摘要：本文采用高温固相法制备Li6.6+xLa3-xSrxZr1.6Sb0.4O12和Li7.02-yLa2.98Sr0.02Zr2-ySbyO12两种固体电解质。分别研究Sr含量（0.02≤x≤0.1）对Li6.6+xLa3-xSrxZr1.6Sb0.4O12固体电解质和Sb含量（0.1≤y≤0.5）对Li7.02-yLa2.98Sr0.02Zr2-ySbyO12固体电解质的离子电导率，晶体结构，收缩率，相对致密度的影响。结果表明：当Sr含量x=0.02时，Li6.6+xLa3-xSrxZr1.6Sb0.4O12固体电解质的离子电导率最大为5.54×10-4 S·cm-1，相对致密度最大是92.47%，收缩率最大为8.09%；当Sb的掺杂量y=0.40时，Li7.02-yLa2.98Sr0.02Zr2-ySbyO12固体电解质的离子电导率最大为5.54×10-4 S·cm-1，相对致密度最大是92.47%，收缩率最大为8.09%。两组实验所得出的最佳固体电解质为同一种固体电解质，即Sr含量为x=0.02，Sb含量为y=0.40的Li6.62La2.98Sr0.02Zr1.6Sb0.4O12固体电解质。XRD图显示此固体电解质为立方相固体电解质。SEM图像显示此固体电解质的晶粒最大，晶粒排列最为紧密，晶界最为模糊。

关键词： 离子电导率；收缩率；相对致密度；固体电解质；掺杂

Characterization of cerium and strontium doped zirconium oxide electrolytes

Abstract：In this paper, two solid electrolytes, Li6.6+xLa3-xSrxZr1.6Sb0.4O12 and Li7.02-yLa2.98Sr0.02Zr2-ySbyO12, were prepared by high temperature solid-state reaction. The Sr content (0.02 ≤ x ≤ 0.1) for Li6.6+xLa3-xSrxZr1.6Sb0.4O12solid electrolyte and the Sb content (0.1 ≤ y ≤ 0.5) for Li7.02-yLa2.98Sr0.02Zr2-ySbyO12 solid electrolyte were investigated, respectively. Ionic Conductivity, Crystal Structure, Shrinkage, Relative Density Effect. The results show that when the content of Sr is x=0.02, the ionic conductivity of Li6.6+xLa3-xSrxZr1.6Sb0.4O12 solid electrolyte is 5.54×10-4 S·cm-1, and the maximum relative density is 92.47%. The maximum rate is 8.09%. When the doping content of Sb is y=0.40, the maximum ionic conductivity of Li7.02-yLa2.98Sr0.02Zr2-ySbyO12solid electrolyte is 5.54×10-4 S·cm-1. The maximum is 92.47% and the maximum shrinkage rate is 8.09%. The best solid electrolyte obtained from the two sets of experiments was the same solid electrolyte, namely Li6.62La2.98Sr0.02Zr1.6Sb0.4O12 solid electrolyte with Sr content of x=0.02 and Sb content of y=0.40. The XRD pattern shows that the solid electrolyte is a cubic phase solid electrolyte. SEM images showed that the solid electrolyte had the largest grain size, the closest grain arrangement, and the most grain boundary.

Keywords：Ionic Conductivity; Shrinkage; Relative Density; Solid Electrolyte; Doping

目录

1 绪论 1

1.1 引言 1

1.2 锂离子电池 1

1.3 锂离子电池电解质的分类 2

1.3.1 LISICON结构电解质 3

1.3.2 钙钛矿结构固体电解质 3

1.3.3 NASICON型锂离子无机固体电解质 4

1.3.4 石榴石型固体电解质 5

1.3.5 硫化物固体电解质 7

1.4 研究内容 8

2 实验部分 9

2.1 原料、试剂及仪器 9

2.2 工艺流程 9

2.3 工艺步骤 10

2.4 制备固体电解质的原料用量 11

2.4.1 Li6.6+xLa3-xSrxZr1.6Sb0.4O12（0.02≤x≤0.10）固体电解质的制备 11

2.4.2 Li7.02-yLa2.98Sr0.02Zr2-ySbyO12（0.10≤y≤0.50）固体电解质的制备 11

2.5 产物表征 11

2.5.1 X射线衍射（XRD） 11

2.5.2 扫描电子显微镜（SEM） 12

2.5.3 交流阻抗（EIS） 12

3 结果与讨论 15

3.1 Sr含量对Li6.6+xLa3-xSrxZr1.6Sb0.4O12（0.02≤x≤0.10）固体电解质的影响 15

3.1.1 Sr含量对Li6.6+xLa3-xSrxZr1.6Sb0.4O12固体电解质离子电导率影响 15

3.1.2 Sr含量对Li6.6+xLa3-xSrxZr1.6Sb0.4O12固体电解质显微结构的影响 17

3.1.3 Sr含量对Li6.6+xLa3-xSrxZr1.6Sb0.4O12固体电解质晶型结构的影响 18

3.1.4 Sr含量对Li6.6+xLa3-xSrxZr1.6Sb0.4O12固体电解质的相对致密度影响 20

3.1.5 Sr含量对Li6.6+xLa3-xSrxZr1.6Sb0.4O12固体电解质的收缩率 20