Researchers in Illinois have come up with stretchable batteries that can expand to three times their normal size.
The end goal with the stretchable batteries is to create wearable sensors to help with athletic performance and health monitoring. These stretchable batteries could even be stretched thin enough to be applied inside the body, such as on the surface of the heart. Such applications require a power source, and until now, power sources are generally bulky and rock solid. The way that John Rogers and the researchers at MC10 got around that issue was to essentially create a stretchable silicone sheet that has a large array of several smaller lithium ion batteries connected by smaller but extendable cables. The result is a stretchable battery that can expand 300 percent larger than its normal size.