“…The ultimate goal for advanced sodium ion battery devices has never changed, that they should be thoroughly competitive with the lithium ion battery in energy density, power density, and lower overall manufacturing cost (Tang et al, , 2018Zhang et al, 2017Zhang et al, , 2019Guo et al, 2020). For fullcell sodium ion battery devices, the emphasis always falls on the cathode parts, since they possess key parameters such as high enough operation voltages, large theoretical capacity, and most of all, acceptable high-rate capability.…”