Microbial Fuel Cell Fabbed on Flex Fabric

　　There are already light-emitting fabrics, thermoelectric energy-harvesting fabrics, and zinc-silver-oxide rechargeable battery fabrics. Now add microbial-fuel-cell fabrics to the list of lab-demonstrated technologies for wearable devices.

　　In an Advanced Energy Materials paper, Binghamton University (State University of New York) researchers Sumiao Pang, Yang Gao, and Seokheun Choi describe the construction of a fuel-cell fabric based on the monolithic integration of bacteria into a single-layer, flexible, stretchable substrate. The microbial fuel cell (MFC)uses the pseudomonas aeruginosa bacteria as an enzyme catalyst to boost the membrane-free fuel cell’s output to 6.4 microwatts per square centimeter. With a current density of 52 microamps/square centimeter, the material reportedly provides higher output than other experimental fabrics and rivals the output of paper-substrate microbial fuel cells on which Choi previously reported.

　　The experimental design’s membrane-free, single-chamber architecture simplifies the material’s fabrication and improves the performance of the microbial fuel cell, according to the authors. To test the stability of the material, the researchers put it through repeated stretching and twisting operations and say they observed no degradation in its performance.

　　The conductive and hydrophilic anode is embedded into a three-dimensional microchamber in the fabric to maximize its bacterial electricity-generating performance by virtue of the liquid environment. The solid-state silver oxide/silver material used for the cathode produces a fast catalytic reaction, according to the authors.

　　The researchers used a printing process to form 35 individual microchambers simultaneously, suggesting that the method will scale easily for mass production of textile microbial fuel cells. The result is a stretchable and twistable power source that can power wearable electronics. Further, according to the researchers, the assembly can be configured to harvest the perspiration of its wearer, potentially providing continuous long-term operation while being worn. It could also serve as a disposable power source in products such as single-use medical diagnostic patches.

　　The National Science Foundation, the Binghamton University Research Foundation, and a Binghamton University Analytical and Diagnostics Laboratory Small Grant funded the project. Read “Flexible and Stretchable Biobatteries: Monolithic Integration of Membrane-Free Microbial Fuel Cells in a Single Textile Layer” for details on the work.