Self-healing items seem to be all the rage right now. From electronic circuits to concrete to airplanes, self-healing technology gives us objects that can take a beating and last longer. Now, scientists have developed a self-healing battery electrode that could mean longer battery life for electric cars, cellphones, and other devices.
Cellphones are notorious for poor battery life, made worse by the limited number of cycles (discharge and charge) that their lithium ion batteries can undergo. In the quest for smaller batteries with better battery life (which is generally sacrificed with smaller cell phones), a solution is needed. One possible answer is using silicon electrodes. These high capacity electrodes are small and made of nanoparticles. They’re also inexpensive to make, but they come with an inherent problem: they swell and shrink during battery usage and eventually, this causes the material to crack and disintegrate, damaging the battery.
To solve this problem, scientists at Stanford University and the Department of Energy’s SLAC National Accelerator Laboratory looked to biology for inspiration. Self-healing is something that animals and plants do naturally, so they decided to create something that would allow the silicon electrodes to do the same. They created a self-healing polymer with carbon nanoparticles by making the chemical bonds of the polymer weaker. Because of this, the material breaks easily, but its parts reattach due to the way the chemicals are attracted to each other, similar to how human DNA operates. The scientists then used this polymer to coat the silicon electrodes, which lasted 10 times longer with its new self-healing material.
At present, we’re still not ready to use silicon electrodes in our batteries, but this group of scientists are working on that. The goal is to work up to about 500 cycles for cell phone batteries and 3000 for electric vehicles. Right now, they’re only at about 100. However, the technology is definitely there, and the research team believes that it’s doable.