著者

Mika FUKUNISHI Tatsuo HORIBA Mouad DAHBI Kei KUBOTA Satoshi YASUNO Shinichi KOMABA

出版者

The Electrochemical Society of Japan

雑誌

Electrochemistry (ISSN:13443542)

巻号頁・発行日

vol.87, no.1, pp.70-77, 2019-01-05 (Released:2019-01-05)

参考文献数

24

被引用文献数

4

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A nanometer-sized Sn (nano-Sn) powder composite electrode with polyacrylate binder delivers a discharge capacity of 600 mAh g−1 with a good capacity retention for 100 cycles in non-aqueous Na cells, however, a micrometer-sized Sn (micro-Sn) composite electrode exhibits an insufficient cycle performance under the same condition. Although surface analysis of cycled electrodes reveals no apparent difference in solid electrolyte interphase layer formed on the nano- and micro-Sn electrodes, we found that in the case of nano-Sn electrodes the moderately porous composite layers and thin binder coating on Sn particles are responsible for a favorable cycle performance. On the other hand, the dense and less-porous micro-Sn electrode having a relatively thicker coating of binder on micro-Sn particles deteriorates the reversibility of sodium alloying reaction. Therefore, we optimize the electrode preparation process to introduce the suitable porosity and properly thin binder coating in the micro-Sn composite electrodes. The optimization enables the micro-Sn electrode to demonstrate high reversible sodiation capacity of 676–470 mAh g−1 with much improved capacity retention over 100 cycles.