郑州大学王景涛团队报道了在薄层无机固体电解质层间通道中制备二维有序Li033La0557TiO3晶体实现超快Li⁺转移。研究成果于2021年11月21日发表于国际一流学术期刊《德国应用化学》。

无机超离子导体在高性能全固态锂电池中具有巨大的应用前景。然而，传统无机固体电解质（ISE）由于晶界电阻大、厚度大，其离子导电性一直不能令人满意。

该文中，研究人员通过自组装刚性亲水蛭石（Vr）纳米片制备了一个13μm厚的，层间通道约1.3nm的层状框架。然后，将Li0.33La0.557TiO3（LLTO）前驱体浸渍在层间通道中，然后原位烧结成大尺寸、定向且无缺陷的LLTO晶体。

研究人员发现限制效应使LLTO晶体沿c轴有序排列（最快的Li⁺转移方向），能够生成的15μm厚的Vr LLTO电解质在30℃时具有8.22×105 S cm ^-1的离子电导率和87.2 mS的电导率。这些值比传统LLTO基电解质高出几倍。此外，Vr LLTO电解液的压缩模量为1.24 GPa。全固态Li/LiFePO 4电池具有优异的循环性能。

附：英文原文

Title: Preparing two-dimensional ordered Li0.33La0.557TiO3 crystal in interlayer channel of thin laminar inorganic solid-state electrolyte towards ultrafast Li+ transfer

Author: Ruixin Lv, Weijie Kou, Shiyuan Guo, Wenjia Wu, Yatao Zhang, Yong Wang, Jingtao Wang

Issue&Volume: 2021-11-21

Abstract: Inorganic superionic conductor holds great promise for high-performance all-solid-state lithium batteries. However, the ionic conductivity of traditional inorganic solid electrolytes (ISEs) is always unsatisfactory owing to the grain boundary resistance and large thickness. Here, a 13 μm-thick laminar framework with ~ 1.3 nm interlayer channels is fabricated by self-assembling rigid, hydrophilic vermiculite (Vr) nanosheets. Then, Li  0.33  La  0.557  TiO  3  (LLTO) precursors are impregnated in interlayer channels and afterwards in-situ sintered to large-size, oriented, and defect-free LLTO crystal. We demonstrate that the confinement effect permits ordered arrangement of LLTO crystal along the c-axis (the fastest Li  +  transfer direction), permitting the resultant 15 μm-thick Vr-LLTO electrolyte an ionic conductivity of 8.22×10  5  S cm  1  and conductance of 87.2 mS at 30  o  C. These values are several times’ higher than that of traditional LLTO-based electrolytes. Moreover, Vr-LLTO electrolyte has a compressive modulus of 1.24 GPa. Excellent cycling performance is demonstrated with all-solid-state Li/LiFePO  4  battery.

DOI: 10.1002/anie.202114220

Source: https://onlinelibrary.wiley.com/doi/10.1002/anie.202114220