气候变化领域集成服务门户(CCPortal): Gradient-morph LiCoO2single crystals with stabilized energy density above 3400 W h L-1

CCPortal

DOI	10.1039/d0ee00231c
	Gradient-morph LiCoO2single crystals with stabilized energy density above 3400 W h L-1
	Zhu Z.; Yu D.; Shi Z.; Gao R.; Xiao X.; Waluyo I.; Ge M.; Dong Y.; Xue W.; Xu G.; Lee W.-K.; Hunt A.; Li J.
发表日期	2020
ISSN	17545692
起始页码	1865
结束页码	1878
卷号	13 期号:6
英文摘要	The cycling stability of LiCoO2 under high voltages (>4.5 V) was plagued by hybrid anion- and cation-redox (HACR) induced oxygen escape and uncontrolled phase collapse. With DEMS and in situ XANES mapping at the NSLS-II, we demonstrate that oxygen escape triggers irreversible transformations into "bad"surface phases that rapidly propagate inward. Enabling HACR but stopping global oxygen migration is key to a stable high-energy cathode. Therefore, we developed ∼10 μm single crystals with LiCoO2 in the bulk smoothly transitioning to Co-free LiMn0.75Ni0.25O2 at the surface. By means of initial electrochemical formation, a semi-coherent LiMn1.5Ni0.5O4 spinel-like shell was established in operando with little oxygen loss to integrally wrap the LiCoO2 bulk. Then we obtained gradient-morph LiCoO2 single crystals to prevent the percolating migration of oxygen out of the particle and achieved enhanced HACR reversibility at high voltages. The gradient-morph HACR cathode undergoes substantially stabilized cycling when charged to above 4.6 V, and hence a stable cyclic volumetric energy density of >3400 W h L-1 has been achieved in a pouch full-cell coupled with a commercial graphite anode and lean electrolyte (2 g A h-1), exhibiting up to 2906 W h L-1 even after 300 cycles. © The Royal Society of Chemistry.
英文关键词	Cathodes; Cobalt compounds; Electrolytes; Manganese compounds; Nickel compounds; Oxygen; Single crystals; Cycling stability; Electrochemical formation; Energy density; Graphite anode; Oxygen migration; Phase collapse; Surface phasis; Volumetric energy densities; Lithium compounds
语种	英语
来源期刊	Energy & Environmental Science
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/189631
作者单位	Department of Nuclear Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, United States; National Synchrotron Light Source II, Brookhaven National Laboratory, Upton, NY 11973, United States
推荐引用方式 GB/T 7714	Zhu Z.,Yu D.,Shi Z.,et al. Gradient-morph LiCoO2single crystals with stabilized energy density above 3400 W h L-1[J],2020,13(6).
APA	Zhu Z..,Yu D..,Shi Z..,Gao R..,Xiao X..,...&Li J..(2020).Gradient-morph LiCoO2single crystals with stabilized energy density above 3400 W h L-1.Energy & Environmental Science,13(6).
MLA	Zhu Z.,et al."Gradient-morph LiCoO2single crystals with stabilized energy density above 3400 W h L-1".Energy & Environmental Science 13.6(2020).