Synthesis of Na2Ti3O7-based anode for sodium-ion battery using solid state reaction method

Abstract

Na2Ti3O7-based anode for sodium-ion battery was synthesized through solid-state reaction of high purity Na2CO3 and TiO2. The dry and wet mixing by using ethanol assistance were used to compare the effects on their properties. Simultaneous Thermal Analysis (STA) was carried out to determine the temperature of sintering process. Precusors, both from dry and wet mixing, were sintered at 900 °C for 4 h in air. The structure and phase of the sintered samples were characterized by X-ray diffraction (XRD), while the particle size was determined using a particle size analyzer (PSA). The samples were then assembled into coin cells for performance test purposes. The electrochemical processes of all of samples were examined using an automatic battery cycler system. It is shown that ethanol assisted-wet process did not decrease the sintering temperature but it decreased the particle size of samples. Phase analysis showed that the phases for both treatments are Na2Ti3O7 and Na2Ti6O13, and they had a high crystalinity. Cyclic voltammetry shows that all samples have an unbalanced pair of redox peaks and show formation SEI layers.