Thermophysical Characterization of a Layered P2 Type Structure Na₀.₅₃MnO₂Cathode Material for Sodium Ion Batteries

Over the last decade, the demand for safer batteries with excellent performance and lowercosts has been intensively increasing. The abundantly available precursors and environmentalfriendliness are generating more and more interest in sodium ion batteries (SIBs), especially becauseof the lower material costs compared to Li-ion batteries. Therefore, significant efforts are beingdedicated to investigating new cathode materials for SIBs. Since the thermal characterization ofcathode materials is one of the key factors for designing safe batteries, the thermophysical propertiesof a commercial layered P2 type structure Na0.53MnO2cathode material in powder form weremeasured in the temperature range between−20 and 1200◦C by differential scanning calorimetry(DSC), laser flash analysis (LFA), and thermogravimetry (TG). The thermogravimetry (TG) wascombined with mass spectrometry (MS) to study the thermal decomposition of the cathode materialwith respect to the evolved gas analysis (EGA) and was performed from room temperature up to1200◦C. The specific heat (Cp) and the thermal diffusivity (α) were measured up to 400◦C becausebeyond this temperature, the cathode material starts to decompose. ... mehrThe thermal conductivity (λ)as a function of temperature was calculated from the thermal diffusivity, the specific heat capacity,and the density. Such thermophysical data are highly relevant and important for thermal simulationstudies, thermal management, and the mitigation of thermal runaway.