新型固体电解质Li_3PO_4-LiAlO_2的合成及其电化学性能研究  

Preparation and Electrochemical Properties of LiAlO_2-Li_3PO_4 Solid State Lithium Ion Electrolyte Materials

作　　者：祝宝军[1] 陶颖[2] 王伟[1] 李玉平[1] 陈石林[1] 

机构地区：[1]湖南大学材料科学与工程学院,湖南长沙410082 [2]中南大学材料科学与工程学院,湖南长沙410083

出　　处：《湖南大学学报（自然科学版）》2014年第7期35-39,共5页Journal of Hunan University:Natural Sciences

基　　金：国家自然科学基金资助项目(59493300);教育部博士点基金资助项目(9800462)

摘　　要：采用固相合成法制备了Li3 PO4-LiAlO2固态锂离子电解质材料.研究了摩尔配比、煅烧温度对产物相组成、颗粒形貌、电性能的影响.结果表明：当P/Al化学计量比为1∶1时,煅烧后试样中存在片状的γ-LiAlO2和球状的γ-Li3 PO4两相,粒径约为0.5~1μm.当P/Al化学计量比为3∶1时,煅烧后试样主要是Al掺杂的球状γ-Li3 PO4固溶体.此样品1000℃煅烧后,离子电导率为6.4×10^-5 S/cm,说明Al掺杂能有效提高γ-Li3 PO4无机固体电解质离子电导率.1100℃煅烧后,样品锂离子电导率降低.循环伏安曲线研究表明,Al掺杂γ-Li3 PO4无机固体电解质样品在饱和LiNO3水溶液中具有较好的可逆性,其电化学窗口达到1.5 V.A series of LiAlO2-Li3 PO4 solid state lithium ion electrolyte materials were prepared through solid-phase reaction.The influences of experimental operating parameters such as the Molar ratio of mate-rials,and the sintering temperature on the characteristics of the sintered samples were investigated.The results showed that,at 1∶1 stoichiometric ratio of LiAlO2 and Li3 PO4 ,the specimens sintered at 1 000 ℃consisted ofγ-LiAlO2 flakes andγ-Li3 PO4 spheres,and the sizes of particles ranged from 0.5 to 1 μm. When the stoichiometric ratio of LiAlO2 and Li3 PO4 was 1∶3,the specimens sintered at 1 000 ℃ consisted of mainly Al doped sphericalγ-Li3 PO4 solid solution and its ionic conductivity was 6.4×10^-5 S/cm.It in-dicated that Al doping could effectively improve the ionic conductivity of Li3 PO4 inorganic solid electrolyte. When the Al doped specimens were sintered at 1 100 ℃,the ionic conductivity decreased.The results of cyclic voltammetry showed that the Al dopedγ-Li3 PO4 solid electrolyte materials had a good electrochemi-cal reversibility in saturated LiNO3 solution,and an electrochemical window of 1.5V was observed.

关 键 词：锂电池 固体电解质 离子电导率 电化学性能 

分 类 号：TM910.4[电气工程—电力电子与电力传动]