著者

Daisuke Mori Miho Sato Sou Taminato Nobuyuki Imanishi Kota Suzuki Masaaki Hirayama

出版者

The Ceramic Society of Japan

雑誌

Journal of the Ceramic Society of Japan (ISSN:18820743)

巻号頁・発行日

vol.131, no.10, pp.690-695, 2023-10-01 (Released:2023-10-01)

参考文献数

36

被引用文献数

1

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Li ionic conductors that are stable to lithium metal with high ionic conductivity are required as solid electrolytes for all-solid-state lithium metal batteries with high energy density. Lithium dendrite growth leading to short-circuit is one of the major issues to solve for developing practical batteries using lithium metal electrodes. We have introduced Li3PO4 (LPO) and Li3BO3 (LBO) as a grain boundary phase in the garnet-type lithium ionic conductor, Li6.25Ga0.25La3Zr2O12 (LGLZ), by co-sintering. The lattice parameters, sinterability, elemental distribution, particle morphology, and electrochemical properties have been investigated. The sinterability has decreased with the introduction of LPO and LBO, while no significant change in the ionic conductivity is observed. The LGLZ with LPO was unstable to Li metal and did not exhibit the improvement of Li plating/stripping. Meanwhile, the LBO introduction into the grain boundary as a functional core increased the critical current density of the short circuit. Li dendrite growth could be suppressed by modifying the grain boundaries of the sintered body.

著者

Maiko KAWAKUBO Masaki MATSUI Sumihisa ISHIKAWA Atsushi HIRANO Osamu YAMAMOTO Yasuo TAKEDA Nobuyuki IMANISHI

出版者

公益社団法人 電気化学会

雑誌

Electrochemistry (ISSN:13443542)

巻号頁・発行日

vol.82, no.8, pp.642-646, 2014-08-05 (Released:2014-08-05)

参考文献数

14

被引用文献数

2

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Degradation processes of carbon negative electrodes for all-solid lithium polymer batteries were investigated using X-ray diffraction (XRD), electrochemical impedance spectroscopy (EIS) and Scanning Electron Microscope (SEM). The cycling performances of the electrodes are significantly affected by the mixing speed of the electrode slurry. The cross-sectional SEM images of the electrodes containing vapor-grown carbon fiber (VGCF) show that more voids remained in the electrodes, if the slurry was mixed at high speed. The voids in the composite electrode expand and increase during the cycling test of the cell resulting in the capacity fading. On the other hand, the electrodes containing carbon nanotubes (CNT) show an opposite trend, because the high mixing speed improves the dispersibility of the CNT resulting in the formation of the less voids in the electrode. The electrode containing both VGCF and CNT prepared at high mixing speed shows the best cycleability among all the electrodes. In spite of some voids initially form in the electrode, the CNT seems to have prevented further increase and expansion of the voids.