The preparation and characterization of iron fluorides polymorphs FeF{sub 3}·0.33H{sub 2}O and β-FeF{sub 3}∙3H{sub 2}O as cathode materials for lithium-ion batteries

Journal Article · Wed Apr 15 00:00:00 EDT 2015 · Materials Research Bulletin

DOI:https://doi.org/10.1016/J.MATERRESBULL.2014.12.061· OSTI ID:22475730

Chen, Chao; Xu, Xiaoping; Chen, Shu; Zheng, Bin; Shui, Miao; Xu, Lingxia; Zheng, Weidong; Shu, Jie; Cheng, Liangliang; Feng, Lin; Ren, Yuanlong

Graphical abstract: Better rate capability and cycling performance were observed for β-FeF{sub 3}·3H{sub 2}O/C prepared by mechano-chemical synthesis. - Highlights: • A novel mechano-chemical preparation method. • The use of NH{sub 4}F as starting material. • Better electro-chemical performance in the case of β-FeF{sub 3}·3H{sub 2}O/C. - Abstract: Two kinds of iron fluorides, FeF{sub 3}·0.33H{sub 2}O and β-FeF{sub 3}∙3H{sub 2}O, have been synthesized by different chemical routes using Fe(NO{sub 3}){sub 3}·9H{sub 2}O and NH{sub 4}F as precursors and investigated as cathode materials for secondary lithium batteries. β-FeF{sub 3}·3H{sub 2}O was obtained via a mechano-chemical process and FeF{sub 3}·0.33H{sub 2}O was obtained by a precipitation reaction from ethanol solution. To further improve their electrochemical properties, a ball milling process with carbon has been used to form composites. The fluorides were characterized by X-ray diffraction (XRD), thermal analysis, FTIR spectroscopy, galvanostatic charge/discharge and cyclic voltammetry measurements. The results showed that the as-prepared β-FeF{sub 3}·3H{sub 2}O/C exhibited better rate performance and cycling stability. It exhibited an initial discharge capacity of 199.6 mA h g{sup −1} at a current density of 20 mA g{sup −1} in a voltage range of 1.8–4.5 V and still reserved a discharge capacity of about 146.5 mA h g{sup −1} after 10 cycles. Only a capacity loss of 15 mA h g{sup −1} and 7 mA h g{sup −1} was observed when the current density was at 40 mA g{sup −1} and 80 mA g{sup −1}, respectively.

• OSTI ID: 22475730
• Journal Information: Materials Research Bulletin, Vol. 64; Other Information: Copyright (c) 2014 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA); ISSN 0025-5408
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
AMMONIUM FLUORIDES
CAPACITY
CHEMICAL PREPARATION
CURRENT DENSITY
ELECTRIC BATTERIES
ELECTROCHEMISTRY
INFRARED SPECTRA
IRON FLUORIDES
IRON NITRATES
LITHIUM IONS
PERFORMANCE
SPECTROSCOPY
THERMAL ANALYSIS
VOLTAMETRY
X-RAY DIFFRACTION