Fault diagnosis of the hottest battery

Battery fault diagnosis

common battery faults mainly include charge reduction, self discharge and failure to charge, etc. the fault diagnosis methods are described as follows:

1 Charge reduction

the charge of the battery refers to the amount of electricity that can be supplied by a fully charged battery when the average temperature of the electrolyte is 30 ℃, when the test piece is under pressure, it is discharged continuously for 10 hours with a certain current intensity, and the voltage of a single cell is reduced to 1.7 v. Usually, the product of discharge current value (ampere) and discharge time (hour) is used to express the charge of battery. From this, it can be seen that the charge reduction refers to the fault that the battery can supply less power than the normal power supply after it is fully charged

the main reasons for the decrease of battery charge are as follows: ① the new battery has not been cycled and discharged, or the charge has not reached the specified charge; ② In the case of low engine speed, long-term use of lighting and other electrical equipment will quickly run out of battery storage; ③ The diode of the generator current controller is broken down or has other faults, or the voltage of the DC generator regulator is adjusted too low, so that the battery cannot be charged normally, resulting in battery power loss and reduced charge; ④ The density of the prepared electrolyte is lower than the specified value, or only pure water is added after the electrolyte leaks, so that the density of the electrolyte decreases; ⑤ The density of the prepared electrolyte is too high, or the electrolyte is often added to the battery instead of pure water, and the liquid level in the battery is often too low, resulting in serious vulcanization of the plate

if you feel that the charge of the battery decreases, you can check it with a high-frequency discharge meter. If the voltage of each single cell is above 1.7 V and can be maintained stably for 5S, it indicates that the battery is in good technical condition. If the measured voltage is 1.5 V low, but can be maintained stably for 5S, it indicates that the battery charge is the most insufficient. If the measured voltage drops rapidly below L 5V within 5S, it indicates that the battery is faulty. After determining that the battery has a war barrier, check the density and liquid level of electrolyte first. See Table 1 for the relationship between battery discharge and electrolyte density

if the measured single cell voltage value and electrolyte density value are analyzed comprehensively, the diagnostic conclusion of why the battery charge brightness decreases can be obtained, as shown in Table 2

table 1 Relationship between battery discharge and electrolyte density:

2 The battery discharges by itself:

the battery that has been fully charged or in good use will lose power after 1 ~ 2 days, and the headlamp will not light up when turned on. The sound of the electric horn is weakened or even small. It can be regarded as the battery discharging itself. There are two main reasons: first, the battery separator is broken down or damaged, and impurities such as metal dust are mixed in the electrolyte. Or there are too many foreign matters deposited at the bottom of the battery slot, causing the internal short circuit of the battery; Second, the battery shell is too dirty or too much electrolyte overflows in the bumps, causing a short circuit between the cover and the pile head

first check whether the battery surface is sold out and whether the electrolyte overflows too much to form a conductive layer. Then check whether there is poor contact between the pile head and the wire, or poor grounding. The diagnosis method is: disconnect the power switch, remove the negative terminal wiring of the battery, mark it on the pole. High efficiency transmission and automobile electrification are the driving forces to promote the growth of special materials in various fields of the automobile. If there is a spark at this time, it indicates that there is a short circuit inside the battery, which should be disassembled for maintenance

3. The battery cannot be charged

the battery cannot be charged refers to that the voltage of the battery rises slowly after a long time of charging under the condition that the generator and the transmission part are working normally

the main reasons for the failure of battery charging are as follows: ① the connector in the charging line is loose and rusted, and the contact is small and good, which increases the resistance and reduces the current intensity; ② Rectifier failure or diode short circuit; ③ The battery plate is vulcanized, so that its surface is attached with its classification level. The standard is to judge the original GB8624 ⑵ 006 inspection as grade A1 and A2 corresponding to noncombustible grade A; The original GB8624 (2) 006 was tested and judged as grade B and grade C corresponding to grade B1, which was inflammable; According to the original GB8624 (2) 006 inspection, the corresponding level of D and E is combustible B2; According to the original GB8624 (2) 006 inspection, the white lead sulfate grains with poor conductivity corresponding to grade B3 of grade D and grade E. This kind of coarse grain is easy to block the grid hole of the electrode plate, making it difficult for the electrolyte to penetrate into the electrode plate to participate in the chemical reaction, and reducing the area of the electrode plate to participate in the chemical reaction; ④ Due to the adoption of large current to allow the battery to charge or discharge the battery, or the density of electrolyte is too high, the quality of our machine is large and the liquid level is not high enough, the battery plate is damaged

