中文关键词:正极材料锰酸锂包覆锂离子电池 英文关键词:Cathode materialsLi₄Mn₅O₁₂CoatingLithium-ion battery 基金项目:

作者	单位
师林涛	上海大学材料科学与工程学院 上海 200444
崔洪福	上海大学材料科学与工程学院 上海 200444
徐超祥	上海大学材料科学与工程学院 上海 200444
喻春鹏	上海大学材料科学与工程学院 上海 200444

摘要点击次数:795 全文下载次数:0 中文摘要: LiNi_1/3Mn_1/3Co_1/3O₂具有很高的理论比容量，但是三元正极材料在高电压下长循环时，其表面结构发生较大的衰退，导致电池的循环性能和倍率性能变差。本文采用耐高电压且结构稳定的富锂尖晶石Li₄Mn₅O₁₂包覆LiNi_1/3Mn_1/3Co_1/3O₂可以有效改善材料的电化学性能。通过XRD、SEM、XPS和TEM等手段对包覆后的材料进行分析，证实了在LiNi_1/3Mn_1/3Co_1/3O₂的表面形成了10nm厚的均匀Li₄Mn₅O₁₂的包覆层；在循环100圈后，包覆后的LiNi_1/3Mn_1/3Co_1/3O₂仍具有179.5mAh/g的放电比容量和88.6%容量保持率，明显高于未包覆的LiNi_1/3Mn_1/3Co_1/3O₂的78.3%容量保持率。因此，利用富锂尖晶石Li₄Mn₅O₁₂包覆LiNi_1/3Mn_1/3Co_1/3O₂为实现更高能量密度的锂离子电池提供了新的途径。 英文摘要: LiNi_1/3Mn_1/3Co_1/3O₂ has high theoretical specific capacity, but the surface structure of the cathode material greatly decays at high charging voltage, which leads to the deterioration of cycle performance and rate performance for batteries. In this paper it was reported that LiNi_1/3Mn_1/3Co_1/3O₂ coated with lithium-rich spinel Li₄Mn₅O₁₂ can effectively improve the electrochemical performance. XRD, SEM, XPS and TEM were used to analyze the cathode material. It was confirmed that Li₄Mn₅O₁₂uniformly formed a coating layer of 10 nm thick on the surface of LiNi_1/3Mn_1/3Co_1/3O₂. LiNi_1/3Mn_1/3Co_1/3O₂@Li₄Mn₅O₁₂ has a high discharge capacity of 179.5 mAh/g, and the capacity retention rate is 88.6% after 100 cycles, which is significantly higher than that of LiNi_1/3Mn_1/3Co_1/3O₂(78.3%). Therefore, the coating of LiNi_1/3Mn_1/3Co_1/3O₂ with lithium-rich spinel Li₄Mn₅O₁₂ provides a new way to achieve a high energy density of lithium-ion batteries. 查看全文查看/发表评论下载PDF阅读器 相关附件：版权转让声明书附件1 -->