Glycyrrhizic acid secondary doping PEDOT: PSS as conductive additive to facilitate H+ storage for flexible Zn||MnO2 batteries

A topological interconnected conductive network of glycyrrhizic acid (GL) secondary doping poly(3, 4-ethylenedioxythiophene): poly(styrenesulfonate) (PEDOT: PSS) is designed as the conductive additive for Zn||MnO₂ batteries. GL as a “proton reservoir” provides the stable H⁺ reserve for PEDOT: PSS during long-term cycling and permanently changes the chemical structure of PEDOT: PSS through strong ionic bond coordination, improving electronic conductivity of PEDOT: PSS. The constructed conductive network possess a complete conductive channel for MnO₂ active particles and abundant pores for ionic transport, thus can optimize charge transfer paths and increase H⁺ storage. As a result, the capacity of optimized Zn||MnO₂ battery can reach up to 521.16mAh g⁻¹ at 0.1 A g⁻¹ and its retention rate of 90.4 % after 100 cycles. In addition, flexible Zn||MnO₂ battery shows excellent flexibility and electrochemical stability under different bending angles. This study of conductive additive provides further insights into the design of highly conductive and capacity Zn||MnO₂ batteries.