8 misunderstandings in the use of car batteries

1. The battery charge capacity does not match the engine. The rational selection of the battery charge capacity according to the engine type and operating conditions is one of the important ways to improve the economy of the battery and prolong its service life. When the starter starts the engine, the current output by the battery is very large, usually 150A-200A, and the output current is as high as 250A-300A when starting at low temperature (-10℃). If the charge capacity of the battery does not match the engine, and the charge capacity of the battery is too small, when the starting resistance is large, the battery with a small charge capacity will inevitably accelerate the reaction between the active material and the sulfuric acid per unit time and increase the temperature of the battery when the battery with a small charge capacity is violently discharged. High, the electrode plate is bent due to overload, resulting in a large amount of active material falling off, and the electrode plate is damaged early, which greatly shortens the life of the battery. If the charge capacity of the battery is too large, although the above-mentioned problems will not occur, the active material can not be fully utilized and the economy of the battery will decrease. Therefore, the charge capacity of the battery must match the engine. Generally, the selection of battery charge capacity should be based on the power, voltage of the starter and the load of the electrical equipment. 2. Parallel and mixed use of batteries. When starting the engine, some drivers connect a fully charged battery in parallel for common use due to insufficient storage of the original battery. In fact, a battery that is fully charged in parallel will charge the battery with insufficient charge with a large charging current, which will easily cause the active material of the plate to fall off and affect its service life. At the same time, the parallel connection of the batteries cannot supply a large starting current to the starter, which is even more unfavorable to the starting of the engine. The correct method should be to remove the battery with insufficient charge, replace it with a fully charged battery, and then start the engine. Third, the battery is used in series and mixed in the battery, and sometimes new and old batteries are used in series. As everyone knows, this approach will shorten the service life of the battery. Because there are more chemical reaction substances in the new battery, the terminal voltage is higher, and the internal resistance is small (the internal resistance of the new 12V battery is only 0.015-0.018); while the terminal voltage of the old battery is low, and the internal resistance is larger (the internal resistance of the 12V old battery is only 0.015-0.018). Resistance is above 0.085). If the new and old batteries are mixed in series, then in the charging state, the charging voltage at both ends of the old battery will be higher than the charging voltage at both ends of the new battery. As a result, the new battery is not fully charged and the old battery is already charged too high; in the discharged state Because the charge capacity of the new battery is larger than that of the old battery, the result is that the old battery is over-discharged and even the old battery is reversed. Therefore, the new and old batteries must not be mixed. A warm reminder from the author of Baibai Safety Net: storage batteries with different charge capacities cannot be mixed in series, because when two storage batteries with different charge capacities are used in series, the batteries with small charge capacity will often be overcharged or discharged, shortening their service life. 4. Diesel vehicle battery cell damage continues to be used. Because the diesel engine compression is relatively large, the required starting torque is also large, so the general diesel engine uses 24V voltage to start to increase the specific power of the starter, but the generator and the whole vehicle The electrical equipment still uses 12V voltage, so the diesel vehicle circuit is equipped with a voltage conversion switch. When starting, the conversion switch connects two 12V batteries in series and supplies power with 24V voltage. When in the non-starting state, the conversion switch restores the two batteries. To work in parallel to meet the requirements of 12V voltage. However, when a single cell of one of the batteries is damaged, some drivers will short-circuit it and continue to use it. In this way, due to the unequal voltage of the two batteries, a larger discharge current and charging current will be caused, resulting in damage to the battery and generator. Therefore, if the battery cell on diesel vehicles is damaged, it should be replaced or repaired immediately, and the single cell battery cannot be used after short-circuiting. V. Ignore the dredging of the vents. The battery will produce hydrogen and oxygen during the charging and discharging process, especially when overcharged, the water is electrolyzed and a large amount of hydrogen and oxygen will appear. The vent hole on the battery filling hole cover is used to dissipate these gases. Normally, if the vents are ignored, the vents will be blocked, and the heat and gas generated during the chemical reaction of the battery will not be dissipated, which will cause the internal temperature and pressure of the battery to continue to rise, and eventually cause the battery to explode. Therefore, in daily maintenance, attention should be paid to dredging the vent holes to prevent dirt from blocking the vent holes. 6. The main power switch is installed on the live-wire end of the battery. Some domestic cars do not have the main power switch installed when they leave the factory. For safety and convenience, some drivers and maintenance personnel have installed a manual main power switch, but mistakenly installed the main power switch on the live wire end of the battery, because the power supply of most cars is the negative ground, so this is not only It does not play a precautionary purpose, and it will cause new insecurity factors. 7. Blindly install the main power switch on the EFI vehicle. For safety reasons, some drivers install the main power switch on the EFI vehicle. This approach is very harmful. Because this kind of car is equipped with a computer, it has very strict requirements on the power supply voltage, and the battery can not only store electric energy in the circuit, but also absorb the surge voltage and pulse high voltage in the circuit. 8. Blindly cut off the main power switch. The main power switch on some cars controls the on and off of all electrical equipment. During the operation of the car, once the electrical equipment or circuit fails, the main power switch can be quickly cut off to prevent the failure from expanding. Disclaimer: Some pictures and content of articles published on this site are from the Internet, please contact to delete if there is any infringement. Previous: What is the fire protection strategy for lithium-ion batteries?