A kind of method that polyaniline and rare earth jointly modify negative plate of lead storage battery

Abstract

The invention discloses a method for preparing and modifying a lead storage battery negative electrode plate by polyaniline. By taking lead dioxide as an oxidizing agent, aniline is oxidized in a sulfuric acid solution to be subjected to a polymerization reaction to prepare polyaniline; the obtained polyaniline is mixed with lead powder to obtain a lead paste material dispersed with polyaniline; by taking the obtained lead paste material as the raw material of the negative electrode active material of the storage battery, a negative electrode grid is coated with the raw material, and coating,filling and curing and drying are performed to obtain a polyaniline-modified negative electrode generation plate; the negative electrode generation plate is subjected to electrochemical formation by taking the rare earth ion-comprising sulfuric acid water solution as a formation liquid; in the electrochemical formation process, a lead compound on the negative electrode generation plate is converted into sponge-shaped lead, and meanwhile, rare earth ions RE<3+> with variable valences are subjected to a reduction reaction on the negative electrode to generate rare earth low-valence material RE<2+>; the generated rare earth low-valence material performs further modification on the negative electrode grid and the negative electrode active material of the negative electrode plate to realize synergetic modification of the negative electrode material by polyaniline and rare earth, thereby improving the performance of the negative electrode plate of the lead storage battery.

Description

technical field [0001] The invention belongs to the technical field of material preparation, in particular to the technical field of lead storage battery negative plate preparation and lead carbon electrode material preparation technology, and specifically relates to a method for jointly modifying the lead storage battery negative plate with polyaniline and rare earth. Background technique [0002] lead battery [0003] Lead-acid batteries have the advantages of simple structure, convenient use, reliable performance, and low price. Therefore, they are widely used in various sectors of the national economy. They have always been the product with the largest output and wide application range in chemical power sources. In terms of R&D and application, the performance of lead-acid batteries has been greatly improved, and the advantages of new lead-acid batteries in some special application fields have become more apparent. As electric mopeds, special electric vehicles, and new-t...

AI Technical Summary

Problems solved by technology

[0031] (1) There is a problem of reduced conductivity of the negative grid during use: coarse lead sulfate dendrites are easily formed on the surface of the negative grid during use, and the resistivity of the lead sulfate dendrites is high. Such thick lead sulfate dendrites are difficult to Charging requires a high charging voltage of the battery, resulting in a decrease in the conductivity of the negative grid

[0032] The electrochemical performance deterioration of the negative electrode active material: when the lead electrode is discharged, the lead loses electrons to form lead sulfate crystals with poor conductivity. The lead sulfate crystals cover the surface of the negative electrode active material. When the lead sulfate reaches a certain thickness, the negative electrode active material will It is difficult to contact with the electrolyte, which hinders the continuous reaction of the negative electrode active material and causes the lead negative electrode to passivate. With the increase of the number of charge and discharge cycles, the discharge capacity gradually decreases; the electrode reaction is preferentially carried out on the electrode surface, and the reaction product lead sulfate is a poor conductor. The internal resistance of the battery increases with discharge, and the reactant H 2 SO 4 It is difficult to diffuse into the depth of the electrode, resulting in more unreacted substances remaining, resulting in a decrease in the utilization rate of negative electrode active materials

[0033] The matching problem of the active material on the negative plate of the lead storage battery and the negative grid: In the existing technology, the negative grid and the negative active material are basically mechanically attached, and there is insufficient contact adhesion, and there are negative active materials during the use of the lead storage battery. shedding problem

However, as the negative electrode active material of the spongy lead of the lead storage battery, especially when the lead storage battery is in the process of fast charging and discharging, more importantly, in the process of dynamic charging and discharging (such as in the process of starting and fast charging of electric vehicles), the most The fast and effective method is to use capacitor technology for fast charging and discharging. Obviously, it is difficult to meet the requirements of fast charging and discharging by using rare earth elements to improve the performance of electrode materials.