立体构造石墨烯材料对铅酸蓄电池负极性能影响的研究

以具有高比表面积、优良的导电性和高稳定性的立体构造石墨烯材料（stereotaxically-constructed graphene, SCG）作为添加剂,加入到铅酸蓄电池负极活性材料中,通过XRD、SEM和电化学测试手段系统地分析其对电池性能的影响. 结果表明,SCG材料可以抑制硫酸铅晶体的生长,促进硫酸铅向海绵状铅的转变,延缓不可逆硫酸铅在负极的积累,在0.1 C放电速率下,添加有SCG材料的铅酸蓄电池的负极活性材料的初始放电容量为173.8 mAh·g ^-1,比未添加碳材料的(151.6 mAh·g ^-1)高14%. 在高速率部分荷电状态(HRPSoC)条件下, 添加SCG材料的电池循环寿命达到10,889圈,是未在负极活性材料中添加碳材料的电池的循环寿命的303%. 这些结果验证了立体构造石墨烯材料对铅酸蓄电池的积极影响,展现了其在铅酸蓄电池中的良好的应用前景.

Effect of Stereotaxically-Constructed Graphene on the Negative Electrode Performance of Lead-Acid Batteries

With the advantages of high ratio surface area, excellent conductivity and high stability, the stereotaxically-constructed graphene (SCG) material was added to the negative active material (NAM) of lead-acid battery for improving battery performance. XRD, SEM and cyclic voltammetry tests were carried out to analyze the influence of SCG on negative active material. It is found that the conversion efficiency of lead sulfate to lead in the negative active material added with SCG material was higher than that of control group, and the particle size of the lead sulfate obtained after the discharge reaction was smaller, which are favorable factors for inhibiting the irreversible sulfation of the negative active material. At the discharge rate of 0.1 C, the initial discharge capacity of the NAM with SCG added was 173.8 mAh·g ^-1, being 14% higher than that of the NAM without carbon adding (151.6 mAh·g ^-1). The cycle life under the high-rate partial-state-of charge (HRPSoC) state reached 10,889 cycles, which was 303% longer than the control one. Finally, for explaining the benefits of SCG materials in lead-acid batteries, possible mechanism is proposed as below: SCG material has a porous structure and excellent conductivity, which allows it to build a conductive network in the NAM and provides an ion channel for the electrolyte, thereby, reducing the ohmic resistance of the negative plate, improving the efficiency of material exchange in chemical reaction as well as the charge acceptance ability of the battery. Furthermore, LSV and EIS tests confirmed that the addition of SCG material would not cause serious hydrogen evolution reaction to the NAM, which can reduce the loss of electrolyte and maintain the stability of the battery. These results verify the positive effect of SCG on lead-acid battery, and show potential application prospect in lead-acid battery.