Construction of high-capacity all-solid-state battery using hydride negative electrode

水素化物負極を用いた高容量全固体電池の構築

So far, it has been clarified that when we use the high-capacity negative electrode materials such as Mg(BH 4 ) 2 , Ca(BH 4 ) 2 , and MgH 2 , solid electrolytes can be generated by electrode reaction. As the electrode reaction products of MgH 2 , LiH and Mg will form by Li insertion, and despite the low Li ion conductivity of LiH, it can be used as an excellent negative electrode of all-solid-state battery due to the self-generation of solid electrolyte. In this study, it is necessary to clarify the ionic conductivity of the formed Li salt and the three-dimensional distribution of reactants, products, and carbon in the electrode mixture during charging and discharging for the further understanding of the factor than affect the battery characteristic of the negative electrode that using the self-generated solid electrolyte.

これまで、Mg(BH4)2、Ca(BH4)2、MgH2といった高容量負極材料にLiイオンを挿入すると固体電解質が自己生成することを明らかにしている。MgH2はLi挿入によりLiHとMgを生成するが、LiHのLiイオン伝導度は低いにも関わらず、固体電解質の自己生成により優れた全固体電池負極として利用できる。本研究では、生成するLi塩のイオン伝導性や、充放電中の電極合材中の反応物・生成物・炭素の3次元分布を明らかにすることで、自己生成固体電解質を用いた負極の電池特性を決定する要因を解明する。