模板法制备三维多孔LiMnPO_4正极材料及电化学性能  

Preparation by Templating Method and Electrochemical Characteristics of Three-dimensional Multiporous LiMnPO_4 as Cathode Material

作　　者：华丽[1,2] 喻鑫[1] 

机构地区：[1]湖北第二师范学院化学与生命科学学院,武汉430205 [2]华中科技大学材料科学与工程学院,武汉430074

出　　处：《硅酸盐学报》2017年第10期1432-1438,共7页Journal of The Chinese Ceramic Society

基　　金：国家自然科学基金(51171068);湖北省教育厅高等学校优秀中青年科技创新团队建设计划项目(T201225);湖北省教育厅教学研究项目(No.2014395);湖北省重点实验室建设计划项目

摘　　要：以单分散法制备的聚甲基丙烯酸甲酯(PMMA)微球为模板,合成三维多孔(3DOM)LiMnPO_4锂电池正极材料,制备的材料为橄榄石型结构。N_2吸附-脱附分析显示,3DOM LiMnPO_4比表面积较大,为34.63 m^2/g。电化学性能测试表明,首次比容量接近于120 m A·h/g,循环充放电60次时仍保持较好的稳定性。模板法获得的LiMnPO_4呈多孔结构,有利于降低离子或电荷迁移到电解液或电极表面的阻力,从而降低了电极表面的极化,有利于锂离子脱嵌,进而提高充放电的循环稳定性。Three-dimensional multiporous（3DOM） LiMnPO4 as a cathode material for lithium ion battery was synthesized with polymethyl methacrylate（PMMA） microspheres as templates prepared by a monodisperse polymerization method. Based on the results by X-ray diffraction, the 3DOM LiMnPO4 appears a olivine structure. By N2 adsorption-desorption analysis, the 3DOM LiMnPO4 has a greater specific surface area of 34.63 m^2/g. The electrochemical characteristics analysis shows that the material has a stable charge-discharge platform, but it has the 1st cycle capacity of 120 m Ah/g and the better stability after 60 charge-discharge cycles. The multiporous structure of LiMnPO4 favors the reduction of ion or charge transfer resistances in electrolyte or on the electrode surface, thus decreasing the polarization of the electrode surface, being benefit to Li＋ extraction and insertion, and improving the stability of charge-discharge cycles.

关 键 词：三维多孔结构 磷酸锰锂 模板法 锂离子电池 电化学性能 

分 类 号：O646[理学—物理化学]