共 21 条
Energy storage in composites of a redox couple host and a lithium ion host
被引:46
作者:
Kim, Sung-Wook
[1
]
Nam, Kyung-Wan
[2
]
Seo, Dong-Hwa
[1
]
Hong, Jihyun
[1
]
Kim, Hyungsub
[1
]
Gwon, Hyeokjo
[3
]
Kang, Kisuk
[1
]
机构:
[1] Seoul Natl Univ, Dept Mat Sci & Engn, Seoul 151742, South Korea
[2] Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA
[3] Korea Adv Inst Sci & Technol, Dept Mat Sci & Engn, Taejon 305701, South Korea
来源:
关键词:
Energy storage;
Li -ion batteries;
Electrochemistry;
Positive electrode;
Composite materials;
CATHODE MATERIAL;
HIGH-POWER;
NANOCOMPOSITE;
FLUORIDE;
D O I:
10.1016/j.nantod.2012.04.004
中图分类号:
O6 [化学];
学科分类号:
0703 ;
摘要:
The quest for new positive electrodes for rechargeable lithium-ion batteries has been escalating in recent years. Until now, candidates of positive electrode were limited to crystals that contain both redox-active element (usually transition-metal) and lithium ion in the open framework with few exceptions. Here, we demonstrate lithium-free compounds, a material with little activity by itself, can be activated electrochemically by addition of LiF after the first charging. This general strategy is exemplified in various lithium-free iron compounds. Reversible lithium ion extraction and reinsertion take place for Fe2+F2, Fe2+ SO4, and Fe22+P2O7, when blended with LiF in nanoscale, in which a simultaneous valence change of Fe2+/3+ occurs above 3 V. FeF2-LiF could deliver 190 mAh g(-1) (similar to 3.53 V) at 50 mA g(-1) which is even higher energy density than that crystalline LiFePO4 can offer. Various combinations of blending are possible using this approach, which can bring a new branch of material group for positive electrodes in lithium-ion batteries. (C) 2012 Elsevier Ltd. All rights reserved.
引用
收藏
页码:168 / 173
页数:6
相关论文