Research On The Improvement Of Lead-acid Battery Anode Performance

Lead-acid battery has been used for one hundred and fifty years since it was invented. It cannot be replaced in battery industry for its some unique merits ever since it was invented. With the development of electric vechicles there has appeared another hotspot in the recent years to study lead acid battery. It is of great importace to research on the lead-acid battery as far as the recent situation is concerned. The utilization of lead acid battery active material is universally very low though its technology has reached the maturation. Especially, the utilization of positive active material is much worse. And the performance of the positive pole decides the whole battery performance. In the experiment we try to find out some ways to improve the performance of the positive pole through the study of positive active material and anode grid. We have done a serial of experiments to study the PAM and anode grid with the aids of the measurement such as constant current charge/recharge, cyclic voltammetric measurements, electric impedance spectrum and so on. From the experiment we have found out that the carbon fibre can improve the anode performance when it was used as PAM additive and meanwhile it can have some benefits to the anode life. When its content at 0.2-0.3% in PAM can achieve its best result and under this situation it can improve the utilization of PAM by 5% at different discharge current. Carbon fibre and sulfate sodium is used as complex PAM additive and its effect is better than that of carbon fibre which alone is used as additive. It can get the best effection when carbon fibre content at 0.2% and sulfate sodium content at 2%. At this circumstance it can improve the utilization of PAM by 4-7% than that use carbon fibre only at different discharge current. Sulfate calcium has some bad effects to the performance of the anode when it was used as PAM additive singly. We try to produce foam lead grid in the experiment by a serial of measurments such as found, electroplate. deoxidize and so on. Because of the limitation of experimental conditions we failed to form foam lead grid in the experiment. Copper draw net is used as anode grid and it can improve to some extent the utilization of PAM. Due to human errors in the experiment we have not used the same discharge current density. Thus we cannot compare the experimental data and find out the exact number to be improved. We have made three-dimension electric conduct grid by hand and we have successfully used it as anode grid inlead-acid battery. This kind of three-dimension electric conduct grid can improve the utilization of PAM by 7-9% in different discharge current density and can reduce the plate electrochemical impedance to one tenth of the normal plate. Also this kind of grid can improve the marginal reaction current density in a certain degree. But the grid is so easily corroded that the battery made from it has a very short life. We consider that it will be a very prospective grid for the lead acid battery if the grid can be made of a kind of alloy that is not so easy to be corroded.