Self-charging biosupercapacitors (BSCs) that can store energy and be self-charged via chemical or solar energy conversion through bioreaction have recently attracted considerable attention. As human sweat also contains a high concentration of lactate biofuel, the harvesting and storage of the bioenergy in sweat holds the potential to provide the power for wearable electronics. A new wearable hybrid device functions as both a biofuel cell and a supercapacitor.