·g-1 (91.1%). 通过高温反应及特殊的冷却处理,LiNi0.5Mn1.5O4在4.0 V低压区平台的容量损失得到了有效抑制. 更重要的是,通过控制合成过程中的关键步骤,可实现半定量化控制材料结构中的原子有序排布程度,进而得到具有高能量密度和高功率密度的两种LiNi0.5Mn1.5O4材料,其能量密度和功率密度分别达到了648.6 mWh·g-1和7000 mW·g-1以上.

关键词: 锂离子电池, 尖晶石镍锰酸锂, 高能量/高功率, 共沉淀法, 球形次级颗粒

Abstract:

This research developed a novel composite co-precipitation method to prepare high performance LiNi0.5Mn1.5O4 based on a traditional solid-state method. Ammonium oxalate/ammonium carbonate was used as a composite precipitator to deposit Ni/Mn ions. Combined with a facile hydrothermal treatment, stoichiometric LiNi0.5Mn1.5O4 was obtained with a pure spinel structure and spherical hierarchical morphology. Electrochemical measurements indicate that the as-prepared LiNi0.5Mn1.5O4 delivers a high capacity of 141.4 mAh·g-1 and after 200 cycles under 0.3C, 1C, and 3C, the materials retained their capacities up to 96.3%, 94.4%, and 91.1%, respectively. Additionally, the capacity upon exposure to a low voltage of 4.0 V was efficiently eliminated by heat treatment and by a particular cooling process. Furthermore, the LiNi0.5Mn1.5O4 materials with high energy and high power performances of 648.6 mWh·g-1 and 7000mW·g-1 were obtained because of different cation ordering.

Key words: Lithium ion battery, Spinel lithium nickel magnesium oxide, High energy/high power, Co-precipitation method, Spherical hierarchical morphology

MSC2000: 

  • O646