UCLA announced that scientists from UCLA and University of Connecticut designed a new form of energy storage for powering implantable medical devices that do not require a battery.  According to the announcement, this design makes it possible for implantable medical devices to be powered by a patient’s own body.

The announcement notes that many powered implantable medical devices, such as pacemakers, contain traditional batteries, which limit the lifespan of a device to the lifespan of the battery.  According to the Mayo Clinic, the battery of a pacemaker typically lasts five to 15 years, and needs to be replaced by surgery when it runs out. According an editorial in the BMJ (formerly the British Medical Journal), “[o]ver half of all patients with pacemakers require a replacement procedure because the batteries have reached their expected life. Some 11-16% need multiple replacements.”  Moreover, the article notes that batteries make the implantable device bulky and contain toxic chemicals, which can be harmful to the patient if they leak.

According to UCLA, the new energy storage system is called a biological supercapacitator, which operates on electrolytes in the patient’s body, for example, in blood and urine, and eliminates the need for a traditional battery in an implantable medical device.  The researchers state that the biological supercapacitator can be combined with “an energy harvester” to also convert heat and motion of the patient into electricity to be captured by the supercapacitator.

Although the announcement states that supercapacitators are currently not widely used in implantable device technology, Maher El-Kady, a UCLA postdoctoral researcher and a co-author of the study, commented:

In order to be effective, battery-free pacemakers must have supercapacitors that can capture, store and transport energy, and commercial supercapacitors are too slow to make it work.  Our research focused on custom-designing our supercapacitor to capture energy effectively, and finding a way to make it compatible with the human body.

More details of the research team’s design can be found in a paper recently published in Advanced Energy Material.