| In this paper, The VRLA battery which was used in railway passenger cars was designed, its name was TM-450,and Pb-Ca-Sn-Al-Bi grid alloy was carried out a preliminary study. It chosed railway passenger power as the background, designed a continuous uninterrupted power supply.First,it introduced an overview of the classification of batteries, and then introduced an overview of the VRLA battery technology development and grid alloys research process. It outlined the structure of lead-acid battery It focused on expounding battery chemistry principle and grid corrosion principle, including the positive electrode reaction and negative electrode reaction, oxygen cycle principle, gassing reaction.It simulated the real storage, Capacity, grid, separator, electrolyte, battery container, lead paste, safety valve, terminal,Poles and other components was designed . using high-quality raw materials, advanced process formulations to meet the national quality standards and a company's corporate standards.Linear sweep voltammetry, cyclic voltammetry, AC impedance method, anodic polarization, cathodic polarization and other methods commonly used in electrochemical analysis, and hardness testing were studied the Al-Pb-Ca-Sn-Bi alloy ,and finally reached the following conclusions.1. With the increase in calcium content, the corrosion rate was accelerated. Therefore, the calcium content of alloys should be controlled at a low concentration range (≤0.1%).2. With the increase in sin content , oxygen over-potential, hydrogen over-potential increased, battery maintenance-free performance has been improved; when tin content is greater than 2.0%, with the tin content increased, the oxygen evolution voltage electrode has little changed,in the same time, the alloy polarization potential was increased, which may lead to passivation phenomena in the charging and discharging process, causing battery failure; adding too high tin in the lead-calcium alloys ,alloy hydrogen over-potential will be reduced slightly, the battery maintenance-free performance slightly inferior.3. With the increase of tin content in the alloy ,the hardness first increases and then decreases, when the tin content is 1.2% , the hardness of was the Pb-Ca-Sn-Al alloy the maximum.4. As the r (tin-calcium ratio)value increases, it generated less amount of Pb(Ⅱ) when generating membrane, the growth of passive film was restrained obviously , impedance of anodic film is also gradually increasing simultaneously. But when the r is rising, the inflence of the restraining was improved slowly,impedance have stabilized. When r probably reach 15, the alloy tends to influence the passive film stability, and therefore range appropriate of the r was: 15≥r≥9. The preparation of alloys, it can first determine the Ca content, and then select an appropriate r, the Sn content will be calculated. 5. With the increase in bismuth content, the hardness slightly increased, but the rate of increase is not very clear. When the time extended, hardness of the alloy was slightly increased , but the rate of increase was not obvious.6. With the increase in bismuth content, the rate of the hydrogen and oxygen precipitation on the Pb-Ca-Sn-Al alloy surface was promoting, the performance of maintenance-free battery was decreased. Therefore, the efficiency of the battery sealing reaction was at low.7. With the increase in bismuth content,the reduction current of PbO·PbSO4 was lessened, so bismuth was restrained Pb (Ⅱ) anodic film to grow.8. With the increasing content of bismuth, the reaction impedance of the Pb-Ca-Sn-Al-Bi alloy has decreased gradually.
|
PDF Full Text Request