OPTIMIZATION OF ELECTROLYTE AND CATHODE LAYER FOR ZN/MNO2 ALKALINE BATTERIES

Abstract

Rechargeable zinc-manganese dioxide (Zn-MnO2) alkaline chemistry has intrigued the research community due to its low cost, inherent safety, and high theoretical capacity for its application in medium voltage devices like wearable electronics. However, this chemistry is still pre-mature for commercialization due to the formation of irreversible compounds and requires more effort to enhance its performance by optimizing anode, cathode and electrolyte. Therefore, several experiments were performed on electrolytes and cathode substrates to gain insight into their behavior. Two electrolyte samples with different thicknesses (170 ?m and 270 ?m) were tested for swelling ratio, ionic conductivity, and ion transference number. Moreover, the surface properties of stainless steel mesh and graphene sheet were studied to determine their compatibility with the active material. The analysis of these results led to the conclusion that electrolytes with a thickness of 170 ?m and graphene sheets are optimal choices for electrolyte and cathode substrates for Zn-MnO2 batteries. Moreover, with the intercalation of bismuth (Bi) and copper (Cu) in MnO2, the reversibility of the battery was verified through electrochemical tests.