钒液流电池双极板厚度对电池性能的影响

Effect of Bipolar Plate Thickness on Vanadium Liquid Flow Battery Performance

以聚乙烯树脂为基体,膨化石墨为导电填料,热压成型法制备不同厚度钒电池双极板,测试双极板物理性能及腐蚀电流。组装测试电池,考察在不同电流密度以及不同浓度电解液中的充放电性能。结果表明:合适的厚度,能有效降低充电电位,减小浓差极化;提高放电起始电位,增加放电容量。厚度为1.0 mm的双极板组装电池具有良好的充放电性能。在1.6 mol·L-1 V+4.2 mol·L-1 H 2SO 4电解液中,80mA·cm-2电流密度下,能量效率为83.32%,电流效率为94.30%,电压效率为89.08%。

Different thickness bipolar plates were prepared with polyethylene resin as matrix and expanded graphite as conductive fillerby hot pressing moldingmethod.The basic physical properties and corrosion current of the bipolar plates were tested.Vanadium liquid flow batteries were assembled to test charging and discharging performance with different current densities and concentrations electrolytes.The results show that suitable thickness can effectively reduce charging potential and concentration polarization;increase the discharge potential and discharge capacity.The 1.0 mm bipolar plate battery has good charge and discharge performance.In 1.6 mol·l-1 V+4.2 mol·L-1 H 2SO 4 electrolyte,the energy efficiency is 83.32%,the current efficiency is 94.30%,and the voltage efficiency is 89.08%at the current density of 80mA·cm-2.