Seminarium "Modeling of Complex Systems"

Na-ion batteries are a cheaper alternative to the usual Li-ion batteries that are found in every portable consumer device. Sodium is abundant (it is in table salt) and geographically distributed, making Na-ion technology attractive for small devices and large-scale stationary storage alike – for example, storing solar power plant output and releasing it at night. However, Na-ion battery capacity and performance are not yet fully optimized, compared to decades of research in Li-ion batteries. The operational mechanisms in the most widely employed anode material for Na-ion batteries – hard carbon (HC) – are stilldebated. Despite high theoretical capacity, low operation voltage, and abundance, HC often suffers capacity loss during the first charge-discharge and is extremely sensitive to minor changes in synthesis conditions. The reason is structural complexity:semi-amorphous HC contains defects, semi-crystalline expanded graphite regions, and internal pores – each contributing to Na storage in different ways. In this talk, we will explore the Na storage using density functional theory, cluster expansion [1],and Monte Carlo [2] modeling and disentangle contributions from different structural motifs. Defects are responsible for most of the sloping voltage region and limit power output. Intercalation between graphitic layers is possible only under specificstructural conditions (large spacing between carbon layers), and its voltage signature is strongly affected by the presence of defects. Pores provide most of the useful capacity (the voltage plateau), but their filling is sensitive to pore size distribution anddefects within pores.[1] I. Radchenko, O.I. Malyi, Rational design principles for Na- and Li-ion carbon anodes from interlayer spacing control, PRXEnergy (2026). https://doi.org/10.1103/g52s-znhz[2] I. Radchenko, A.F. Usuga, O.I. Malyi, Kinetic limit in the close pore filling in the hard carbon electrode. unpublished

The seminar will be held in hybrid mode: in room 1.40 (FUW, Pasteura 5).During the seminar the coffee and cakes are provided. Join Zoom Meeting
https://uw-edu-pl.zoom.us/j/96378632993?pwd=MVgdPR80oKaE4pjLufb2NCtg6ql4Ax.1
Meeting ID: 963 7863 2993
Passcode: 569551