The change of Na storage mechanism from Soft Carbon to Hard Carbon

Dataset for microstructure effect to Na storage mechanism. Abstract: Carbon materials: Soft Carbon and Hard Carbon, are two of the most promising for Sodium ion batteries anodes. However, the relation between Na storage mechanism and microstructure of Carbon materials are well not understood. In this work, we extend our previous phenomenological model and develop an efficient mean field theory for the calculation of OCV of carbon materials ranging from Soft Carbon to Hard Carbon with closed pores and open pores, respectively. Our model utilizes a very simple model for the energetic sites within the microstructure of disordered carbon materials and aims for a unifying picture of the Na storage mechanism in carbon materials ranging from soft carbon to hard carbons. In addition, we also study the impact of the current density on the utilization of energetic sites in the microstructure of hard carbon.