why some lithium-ion batteries explode - 18650 rechargeable lithium ion battery
Real-
Time images capture a chain reaction that causes lithium
Ion battery to explode.
This process can be done in a few milliseconds: the overheated battery module produces a domino effect, generating more and more heat, and the battery explodes.
But according to a new study published today, not all batteries are equally likely to fail (April 28)
In the journal Nature Communications
"The presence of certain safety features can mitigate the spread of this heat runaway process," the research firm said.
Author Paul Shearing is a chemical engineer at University College London, UK.
These features include mechanical brackets inside the battery, says Shearing.
The results present some methods for making rechargeable lithium.
The researchers wrote in the paper that ion batteries are safer. [
9 strange ways your tech device can hurt you]
Rechargeable battery-
Ion batteries are the main force in modern times. day gadgets;
Everything from smartphones to jumbo jets to Tesla Model S has them.
They are usually made of two layers of material known as the anode and cathode, separated by a conductive fluid.
Lithium ion starts with the cathode, which is a layer of material, usually including cobalt, manganese, nickel and oxygen, in notebook computers and mobile phone batteries.
When the battery is charged, electricity drives lithium ion from the cathode through ions
A filled electrolyte liquid and enters an anode stacked from graphite.
When the battery runs out, the lithium ion returns from the anode to the cathode.
The battery is usually a battery;
The laptop battery could have three or four batteries, while the Tesla Model S could have thousands of batteries, Shearing said.
Chain Reaction of hundreds of millions of lithium
Annual production of ion batteries, catastrophic failures such as explosion or melting are rare, says Shearing.
Nevertheless, there have been 43 product recalls of defective lithium
According to U. S. data, Ion batteries since 2002S.
Consumer Product Safety Committee
The battery may explode or melt when internal electrical components are short-circuited
When mechanical problems come out after a fall or accident, or when they are not installed correctly, the circuit will appear, Shearing said.
But essentially, all of these failures are due to the fact that a part of the battery is too hot to cool fast enough to produce a chain reaction that generates more and more heat.
"It's a snowball process, and we call it heat out of control," Shearing told Live Science . ".
Shearing said that during the heat out of control, the micro-battery module will melt, release heat, and the electrolyte material between the anode and the cathode may even boil.
To learn more about this dangerous chain reaction, cutting and his colleagues heated commercial lithium
Ion batteries of 482 degrees Fahrenheit (
250 degrees Celsius). Using a high-
Speed 3D camera and particle collider, X-with synchronous accelerator-
Light, when the battery went through a flash transition of overheating and heat out of control, the team took a thermal image of the battery.
The battery is safer even at high temperatures, not all batteries fail
Some internal safety features that prevent dangerous reactions.
In those batteries that do fail, the battery with an internal bracket remains intact until the internal temperature reaches 1,830 F (1,000 C).
At this time, the internal copper material melted, causing the chain reaction to get out of control.
But the battery that didn't have these internal brackets exploded, probably because their internal core crashed
The study shows that the internal electrical components are connected by a circuit.
Shearing said the new technology provides a way to systematically test the safety features of the battery in the future.
Shearing said that although the batteries that exploded sounded terrible, they were actually very rare.
After all, most people don't bake iPhones in their daily use, he said.
"We have to push these situations to the extreme,you]
It's unlikely to see it on your normal day-to-
"Business during the day," cut said . ".
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Originally published on Live Science.
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