Full commercialization of vanadium flow batteries requires a high current density operation. However, this can be only realized when associated large polarizations of the cell are properly reduced. Of all the cell components, the porous electrode plays a critical role in determining cell polarizations since it directly relates to each of the polarizations. Despite that, an in-depth understanding of electrode compression impact on polarizations of a flow cell is still limited in literature. In this work, a quantitatively experimental study to unveil the electrode compression impact on each of the polarizations as well as the performance of a vanadium flow cell is conducted by employing a symmetric cell configuration. Four different compression ratios are investigated by both ex-situ characterizations and in-situ symmetric cell tests, which successfully reveal its influence on activation, ohmic and concentration polarizations at varied operating current densities. Charge-discharge cycling tests further prove the significance of electrode compression to both efficiency and discharge capacity, while also delivering an optimal compression ratio for the investigated flow cell. Such a quantitative analysis not only promotes a deep understanding of the importance of electrode compression to cell performance, but is also of vital importance for stack design and optimization in practice.
Zhang, Kaiyue,Yan, Chuanwei,Tang, Ao. Unveiling electrode compression impact on vanadium flow battery from polarization perspective via a symmetric cell configuration[J]. JOURNAL OF POWER SOURCES,2020,479.
Zhang, Kaiyue,Yan, Chuanwei,&Tang, Ao.(2020).Unveiling electrode compression impact on vanadium flow battery from polarization perspective via a symmetric cell configuration.JOURNAL OF POWER SOURCES,479.
Zhang, Kaiyue,et al."Unveiling electrode compression impact on vanadium flow battery from polarization perspective via a symmetric cell configuration".JOURNAL OF POWER SOURCES 479(2020).