Analysis of the reason of lithium battery blasting

When the capacity of the negative electrode opposite to the positive electrode is lacking, or there is no capacity at the base, part or all of the lithium generated during charging cannot penetrate into the interlayer structure of the graphite of the negative electrode, and will precipitate on the surface of the negative electrode to form protruding branches. In the next charge, this protruding part more simply constitutes the precipitation of lithium. After tens to hundreds of cycles of charging and discharging, the dendrites will grow up and eventually pierce the barrier paper, causing internal short circuits. The battery cell discharges rapidly, causing a lot of heat to burn out the barrier, and form a greater short-circuit phenomenon. High temperature will cause the electrolyte to analyze into gas, and the negative carbon and barrier paper will burn, forming an internal pressure that is too large. When receiving this pressure, the battery cell will burst. Excessive moisture content. Moisture can react with the electrolyte in the battery cell to produce gas. When charging, it can react with the generated lithium to generate lithium oxide, which causes the capacity of the battery cell to be lost, and it is easy to overcharge the battery to generate gas. , The analysis voltage of water is low, it is easy to analyze the generated gas when charging, when this series of generated gas will increase the internal pressure of the battery, when the outer shell of the battery is unacceptable, the battery will burst. The internal short circuit is caused by the internal short circuit phenomenon, the large current discharge of the battery cell generates a lot of heat, which burns out the barrier, and constitutes a larger short circuit phenomenon, so that the battery core will have a high temperature, causing the electrolyte to analyze into a gas, which constitutes an internal pressure. When the shell of the battery cell cannot accept this pressure, the battery cell will burst. When the upper glue is laser welded, heat is conducted to the positive ear through the shell, making the temperature of the positive ear high. If the upper adhesive paper is not separated from the positive ear and the barrier, the hot positive ear will burn out or shorten the barrier paper, forming the inner part. Short circuit, which constitutes blasting. When the customer spot welds the negative ear with high temperature adhesive paper, the heat is conducted to the negative ear. If the high temperature adhesive paper is not attached properly, the heat on the negative ear will burn out the barrier, causing an internal short circuit and blasting. The bottom glue does not completely cover the bottom. When the customer spot welding at the bottom aluminum-nickel composite tape, a lot of heat will be generated on the bottom shell wall, which will conduct the bottom of the pole core. If the high temperature adhesive tape does not completely cover the barrier, it will burn the barrier. , Constitute an internal short circuit, constitute a blasting. When the overcharge core is overcharged, the excessive release of lithium in the positive electrode will change the structure of the positive electrode. If too much lithium is released, it will simply not penetrate into the negative electrode. It will also simply form the negative electrode surface to deposit lithium, and when the voltage reaches 4.5V or more At times, the electrolyte will analyze and produce a lot of gas. All of the above may constitute blasting. External short circuit The external short circuit may be caused by improper operation or misuse. Because of the external short circuit, the battery discharge current is large, which will cause the battery core to heat up, and the high temperature will shorten the internal barrier of the battery core or completely destroy it, forming an internal short circuit. Thus blasted. Disclaimer: Some pictures and content of the articles published on this site are from the Internet. If there is any infringement, please contact to delete. Previous: Which one is better for lithium iron phosphate batteries than batteries?