以三乙二醇水溶液为反应介质,在常压和108℃条件下,快速生成含有元素 Li、Fe、P 的前驱体。XRD和SEM分析表明,所得前驱体属于无定形结构,与一定量葡萄糖混合后在600℃下焙烧3h后得到的是纳米级的LiFePO4/C材料。电化学测试结果表明,这种纳米级LiFePO4/C材料在2.3~4.2V之间0.2C倍率下放电容量达到156.3 mAh/g,并且具有较好的放电平台。5和10C放电容量仍能达到133.9和109.9mAh/g,表现出优异的倍率放电特性和循环性能。
The precursor contained element of Li,Fe,P was synthesized in the triethylene glycol (TEG)/H2 O system under ambient pressure and 108℃ during a short time.The XRD and SEM results show that:the ob-tained precursor belonged to amorphous structure,and LiFePO4/C nanocomposites was obtained by sintering at 600℃ with a certain amount of glucose under inert atmosphere for 3h.Electrochemical tests showed that the special capacity of nanometer LiFePO4/C at discharge rates of 0.2 was 156.3mAh/g and has the better dis-charge platform.A capacity of 133.9mAh/g at 5C and 109.9mAh/g at 10C was even achievable,with no signif-icant capacity fading after 200 cycles.Show excellent rate discharge characteristics and cycle performance.
参考文献
| [1] | Padhi AK.;Goodenough JB.;Nanjundaswamy KS. .PHOSPHO-OLIVINES AS POSITIVE-ELECTRODE MATERIALS FOR RECHARGEABLE LITHIUM BATTERIES[J].Journal of the Electrochemical Society,1997(4):1188-1194. |
| [2] | 常照荣,吕豪杰,汤宏伟,付小宁.高密度LiFePO4/C正极材料的合成其及电化学性能研究[J].功能材料,2009(04):618-620. |
| [3] | Sylvain F;Frederic L C;Carole B et al.Comparison be-tween different LiFePO4 synthesis routes and their influ-ence on its physical chemical properties[J].Journal of Power Sources,2003,119-121:252-257. |
| [4] | G. X. Wang;L. Yang;Y. Chen;J. Z. Wang;Steve Bewlay;H. K. Liu .An investigation of polypyrrole-LiFePO{sub}4 composite cathode materials for lithium-ion batteries[J].Electrochimica Acta,2005(24):4649-4654. |
| [5] | Molenda J;Ojczyk W;Swierczek K;Zajac W;Krok F;Dygas J;Liu RS .Diffusional mechanism of deintercalation in LiFe1-yMnyPO4 cathode material[J].Solid state ionics,2006(26/32):2617-2624. |
| [6] | Ho Chul Shin;Sung Bin Park;Ho Jang;Kyung Yoon Chung;Won Il Cho;Chang Sam Kim;Byung Won Cho .Rate performance and structural change of Cr-doped LiFePO{sub}4/C during cycling[J].Electrochimica Acta,2008(27):7946-7951. |
| [7] | Yang S F;Zavalij P Y;Whitting M S .Hydrothermal synthesis of lithium iron phosphates[J].Electrochemistry Communications,2001,3(09):505-508. |
| [8] | Wang Y G;Wang Y R;Hosono E et al.The design of a LiFePO4/carbon nanocomposite with a core-shell struc-ture and its synthesis by an in situ polymerization re-striction method[J].Angewandte Chemie International Edition,2008,47:7461-7465. |
| [9] | Chang, Z.-R.;Liu, Y.;Tang, H.-W.;Yuan, X.-Z.;Wang, H. .DMSO-assisted liquid-phase synthesis of LiFePO_4/C nanocomposites with high-rate cycling as cathode materials for lithium ion batteries[J].Electrochemical and solid-state letters,2011(6):A90-A92. |
| [10] | Lee SB;Cho SH;Cho SJ;Park GJ;Park SH;Lee YS .Synthesis of LiFePO4 material with improved cycling performance under harsh conditions[J].Electrochemistry communications,2008(9):1219-1221. |
| [11] | C. Delacourt;P. Poizot;S. Levasseur .Size Effects on Carbon-Free LIFePO_4 Powders The Key to Superior Energy Density[J].Electrochemical and solid-state letters,2006(7):A352-A355. |
| [12] | Byoungwoo Kang;Gerbrand Ceder .Battery Materials For Ultrafast Charging And Discharging[J].Nature,2009(7235):190-193. |
| [13] | Charles R. Sides;Fausto Croce;Vaneica Y. Young .A High-Rate, Nanocomposite LiFePO_4/Carbon Cathode[J].Electrochemical and solid-state letters,2005(9):A484-A487. |
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