Analysis of the cause of the fault of lithium battery "seven elements"

With the rapid development of the scientific and technological level, the scope of use and role of lithium batteries have long been self-evident, but in our daily lives, the problem is always endless, and sometimes us, in view of this, thousands of fruit electrons are particularly organized. Cause Analysis and Solutions for Lithium Ions FAQ and Solutions I hope to provide you with convenience. First, the voltage is inconsistent, the individual is low 1. Self-discharge is low The battery is self-discharged, so that the voltage reduction is lower than the other fast, the voltage low can be eliminated by the storage of the inspection. 2. Palectification does not make voltage low When the battery is detected, when the contact resistance or the detection cabinet charge current is inconsistent, the electrical end charge is uneven. In a short time storage (12 hours), the voltage difference is small, but the voltage difference between the long-term storage is large, this low voltage has no quality problem, can be solved by charging. The above-hour measurement voltage is stored after the charge is charged. Second, the internal block is large 1. Detecting device difference If the detection accuracy is not enough or cannot eliminate the contact electrochemistry, the display internal blocking is displayed, and the internal resistance instrument detection should be used. 2. Excessive storage time Lithium batteries are too long, causing capacity loss, internal passivation, and large internal resistance, can be solved by charge and discharging. 3. Abnormal heat caused by internal resistance The battery is processed (spot welding, ultrasonic waves, etc.) to abnormally heat the battery, so that the diaphragm produces a thermally closed phenomenon, and the internal resistance is severe. Third, lithium battery expansion 1. Lithium battery is expanded during charging When the lithium battery is charged, the lithium battery will naturally expand, but generally no more than 0.1 mm, but overcharge can cause electrolyte decomposition, increased internal pressure, and lithium battery expansion. 2. Expansion during processing Generally, processing abnormalities (such as short-circuit, overheating, etc.) have caused internal thermal excessive electrolyte decomposition, and lithium battery expansion. 3. Expand when cycling When the battery is cycled, the thickness increases as the number of cycles increases, but it is basically not increased after more than 50 weeks, and the normal increase is 0.3 to 0.6 mm, the aluminum shell is more serious, and this phenomenon is caused by normal battery reactions. However, if the thickness of the housing is increased or the internal material can be appropriately reduced. Fourth, the battery has power-down phenomenon after spot welding The aluminum-shell battery is below 3.7V after spot welding, generally because the point soldering current is substantially caused by breakdown of the internal diaphragm of the battery, causing the voltage drop too fast. Generally, the spot welding position is incorrect. The correct spot welding position should be welded at the bottom or by marking "a" or "-" side spot, no marking side and the surface is not welded. In addition, it is that the solderable nickel band weldability is too poor, so it is necessary to use a wide current spot welding, resulting in the internal temperature resistant tape, causing the internal short circuit inside the battery. The battery power-down is also partially due to the large discharge of the battery itself. V. Battery explosion There are several cases of generating battery explosions: 1. Overcharge explosion The protection line out of control or detection cabinet is out of control to make the charging voltage greater than 5V, resulting in electrolyte decomposition, and the internal pressure of the battery has rapidly increased rapidly, and the battery exploded. 2. Overcurrent explosion Protecting the line out of control or detection cabinet is out of control to cause the charging current to cause lithium ion without being embedded, and a lithium metal is formed on the surface of the pole, penetrate the diaphragm, and the positive and negative direct short circuit causes an explosion (rarely occurred). 3. Ultrasonic welding plastic housing explosion When the ultrasonic welding plastic housing is transferred to the battery cell due to the equipment, the ultrasonic energy is great to melt the internal diaphragm of the battery, and the positive and negative electrode is shorted, and an explosion is generated. 4. Explosion when spot welding When the spot welding is too large, the internal severity short circuit produces an explosion. In addition, the positive electrode connecting piece is directly connected to the negative electrode when spot welding, so that the positive negative is directly short-circuited. 5. Overprint Battery over-discharge or overcurrent discharge (3C) is easy to dissolve the negative electrode copper foil into the diaphragm to cause the positive and negative short circuit to generate an explosion (rarely occur). 6. Explosion when vibration The battery core is misaligned in the electrical cells caused by the cells caused by vigorous vibration or falling, and the explosion is directly severely short-circuited (rarely occurring). 6. The battery is 3.6V platform 1. The detection cabinet is not yet or the detection cabinet is unstable causes low test platform. 2. The ambient temperature is low, the platform is low (the discharge platform is affected by the ambient temperature) Seven, improper processing (1) Positive electrode connecting sheet is moved by force to cause a poor contact of the cell to cause the battery to block the battery. (2) The spot welding piece has no welding, the contact resistance is large, so that the battery is blocked. Recommend: LiFePO4 Battery Manufacturer Energy storage battery Manufacturer Integrated machine energy storage battery series Manufacturer Lead lithium battery Manufacturer Outdoor Backup Battery Manufacturer Portable outdoor power supply Manufacturer Power battery Manufacturer Powerwall LiFePO4 Battery Manufacturer Battery rack Manufacturers Telecom LiFePO4 Battery Manufacturer Wall mounted battery storage Manufacturer China Lifepo4 Battery