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Volume 28 Issue 10
Oct.  2021

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Tao Wei, Zao-hong Zhang, Qi Zhang, Jia-hao Lu, Qi-ming Xiong, Feng-yue Wang, Xin-ping Zhou, Wen-jia Zhao,  and Xiang-yun Qiu, Anion-immobilized solid composite electrolytes based on metal-organic frameworks and superacid ZrO2 fillers for high-performance all solid-state lithium metal batteries, Int. J. Miner. Metall. Mater., 28(2021), No. 10, pp. 1636-1646. https://doi.org/10.1007/s12613-021-2289-z
Cite this article as:
Tao Wei, Zao-hong Zhang, Qi Zhang, Jia-hao Lu, Qi-ming Xiong, Feng-yue Wang, Xin-ping Zhou, Wen-jia Zhao,  and Xiang-yun Qiu, Anion-immobilized solid composite electrolytes based on metal-organic frameworks and superacid ZrO2 fillers for high-performance all solid-state lithium metal batteries, Int. J. Miner. Metall. Mater., 28(2021), No. 10, pp. 1636-1646. https://doi.org/10.1007/s12613-021-2289-z
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研究论文

一种利用具备阴离子固定作用的MOF以及酸性ZrO2改性的全固态锂离子电池复合电解质

  • Research Article

    Anion-immobilized solid composite electrolytes based on metal-organic frameworks and superacid ZrO2 fillers for high-performance all solid-state lithium metal batteries

    + Author Affiliations
    • Anion-immobilized solid composite electrolytes (SCEs) are important to restrain the propagation of lithium dendrites for all solid-state lithium metal batteries (ASSLMBs). Herein, a novel SCEs based on metal-organic frameworks (MOFs, UiO-66-NH2) and superacid ZrO2 (S-ZrO2) fillers are proposed, and the samples were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), energy dispersive X-ray spectroscopy (EDS), thermo-gravimetric analyzer (TGA) and some other electrochemical measurements. The –NH2 groups of UiO-66-NH2 combines with F atoms of poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) chains by hydrogen bonds, leading to a high electrochemical stability window of 5 V. Owing to the incorporation of UiO-66-NH2 and S-ZrO2 in PVDF-HFP polymer, the open metal sites of MOFs and acid surfaces of S-ZrO2 can immobilize anions by strong Lewis acid-base interaction, which enhances the effect of immobilization anions, achieving a high Li-ion transference number (t+) of 0.72, and acquiring a high ionic conductivity of 1.05×10–4 S·cm–1 at 60°C. The symmetrical Li/Li cells with the anion-immobilized SCEs may steadily operate for over 600 h at 0.05 mA·cm–2 without the short-circuit occurring. Besides, the solid composite Li/LiFePO4 (LFP) cell with the anion-immobilized SCEs shows a superior discharge specific capacity of 158 mAh·g–1 at 0.2 C. The results illustrate that the anion-immobilized SCEs are one of the most promising choices to optimize the performances of ASSLMBs.

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