Efficient Low Temperature Performance of All Solid-State Zinc-Air Batteries with MnCo2O4/Carbon Fiber Bifunctional Electrocatalyst and Poly(Acrylic Acid) (PAA) Gel Polymer Electrolyte

Spinel type MnCo2O4 coated on asphaltene based carbon fibers (MnCo2O4/CF) was used as the electrode material/electrocatalyst for air electrodes for zinc-air batteries (ZABs). The batteries were assembled using an alkaline poly(acrylic acid) hydrogel electrolyte. The low temperature battery performance of the prepared ZAB cells was studied in terms of charge/discharge voltage and efficiency at different current densities, cycle life, power density, and cell voltage at temperatures between -45 degrees C and 21 degrees C. At all temperatures, the ZABs successfully completed 200 cycles of charge/discharge (100 h) at 2 mA cm(-2) which is double the current density reported in the recent literature. The maximum power densities at 0 and -45 degrees C were 75 and 12 mW cm(-2), respectively. The good performance is attributed to the porous design of the air electrode and the use of an efficient electrocatalyst and an optimized gel polymer electrolyte.