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Analysis of the common faults of the battery
1. A layer of poorly conductive, white, coarse-grained lead sulfate is produced on the electrode plate of the vulcanized battery. When charged normally, it cannot be completely converted into lead and lead dioxide. This phenomenon is called “lead sulfate hardeningâ€. "vulcanization". The coarse grains of lead sulfate block the pores of the plates, making it difficult for the electrolyte to infiltrate and increase the internal resistance, so that the battery capacity is reduced. Sufficient power cannot be supplied at start-up and the engine will not start. When the plate is vulcanized, it has the following phenomena when it is charged: the voltage rises rapidly during charging, prematurely “boilingâ€, and the electrolyte temperature quickly rises above 40°C. When used, the capacitance is significantly insufficient and the voltage drops quickly. There are the following methods for the elimination of plate vulcanization: 1. Over-charging method (suitable for slight vulcanization). The second-stage charging current of the initial charging is continuously overcharged. When the electrolyte generates a large number of bubbles, the specific gravity of about 1.28, you can use. It is advisable to have the individual batteries that have been vulcanized individually charged to eliminate vulcanization. 2. Small current over charging method (applicable to heavier vulcanization). Discharge the battery to the termination voltage at a discharge rate of 10 hours. Discard the electrolyte and add distilled water. Use the second-stage charging current for the initial charge to charge continuously. When the specific gravity of the electrolyte rises to about 1.15, discharge is discharged at a discharge rate of 10 hours. To the termination voltage. Then use the original charging current to charge, until the specific gravity of the electrolyte no longer rises, adjust the specific gravity of the electrolyte to 1.28 and discharge to the termination voltage with a discharge rate of 10 hours. If the battery capacity reaches 80% of the rated capacity, it can be used. If the capacity is still small, it can be repeated as described above until the battery performance returns to normal. 3. Water treatment (suitable for severe vulcanization). After the battery is charged, a discharge rate of 10 hours is discharged, and the voltage of the cell is reduced to 1.8V. Then pour the electrolyte from the battery and immediately add distilled water and let it stand for 1-2 hours. Then charge it with 1/2 of the second-phase charge current, until the specific gravity of the electrolyte reaches 1.12. The charge current is reduced by 1/5 to continue charging until the positive and negative plates begin to appear a large number of bubbles, and the specific gravity of the electrolyte no longer rises, and the charging can be stopped. Then, the discharge current was discharged for 1.5-2 hours at a discharge rate of 1/5 of the discharge rate of 10 hours. Repeat several times until all plates return to normal. Second, the self-discharge battery in the case of not working, the gradual consumption of electricity, said self-discharge. Self-discharge can not be completely avoided, it is generally considered that the consumption of 1%-2% of its own capacity is normal. If it exceeds this value, it is not normal self-discharge. Self-discharge reasons: 1. Plate material or impurities in the electrolyte, so that impurities and the plate or different impurities will produce a potential difference between the formation of a closed "local battery" to generate electricity, so that the battery discharge. 2. The separator ruptured, causing a partial short circuit. 3. The battery cover has electrolyte or water, so that the positive and negative electrodes form a pathway and discharge. 4. The active material falls off, making the plate short-circuit causing discharge. 5. Long-term storage of batteries, sulfuric acid sinks in the electrolyte, so that the proportion of the upper part is small, the lower part of the major proportion, causing self-discharge. To reduce the self-discharge, the electro-hydraulic liquid must strive for purity, and the battery cover should be kept clean during use to avoid short circuit. If the electrolyte is not pure, the battery needs to be discharged with a nominal capacity of 1/10 of the current to a single cell voltage of 1.7 volts. The electrolyte is then poured out, cleaned with distilled water, and replaced with pure electrolyte. Third, the active material from the active material from the reasons: 1. The initial charging current is too large. Since the reduction of the active material of the plate starts from the most conductive grid, when the large current is charged, the lead sulfate is quickly reduced. Therefore, the lead sulfate far away from the grid is less than a chemical reaction due to the volume of the lead sulfate. Because of its large size, it has poor adhesion to the active material that has been reduced inside, so it can easily come off from the pole plate. 2. The current at the end of charge is too large. This will generate a large number of bubbles, violently hitting the surface of the plate, so that a relatively large amount of reduced, relatively loose lead dioxide will fall off. 3. Regular overcharge. Although the over-charged current is not large, the lead sulfate has been reduced to lead dioxide and lead, and the charging current has been used for the electrolyte. At this time, the resulting bubbles are not too much, but the same The surface produces an impact that causes the active material to fall off. 4. The discharge current is too large. At this point, the chemical reaction is intense, which can cause warpage of the plate and cause the active material to fall off. As the active material falls off, the plate will be short-circuited, causing the battery to self-discharge, and the battery must be disassembled and repaired. Fourth, the single-cell short circuit phenomenon is the sudden loss of start-up ability; start-up, the short-circuit cell electrolyte spray. The reason for this is that after a short circuit in a cell, the battery resistance increases, the voltage decreases, and a strong current cannot be supplied. At the same time, a high temperature is generated at the short-circuited point and the electrolyte is rapidly heated and ejected. Common causes of failure: 1. Active material shedding. 2. The use of electrolyte impurities inspection method can use a thin wire to make the grid positive and negative polarity spark, no spark or spark weaker single cell, that is, a short circuit. When confirmed, the first-aid method may use a thick line to short-circuit the positive and negative poles of the short-circuit cell. However, this method can only be used in the summer, and it requires a large starting current in winter. This method cannot be started and must be repaired.