when diagnosing, first check whether each connector is loose or rusted, whether the electrolyte level is too low, and whether the rectifier has faults, and then judge whether the electrode plate is vulcanized according to some phenomena during charging. If the temperature of electrolyte rises quickly during charging, or the charging time is not long, the electrolyte will produce a large number of bubbles, but the voltage does not rise with it, it indicates that the electrode plate has been vulcanized. If the battery plate is slightly vulcanized, it is generally difficult to detect. In case of serious vulcanization, a layer of white substance can be seen on the electrode plate from the liquid filling port, and the voltage of each single cell cell rapidly rises to more than 2.8V during charging. Then the voltage drops again and rises slowly. At the end of charging, the voltage does not exceed 2.8V. During charging, the temperature of electrolyte is higher, but the density rise is not obvious. After charging, when checking the amount of charge with 20h discharge rate, it is much less than that of normal battery

for batteries with less serious vulcanization, the method of charging for a long time with low current can be used to eliminate it. The specific method is to charge the battery with a current of 0.2A until the voltage and electrolyte density reach the maximum value and do not increase. Then check the amount of charge with the discharge rate of 20 hours. If it is lower than 85% of the rated charge, carry out 1 ~ 2-shaped charge and discharge cycle again to eliminate the vulcanization phenomenon

for batteries with serious vulcanization, hydrotherapy can be used to eliminate it. The method is as follows: after charging the battery, discharge the battery with a discharge rate of 20 hours. When the single cell voltage drops to 1.75 V, pour out the electrolyte, add distilled water, and then charge the battery with a current of 0.2A. When the density of the electrolyte rises to more than 1.15, suck out part of the electrolyte with a densimeter, add an appropriate amount of distilled water, and continue charging until the density of the electrolyte no longer rises. Then discharge for 1 ~ 2H with 1/4 current of 20 h discharge rate, and then charge and discharge for many times, and the vulcanization of the battery can be eliminated. The density of electrolyte can be adjusted to the specified value for the last charge. If the charge of the battery can reach more than 85% of the rated charge, it can be used. If the effect of hydrotherapy is not obvious, chemical method can be used to remove sulfur. The method is: add 0.1% ~ 0.5% pure potassium carbonate or sodium carbonate to the vulcanized battery electrolyte according to the mass ratio. After 1 ~ 2 times of charging and discharging, the battery charge can generally reach about 90% of the rated charge

4 battery electrolyte loss is too fast

battery electrolyte loss is too fast, which refers to the phenomenon that the battery has insufficient liquid level soon after adding electrolyte. The main reason for this fault phenomenon is that the charging and discharging current is too large, which leads to excessive evaporation or overflow of electrolyte. Or the clapboard is damaged, causing a short circuit of the electrode plate. And the battery shell is broken, causing electrolyte leakage, etc. When checking, contact other fault phenomena of the battery for judgment. First, check whether the battery shell has cracks and whether the electrolyte is excessively lost due to leakage. Secondly, contact the usage to find the reason. Excessive use of lights without charging for a long time will cause excessive battery discharge. If charging with high current for a long time, the water in the electrolyte will grow too fast, which will also cause excessive electrolyte loss. During the inspection, eliminate all kinds of traps that lead to the failure

if no abnormality is found through the above inspection, the battery should be disassembled. Check whether the clapboard is broken down and whether the active substances on the plate fall off too much, so that the positive and negative plates form a path. If this happens, it means that the rapid loss of electrolyte is caused by the internal short circuit of the battery. The battery should be repaired