在溶液中制备FePO_4·2H_2O前驱体,利用氢气还原法于650℃制得了锂离子电池正极材料LiFePO_4,并对其进行了包覆和掺杂.采用X射线衍射法(XRD)、扫描电镜法(SEM)、循环伏安法(C-V)、交流阻抗法(EIS)及充放电测试对材料进行了结构表征和电化学性能测试.结果表明,该方法制得的材料具有单一的橄榄石结构,样品形貌规则、颗粒均匀.包覆碳和掺镁后,材料具有较低的阻抗及较高的首次放电比容量,LiFePO_4、LiFePO_4/C、LiMg_(0.01)Fe_(0.99)PO_4/C的首次放电比容量分别为125.09mA·h/g、139.17mA·h/g、146.97mA·h/g.
LiFePO_4 materials are prepared by hydrogenous reduction(a method of preparing LiFePO_4 material with prue H_2 gas as protective and reducing gas)with FePO_4·2H_2O. The.samples are characterized by X-ray diffraction(XRD),scanning electron microscopy(SEM),cycle voltammetry(C-V)and electrochemical performance testing.The results show that materials with a single olivine structure,rules of the sample morphology and particle uniformity.It has a lower post-impedance,and higher initial discharge capacity after coated with carbon and magnesium-doped(LiFePO_4 125.09mA·h/g,LiFePO4/C 139.17mA·h/g and LiMg_(0.01)Fe_(0.99)PO_4/C 146.97mA·h/g).
参考文献
| [1] | Tarascon J M .Armand M Issues and challenges facing rechargeable lithium batteries[J].Nature,2001,414(15):359. |
| [2] | 戴曦,唐红辉,杨平,张传福.LiFePO4正极材料的研究进展[J].材料导报,2005(08):69-71. |
| [3] | Andersson A S;Thomas J O .The source of first-cycle capacity loss in LiFePO_4[J].Journal of Power Sources,2001,97-98:498. |
| [4] | Prosini P P;Carewska M et al.Long-term cyelability of nanostructured LiFePO_4[J].Electrochimica Acta,2003,48:4205. |
| [5] | 杨威,曹传堂,曹传宝.共沉淀法制备锂离子电池正极材料LiFePO4及其性能研究[J].材料工程,2005(06):36-40. |
| [6] | Park K S;Lee S B et al.Synthesis of LiFePO_4 with fine particle by co-precipitation method[J].Materials Research Bulletin,2004,39:1803. |
| [7] | 张自禄,卢嘉春,李雪松,杨裕生.LiFePO4的蔗糖改性研究[J].电池,2007(01):3-5. |
- 下载量()
- 访问量()
- 您的评分：
-
10%
-
20%
-
30%
-
40%
-
50%