碱性铝空气电池电极研究

发布时间：2018-06-06 08:02

本文选题：空气电极 + 防水透气膜　；参考：《太原理工大学》2017年硕士论文

【摘要】：空气电极是铝空气电池的核心。作为气体扩散层,防水透气膜的性能对空气电极影响重大。近年来,在碱性铝空气电池空气电极研究中,以活性炭、乙炔黑和PTFE乳液为材料的防水透气膜越来越受人关注,但其材料配比仍没有统一的定论。因此,本文首要目的是匹配碱性铝空气电池空气电极防水透气膜中活性炭、乙炔黑、PTFE乳液三种材料的质量比例,研究各材料对电极性能的影响。铝阳极是铝空气电极的重要部件,阳极泡沫化具有进一步提升碱性铝空气电池性能的潜力,但仍缺少有力的理论依据。因此,本文的另一目的是研究碱性铝空气电池阳极泡沫化对其性能的影响。为了匹配防水透气膜材料,将活性炭、乙炔黑分别与(60wt%)PTFE乳液单独压制成膜,通过形貌分析和透气性测试,确定活性炭、乙炔黑各自与PTFE乳液的匹配质量比例。将活性炭和乙炔黑的混合碳材料与PTFE乳液滚压制成防水透气膜,并根据各自匹配PTFE质量指定混合膜中PTFE乳液的质量,假设混合物制成的防水透气膜中PTFE的质量与所含活性炭、乙炔黑质量线性相关。将混合碳材料制备的防水透气膜应用于空气电极气体扩散层,通过碱性环境下的电化学测试结果对假设进行验证,并根据膜中孔径分布和比表面积大小对匹配结果进行解释。将活性炭筛分成200目、300目和400目三种粒度,分别制成相应的防水透气膜进行研究和比较,以提高实验结果的准确性,同时研究活性炭粒度对膜性能的影响。以所需含量较少的铂碳为催化剂,并以活性炭、乙炔黑、PTFE乳液为主要材料制备催化膜,将防水透气膜材料质量比匹配结果应用于空气电极催化膜中相应材料,忽略催化剂含量对膜防水和透气性的影响,测试由其制备的空气电极的极化特性,验证防水透气膜中材料匹配结果在催化膜中的适用性,以扩大匹配结果的适用范围。为了研究碱性铝空气电池阳极泡沫化的影响,将泡沫铝电极转化为在垂直于电极表面方向上投影面积增加而在平行于电极表面方向上投影面积不变的电极模型,忽略由闭孔引起的电极反应表面与测试对电极之间产生的距离变化的影响。以强碱为电解质,在三电极体系下对竖直和水平方向上三种面积的纯铝片电极进行电化学测试,得到其Tafel极化曲线和电化学阻抗谱图。通过分析比较竖直和水平方向上不同面积铝片电极在碱性电解质中的腐蚀参数,研究竖直和水平方向上铝电极面积变化对电极性能的影响,并根据电极阻抗参数变化解释其原因,进而推导出碱性铝空气电池阳极泡沫化对电极及电池性能的影响,为多孔铝及铝合金阳极在铝空气电池上的应用提供理论依据。
[Abstract]:Air electrode is the core of aluminum air battery. As a gas diffusion layer, the performance of waterproof gas permeable film has a great influence on the air electrode. In recent years, in the study of air electrode of alkaline aluminum air battery, the waterproof and breathable film made of activated carbon, acetylene black and PTFE emulsion has attracted more and more attention. Therefore, the primary purpose of this paper is to match the mass ratio of activated carbon and acetylene black PTFE emulsion in the air electrode waterproof and gas permeable membrane of alkaline aluminum air battery, and to study the effect of each material on the performance of the electrode. Aluminum anode is an important part of aluminum air electrode. Anode foaming has the potential to further improve the performance of alkaline aluminum air battery, but it is still lack of theoretical basis. Therefore, another purpose of this paper is to study the effect of anode foaming on the performance of alkaline aluminum air battery. In order to match the waterproof and breathable membrane materials, activated carbon, acetylene black and PTFE emulsion were pressed separately to form film. The matching mass ratio of activated carbon and acetylene black to PTFE emulsion was determined by morphology analysis and permeability test. The mixture carbon material of activated carbon and acetylene black was rolled into PTFE emulsion to form waterproof permeable film, and the quality of PTFE emulsion in mixture film was determined according to the respective matching quality of PTFE. The mass of PTFE in the mixture was assumed to be the mass of PTFE and active carbon contained in the waterproof permeable film. Acetylene black mass linear correlation. The waterproof permeable membrane prepared by mixed carbon material was applied to the gas diffusion layer of air electrode. The hypothesis was verified by electrochemical test results in alkaline environment and the matching results were explained according to the pore size distribution and specific surface area of the film. The activated carbon was sifted into three sizes of 200 mesh, 300 mesh and 400 mesh, and the corresponding waterproof and breathable membranes were prepared for study and comparison, in order to improve the accuracy of the experimental results, and at the same time to study the effect of the size of activated carbon on the performance of the membrane. The catalytic membrane was prepared by using activated carbon and acetylene black PTFE emulsion as the main materials. The mass ratio matching results of the waterproof and permeable membrane materials were applied to the corresponding materials in the air electrode catalytic membrane. The effect of catalyst content on the waterproof and permeability of the membrane was ignored, and the polarization characteristics of the air electrode prepared by the catalyst were tested, and the applicability of the material matching results in the membrane was verified, so as to expand the applicable range of the matching results. In order to study the effect of anodic foaming of alkaline aluminum-air battery, the aluminum foamed electrode was transformed into an electrode model with an increase in projection area perpendicular to the surface of the electrode and no change in the projection area parallel to the surface of the electrode. The influence of the electrode reaction surface caused by the closed pore and the measurement on the distance between the electrodes was ignored. The Tafel polarization curves and electrochemical impedance spectra of three kinds of pure aluminum sheet electrodes in vertical and horizontal direction were measured by using strong alkali as electrolyte in the system of three electrodes. By analyzing and comparing the corrosion parameters of aluminum sheet electrodes with different areas in the vertical and horizontal directions in alkaline electrolytes, the effect of the area variation of aluminum electrodes in vertical and horizontal directions on the performance of the electrodes is studied. The reason is explained according to the change of electrode impedance parameters, and the influence of anode foaming on electrode and battery performance is deduced, which provides a theoretical basis for the application of porous aluminum and aluminum alloy anode in aluminum air battery.
【学位授予单位】：太原理工大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TM911.41

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