新型粘结剂海藻酸钠在锂硫电池中的应用研究

摘要

Sodium alginate was employed as binder of positive electrode for lithium-sulfur battery.Electrochemical stability of sodium alginate and structure,morphology and electrochemical properties of the sulfur cathode with sodium alginate as binder were investigated via CV,El,SEM methods.The results show that the electrochemical stability window of the sodium alginate is 1-5 V,structure and morphology of composite sulfur cathode is stable during charge-discharge,the impedance of the cathode is decreased by 34.8％ and charge-discharge and cycle performance are also significantly improved compared with the commonly used polyvinyl fluoride (PVDF) binder.%以海藻酸钠作为锂硫电池正极粘结剂,通过循环伏安(CV)、扫描电镜(SEM)、交流阻抗(EI)、恒流充放电等方法,分析了海藻酸钠(SA)作粘结剂的复合硫正极的结构形貌、电化学性能及电化学稳定性.结果表明,海藻酸钠的电化学稳定窗口为1～5V;充放电过程中,硫正极的结构形貌稳定;与常用的聚偏氟乙烯(PVDF)粘结剂相比,正极片的阻抗降低了34.8％,充放电性能及循环性能均显著改善.