Zinc-air fuel cells (ZAFCs) with flowing particulate Zn anode are gaining momentum with respect to cognate and competing flow-battery technologies, such as zinc-air batteries with immobilized zinc anode zinc-bromine, zinc-cerium and zinc-vanadium flow-batteries, owing to better energy storage flexibility and control of recharge, as well as environmental compatibility. Notwithstanding its appeal, the ZAFC concept still exhibits several operational aspects that warrant dedicated studies, mainly regarding the impact of operating conditions on anode passivation and air cathode degradation. To this aim, systematic experimentation with real devices and simple, but robust electroanalytical approaches, that would enable quantitative handling of large corpora of experimental data, are highly desirable. The literature available to date, is mainly concerned with specific issues regarding device engineering or cathode materials, while systematic and quantitative work on the electrochemical response of the device is missing. This work contributes to bridging this gap, proposing a simple and physically transparent method to follow the variations of cell response to changes in operating conditions, through the measurement of polarization curves and their fitting with a very simple, but original and robust macro-electrokinetic equation, enabling a clear correlation between overvoltage components and cell state. In addition to original measurements with a self-built laboratory-scale device, we fitted and analysed all ZAFC polarization curves reported in the literature. Parametric analysis of the model is complemented by materials-science data, targeting selected observables, relevant to polarization curve analysis.

具有流动颗粒锌阳极的锌空气燃料电池 (ZAFC) 在同源和竞争流动电池技术方面正在获得发展势头，例如具有固定锌阳极锌溴、锌铈和锌钒流动电池的锌空气电池。电池，由于更好的储能灵活性和充电控制，以及环境兼容性。尽管具有吸引力，但 ZAFC 概念仍然展示了几个值得专门研究的操作方面，主要是关于操作条件对阳极钝化和空气阴极退化的影响。为此，使用真实设备和简单但强大的电分析方法进行系统实验，这将能够对大型语料库进行定量处理实验数据，是非常可取的。迄今为止可用的文献主要关注与器件工程或正极材料有关的具体问题，而缺少关于器件电化学响应的系统和定量工作。这项工作有助于弥合这一差距，提出了一种简单且物理透明的方法，通过测量极化曲线及其与非常简单但原始且稳健的宏观电动方程的拟合来跟踪电池对操作条件变化的响应变化，使过电压分量和电池状态之间有明确的相关性。除了使用自制的实验室规模设备进行原始测量外，我们还拟合并分析了文献中报道的所有 ZAFC 极化曲线。