Ion transport in battery materials: Computational methodology and applications

Ion transport properties such as ionic conductivity/resistance are still critical targets for R&D of next-generation batteries such as Na-Ion Battery (NIB) and All-Solid-State-Battery (ASSB). However, due to the complexity of battery materials, many atomistic mechanisms have been still open questions. With DFT-based calculations on HPC facilities like Fugaku, we have studied such phenomena at the atomic scale.
 Regarding NIBs, we recently examined Na-ion migration in Prussian Blue Analogue cathodes and found importance of framework dynamics rather than static cage size, and need of very accurate DFT-MD for such spin systems. DFT-MD investigations of hard carbon anode give novel insights of Na-ion clusterization and diffusion manners as well. Ion transport properties across the solid electrolyte(SE)-coating-electrode interfaces in ASSBs have been investigated as well via the interface CALYPSO technique for sampling stable solid-solid interfaces. A series of studies gave atomistic aspects of Li-ion electrochemical potential throughout the batteries and crucial roles of the interface coating. Finding superionic conductor is still an important issue and we performed several DFT-based studies on ion transport in the SEs. Along this, we have developed a new type of Non-Equilibrium MD method to evaluate chemical diffusivity rather than self-diffusivity.
Overall, these HPC works provide several general pictures that are difficult to be obtained by experiments solely.

References:  https://www.cd-mach.cls.iir.titech.ac.jp/en/tateyama/output/

Short bio: https://www.cd-mach.cls.iir.titech.ac.jp/en/tateyama/cv/

The seminar is realized in the framework of the funded projects:
-MaX- Materials design at the eXascale GA. 101093374
-Hanami GA. 101136269