Maintenance and precautions of lead-acid battery
1、 Changes of battery liquid level during battery charging and discharging:
1. When the battery is discharged: the battery liquid infiltrates into the pores of the battery plate, so the battery liquid level will drop.
2. When the battery is charged: the battery liquid is discharged from the pores of the battery plate, so the battery liquid level will rise.
2、 Loss of battery fluid:
1. When the battery is charged, especially near the gasification condition, the electrical reaction is that the water of the battery liquid is electrolyzed. Overflow with hydrogen (H) and oxygen (o), so as to reduce the capacity and increase the concentration of battery liquid.
2. The above reaction will also occur when the battery is discharged, but it is strong when it is not charged, but the water loss of the above reaction is also quite strong when it is discharged continuously with high current.
3. In the fierce electrochemical reaction, if the liquid level of the battery liquid is too high, the discharged gas will splash and overflow with the battery liquid, so that the liquid level of the battery liquid will drop (in which the sulfuric acid H2SO4 in the battery liquid will be lost with the overflow of the battery liquid). If the liquid level is maintained with make-up pure water, the liquid degree of battery liquid will change (i.e. the specific gravity of battery liquid is insufficient). Due to the different splashing and overflow of battery liquid in each unit, the specific gravity between each unit battery is inconsistent after such water replenishment, resulting in the potential difference between each unit battery, which affects the efficiency of the battery. Therefore, in the use of batteries, we should strive to avoid this situation.
3、 Why replenish pure water:
1. It is required that at any time, regardless of the change of battery liquid level, the battery liquid must be immersed in the electrode plate (the electrode plate shall not expose the battery liquid), so as to give full play to its design requirements (capacity). The battery capacity is related to the area of battery liquid contacted by the battery plate.
2. During the operation of the battery, the proper concentration of the battery liquid and the consistency of the concentration between each unit battery shall be maintained. Otherwise, there is a potential difference between each unit battery, resulting in circulating current and affecting the efficiency of the battery pack. The battery voltage is related to the concentration of battery liquid.
3. Correct water replenishment has an important impact on the efficiency and service life of the battery, and can reduce and reduce sulfation.
4、 How to replenish water:
1. It must be carried out within 1-2 hours after the battery is fully charged
2. After the battery is used, measure the liquid level (based on the splash plate) and it shall still be detected (confirm that the battery plate is not exposed in the last charge and discharge cycle).
3. After water replenishment, 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, charge the battery liquid until it cannot be recharged. Measure the specific gravity of the battery liquid. If the specific gravity is too low or the specific gravity of each unit battery is inconsistent, add sulfuric acid. Readjust the specific gravity to (1.27-1.29) g / cm3 (make the specific gravity of each unit battery liquid close to the same). Charge after adjustment to make the battery liquid uniform, which shall be carried out by professionals.
5、 Precautions:
1. During normal use, the water loss of a unit battery is about 4ml / 100Ah in a charge and discharge cycle. For example, a 500ah unit battery should be supplemented with about 20ml of pure water.
2. After water replenishment, the liquid level of the battery liquid must not exceed the splash plate by 10mm. The reason is: a. the liquid level is too high, and the battery liquid capacity contacts the aluminum row welded between the battery plates, which will form the ion pollution of the battery liquid, so as to strengthen the discharge of the battery pack and damage the battery capacity and service life.
B. High liquid level will cause splashing and overflow of battery liquid during electrochemical reaction, resulting in the decrease of battery liquid concentration, thus reducing battery capacity and battery voltage. And the splashed battery liquid will cause corrosion to the car body and battery.
3. If the liquid level of the battery is insufficient, the upper end of the battery plate will be exposed to the battery liquid when the battery is used, which will reduce the area of the battery plate participating in the electrochemical reaction and reduce the capacity of the battery.
