摘要
本论文采用传统固相法和液相法制备了锂离子二次电池用的具有层状结构的LiNi_(0.7)Co_(0.3)O_2正极材料和LiNi_(0.7)Co_(0.3-x)Al_xO_2材料;利用X射线衍射法、扫描电镜、微电极循环伏安法及恒电流充放电测试等,研究了合成材料的结构和电化学性能,得出以下结论:
1.比较了固相法和液相法制得的LiNi_(0.7)Co_(0.3)O_2正极材料的结构和电化学性能发现,采用液相法更易于制得纯相得LiNi_(0.7)Co_(0.3)O_2固溶体材料,阳离子有序度及充放电容量、循环性能均要优于固相法所得的LiNi_(0.7)Co_(0.3)O_2材料。
2.对不同热处理工艺制得的LiNi_(0.7)Co_(0.3)O_2固溶体的结构及电化学性能进行研究发现,热处理温度越高、烧结时间越长,产物的晶型越趋完整,层状结构越明显,但电化学性能并不一定好;对固相法而言,800℃附近热处理20小时左右为比较合适的工艺;对液相法而言,考虑到成本和生产效率,在750℃附近热处理20小时左右为宜。
3.对比研究了三种液相法所制备LiNi_(0.7)Co_(0.3)O_2正极材料的结构和电化学性能发现,以均匀沉淀法所制样品电化学性能最好;以金属镍粉为原料所制样品晶体结构虽好,但放电容量偏低,这可能与金属镍粉的活性有关;而共沉淀法所得样品性能虽好,但工艺较为复杂,pH值不易控制,加大了工业生产的难度。
4.固相法制备的LiNi_(0.7)Co_(0.3-x)Al_xO_2样品具有与层状结构LiNiO_2
摘要
相同的晶体结构,属于三方晶系六方晶胞。研究发现,铿镍钻化合
物中掺铝虽可稳定化合物的结构,但掺入量不宜太多,认为掺入量x
应小于0.10;800℃是最合适的合成温度,这个温度下制备的样品的
I、。。3,/l、,。4,的比值比较大,阳离子有序度高,结构稳定,但电化学
性能尚未得到显著提高,有待于进一步深入的研究。
Layered structral LiNio.7Coo.3O2 positive materials and LiNio.7Coo.3=xAlxO2 materials for rechargable lithium-ion batteries were prepared by traditional solid phase and liquid methods. Measurements such as XRD. SEM. microelectrode cyclic voltammetry. galvamostative charge/discharge test were introduced to study the crystal structures and electrochemical performances of the materials prepared. We arrived the conclusions as following:
1 .After comparision of the structures and electromechical properties of LiNi0.7Coo.3O2 positive materials prepared by solid and liquid phase methods espectively, we came to realize that, it was more easier to get pure LiNio.7Co0.33O2 materials by liquid methods, and the charge/discharge capacity . cyclic performances are superial to that materials prepared by solid phase methods.
2.Comparing the structrues and electrochemical properties of LiNio.7Co0.33O2 solid solutions under different heat treatment processes, we could see that, with the rising of the sintering temperature and the extension of the sintering period, the crystal of the products appeared more and more perfect, but the electrochemical performances were't determined to be good. As to solid phase method, 800 癈 for about 20 hours was the optimum heat treatment process, and about 20 hours under
750 for liquid methods considering of the cost and efficiency.
3. The structrues and electrochemical properties of LiNi0.7.7Co0.3O2 positive materials prepared by three kinds of liquid methods were studied, and samples prepared by homogeneous precipitation were proved to have the best electrochemical properties. Samples introducing nickel powder to be Ni source had perfect crystal structures, but the discharge capacity was far from satisfaction. Materials prepared by simultaneous precipitation had excellent combination properties, while the technology was more complex than others, and it was not convinent to control the pH value, which would bring inconvinences to industrial process.
4. LiNio.7Co.3-AlO2 prepared by solid phase method had the same crystal structures with layered LiNiO. It was revealed that doping Al to LiNioCooO compounds will stablize the layered structure, but the value of 'x' should be less than 0.10. 80C was the optimum synthesis temperature, and materials generated under the condition had larger ratio value of I and higher degree of order of cation, which leading to stable structures. But the electrochemical properties didn't have dramatic elevation, and further investigations were expected.
