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We report a flexible and wearable bacteria-powered battery in which four functional yarns are placed in parallel for biological energy harvesting. A current collecting yarn is sandwiched between two conductive/hydrophilic active yarns including electricity-generating bacteria while a polymer-passivated cathodic yarn is located next to one of the active yarns to form a biological fuel cell configuration. The device uses Shewanella oneidensis MR-1 as a biocatalyst to produce a maximum power of 17μW/cm3 and current density 327μA/cm3, which are enough to power small-power applications. This yarn-structured biobattery can be potentially woven or knitted into an energy storage fabric to provide a higher power for smart textiles. Furthermore, sweat generated from the human body can be a potential fuel to support bacterial viability, providing the long-term operation of the battery.
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Award ID(s):
Publication Date:
Journal Name:
2018 Solid-State Sensors, Actuators and Microsystems Workshop
Page Range or eLocation-ID:
202 to 205
Sponsoring Org:
National Science Foundation
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