Application of Composite Porous YSZ Ceramic Separators in Aqueous Zinc Ion Batteries

Aqueous zinc ion batteries have received a great deal of attention, due to their excellent safety and high-capacity density. However, zinc dendrites, which are prone to rapid growth in aqueous solutions, constitute an obvious obstacle to the development of aqueous zinc batteries. Conventional glass fiber separators are susceptible to dendrite penetration, owing to the poor structural stability. Porous YSZ ceramic sheets, with main pore size of about 6 μm and porosity up to 45.8887%, were developed by using porous ceramic preparation process. The stable pore structure of the porous YSZ ceramics effectively enhanced the cycle life of the battery. Specifically, the aqueous zinc ion battery based on the porous YSZ separators maintained a stable cycle of 763 h at a current density of 1 mA·cm^-2. Attempts have been tried to improve performances of the ceramic separator by using an interface modification method. It is finally found that weighing paper coated unilateral carbon could be used as the modification layer between the ceramic separator and the electrodes, further improving the cycle stability of the battery, while the composite ceramic separator symmetric batteries reached a cycle time of 1016 h. Stable ceramic pores and extremely low electronic conductivity effectively slow down the growth of Zn dendrites, while the solid and conductive interface modification layer played an important role in homogenizing the distribution of the interfacial electric field.Therefore, such composite ceramic separators showed excellent stability of aqueous ion batteries.