引文
[1].曾祖亮,锂离子正极材料技术进展,《四川有色金属》2000年第1期:37-42
[2].胡晓红,嵌锂正极材料的制备及其应用,武汉大学博士学位论文,1998
[3]. Armand M., in materials for advance batteries, D.W. Murphy, Broodhead J. and Steele B.C.H. editors, P145, Plenum press, New York(1980)
[4]. Semkov K.W. and Sammels A.F. Secondary solid-state SPE cells. J.Electrochem. Soc., 1987,134:766
[5]. D.W.Murphy and J.N.Carides, Equilibrium properties of lithium/niobium selenide, nonaqueous secondary cells, J.Electrochem.Soc. 1979, 126:349
[6]. Auborn J.J. and Barberio Y.L., Lithium intercalation cells without metallic lithium MoO_2/LiCoO_2 and WO_2/LiCoO_2. J.Electrochem.Soc.,1987.134:63
[7].李振垣编《元素化学性质数据手册》,河北人们出版社,1985
[8]. Tsutomu Ohzuku. Lithium Batteries. Chapter 6, Pressed by Elsevier Science BV, the Netherlands, 1994
[9].雷永泉,万群,石永康,新能源材料,天津大学出版社,2000
[10].Mizushima K, Jones P C, Wiseman P J, et al Li_xCoO_2(0 [11].D.W.Murphy and J.N.Carides, EQUILIBRIUM PROPERTIES OF LITHIUM/NIOBIUM SELENIDE, NONAQUEOUS SECONDARY CELLS, J.Electrochem.Soc. 1979,126:349
[12].Mizushima K. et al. Mat. Res. Bull. 1980,15,783
[13].Reimers J.N. et al. J. Electrochem. Soc. 1992,139(8),2091
[14].XIA Xi. Dianchi(Battery Bimonthly), 1998,28(6),251
[15].WU Guo-Liang. et al. Dianchi(Battery Bimonthly), 1998,28(6),258
[16].Gummow. R.J. et al. Mat. Res. Bull. 1992,27,327
[17].Hench. L. L. et al. Chem. Rev.1990,90,33
[18].Liu R M, Yang X H, Wiseman P J, et al Mechanism of Li_(1+x)CoO_2 snthesis and the influence of x values on Performance Proceeding of 12th International Conference on solid State Ionics, 1999(in Press)
[19].Desilvestro J, Haas. O. J.Electrochem. Soc., 1990,137:5C-22C
[20].Arai Hajime, Okada Shegeto, Sakurai Yoji, et al. Solid State
Ionics, 1997,95:275-282
[21].Hirano A, Kanno R, Kawamoto Y, et al. Solid State Ionics, 1995,78:123-131
[22].M.R.Palacn D.Larcher, et al., Low-Temperature Synthesis of LiNiO_2 Reaction mechanism, stability, and electrochemical properties, J. Electrochem. Soc, 197, 144(12):4226-423
[23].高虹,等.锂离子电池正极材料LiNiO_2的制备和研究[J],电源技术,1999,23(增刊):53
[24].Fujita Y, Amine K, Maruta J, et al. LiNi_(1-x)Co_xO_2 prepared at low temperature using β-Ni_(1-x)Co_xOOH and either LiNO_3 or LiOH [J]. J. Power Sources, 1997,68:126-130
125].Delmas C, Saadounne I, Pougier A. The cycling properties of the LiNi_(1-y)Co_yO_2 electrode [J]. J Power Sources, 993,43-44:595-602
[26].Banov B, Bourilkov J, Mladenov M. Cobalt stabilized layered lithium-nickel oxides cathodes in lithium rechargeable cells [J] J Power Sources, 1995,54:268-270
[27].Arai H, Okada S, Sakurai Y, et al. Electrochemical and thermal behavior of LiNi_(1-z)M_zO_2(M=Co、Mn、Ti) [J]. J Electrochem Soc, 1997,144(9): 3117-3125
[28].Zhong Q, Sacken U. Crystal structures and electrochemical properities of LiAl_yNi_(1-y)O_2 solid solution [J]. J Power Sources, 1995,54:221-223
[29].Ohzuku T, Ueda A,Kouguchi M. synthesis and characterization of LiAl_(1/4)Ni_(3/4)O_2(R3m) for lithium-ion (shuttlecock) batteries [J].Electrochem Soc, 1995,143(12):4033-4039
[30].Nishida Y, Nakane K, Satoh T. Synthesis and properties of gallium-doped as the cathode material for lithium secondary batteries [J]. J Power Sources, 1997,68:561-564.
