Enhancing understanding of pressure drop in carbon porous electrodes for vanadium redox flow batteries

The pressure drop in redox flow batteries contributes to internal energy loss in the battery system. The seamless carbon material is suitable for analyzing pressure drops due to its uniform structure of interconnected pores. The pressure drop of the full cell was measured with different interconnected pore sizes ranging from 4.7 mu m to 47 mu m. The pressure drop can be analyzed using a semi-theoretical equation based on the Kozeny-Carman equation. The presented semi-theoretical equation can assist in designing the interconnected pore structure of electrode materials for redox flow batteries. Additionally, the pressure drop in relatively thin (0.4 mm) electrodes can be analyzed using the Hagen-Poiseuille equation, indicating that the tortuous effect is negligible. The seamless carbon materials with various interconnected pore diameters exhibit a trade-off relationship between liquid permeability and current density.

Automated summary

This study analyzes the pressure drop issue in redox flow batteries and proposes an analytical model applicable to different materials. The results show that the interconnected pore structure of seamless carbon materials has a significant impact on battery performance, and there is a trade-off relationship between liquid permeability and current density.