Abstract
Spark plasma sintering (SPS) is a convenient technique to assemble electrode composites of positive and negative electrode active materials and inorganic solid electrolyte with similar sintering temperatures. Here, a new process is proposed to combine the separate sintering steps of positive and negative electrode composite pellets, and their subsequent assembling step with metaboric add (HBO2). All-Solid-State Na Batteries using Na4Co3(PO4)(2)P2O7 (NCPP) and Na3V2(PO4)(3) (NVP) were assembled as positive and negative electrodes, respectively. The NCPP and the NVP electrode composite powders were sintered at individual appropriate temperatures and pressures with solid electrolyte, Na3Zr2(SiO4)(2)PO4(NZSP) layers. The NZSP layers of the prepared pellets were successfully joined with heated HBO2 sandwiched between both pellets (NVP electrode composite/NZSP and NZSP/NCPP electrode composite). The fabricated all-oxide-powder type battery has demonstrated a discharge capacity of 73 mAh g(-1) at 200 degrees C.