Lead-acid battery maintenance and precautions
1. When the battery is charged or discharged, the battery liquid level changes:
1. When the battery is discharged: the battery liquid penetrates into the pores of the battery plate, so the battery liquid level will
decline.
2. When the battery is charging: The battery liquid is discharged from the pores of the battery plate, so the battery liquid level will rise.
2. About the loss of battery fluid:
1. When the battery is charging, especially near the gasification stage (Cassing Condition), the electrical reaction is that the water of the battery liquid is electrolyzed. The gas of hydrogen (H) and oxygen (O) overflows, so that the battery liquid capacity decreases and the concentration increases.
2. When the battery is discharged, the above reaction will also occur, but it is not strong when charging, but when the large current is continuously discharged, the above reaction also loses water very strongly.
3. In a fierce electrochemical reaction, if the battery liquid level is too high, the discharged gas will splash and overflow with the battery liquid, so that the battery liquid level drops (among which the sulfuric acid H2SO4 in the battery liquid follows the battery liquid Overflow and loss). If supplemented pure water is used to maintain the liquid level, the liquid level of the battery liquid will be changed (that is, the specific gravity of the battery liquid is insufficient). Since the battery liquid splashing and overflowing conditions of each unit are different, the specific gravity between the unit cells after water replenishment in this way is inconsistent, forming a potential difference between the unit cells, thereby affecting the performance of the battery. Therefore, we must strive to avoid this situation in battery use.
3. Why should we add pure water:
1. Regardless of how the battery fluid level changes at any time, the battery fluid must be submerged in the polar plate (the polar plate must not expose the battery fluid), so that it can fully play its design requirements (capacity). The battery capacity is related to the area of the battery fluid contacted by the battery plate.
2. The battery should maintain the consistency of the battery fluid and the consistency between the unit cells during operation. Otherwise, there is a potential difference between the individual cells, causing a circulating current and affecting the efficiency of the battery pack. The battery voltage is related to the concentration of the battery fluid.
3. Correct water replenishment has an important impact on the battery's performance and service life and can reduce and reduce sulfation.
4. How to add water:
1. Must be carried out within 1-2 hours after the battery is fully charged
2. After the battery is used, the measured liquid level (based on the splash-proof plate) should still be detectable (make sure that the battery plate is not exposed during the last charge and discharge cycle).
3. After replenishing water, the liquid level should be 5-10 mm higher than the splash plate, but not too high (based on the splash plate).
4. After several charge and discharge cycles, when the battery liquid is charged until it can no longer be recharged, the specific gravity of the battery liquid is measured. If the specific gravity is too low or the specific gravity of each unit cell is inconsistent, sulfuric acid should be added. Re-adjust the specific gravity to (1.27-1.29) G/CM3 (to make the specific gravity of each unit battery close to the same). After adjustment, recharge to make the battery liquid even. This item should be carried out by professionals.
5. Matters needing attention:
1. In normal use, within a charge and discharge cycle, the moisture loss of a unit cell is about 4ml/100Ah. Example: A 500Ah unit battery should be supplemented with approximately 20 ml of pure water.
2. After replenishing water, the liquid level of the battery liquid must not exceed 10mm of the splash plate, the reasons are: A. If the liquid level is too high, the battery liquid capacity will contact the aluminum row welded between the battery plates, which will form ionic pollution of the battery liquid, which will strengthen the battery pack discharge and damage the battery capacity and life.
B. Excessive liquid level will cause the battery liquid to splash and overflow during the electrochemical reaction, resulting in a decrease in the battery liquid concentration, thereby reducing the battery capacity and battery voltage. And the splashed battery fluid will cause corrosion to the car body and battery.
3. If the battery liquid level is insufficient, the upper part of the battery plate will be exposed to the battery liquid when the battery is in use, thus reducing the area of the battery plate participating in the electrochemical reaction and thereby reducing the capacity of the battery.
