| The use of renewable energy and energy storage system with intermittent and unstable characteristics is the core means to optimize the energy structure, ease the pressure and improve the quality of power. Methyl sulfonic acid lead flow battery with its simple structure, low cost,strong weatherability and easy recycling and other advantages, is expected to become power type storage million times long life cycle and MW capacity system. During the charging process of lead sulfonic acid lead battery, it is easy to cause the positive and negative poles of the battery to be short circuited due to the solubility of Pb2+ in the form of dendrite morphology. Based on this, this paper based on the 1.0mol/LH+ and 0.7mol/LPb2+ as electrolyte by adding metal ion additive to the electrolyte (Sn2+), organic additives ten alkyl three methyl ammonium hydroxide (HDTAH)inhibited the battery negative dendrite growth and improve the cycle performance of battery test system, using cyclic voltammetry, LAND battery (CV), chronoamperometry method (CA) and linear scanning (LSV) combined with electrochemical methods such as scanning electron microscopy (SEM), X ray diffraction (XRD), X ray photoelectron spectroscopy (XPS) to explore mechanism of additive inhibition of battery cathode dendrite and the rule of influence of power storage efficiency and cycle life of the surface detection system get the following results:Primary,when Sn2+ was used as electrolyte additive,the concentration of 0.8mmol/L -1.0mmol/L, which resulted in the formation of lead in the negative electrode of the battery, and the density of lead particles was compact. The mechanism using Sn2+ additive inhibits negative dendrite morphology in the electrolyte: 1) to promote the deposition of Pb increased Pb/Pb2+couple power on the reversible and Pb2+ diffusion coefficients in the electrode surface; 2) changing mode of crystallization of lead,by the "three-dimensional instantaneous nucleation" into "three dimensional continuous nucleation" lead the nucleation density increased; 3) lead and tin co-deposition of PbSn solid solution before the lead in (111) the growth, thus inhibiting the negative lead dendrite morphology. The addition of Sn2+ to the electrolyte can improve the efficiency 90% and the energy efficiency of the battery 86.4%. The service life of the battery can be increased by 2 times, and the optimum adding amount of Sn2+ is 0.8mmol/L.Secondly, HDTAH as electrolyte additives,the concentration of 1.5mmol/L ?2.5mmol/L, the change of the negative pole of the dendrite morphology, so that the lead in the cathode deposition more smooth, dense, thereby improving the discharge capacity. Add HDTAH electrolyte: 1) adsorbed on the electrode surface, improve the cathodic polarization of the battery, the negative role of grain refinement to lead; 2)can inhibit the lead electrodeposition of the anode, but Pb/Pb2+ couple of reversible increased; 3) HDTAH adsorption of lead grain growth point, changing the growth direction of lead; 4) the lead in the deposition of nuclear "negative to three-dimensional instantaneous, so as to improve the nucleation density of lead but the diffusion coefficient decreased; 5) make the charging efficiency of the battery to improve the average energy efficiency of 89% and 80%, about the battery cycle life than batteries without additives added 190 times.and the optimum adding amount of HDTAH is 0.8mmol/L. |
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