Na2S2O3对镍钴电池负极材料电化学性能的影响

Effect of Sodium Thiosulfate on Electrochemical Properties of Nickel-cobalt Battery Anode Materials

通过向镍钴电池的电解液中加入不同浓度Na2S2O3,并研究了其对镍钴电池负极材料电化学性能的影响,采用SEM和XRD分析了沉淀产物的微观形貌和结构。结果表明,通过对钴电极的充放电性能测试发现,当Na2S2O3浓度为0.04mol/L时,Co电极的最大放电容量高达411.1mA·h/g,当Na2S2O3浓度0.02mol/L时,Co电极的循环稳定性最好,其容量保持率为86.16%,比未加Na2S2O3时的容量保持率高出30.71个百分点。结合循环伏安特性曲线(CV)和交流阻抗图谱(EIS)分析得知,Na2S2O3能够有效抑制CoOOH的形成,提高活性物质的利用率,从而实现放电容量和循环稳定性的提高。

The effects of sodium thiosulfate(Na2S2O3)on the electrochemical properties of nickel-cobalt battery anode materials were investigated with different concentrations of Na2S2O3 to the electrolyte.The morphology and structure of precipitum were analyzed by scanning electron microscopy(SEM)and X-ray diffraction(XRD).Chargedischarge measurements show that the Co electrode has a maximum discharge capacity of 411.1 mA·h/g with0.04 mol/L Na2S2O3 additive in the electrolyte.When the concentration of Na2S2O3 is 0.02 mol/L,the stability of Co electrode is the best with a retention rate of 86.16%,30.71 points percent higher than that without Na2S2O3.The results of cyclic voltammetry(CV)and electrochemical impedance spectroscopy(EIS)show that the addition of Na2S2O3 can effectively inhibit the formation of CoOOH,and then improve the utilization rate of active materials,thereby achieve an improvement in discharge capacity and cycle stability.