摘要：本文采用高温固相法合成Li7La3Zr2O12石榴石型固体电解质。在制备过程中掺杂不同的稀土元素（RE=Nd，Sm，Gd，Dy，Er）以及不同Nd元素含量（0.02mol≤x≤0.10mol）在SEM，XRD，EIS等仪器的操作下，对固体电解质样片进行表征。从而能够得出Li6.6+xLa3Zr1.6-xSb0.4RExO12固体电解质的离子电导率、相对致密度、收缩率等具体数值，通过对结果的对比研究表明，在烧结温度为1160℃，保温时间为12h的条件下，选择Nd为掺杂元素以及掺Nd含量为x=0.06时，固体电解质样片的离子电导率、相对致密度和收缩率最高，分别为4.43×10-4 S·cm-1，89.02%，9.17%。XRD结果也显示该组样片为纯立方相结构。SEM结果表明该组样片晶粒接触最为紧密，晶界较不明显。

关键词： 离子电导率 ；固体电解质 ；相对致密度 ；收缩率

Preparation of cerium-doped strontium zirconate electrolytes

Abstract:In this paper, Li7La3Zr2O12 garnet solid electrolyte was synthesized by high temperature solid phase method.  Different rare earth elements (RE=Nd, Sm, Gd, Dy, Er) and different Nd contents (0.02mol≤x≤0.10mol) were doped in the preparation process under the operation of SEM, XRD, EIS and other instruments. Solid electrolyte samples were characterized.  The specific values of ionic conductivity, relative density and shrinkage of Li6.6+xLa3Zr1.6xSb0.4RExO12 solid electrolyte can be obtained. The comparison of the results shows that the sintering temperature is 1160°C and the holding time is 12h. Under the conditions, the ionic conductivity, relative density and shrinkage of the solid electrolyte samples were the highest when Nd was selected as the doping element and the Nd content was x = 0.06, which was 4.43×10-4 S·cm-1, 89.02%, respectively, 9.17%.  XRD results also showed that the sample was pure cubic phase structure.  The SEM results show that the crystal grains of the sample are the most compact and the crystal grain boundaries are less obvious.

Keywords :ionic conductivity; solid electrolyte; relative density; Contractibility rate

目录

1 绪论 1

1.1 引言 1

1.2 锂离子电池 1

1.2.1 锂离子电池的组成 1

1.2.2 锂离子电池工作原理 2

1.3 锂离子电池电解质 2

1.3.1 锂离子电池电解质的分类 2

1.4 无机固体电解质 3

1.4.1 硫化物固体电解质 3

1.4.2 氧化物固体电解质 4

1.4.3 钙钛矿型固体电解质 4

1.4.4 LISICON型固体电解质 4

1.5 石榴石型固体电解质 5

1.5.1 石榴石型固体电解质的研究现状 5

1.5.2 石榴石型固体电解质的掺杂 6

1.5.3 Zr位掺杂 6

1.5.4 不同掺杂条件的影响 6

   1.5.5 制备方法.......6

1.6 研究内容 7

2 实验部分 9

2.1 原料、试剂及仪器 9

2.2 工艺流程及步骤 10

2.3 LiLaZrSbREO固体电解质的制备 10

2.3.1 Li6.6+xLa3Zr1.6-xSb0.4NdxO12 ((0.02 ≤ x ≤ 0.10)固体电解质的制备 10

2.3.2 不同元素Li6.66La3Zr1.54Sb0.4RE0.06O12固体电解质的制备 11

2.4 产物表征 11

2.4.1 X射线衍射（XRD） 11

2.4.2 扫描电子显微镜（SEM） 11

2.4.3 交流阻抗（EIS） 12

3 结果与讨论 14

3.1 使用不同元素掺杂对Li6.66La3Zr1.54Sb0.4RE0.06O12(RE=Nd,Sm,Gd,Dy,Er)固体电解质性能的影响 14

3.1.1 不同元素对Li6.66La3Zr1.54Sb0.4RE0.06O12(RE=Nd,Sm,Gd,Dy,Er)固体电解质离子电导率的影响 14

3.1.2 不同元素对Li6.66La3Zr1.54Sb0.4RE0.06O12(RE=Nd，Sm，Gd，Dy，Er)固体电解质相对致密度的影响 2

3.1.3 不同元素对Li6.66La3Zr1.54Sb0.4RE0.06O12(RE=Nd,Sm,Gd,Dy,Er)固体电解质晶形结构的影响 3

3.1.4 不同元素对Li6.66La3Zr1.54Sb0.4RE0.06O12固体电解质显微结构的影响 5

3.2 Nd含量对Li6.6+xLa3Zr1.6-xSb0.4NdxO12固体电解质性能的影响 20

3.2.1 Nd含量对Li6.6+xLa3Zr1.6-xSb0.4NdxO12固体电解质离子电导率的影响 20