Investigations On Formation Of The Automotive Lead Acid Batteries Plates And Its Performance

Lead-acid batteries have many benefits such as low cost and good performance etc., so they are still widely used as power sources of automobiles, electric vehicle and other industial systems. Among them, the automotive batteries account for the largest by value. The manufacture of lead-acid batteries includes a series of processes, in which the formation step is one of the most important steps where bottle-neck may occur. Formation is the first charge for the plates, therefore, it has an direct effect on the performance of the batteries and its life. And it is well known that the non-uniform current and potential distributions on the plate can obviously affect the active mass utilization, especially for the positive plate. This paper researches on the practical current and potential distributions on the positive and negative plates of automotive batteries in the course of their formation processes by the means of an in situ electrochemical scan, and then studies the influences of the formation and also the additives on the performance of the automotive plates.During the formation, the positive plates with red lead and BaPbO3 additives are easier formed than that without additive, so the current and potential distributions on the plates with additives are more uniform than that without additives in the early stage of the formation. These distributions on the plate with red lead are the most uniform, and the polarization is the smallest. When it is discharged at high-rate, the distributions are also the most uniform at the end of the discharge. This indicates that the positive plate with the red lead has the better discharge performance than the other two kinds of positive plates.The distributions of current density and potential on the negative plates with the radiational or expanded grid designs are more uniform than those on the positive plate. When formed for 8h, because most of paste on the negative plate has converted into lead, the polarization increases and the potential changes greatly, these distributions on the two kinds of negative plates become non-uniform again. At the end of the formation, both current and potential distributions are uniform. However, their distributions on the negative plate with the expanded grid design are a little more uniform. So the formation and the...