[31].Masaki H, Yasuhiko B, Shuji I,et al. Nonaqueous electrolyte lithium secondary battery [P]. EP:744780
[32].Kumta, Nagesh P, Chang, et al. Cathode materials for lithium-ion secondary cells [P].USP: 6017654
[33].Kubo K, Fujiwara M, Yamada S, et al. Synthesis and electrochemical properties for LiNiO_2 substituted by other elements [J]. J Power Sources, 1997,68:553-557
[34].Biensan, Peres J P, Perton F. Optimised LiNi1-mMmO_2 materials with improved safety and fading [A], The 1999 Joint International Meeting[C], Vol 99:131
[35].El-Farh, L. Massot, M. Lemal, M. Julien, C. Chitra, S. Kalyani, P.
Mohan, T. Gangadharan, R., Physical properties and electrochemical features of lithium nickel-cobalt oxide cathode materials prepared at. moderate temperature , Journal of Electroceramics 1999 3(4): 425-432
[36].Fujitani, S. Fujimoto, H. Nohma, T. Nishio, K, Synthesis and characterization of lithiated nickel based metal oxides as positive electrode materials for lithium ion batteries, Materials Research Society Symposium - Proceedings 575 Apr 5-Apr 8 1999 2000 Materials Research Society p 21-29
[37].Lin, Qin Chen, Ning Ye, Wen, Synthesis and properties of layered oxides LiCo_(1-x)Ni_xO_2 , Journal of Materials Science and Technology 1997 13 (5) : 405-408
[38].Cho, Jaephil Park, Byungwoo, Preparation and electrochemical/thermal properties of LiNi_(0.74)Co_(0.26)O_2 cathode material : Journal of Power Sources 2001 92 (1-2) : 35-39
[39].Zhecheva, E. Stoyanova. Lithium doping of cobalt-nickel spinel oxides at low temperature Materials Science Forum v 152-5 Sep 6-10 1993 1994
[40].Caurant, D. Baffier, N. Garcia, B. Pereira-Ramos, Synthesis by a soft chemistry route and characterization of LiNi_xCo_(1-x)O_2 (0<= x <=1) cathode materials : Solid State Ionics 1996, 91(1-2):45-54
[41].Svegl, F. Orel, B. Preparation of lithiated Co- and Ni-oxide powders and thin films by wet chemistry processing Journal of Sol-Gel Science and Technology 14 2 1999 Kluwer Academic Publishers p 187-201
[42].Julien, C.Letranchant, C.Rangan, S.Lemal, M.Ziolkiewicz,.Layered LiNi_(0.5)Co_(0.5)O_2 cathode materials grown by soft-chemistry via various solution methods , Materials Science and Engineering B: Solid-State Materials for Advanced Technology 2000 76(2): 145-155
[43].Julien, C. E1-Farh, L. Rangan, S. Massot, M. Studies of LiNi_(0.6)Co_(0.4)O_2 cathode material prepared by the citric acid-assisted sol-gel method for lithium batteries Journal of Sol-Gel Science and Technology Kluwer Academic Publishers 1999 15(1): 63-72
[44].Chang, Chun-Chieh Scarr, N. Kumta, P.N. Synthesis and electrochemical characterization of LiMO_2 (M = Ni, Ni_(0.75)Co_(0.25)) for rechargeable lithium ion batteries Solid State Ionics 1998 112(3-4): 329-344
[45].Kubo, K. Arai, S. Yamada, S. Kanda, M., Synthesis and charge-discharge properties of Li_(1+x)Ni_(1-x-y)Co_yO_(2-z)F_z , Journal of Power Sources 81 Sep 1999
