What are the reasons for the vulcanization of lead-acid battery plates?
2022 Jul 14 By admin 0 comment
  1. The reason for the vulcanization failure of the pole plate

(1) The initial charging is insufficient or the initial charging is interrupted.
(2) After the battery is discharged, if it is not charged in time or is often insufficiently charged within 24 hours, and the idle battery lacks due regular charging, a part of lead sulfate that has not been decomposed and reduced will remain on the electrode plate, which will be converted into sulfate over time, so that the Plate vulcanization.
(3) The battery is often discharged with high current and overdischarged, and it is in deep discharge with low current for a long time. The long-term self-discharge of the battery that is placed on the shelf will cause sulfate to be generated in the depth of the plate, resulting in serious vulcanization of the plate.

(4) Electrolyte is not replenished in time due to evaporation, decomposition and loss of distilled water, resulting in the long-term exposure of the electrode plate to the outside of the electrolyte solution. Because it has adhered and deposited sulfuric acid solution, the electrode plate will be vulcanized.
(5) The sulfate of the battery falls off the plate due to vibration, which promotes the increase of sulfate in the electrolyte, and it will re-attach to the surface of the plate in a new way, forming a layer of hard and thick white particles, causing The plate is fully vulcanized.

(6) Impure electrolyte is used. When the electrolyte is reduced, sulfuric acid solution is added. If the density of the electrolyte is too high for a long time, it will lead to vulcanization of the electrode plate. The vulcanization of the pole plate formed by this reason often leads to the scrapping of the battery in about a year.
(7) Heat will be generated when the electrolyte is prepared, and it must be cooled to 10℃-30℃ before it can be poured into the battery. Otherwise, hot electrolyte will accelerate plate vulcanization.

(8) When the battery is discharged, the positive and negative plates will produce lead sulfate, causing vulcanization. (Want to learn more about the causes of battery vulcanization: welcome to visit Tycorun Battery to discuss together.)
When the battery is charged, because the positive plate is connected to the positive pole of the power supply, the oxidation of the positive electricity can easily convert the lead sulfate on the positive plate into lead dioxide. However, the situation of the negative plate is different. It is connected to the negative pole of the charging power supply, so it does not have the characteristics of the positive plate. In the case of long-term insufficient charging or frequent over-discharging and long-term power loss, the lead sulfate on the surface will gradually become a dense and hard sulfate, which is difficult to dissolve and electrolyze in the negative electrode, but can block the micropores of the negative plate. It hinders the normal penetration of the electrolyte into the electrode plate, so that the active material in the inner layer of the electrode plate cannot be in good contact with the sulfuric acid and conduct a perfect reaction, which directly leads to the inability to continue charging. This is not only the main reason for the reduction of battery capacity and shortened life, but also the principle of vulcanization of the electrode plate.
The above shows that the vulcanization of battery plates mainly refers to the negative plates.

battery vulcanization
battery vulcanization
  1. Judgment method of plate vulcanization

The method of judging the vulcanization of the plate is explained below by taking a 12V battery as an example.
(1) When charging with a constant voltage of 14.5V, the charging current begins to have a charging current and gradually increases, but soon gradually decreases from a certain value, it can be judged that the battery plate has been vulcanized.
(2) When the battery is charged with a constant voltage of 14.5V, if the charging current is small or even zero at the beginning, it can be judged that the electrode plate of the battery has been vulcanized.
(3) When charging with a constant current of C20, the battery shows a fully charged voltage value at the beginning, and then the voltage gradually decreases, and it can also be judged that the battery plate has been vulcanized. And the higher the starting voltage, the more serious the plate vulcanization.
(4) If there are white particles of sulfate and white felt-like separator on the electrode plate from the battery filling hole, it means that the battery electrode plate has been vulcanized.

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