Three dangerous consequences of lithium battery short circuit and introduction of explosion-proof measures

The safety problem of lithium battery is caused by short circuit. If accidentally have left over from the impurities in the electrolyte, the incorrect use and shelve will appear in the battery heating, these impurities caused by the "static" to "move", which is likely to cut across the electrodes used to prevent contact with in the process of movement of the diaphragm to cause short circuit, short circuit may cause the three consequences, it depends on the severity of the shorted.

1. Leakage: When the temperature of the lithium battery rises slowly, the outer shell gradually dissolves, and the protective layer does not protect, resulting in leakage of corrosive electrolyte.

2. Explosion: The temperature of the lithium battery rises rapidly. Since the outer casing does not melt gradually when the temperature rises slowly, the internal space of the battery is insufficient to accommodate the inflation gas under heating, and the battery container explodes due to excessive pressure.

3. Spontaneous combustion: the spark generated by short circuit will ignite the electrolyte instantaneously. This is because the electrolyte is composed of flammable liquid.

Although the reports of spontaneous combustion and explosion of lithium batteries are not uncommon, they are negligible in proportion. This is because lithium battery manufacturers have taken into account these safety hazards and avoided this situation in several levels. .

First of all, measures have been taken from the internal structure of the lithium battery. The quantity and size of the impurities of the qualified lithium battery are controlled within a small range, and the probability of breaking the diaphragm is extremely low.

Secondly, for lithium-ion batteries for portable products, such as laptop batteries, there is a multi-level protection mechanism, even in the case of abnormal charger and computer and the lithium battery can be automatically protected.

Third, the warning measures when using. Which including: original lithium battery, original charger, suitable ambient temperature, not self-modifying battery.

However, the above three aspects of security measures are not necessarily 100% guaranteed. For example, the protection mechanism of lithium batteries may degrade after a long period of use, resulting in overcharge, over discharge, over current, overheating. The sensitivity is reduced, so that there is still a potential safety hazard in the above state. In general, the theoretical accident probability of lithium batteries is only a few hundred thousandths or one millionth of a million, which is a mature product.

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