Interpretation of the cause of the explosion of lithium-ion battery charging in electric vehicles

Interpretation of the reasons for the explosion of lithium-ion battery charging for electric vehicles 1. Insufficient capacity of the negative electrode of the lithium-ion battery When the capacity of the negative electrode of the positive part of the lithium-ion battery is insufficient, the lithium atoms present during charging cannot be inserted into the interlayer layout of the negative electrode graphite. It precipitates on the appearance of the negative electrode and forms crystals. The permanent formation of crystals in a lithium-ion battery will cause a short circuit. At this time, the battery cell will discharge rapidly, showing a lot of heat, and burning the barrier. High temperature will decompose the electrolyte into gas, and when the pressure is too high, the cell will explode. 2. When the water content is too high, the water can reverberate with lithium and generate lithium oxide, which will cause the capacity loss of the battery cell. It is easy to overcharge the battery cell and generate gas. The analytical voltage of the water is low, which is very difficult during charging. It is easy to analyze the generated gas. When this series of generated gases will increase the internal pressure of the cell, the cell will explode when the shell of the cell cannot be subjected to it. 3. Internal short-circuit The short-circuit of the internal lithium battery cell causes high-voltage batteries to exile, presents a lot of heat, burns out the barrier, and causes a greater short-circuit phenomenon, which will cause the electrolyte to decompose into gas. If the internal pressure is too high, the lithium battery will explode. 4. Lithium-ion battery overcharge When the lithium battery cell is overcharged, too much lithium in the positive electrode will change the layout of the positive electrode. If too much lithium is released, it is easy to be unable to insert into the negative electrode, and it is also easy to cause the appearance of lithium in the negative electrode. When the voltage reaches 4.5V or more, the electrolyte will resolve to produce a large amount of gas. All of the above probably caused an explosion. 5. External short circuit The external short circuit is probably caused by the wrong connection of the positive and negative electrodes. Due to the external short circuit, the electric vehicle lithium-ion battery discharge current is very large, which will cause the battery cell to have a fever, and the high temperature will cause the internal barrier of the battery cell to shrink or completely break down. , Causing an internal short circuit, which exploded. The reason for the fire of electric vehicles is single, and the root cause is the thermal runaway of lithium-ion batteries. Lithium-ion batteries have high energy density, small size, and light weight, which are incomparable to lead-acid batteries. Due to the continuous pursuit of the advantages of lithium-ion battery energy density, the problem of safety has also emerged. The essentials of charging lithium-ion batteries for electric vehicles ●It must be charged with a suitable lithium-ion battery charger. First, insert the output plug of the charger into the battery charging socket, and then insert the charger plug into the mains socket. Investigate the indicator light for charging identification . If the charger is lost, it may be damaged, please buy it from the corresponding dealer. Do not use lead-acid chargers or other forms of chargers for charging. ●It is not possible to charge in the sun in hot weather. It is not possible to charge immediately after driving. The summer is coming. This is especially important. Remember not to charge the electric car in the hot sun, nor to expose the battery to the sun. In the same way, you should stay away from open flames and high-temperature heat sources, whether it is normal or when charging. ●It’s better to charge the lithium-ion battery of an electric vehicle for the first time. It’s better to charge it for a longer period of time, usually 8-12 hours. ●In the process of utilization, it is necessary to prepare and master the charging time and frequency of the lithium-ion battery of electric vehicles according to the actual environment, that is, the environment in which you usually use the frequency and mileage of electric vehicles. ●It is necessary to discharge the lithium-ion battery of electric vehicles. It is not suitable to over-discharge, and it is necessary to guard against frequent complete discharge. Over-discharge may bring catastrophic effects to the battery, especially high-current over-discharge, or repeated over-discharge has a particularly large impact on the battery. Disclaimer: Some pictures and content of articles published on this site are from the Internet. If there is any infringement, please contact to delete. Previous: What are the basic advantages and disadvantages of lithium-ion battery electric vehicles?