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The emergence of the Internet of Things and pervasive sensor networks have generated a surge of research in energy scavenging techniques. We know well that harvesting RF, solar, or kinetic energy enables the creation of battery-free devices that can be used where frequent battery changes or dedicated power lines are impractical. One unusual yet ubiquitous source of power is soil (earth itself) - or more accurately, bacterial communities in soil. Microbial fuel cells (MFCs) are electrochemical cells that harness the activities of microbes that naturally occur in soil, wetlands, and wastewater. MFCs have been a topic of research in environmental engineering and microbiology for decades, but are a relatively new topic in electronics design and research. Most low-power electronics have traditionally opted for batteries, RF energy, or solar cells. This is changing, however, as the limitations and costs of these energy sources hamper our ability to deploy useful systems that last for decades in challenging environments. If large-scale, long-term applications like underground infrastructure monitoring, smart farming, and sensing for conservation are to be possible, we must rethink the energy source.
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From Microbial Fuel Cells to Biobatteries: Moving toward On‐Demand Micropower Generation for Small‐Scale Single‐Use Applications
Abstract Microbial fuel cells (MFCs) that generate electricity generation from a broad diversity of biomass and organic substrates through microbial metabolism have attracted considerable research interest as an alternative clean energy technology and energy‐efficient wastewater treatment method. Despite encouraging successes and auspicious pilot‐scale experiments of the MFCs, increasing doubts about their viability for practical large‐scale applications are being raised. Low performance, expensive core parts and materials, energy‐intensive operation, and scaling bottlenecks question a sustainable development. Instead, special MFCs for low‐power battery‐reliant devices might be more applicable and potentially realizable. Such bacteria‐powered biobatteries would enable i) a truly stand‐alone device platform suitable for use in resource‐limited and remote regions, ii) simple, on‐demand power generation within a programmed period of time, and iii) a tracelessly biodegradable battery due to the use of the bacteria used for power generation. The biobattery would be an excellent power solution for small‐scale, on‐demand, single‐use, and disposable electronics. Recent progress of small‐scale MFC‐based biobatteries is critically reviewed with specific attention toward various device platforms. Furthermore, comments and outlook related to the potential directions and challenges of the biobatteries are discussed to offer inspiration to the community and induce fruitful future research.
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- Award ID(s):
- 1703394
- PAR ID:
- 10457121
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Materials Technologies
- Volume:
- 4
- Issue:
- 7
- ISSN:
- 2365-709X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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