Hostname: page-component-78c5997874-4rdpn Total loading time: 0 Render date: 2024-11-14T07:25:00.861Z Has data issue: false hasContentIssue false
  • English
  • Français

Crystal structure and electrochemical properties of LiFe1−xZnxPO4 (x ≤ 1.0)

Published online by Cambridge University Press:  05 March 2012

Yanming Zhao ,
Ling Chen ,
Xiren Chen ,
Quan Kuang  and
Youzhong Dong
Yanming Zhao
Affiliation:
School of Physics, South China University of Technology, Guangzhou 510640, China
Ling Chen
Affiliation:
School of Physics, South China University of Technology, Guangzhou 510640, China
Xiren Chen*
Affiliation:
School of Physics, South China University of Technology, Guangzhou 510640, China
Quan Kuang
Affiliation:
School of Physics, South China University of Technology, Guangzhou 510640, China
Youzhong Dong
Affiliation:
School of Physics, South China University of Technology, Guangzhou 510640, China
*
a)Author to whom correspondence should be addressed. Electronic mail: [email protected]
Get access Rights & Permissions [Opens in a new window]

Abstract

A series of LiFe1−xZnxPO4 (0.0 ≤ x ≤ 1.0) compounds were prepared by solid-state reaction. Effects of the substitution of Zn for Fe on crystal structure and electrochemical properties of LiFe1−xZnxPO4 were investigated. The results show that single-phase regions of LiFe1−xZnxPO4 with orthorhombic (space group Pmna) and monoclinic (Cc) structures were found for the compounds with low Zn (or high Fe) contents of 0.0 ≤ x ≤ 0.30 and high Zn (or low Fe) contents of 0.90 ≤ x ≤ 1.0, respectively. The LiFe1−xZnxPO4 compounds with medium Zn (or Fe) contents of 0.35 ≤ x ≤ 0.80 are two-phase mixtures containing both the orthorhombic and the monoclinic phases. Systematic variations of unit-cell parameters a, b, c, and volume V with the Zn content determined by X-ray diffraction have also been obtained. Our electrochemical study show that the conductivity of LiFe1−xZnxPO4 increases by almost 2 orders of magnitude from 2.13 × 10−9 to 1.27 × 10−7 Scm−1 as the Zn content increasing from x = 0 to 0.3. The initial specific capacity decreases and the cycle performance increase with increasing Zn-doping content in the four orthorhombic LiFe1−xZnxPO4 compounds. Among the four LiFe1−xZnxPO4 compounds, LiFe0.8Zn0.2PO4 has the highest capacity retentions after 6 to 20 cycles and the capacity retention is 93.7% after 20 cycles, even though the initial discharge specific capacity of LiFe0.8Zn0.2PO4 is lower than those of LiFeZnPO4 and LiFe0.9Zn0.1PO4. LiFe0.7Zn0.3PO4 has the highest capacity retention of 97% after 20 cycles.

Keywords

LiFe1−xZnxPO4unit-cell parameterselectrochemical performancelithium batteries
Type
Technical Articles
Information
Powder Diffraction , Volume 26 , Issue 3 , September 2011 , pp. 238 - 243
Copyright
Copyright © Cambridge University Press 2011

