Particle Size Effects of the Ni-Rich Cathode Material in All-Solid-State Li-Ion Batteries

Abstract

All-solid-state Li-ion batteries (ASLBs) may be promising candidate to solve the problem because it uses non-flammable inorganic solid electrolytes as an electrolyte and separator. However, ASLBs has serious drawback such as low ionic conductivity compared to liquid electrolyte and have a large interfacial resistance between positive electrode and solid electrolyte in positive electrode. In these regards, reducing particle size of the cathode material can be positive affect to increase the contact area between cathode material and solid electrolyte in the positive electrode to decrease the interfacial resistance. In addition, high capacity Ni-rich cathode material generally was used for high energy density in ASLBs.In this work, we report on the particle size effects of the Ni-rich cathode material synthesized by co-precipitation method in all-solid-state Li-ion batteries. For comparison of the size effect, the physical, chemical, and electrochemical properties were evaluated by X-ray diffraction, field-emission scanning electron microscopy (FE-SEM), electrochemical impedance spectroscopy (EIS) and galvanostatic tests.