Lithium battery explosion

When you buy digital products, you will often notice that the back of the battery will warn the words "Do not throw into the fire, beware of explosions." Now I explain why the lithium-ion battery will explode.

Lithium-ion batteries have the potential to explode because of a process called "thermal runaway" in the internal reaction of the battery. "Thermal runaway" is a positive energy feedback loop process: elevated temperatures cause the system to heat up, and the system heats up to raise the temperature, which in turn makes the system hotter. Thermal runaway is a very common phenomenon, and thermal runaway can occur from a large number of physical and chemical processes in concrete curing (which releases heat) to star explosions (supernova is a product of cosmic thermal runaway).

There are many reasons for the thermal runaway of lithium-ion batteries. For example, when a 9V battery is bridged by a coin at both ends, the tearing of the membrane of the negative electrode and the positive electrode of the isolated lithium ion battery will cause a short circuit, and the short circuit will often cause a thermal breakdown. Lithium-ion battery fires also include: the ambient temperature exceeds 60 ° C, often overcharged, unauthorized modification of the casing.

The size, configuration, and number of cells of the battery can affect the strength of the thermal runaway. Small battery packs (such as those on digital SLR cameras) have only a few battery power supplies, so the chance of thermal runaway propagating from a problematic battery unit to other units is relatively low. The recent Boeing 787 battery problem is another matter: they are packed in a sealed metal box and cannot emit residual heat. As a result, when one battery unit is hot enough to ignite the electrolyte, the remaining battery units will quickly follow up.

But don't worry. Your notebook is not a ticking time bomb. Lithium-ion batteries work safely and reliably as long as they are regularly maintained. Lithium ions do not last long and can last for two to three years (whether or not you use it). Because of this, all lithium-ion battery packs should be replaced every 36 months or so. Moreover, whenever the power drops to 50%, you should be able to charge it. Lithium ions have no memory effect, but too low a voltage can cause serious damage.

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