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Barker, J., Saidi, M. Y., and Swoyer, J. L. (2003) “Lithium iron(II) phosphor-olivines prepared by a novel carbothermal reduction method,” Electrochem. Solid-State Lett. 6, A53–A55. 10.1149/1.1544211CrossRefGoogle Scholar
Bu, X.-H., Gier, T. E., and Stucky, G. D. (1998). “A new polymorph of Lithium Zinc Phosphate with the cristobalite-type framework topology,” J. Solid State Chem. 138, 126–130. 10.1006/jssc.1998.7762CrossRefGoogle Scholar
Bu, X.-H., Gier, T. E., and Stucky, G. D. (1996). “A new form of lithium zinc phosphate with an ordered phenakite structure, LiZnPO4,” Acta Crystallogr. Sect. C: Cryst. Struct. Commun. 52, 1601–1603. 10.1107/S0108270195015940CrossRefGoogle Scholar
Carvajal, J. R (1990). “FullProf: A program for rietveld refinement and pattern matching analysis,” Abstracts of the Satellite Meeting on Powder Diffraction of the XV Congress of the IUCr, Toulouse, France, p. 127.Google Scholar
Chung, S. Y., Bloking, J. T., and Chiang, Y. M. (2002). “Electronically conductive phospho-olivines as lithium storage electrodes,” Nat. Mater. 1, 123–128. 10.1038/nmat732CrossRefGoogle ScholarPubMed
Delacourt, C., Wurm, C., Laffont, L., Leriche, J. B., and Masquelier, C. (2006). “Electrochemical and electrical properties of Nb- and/or C-containing LiFePO4 composites,” Solid State Ionics. 177, 333–341. 10.1016/j.ssi.2005.11.003CrossRefGoogle Scholar
Doeff, M. M., Hu, Y., Mclarnon, F., and Kostecki, R. (2003). “Effect of surface carbon structure on the electrochemical performance of LiFePO4,” Electrochem. Solid-State Lett. 6, A207–A209. 10.1149/1.1601372CrossRefGoogle Scholar
Elammari, L. and Elouadi, B. (1989). “Structure of alpha-LiZnPO4” Acta Crystallogr. Sect. C: Cryst. Struct. Commun. 45, 1864–1867. 10.1107/S0108270189003094CrossRefGoogle Scholar
Elfakir, A., Souron, J. P., Robert, F., and Quarton, M. (1989). “Structure crystalline de l’orthophosphate LiZnPO4,” C. R. Acad. Sci. Ser. II: Mec., Phys., Chim., Sci. Terre Univers 309, 199–203.Google Scholar
Franger, S., Cras, F. L., Bourbon, C., and Rouault, H. (2002). “LiFePO4 synthesis routes for enhanced electrochemical performance,” Electrochem. Solid-State Lett. 5, A231–A233. 10.1149/1.1506962CrossRefGoogle Scholar
Harrison, W. T. A., Gier, T. E., Nicol, J. M., and Stucky, G. D. (1995). “Tetrahedral-framework Lithium Zinc Phosphate phases: Location of light-atom positions in LiZnPO4•H2O by powder neutron diffraction and structure determination of LiZnPO4 by ab initio Methods,” J. Solid State Chem. 114, 249–257. 10.1006/jssc.1995.1036CrossRefGoogle Scholar
Herle, P. S., Ellis, B., Coombs, N., and Nazar, L. F. (2004). “Nano-network electronic conduction in iron and nickel olivine phosphates,” Nat. Mater. 3, 147–152. 10.1038/nmat1063CrossRefGoogle ScholarPubMed
Hong, J., Wang, C. S., and Kasavajjula, U. (2006). “Kinetic behavior of LiFeMgPO4 cathode material for Li-ion batteries,” J. Power Sources 162, 1289–1296. 10.1016/j.jpowsour.2006.08.004CrossRefGoogle Scholar
Huang, H., Yin, S. C., and Nazar, L. F. (2001). “Approaching theoretical capacity of LiFeMgPO4 at room temperature at high rates,” Electrochem. Solid-State Lett. 4, A170–A172. 10.1149/1.1396695CrossRefGoogle Scholar
Jensen, T. R., Norby, P., Stein, P. C., and Bell, A. M. T. (1995). “Preparation, structure determination and thermal transformation of a new Lithium Zinc Phosphate, δ1-LiZnPO4,” J. Solid State Chem. 117, 39–47. 10.1006/jssc.1995.1244CrossRefGoogle Scholar
Kabalov, Y. K., Simonov, M. A., Ivanov, V. I., Mel’nikov, O. K., and Belov, N. V. (1973). “The crystal structure of Li(Fe,Zn)(PO4),” Dokl. Acad. Nauk SSSR 208, 1346.Google Scholar
