铝—空气电池电解质及产物研究

发布时间：2018-12-14 15:36

【摘要】：铝-空气电池比能量高,原材料来源丰富,安全环保,在车载电源、备用电源等方面具有广阔的发展前景。但碱性电解液中铝阳极腐蚀和电池极化现象显著,阻碍了铝-空气电池的商业化进程。对铝-空气电池电解液添加剂进行研究以减小腐蚀,改善铝电极性能具有重要意义。另外通过研究电池放电过程电解液组成变化为降低电池极化提供理论支撑,为放电产物后处理提供方法依据。对放电产物进行研究,探索产物应用价值,提高电池经济附加值,有望开辟铝-空气电池商业化应用新模式。首先,本文首次提出使用锡酸钠和干酪素作为复合缓蚀剂来抑制碱性电解液中铝-空气电池的阳极腐蚀。通过集气实验、电化学实验测试了该复合抑制剂对阳极以及电池性能的影响;并对阳极表面形貌进行研究,尝试对复合缓蚀剂的缓蚀机理做了合理的示意解释。结果表明,复合缓蚀剂的最适浓度为0.05 mol·L-1Na2SnO3和0.6 g·L-1干酪素,可使阳极析氢腐蚀速率降低接近一个数量级。电化学性能测试表明:复合缓蚀剂主要是通过抑制反应的阴极区速率来抑制腐蚀的,同时起到了活化阳极的效果。电池放电结果表明:电池放电性能明显提高,放电容量增加了将近一倍。晶型和形貌组成分析表明:复合缓蚀剂是通过在阳极表面活性位点上的吸附和沉积而起缓蚀作用的。其次,本文使用红外(IR)、核磁(NMR)、拉曼、紫外(UV)等光谱学方法研究了电池放电过程中放电条件的改变对电解液组成的影响。结果表明:Al(OH)4-在放电过程中始终处于优势地位,在其基础上溶液中会产生其他低聚态的含铝酸根离子,但数量较少。碱液浓度、温度和放电电流密度不影响电解液中Al(Ⅲ)的配位数,只对形成的低聚态的含铝酸根的种类和数量产生影响。同时,电解液中四配位含铝酸根占据绝对主导地位,尤其是Al(OH)4-,是导致电池极化加剧的主要原因。最后,在放电过程中电解液组成研究的基础上初步探索了通过放电产物制备高端市场氧化铝的可能性。结果表明:单纯通过改变放电条件可制备出粒度在100nm左右,纯度达到99.99%的高纯超细氧化铝。添加剂如凝胶、纤维的加入则可使粒度降低到50-100 nm。证实了通过铝-空气电池放电来制备高纯超细氧化铝的可能。
[Abstract]:Aluminum-air battery has high specific energy, abundant raw material sources, safe and environmental protection, and has a broad development prospect in vehicle power supply, reserve power supply and so on. However, aluminum anode corrosion and cell polarization in alkaline electrolyte hinders the commercialization of aluminum-air battery. It is of great significance to study the electrolyte additives of Al-air battery in order to reduce corrosion and improve the performance of aluminum electrode. In addition, the study of electrolyte composition during battery discharge provides theoretical support for reducing battery polarization and provides method basis for post-treatment of discharge products. The discharge products are studied to explore the application value of the products and to improve the economic added value of the batteries. It is expected to open up a new commercial application model of the aluminum-air batteries. Firstly, sodium Stannate and casein are used as complex corrosion inhibitors to inhibit the anodic corrosion of Al-air battery in alkaline electrolyte for the first time. The influence of the composite inhibitor on the anode and the performance of the battery was tested by the gas collecting experiment and the electrochemical experiment, and the surface morphology of the anode was studied to explain the corrosion inhibition mechanism of the composite inhibitor. The results showed that the optimum concentration of the complex inhibitor was 0. 05 mol L-1Na2SnO3 and 0. 6 g / L casein, which reduced the corrosion rate of anodic hydrogen evolution by an order of magnitude. The electrochemical performance test showed that the composite inhibitor inhibited the corrosion mainly by inhibiting the cathodic region rate of the reaction and played the role of activating the anode at the same time. The results of battery discharge show that the discharge performance of the battery is obviously improved and the discharge capacity is nearly doubled. The analysis of crystal form and morphology showed that the composite corrosion inhibitor was inhibited by adsorption and deposition on the active site on the anode surface. Secondly, the effects of the discharge conditions on the electrolyte composition were studied by using infrared (IR), NMR (NMR), Raman spectroscopy and UV (UV) spectroscopy. The results show that: Al (OH) _ 4- is always in the dominant position in the discharge process, and on the basis of it, other oligomeric aluminum ions may be produced in the solution, but the quantity is relatively small. The concentration of alkali, temperature and discharge current density have no effect on the coordination number of Al (鈪，

本文编号：2378881