Implanted pacemakers have saved the lives of millions of patients with cardiac disease. These devices have one major drawback, however; they rely on a rigid battery to provide power and these must be replaced every six to ten years. The replacement procedure is not particularly difficult, but it still requires invasive surgery and represents a significant portion of the health risks in using such as device.

Eliminating the battery would eliminate the need for the replacement procedure, so scientists have been searching for ways to harvest the body’s own energy to power a pacemaker. We’ve covered a variety of approaches over the years, going back to a piezoelectric device in 2014. Now researchers in Beijing, China have come up with a new approach.

They have created a flexible sandwich of materials that works as a triboelectric generator. It produces electricity that can be stored in a capacitor, and then used to power a pacemaker as needed. The material is attached to the outside of the heart, and the muscle contractions cause the layers in the patch to make repeated contact which in turns create the electrical charge. The researchers have tested the device in a living pig and found that it can successfully regulate heart rate and reestablish a normal rhythm after an arrhythmia occurs.

Much more work is needed to make this a practical device. It needs to be smaller and produce a higher energy density in order to make it suitable for minimally invasive implantation. In the long run, this could be a solution for powering a variety of implanted sensors and treatment devices, and not just pacemakers.