Li, X. L., Kang, F. Y., Bai, X. D., and Shen, W. C. (2007). “A novel network composite cathode of LiFePO4/multiwalled carbon nanotubes with high rate capability for lithium ion batteries,” Electrochem. Commun. 9, 663–666. 10.1016/j.elecom.2006.10.050CrossRefGoogle Scholar
Morcrette, M., Wurm, C., and Masquelier, C. (2002). “On the way to the optimization of Li3Fe2(PO4)3 positive electrode materials,” Solid State Sci. 4, 239–246. 10.1016/S1293-2558(01)01235-3CrossRefGoogle Scholar
Morgan, D., Ceder, G.., Saidi, M. Y., Barker, J., Swoyer, J., Huang, H., and Adamson, G. (2003). “Experimental and computational study of the structure and electrochemical properties of monoclinic LixM2(PO4)3 compounds,” J. Power Sources 119, 755–759. 10.1016/S0378-7753(03)00216-7CrossRefGoogle Scholar
Padhi, A. K., Nanjundaswamy, K. S., and Goodenough, J. B. (1997). “Phospho-olivines as positive-electrode materials for rechargeable lithium batteries,” J. Electrochem. Soc. 144, 1188–1194. 10.1149/1.1837571CrossRefGoogle Scholar
Park, K. S., Son, J. T., Chung, H. T., Kim, S. J., Lee, C. H., Kang, K. T., and Kim, H. G. (2004) “Surface modification by silver coating for improving electrochemical properties of LiFePO4,” Solid State Commun. 129, 311–314. 10.1016/j.ssc.2003.10.015CrossRefGoogle Scholar
Penazzi, N., Arrabit, M., Piana, M., Bodoardo, S., Panero, S., and Amadei, I. (2004). “Mixed lithium phosphates as cathode materials for Li-ion cells,” J Eur. Ceram. Soc. 24(6), 1381–1384. 10.1016/S0955-2219(03)00568-5CrossRefGoogle Scholar
Rietveld, H. M. (1967) “Line profiles of neutron powder-diffraction peaks for structure refinement,” Acta Crystallogr. 22, 151–152. 10.1107/S0365110X67000234CrossRefGoogle Scholar
Rietveld, H. M. (1969). “A profile refinement method for nuclear and magnetic structures,” J. Appl. Crystallogr. 2, 65–71. 10.1107/S0021889869006558CrossRefGoogle Scholar
Shannon, R. D. (1976). “Revised effective ionic radii and systematic studies of interatomic distances in halides and chalcogenides,” Acta Crystallogr. Sect. A: Found. Crystallogr. 32(5), 751–767. 10.1107/S0567739476001551CrossRefGoogle Scholar
Shenouda, A. Y. and Liu, H. K. (2009) “Studies on electrochemical behaviour of zinc-doped LiFePO4 for lithium battery positive electrode” J. Alloys Compd. 477, 498–503. 10.1016/j.jallcom.2008.10.077CrossRefGoogle Scholar
Sun, C. S., Zhou, Z., Xu, Z. G., Wang, D. G., Wei, J.P., Bian, X. K., and Yan, J. (2009). “Improved high-rate charge/discharge performances of LiFePO4/C via V-doping,” J. Power Sources, 193, 841–845. 10.1016/j.jpowsour.2009.03.061CrossRefGoogle Scholar
Torres-Treviño, G., and West, A. R. (1986) “Compound formation, crystal chemistry, and phase equilibria in the system Li3PO4---Zn3(PO4)2” J. Solid State Chem. 61, 56–66. 10.1016/0022-4596(86)90006-XCrossRefGoogle Scholar
Wang, G., Cheng, Y., Yan, M. M., and Jiang, Z. Y. (2007). “Li0.99Ti0.01FePO4/C composite as cathode material for lithium ion battery,” J. Solid State Electrochem. 11, 457–462. 10.1007/s10008-006-0173-4CrossRefGoogle Scholar
Wang, G. X., Bewlay, S., Yao, J., Ahn, J. H., Dou, S. X and Liu, H. K. (2004). “Characterization of LiMxFe1–xPO4 (M = Mg, Zr, Ti) cathode materials prepared by the sol-gel method,” Electrochem. Solid-State Lett. 7, A503–A506. 10.1149/1.1819867CrossRefGoogle Scholar
Wagemaker, M., Ellis, B. L., Lutzenkichen-Hecht, D., Mulder, F. M., and Nazar, L. F. (2008). “Proof of Supervalent Doping in Olivine LiFePO4,” Chem. Mater. 20, 6313–6315. 10.1021/cm801781kCrossRefGoogle Scholar
Werner, P. E. (1976) “On the determination of unit-cell dimensions from inaccurate powder diffraction data,” J. Appl. Crystallogr. 9, 216–219. 10.1107/S0021889876010996CrossRefGoogle Scholar
Zhao, Y. M., Liang, J. K., Rao, G. H., Guo, R. Q., and Tang, W. H. (1996). “Crystallographic and magnetic properties of NdCo11-xSix compounds,” J. Appl. Phys. 80, 5200–5204. 10.1063/1.363503CrossRefGoogle Scholar