Airplane fires, as well as those caused by electric vehicles, are notoriously difficult to control.
Many airplane fires are caused as a result of Lithium-ion batteries which, according to Science Magazine; ‘If crushed and twisted, the porous plastic membrane that separates the electrodes inside can instantly shred and cause a short circuit, igniting the battery’s highly flammable lithium electrolyte.’
These batteries were placed under a great deal of scrutiny recently, due to their use in mobile phones. The issue stemmed from a spate of cases in which the phones began exploding on planes. There have also been recent reports of discarded batteries causing trash fires. Not good.
Considering the batteries are so commonplace, it’s been surprising how long it has taken to develop some kind of solution (no pun intended). That is, however, what has finally happened, with the announcement of the peculiar sounding oobleck, which takes its name from a Dr Seuss book.
Basically, a form of homemade slime popular with children, oobleck is a liquid mixture of cornstarch and water. Gabriel Veith, a chemist, along with his colleagues at Oak Ridge National Laboratory in Tennessee have been developing an advanced form of the substance ever since Veith made a discovery while concocting a batch of oobleck for his kids.
According to Science:
“While mixing up some oobleck for his children, Veith got an idea worthy of a cat in a hat with a vat: Replace the cornstarch with silica and mix it into the electrolyte of a lithium-ion battery to produce a variation that transforms from flammable fluid to inert solid when impacted. In chemical terms, it’s called a shear thickening fluid.
The trick was finding the right kind of silica. Other labs had tried irregularly shaped and rod-shaped silica particles, but, as they described earlier this year in Applied Materials & Interfaces, Veith’s team turned to a decades-old technique called the Stöber process to produce perfectly round nanoparticles of silica—often used to deliver medicine inside human cells. Such round particles are able to organize themselves into stronger barriers—and they’re easier to produce, Veith says. “You don’t have to reinvent the battery processing line because it’s compatible with present manufacturing technology.””
The resulting oobleck, which has the slightly less amazing title of Safe Impact Resistant Electrolyte, manages to quell the ignition which has, up until now, taken place when Lithium-ion batteries are damaged.
Randall Hyman of Science concludes that: “Veith’s team is working on a version that turns into a brick and stays that way. He notes it could be used in military jackets that transform from wearable batteries to life-saving armor when struck by bullets. After regulatory review, the Oak Ridge team expects its technology will be implemented in batteries within a few years, starting with the least “risk averse” applications. Thing One and Thing Two would be proud.”