According to a research paper published earlier this month, the supercapacitor is made up by a device called a “harvester” that operates by using the body’s heat and movements to extract electrical charges from ions found in human body fluids, such as blood, serum, or urine.

As electrodes, the harvester uses a carbon nanomaterial called graphene, layered with modified human proteins. The electrodes collect energy from the human body, relay it to the harvester, which then stores it for later use.

Because graphene sheets can be drawn in sheets as thin as a few atoms, this allows for the creation of utra-thin supercapacitors that could be used as alternatives to classic batteries.

For example, the bio-friendly supercapacitors researchers created are thinner than a human hair, and are also flexible, moving and twisting with the human body.
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Researchers argue that implantable medical devices using their supercapacitor could last a lifetime, and remove the need for patients to go through operations at regular periods to replace batteries, one of the main causes of complications with implantable medical devices.

Currently, the supercapacitor looks primed to be deployed with pacemakers, but researchers hope their technology could be used with other devices that stimulate other organs, such as the brain, the stomach, or the bladder.

Source: New Battery Technology Draws Energy Directly From Human Body