Co3+-modified Surface of LiMn2O4 Spinel for its Improvement of Electrochemical Properties

Abstract

Abstract: Cobalt was used to modify the surface of spinel LiMn2O4 by a solution technique to produce Co3+-modified surface material (COMSM). Cobalt was only doped into the surface of LiMn2O4 spinel. XPS(X-ray photoelectron spectroscopy) analysis confirms the valence state of Co3+. COMSM has stable spinel structure and can prevent active materials from the corrosion of electrolyte. The ICP(inductively coupled plasma) determination of the spinel dissolution in electrolyte showed the content of Mn dissolved from COMSM was smaller than that from the pure spinel. AC impedance patterns show that the charge-transfer resistance (Rct) for COMSM is smaller than that for pure spinel. The particles of COMSM are bigger in size than those of pure spinel according to the micrographs of SEM(scanning electron microscopy). The determinations of the electrochemical characterization show that COMSM has both good cycling performance and high initial capacity of 124.1 mA/h at an average capacity loss of 0.19 mAh/g per cycle.

Key words: Lithium ion batteries, LiMn2O4, Cation doping, Coating

Zishan ZHENG, Zilong TANG, Zhongtai ZHANG, Junbiao LU, Wanci SHEN. Co3+-modified Surface of LiMn2O4 Spinel for its Improvement of Electrochemical Properties[J]. J Mater Sci Technol, 2003, 19(04): 359-362.

References

[1] Yongyao XIA, Yunhong ZHOU and M.Yoshio: J.Electrochem.Soc., 1997, 144, 2593．
[2] R.J.Gummow, A.De Kock and M.M.Thackeray: Solid State Ionics, 1994, 69, 59．
[3] Guohua Li, H.Ikuta, T.Uchida and M.Wakihara: J. Electrochem. Soc., 1996, 143, 178．
[4] D.H.Jang, Y.J Shin and S.M.Oh: J. Electrochem. Soc., 1997,144, 2593．
[5] H.Kanoh, Q.Feng, T.Hirotsu and K.Ooi: J. Electrochem. Soc.,1996, 143, 2610．
[6] M.M.Thackeray Y.Shao-Horn and A.Kahaian: J. Electrochem.Solid State Lett., 1998, 1, 7．
[7] J.M.Tarascon, W.R.McKinnon, F.Coowar, T.N.Bowmer,G.Amatucci and D.Guyomard: J. Electrochem. Soc., 1994,141, 1421．
[8] S.J.Wen, T.J.Richardson, L.Ma, K.A.Striebel, P.N.Ross, Jr.and E.J.Cairns: J. Electrochem. Soc., 1996, 143, L136．
[9] D.H.Jang, J.Y.Shin and S.M.Oh: Solid State Ionics, 1996, 143,L136．
[10] P.Arora, B.N.Popov and R.E.White: J. Electrochem. Soc.,1998, 145, 807．
[11] M. Wohlfahrt-Mehrens, A. Butz and R. Oesten: J. Power Sources, 1997, 68, 582．
[12] A.D.Robertson, S.H.Lu and W.F.Howard: J. Electrochem.Soc., 1997, 144, 3500．
[13] J.M.Tarascon, E.Wang and F.K.Shokoohi: J. Electrochem.Soc., 1991, 138, 2859．
[14] D.Song, H.Ikuta, T.Uchida and M.Wakihara: Solid State Ionics, 1999, 117, 151．
[15] G.G.Amatucci, A.Blyr, C.Sigala, P.Alfonse and J.M.Tarascon:Solid State Ionics, 1997, 104, 13．
[16] Zishan ZHENG, Zilong TANG, Zhongtai ZHANG, Wanci SHEN and Yuanhua LIN: Solid State Ionics, 2002, 148(3-4) ,317．
[17] S.H.Chang, K.S.Ryu, K.M.Kim, I.K.Kim and S.G.Kang: J.Power Sources, 1999, 84, 134．
[18] J.M.Amarilla, J.L.M de Vidales and R.M.ROjas: Solid State Ionics, 2000, 127, 73．
[19] Y.K.Sun, K.H.Lee, S.I.Moon and I.H.Oh: Solid State Ionics,1998, 112, 237．
[20] J.F.Moulder, W.F.Stickle, P.E.Scobol and K.D.Bomben:Handbook of X-ray Photoelectron Spectroscopy,Published by Perkin-Elmer Corporation, USA, 1992．
[21] Zishan ZHENG, Zilong TANG, Zhongtai ZHANG and Wanci SHEN: J. Inorg. Mater., 2002, 17, 999． (in Chinese)
[22] S.C.Park, Y.S.Han, Y.S.Kang P.S.Lee, S.Ahn, H.M.Lee and J.Y.Lee: J. Electrochem. Soc., 2001, 148, A680．
[23] J.Cho, G.B.Kim, H.S.Lim, C.S.Kim and S.I.Yoo: Electrochem.Solid State Lett., 1999, 2(12) , 607．