聚丙烯酸对钒电池正极热稳定性和电化学性能影响的研究。

Effect of polyacrylic acid on the thermal stability and electrochemical performance of the positive electrolyte for all-vanadium redox flow battery

摘要:

通过原位热稳定性、紫外-可见光谱、拉曼光谱、X射线光电子能谱(XPS)、循环伏安法和充放电方法,研究了聚丙烯酸(PAA)对全钒氧化还原流电池(VRFB)正极电解液的热稳定性和电化学性能的影响。结果表明,PAA添加剂可以提高V(V)电解液的热稳定性。在室温条件下,少量的PAA添加剂能轻微的提高正极电解液的电化学性和VRFB的能量效率。此外,以PAA添加量为3%的正极电解液组装电池,该电池在50 ℃ 时表现出良好的充放电循环性能,其充电容量保持率高于没有添加PAA的电池。

Abstract:

Effect of poly acrylic acid (PAA) addition on the thermal stability and electrochemical performance of the V(V) positive electrolyte for all-vanadium redox flow battery (VRFB) were investigated in this paper by ex-situ stability tests, UV–Vis spectrometry, Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), Cyclic voltammetry (CV) and charge-discharge test. The results indicate that PAA additives can improve the thermal stability of V(V) electrolyte. A small amount of PAA additives can slightly improve electrochemical performance of the positive electrolyte and the energy efficiency of the VRFB at room temperature. Besides, the cell employing the positive electrolyte solution with 3% PAA shows good cycling performance at 50 ℃, the charge capacity retention of which is higher than that of the cell without PAA during the cycling.