Address: 2st floor, B Area, Jinbaisheng Industrial Park, Headquarters 2 Road, Songshan Lake Hi-tech Industrial Development Zone, Dongguan City, Guangdong Pr., China.
Editor:ESTL Category:Technical information Release time:2019-08-16 Click volume:254
Before the storage test, I compiled the first four points of the common cause analysis and solution measures for lithium ion. This time I will introduce the remaining three points. What is it? Let’s take a look!
5. Battery explosion
There are several situations in which a battery explosion occurs:
(1) Overcharge explosion
If the protection circuit is out of control or the detection cabinet is out of control, the charging voltage is greater than 5V, causing the electrolyte to decompose, the internal reaction of the battery reacts violently, the internal pressure of the battery rises rapidly, and the battery explodes.
(2) Overcurrent explosion
If the protection circuit is out of control or the control cabinet is out of control, the charging current is too large, so that the lithium ions are not embedded, and lithium metal is formed on the surface of the pole piece, penetrating the diaphragm, and the positive and negative electrodes are directly short-circuited to cause an explosion (rarely occurring).
(3) Explosion when ultrasonic welding plastic case
When the plastic shell is ultrasonically welded, the ultrasonic energy is transferred to the battery core due to the equipment. The ultrasonic energy is so great that the internal diaphragm of the battery is melted, and the positive and negative electrodes are directly short-circuited to cause an explosion.
(4) Explosion during spot welding
When the spot welding is too large, the internal short circuit will cause an explosion. In addition, the positive connection piece is directly connected to the negative electrode during spot welding, so that the positive and negative electrodes are directly short-circuited and then exploded.
Over-discharge or over-current discharge of the battery (above 3C) tends to cause the negative copper foil to be dissolved and deposited on the separator, so that the positive and negative electrodes are directly short-circuited to cause an explosion (rarely occurring).
(6) Explosion when the vibration falls
The inner pole piece of the battery core caused by the vibrating or falling of the battery core is dislocated, and the battery is directly short-circuited and explodes (rarely occurs).
6. Battery 3.6V platform is low
(1) The test cabinet is not sampled or the test cabinet is unstable, resulting in a low test platform.
(2) The ambient temperature is too low, causing the platform to be low (the discharge platform is greatly affected by the ambient temperature)
7. Improper processing
(1) Forcefully move the spot welding positive electrode connecting piece to cause poor contact of the positive electrode of the battery core, so that the internal resistance of the battery core is large.
(2) The spot welding tab is not welded firmly, and the contact resistance is large, so that the internal resistance of the battery is large.Label: Battery overhaul，Common battery failure
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