Sponsored by: The Electrochemical Societ,; The Electrochemical Society of Japan; International Society of Electrochemistry; Danionics; Eveready Battery Company Inc. Elsevier Sequoia SA : 599-603
[46].Nazri, G.A. Rougier, A. Kia, K.F., Synthesis, characterization, and electrochemical performances of substituted layered transition metal oxides, LiM_(1-y)M prime_yO_2, (M = Ni and Co, M prime = B and Al) , : Materials Research Society Symposium Proceedings v 453 Dec 2-5 1996 1997 Sponsored by: MRS Materials Research Society p 635-646
[47].Ohzuku, Tsutomu Nakura, Kensuke, Aoki, Toshiyuki, Comparative study of solid-state redox reactions of LiCo(1/4)Ni(3/4)O_2 and LiAl(1/4)Ni(3/4)O_2 for lithium-ion batteries , Electrochimica Acta 1999 45(1) : 151-160
[48].Jang, Young-I1 Huang, Biying Wang, Haifeng Maskaly, Garry R. Ceder, Gerbrand Sadoway, Donald R. Chiang, Yet-Ming Liu, Hui Tamura, Hirokazu, Synthesis and characterization of LiAl_yCo(1-y)O_2 and LiAl_yNi(1-y)O_2 , Journal of Power Sources 81 Sep. 1999 Sponsored by: The Electrochemical Societ,; The Electrochemical Society of Japan; International Society of Electrochemistry; Danionics; Eveready Battery Company Inc. Elsevier Sequoia SA : 589-593
[49].Chowdari, B.V.R., Subba Rao, G.V., Chow, S.Y., Cathodic behavior of (Co, Ti, Mg)-doped LiNiO_2, Solid State Ionics 2001 140 (1-2): 55-62
[50].Arai, Hajime ,Tsuda, Masayuki Sakurai, Yoji, Lithium nickelate electrodes with enhanced high-temperature performance and thermal stability , Journal of Power Sources 1999-2000 90 (1) : 76-81
[51].Tsunoda, Michihiko Oshima, Yasunobu Yoshinaga, Masaharu Shirasu, Tetsuo, Prismatic lithium-ion rechargeable battery with manganese spinel and nickel-cobalt oxide cathode , NEC Research and Development 2000 41 ( 1 ) : 13-17
[52].Pouillerie, C. Perton, F. Biensan, P. Peres, J.P. Broussely, M. Delmas, C., Effect of magnesium substitution on the cycling behavior of lithium nickel cobalt oxide , Journal of Power Sources 2001 96 (2) : 293-302
[53].Liu, Zhaolin Yu, Aishui | Lee, Jim Y., Synthesis and characterization of LiNi_(1-x-y)Co_xMn_yO_2 as the cathode materials of secondary lithium batteries , Journal of Power Sources 81 Sep 1999 Sponsored by: The Electrochemical Societ,; The Electrochemical Society of Japan; International Society of
Electrochemistry; Danionics; Eveready Battery Company Inc. Elsevier Sequoia SA: 416-419
[54].Alcantara, R. Jumas, J.C. , Lavela, P. , Olivier-Fourcade, J. ,Perez-Vicente, C., Tirado, J.L., X-ray diffraction, 57Fe Mossbauer and step potential electrochemical spectroscopy study of LiFe_yCo_(1-y)O_2 compounds , Journal of Power Sources 81 Sep 1999 Sponsored by: The Electrochemical Societ,; The Electrochemical Society of Japan; International Society of Electrochemistry; Danionics; Eveready Battery Company Inc. Elsevier Sequoia SA : 547-553
[55].Hirano A, Kanno R, Kawamoto Y, et al. Solid State Ionics, 1995,78:123-131.
[56].Liu Han-san, Yang Yong, Zhong-ru, et al. New progress in studies of lithium nickel oxides as positive electrode materials[J]. Electrochemistry, 2001,7(2): 145-154.
