Talk about the maintenance of lithium batteries

Talking about the maintenance and vulcanization of lithium batteries is that lead sulfate particles will appear during the charging and discharging of the battery, especially when the discharge is serious. For batteries exceeding 1010 Ah, for example, if a discharge current is used, more lead sulfate particle board materials will appear. Under current conditions, the way the vehicle is used and charged is an irreversible reaction. As time goes by, the particles in the plate will change. Materials will accumulate because they are not conductive particles. The appearance of the internal resistance of the battery is increased, and the capacity is reduced, resulting in a decrease in the capacity of the entire battery, and a high-current discharge capacity (actually expressed as a climbing ability). This phenomenon is called battery vulcanization. Once the battery is vulcanized, it will not only reduce the capacity of the negative plate of the battery, but also aggravate the water loss and softening of the positive plate, which will affect the life of the entire battery. 1) Water treatment For sulfurized batteries, first discharge the battery, pour out the original electrolyte, and inject a dilute electrolyte with a density below 1.10g/cm3, that is, add water to dilute the electrolyte to improve the solubility of lead sulfate. When the current is less than 20h, the battery can be charged for a long time within the range of the liquid temperature not exceeding 20℃~40℃. Finally, when the battery is fully charged, the electrolyte density in the battery can be adjusted to the standard solution concentration with a slightly higher electrolyte. Under normal circumstances, the curing phenomenon can be eliminated, the output can be restored to more than 80%, and the repair can be considered successful. The mechanism of this method is to increase the solubility product of sulfuric acid, reduce the density of the acid solution, reduce the early occurrence of ohmic polarization and delay the water splitting voltage through a small current charging for a long time, and finally gradually reduce or eliminate the vulcanization phenomenon, dissolution and conversion to activity substance. The feature of this method is that it is more suitable for water-filled batteries. The serious curing phenomenon can be treated repeatedly and can be repaired without investing in equipment. The disadvantage is that the process of using sealed batteries is too cumbersome. 2) Shallow cycle high current charging method. Regarding the vulcanized battery, use a high current rate current within 5h. When the battery is charged to the skip overcharge state, control the liquid temperature to not exceed 40 degrees, and then discharge 30%, so that the number of repetitions can reduce and eliminate vulcanization phenomenon. The principle of this method is that the exhaled gas is overcharged to flush the microsulfide salt on the surface of the board, making it desorbed and converted into active substances. The feature of this method is that it can be repaired obviously with regard to mild curing. However, it is not suitable for old batteries, because while the precipitated gas washes the sulfate, it also strongly washes the active material of the anode, which makes the active material soft or even fall off. 3) Chemically repair the vulcanized battery, pour the initial electrolyte, add a mixture of pure water and sodium sulfate, potassium sulfate, tartaric acid and other substances, charge and discharge normally several times, then pour pure water and add a slightly higher density acid to adjust the battery The ability of the standard solution of acid concentration to recover to more than 80% can be considered as a successful repair. In this mechanism, these sulfate complexes are added to form complexes with many metal ions, including sulfide salts. The emerging compounds are unstable in acidic media, and the non-conductive sulfide layer will gradually dissolve back into the solution, dissolving and desorbing the plate. The characteristic of this method is that the repair efficiency is too cumbersome compared with the previous two repair methods. Disclaimer: Some pictures and content of articles published on this site are from the Internet. If there is any infringement, please contact to delete.