Abstract: The influence of different content of lignin sulfonate on the vanadium battery cathode electrolyte is analyzed by the electrochemical method.AC impedance，UV-visible spectra and single battery charge/discharge experiments have verified the effect of lignin sulfonate added.The results show that the dosage is 0.1%，the charge transfer resistance decreases from 5.446 Ω·cm2 to 1.002 Ω·cm2，the double layer capacitance of 4.16 × 10-4 F·cm-2 is reduced to 1.298 × 10-4 F·cm-2.It can indicate that the different content of lignin sulfonate did not significantly affect the excitation wavelength and absorbance，but greatly improve the charge-discharge performance.The lignin sulfonate has a strong chemical and electrochemical stability help to improve the vanadium ion conduction and electrical energy storage.

Key words: all-vanadium redox flow battery, electrolyte, additive, sodium ligninsulfonate

摘要： 摘要〖HTSS〗：采用电化学方法分析了不同含量木质素磺酸钠对钒电池正极电解液的影响。交流阻抗、紫外可见光谱和单电池充放电实验验证了木质素磺酸钠添加后的效果。分析结果表明：添加量为0.1% 时，电荷传递电阻由5.446 Ω·cm2 减小到1.002 Ω·cm2 ，双电层电容由4.16×10-4 F·cm-2 减小到1.298×10-4 F·cm-2 ，添加不同含量的木质素磺酸钠并没有显著影响激发态波长和吸光度，但是充放电性能显著提高，这表明木质素磺酸钠具有很强的化学及电化学稳定性，有利于提高钒离子的传导和电能的储存。

关键词: 全钒氧化还原液流电池（VRB）, 电解液, 添加剂, 木质素磺酸钠