[57].Tang Zhi-yuan, Li Jian-gang, Xue Jian-jun, et al. On the synthesis and modification of LiNiO_2 [J]. Battery Bi-monthly, 2001,31 (1): 10-13.
[58].Yang Qinghe, Zhang Jong, Jin Zhangkao ,et al. Study on LiNi_(0.8)Co_(0.2)O_2 as cathode materials. The 23rd chemistry and physics power souces conference of China[C]. Xinxiang,1998:347.
[59].Cho J, Park B. Preparation and electrochemical/thermal properties of LiNi_(0.74)Co_(0.26)O_2 cathode materials[J]. J. Power Sources, 2001,92: 35-39.
[60].Ohzuku T,Nakura K, Aoki T, Comparative study of solid-state redox reactions of LiCo(1/4)Ni_(3/4)O_2 and LiAl_(1/4)Ni_(3/4)O_2 for lithium-ion batteries[J]. Electrochim Acta, 1999,45:151-160.
[61].Delmas C, Saadounne I, Rougier A. The cycling properties of the LiNi_(1-y)Co_yO_2 electrode [J]. J Power Sources, 1993,43-44:595-602.
[62].Cho J., Jung H., Park Y., Kim G,, Lim H.S., J. Electrochem. Soc., 2000,147,15.
[63].Ohzuku T., Ueda A., Nagayama M., Iwakoshi Y., Komori H., Electrochimica Acta, 1993,106,451.
[64].Yang wensheng. Synthesis and electrochemical studies of cathode materials for rechargeable lithium ion batteries [D]. Bejing: Unibersity of Science and Technology
[65].Delmas C, Peres J P, Rouier A, et al. On the behavior of the LiNiO2 system: an electrochemical and structural overview [J]. Journal of Power Sources, 1997,68:120~125
[66].Tsutomu Ohzuku, Atsushi Ueda, and Masaru Kouguchi. Synthesis and Characterization of LiAl_(1/4)Ni_(3/4)O_2 for lithium ion (shuttlecock) batteries [J].J.Electrochem. Soc., 1995,142(12):
[67].Neudecker B, J., Zuhr R.A., Kwak B.S., et al. Lithium Manganese Nickel Oxides
Li(Mn_yNi_(1-y))_(2-x)O_2 [J]. J. Electrochem. Soc., 1998,145(12):
[68].朱文学,廖列文,崔英德.均匀沉淀法制备纳米四氧化三钴微粉.无机盐工业2002,01,34(1):3-4.
[69]. Reimers J N, Li W, Dahn J R. Short-range Cation Ordering in Li_xNi_(2-x)O_2 [J]. Phys Rev B, 1993,47:8486~8493
[70]. Rougier A, Gravereau P, Delmas C. Optimization of the Composition of the Li_(1-z)Ni_(1+z)O_2 Electrode Materials: Structural, Magnetic, and Electrochemical Studies[J]. J Electrochem Soc,1996,143:1168~1175
[71]. Li W, Reimers J N, Dahn J R, Crystal Structure of Li_xNi_(2-x)O_2 and a Lattice-gas Model for the Order-disorder Transition [J]. Phys Rev B, 1992,46:3236~3245
[72]. Reimers J N, Dahn J R. Spin Glass Behavior in the Frustrated Antiferromagnetic LiNiO_2[J]. J Solid State Chem, 1993,102:542~552
[73]. Reimers J N, Li W, Dahn J R. Short-range Cation Ordering in Li_xNi_(2-x)O_2 [J]. Phys Rev B, 1993,47:8486~8493
[74]. Fujita Y, Amine K, Maruta J,et al. LiNi_(1-x)Co_xO_2 prepared at low temperature using β- Ni_(1-x)Co_xOOH and either LiNO_3 of LiOH [J]. Journal of Power Sources 1997,68:126~130
[75]. Wang G X. Structure, physical and electrochemical characteriztion of LiNi_(1-x)Co_xO_2 solid solution [J]. J Power Sources, 2000,85:279-283.