A smartphone with a battery made of self-healing material? Sounds too good to be true? This might become reality one day, according to new findings presented at the 253rd National Meeting & Exposition of the American Chemical Society (ACS).
We might soon have self-healing smartphones! We won’t have to worry about not having a Nokia-3310-strong phone!
A team of researchers from the University of California, Riverside, claim to have developed a self-healing polymeric material that is both flexible and transparent. Imagine having a smartphone with self-healing parts made of this substance!
The inspiration behind the creation thereof is Wolverine from the X-Men. Study author, Chao Wang, explains that he has been a great fan of the comic-book character, Wolverine, who can heal himself when injured, and thus able to save the world. Just like Wolverine’s skin can restore itself, the said material is described as being able to become whole again after breaking into two pieces. From this came the concept of a smartphone with a self-healing battery.
Wang has been investigating the possibility of having a self-repairing lithium ion battery that would last longer through the ‘ability’ of fixing itself if the phone falls down. Wang, together with his colleagues, have ultimately worked on such a material that can conduct ions to generate current.
How can the material self-repair? According to Wang, it is all about its chemical bonding. Existing materials have either of two types of bonding: the strong covalent bonds which are harder to manipulate, or the weaker and more dynamic non-covalent ones. Current polymers that are self-healing use a form of non-covalent bonds, which are easily broken to reform again; this is the same type of force connecting water molecules, thus allowing it to exist as a fluid. However, these bonds are not suitable for ionic conductors, explains Wang.
Wang and his colleagues, therefore, looked into a different type of non-covalent bond known as ion-dipole interaction, which is found between charged ions and polar molecules. According to Wang, their use of this bond to make self-healing polymers is unprecedented. They have also found that the ion-dipole interactions are specially appropriate for ionic conductors. They used this bond to create the material by connecting a polar, flexible polymer, poly(vinylidene fluoride-co-hexafluoropropylene), with a mobile, ionic salt; the polymer is kept together through ion-dipole interactions that occur between the ionic salt and the polar groups of the polymer.
The findings show that the resulting material stretches up to 50 times its actual size. When broken into two, it could get back together in one single piece—a self-healing process that happened within a day.
Now, the aim is to improve its properties to make a better polymer. One of these steps is to test the material in high humidity conditions.
“Previous self-healing polymers haven’t worked well in high humidity,” Wang says. “Water gets in there and messes things up. It can change the mechanical properties. We are currently tweaking the covalent bonds within the polymer itself to get these materials ready for real-world applications.”