Implantable devices in the human body (i.e. pacemakers) have saved countless lives. However, there are many risks that come with having implantable devices in the human body. For example, pacemakers need batteries to operate, and batteries need replacement every so often. This means more surgeries, let alone the possibility that a battery could leak, releasing toxic materials into a patient.
Enter research from UCLA and the University of Connecticut. They have designed a new bio-friendly energy storage system called a biological super capacitor, which operates using charged particles, or ions, from fluids in the human body. The device is harmless to the body's biological systems, and it could lead to longer-lasting cardiac pacemakers and other implantable medical devices.
The researchers propose storing energy in those devices without a battery. The super capacitor they invented charges using electrolytes from biological fluids like blood serum and urine, and it would work with another device called an energy harvester, which converts heat and motion from the human body into electricity. That electricity is then captured by the super capacitor.
Modern pacemakers are typically about 6-8 millimeters thick, and about the same diameter as a 50-cent coin; about half of that space is usually occupied by the battery. The new super capacitor is only 1 micrometer thick, meaning that it could improve implantable devices' energy efficiency. It also can maintain its performance for a long time, bend and twist inside the body without any mechanical damage, and store more charge than the energy lithium film batteries of comparable size that are currently used in pacemakers.