Abstract:
In order to realize the industrial production of zinc-air battery, the performance of its air diffusion electrode is optimized to make it conducive to the diffusion of gas and to form more three-phase interfaces. The conductive hydrogel is composed of a conductive material and a cross-linked polymer network, the polymer network provides the scaffold, and the conductive material gives the hydrogel good electrical conductivity. The porous structure can give more diffusion paths to the gas, and is also conducive to the load of the catalytic layer, forming more three-phase interfaces. In this paper, polyacrylamide hydrogel was used to synthesize porous polyacrylamide/carbon nanotubes-polyethylene glycol (PAM/CNTs-PEG) conductive hydrogel with polyethylene glycol 2000 (PEG2000) as pore-making agent. The prepared PAM/CNTs-PEG conductive hydrogels were immersed in ethanol solution to form different numbers of mesopores. The effect of different immersion time on the properties of porous PAM/CNTs-PEG conductive hydrogels in flexible zinc-air cells was studied. The experimental results show that the electrochemistry performance of the conductive gel soaked in ethanol for 5 h is the best. When the voltage changes from 1.23 V at 1 mA/cm
2 to 1.11 V at 5 mA/cm
2, the attenuation is only 0.12 V. The maximum power density is 77.35 mW/cm
2 at 8.5 mA/cm
2, and the high gram capacity of 1104.85 mA·h/g at discharge is much higher than that of other conductive gels. It has good electrical conductivity and strain sensitivity and can be used in sensing and other fields.