Comparison of LiVPO4F to Li4Ti5O12 as Anode Materials for Lithium-Ion Batteries
Comparison of LiVPO4F to Li4Ti5O12 as Anode Materials for Lithium-Ion Batteries
复制标题
LiVPO4F与Li4Ti5O12作为锂离子电池负极材料的比较
DOI：
10.1021/am402132u
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发表时间：
2013-09-11
影响因子：
9.5
通讯作者：
Shu, Jie
中科院分区：
文献类型：
--
作者：
Ma, Rui;Shao, Lianyi;Shu, Jie
本文报道了LiVPO4F和Li4Ti5O12，2作为锂离子电池负极材料的比较。结合粉末X射线衍射、扫描电子显微镜、高分辨率透射电子显微镜、恒电流放电/充电测试和原位X射线衍射技术，对V-3+/V2+/V+氧化还原对LiVPO4F和Ti4/Ti3+氧化还原对Li4Ti5O12在1.0-3.0V和0.0-3.0V循环的插入/提取机理进行了探索和比较。电化学结果表明，LiVPO4F和Li4Ti5O12在1.0-3.0V循环时都是无固相界面材料。另外，LiVPO4F和Li4Ti5O12的电化学性能测试表明，在0.0-3.0V循环的样品比在1.0-3.0V循环的样品具有更高的容量，但循环性能较差。在相同的电化学电位窗口下，Li4Ti5O12，2的性能远远优于LiVPO4F。特别是Li4Ti5O12 012在1.0-3.0 Visa中循环20次后的容量保持率高达98.2%。相比之下，Li4Ti5012由于其高的工作电位、结构的零应变特性以及优异的循环稳定性和倍率性能，有望成为候选的负极材料。
In this paper, we reported on a comparison of LiVPO4F to Li4Ti5O12,2 as anode materials for lithium-ion batteries. Combined with powder X-ray diffraction, scanning electron microscopy, high-resolution transmission electron microscopy, galvanostatic discharge/charge tests and in situ X-ray diffraction technologies, we explore and compare the insertion/extraction mechanisms of LiVPO4F based on the V-3+/V2+/V+ redox couples and Li4Ti5O12 based on the Ti-4/Ti3+ redox couple cycled in 1.0-3.0 V and 0.0-3.0 V. The electrochemical results indicate that both LiVPO4F and Li4Ti5O12 are solid electrolyte interphase free materials in 1.0-3.0 V. The insertion/extraction mechanisms of LiVPO4F and Li4Ti5O12 are similar with each other in 1.0-3.0 V as proved by in situ X-ray diffraction. It also demonstrates that both samples possess stable structure in 0.0-3.0 V. Additionally, the electrochemical performance tests of LiVPO4F and Li4Ti5O12 indicate that both samples cycled in 0.0-3.0 V exhibit much higher capacities than those cycled in 1.0-3.0 V but display worse cycle performance. The performance of Li4Ti5O12,2 far exceeds that of LiVPO4F in the same electrochemical potential window. In particular, the capacity retention of Li4Ti5O12 012 cycled in 1.0-3.0 Visas high as 98.2% after 20 cycles. By contrast, Li4Ti5012 is expected to be a candidate anode material considering its high working potential, structural zero-strain property, and excellent cycle stability and rate performance.