Effect of electrolyte parameters on the discharge characteristics of planar zinc-air flow battery with polymer gel electrolyte as separator

Metal-air batteries are emerging as a preferable choice among different battery technologies explored as an alternative to existing lithium-ion batteries. These batteries can outperform the current lithium batteries in terms of specific energy, energy cost, and ability for alternative metal choice. Metal-air flow batteries are being investigated in place of conventional metal-air batteries to reduce metal passivation and dendrite formation which are considered to be the major limitations in conventional metal-air batteries. For emerging battery chemistry, a parametric study is necessary to identify the batteries performance variations to identify the optimal technology design. As far as flow batteries are concerned, electrolyte parameters play a notable role in the performance. In this study, we investigate the influence of electrolyte parameters namely, electrolyte flow rate, electrolyte volume (volume stored in the container), and electrolyte concentration to understand the effect of each parameter on the nominal voltage of a planar zinc-air flow battery utilising a polymer gel electrolyte separator. We followed a 2(n) factorial design approach to determine the percentage contribution of each parameter. From this experimental study, we found the percentage contribution of electrolyte concentration to be most significant and the percentage contribution of electrolyte flow rate as reasonably significant. The percentage contribution of electrolyte volume appeared least significant among the chosen parameters. This study will help researchers to perceive the influence of electrolyte parameters on the performance of zinc-air flow batteries.