MFC Efficiency

Overview

Figure 1: Schematic illustration of the general microbial fuel cell functional principle, showing the flow of charged species during operation.

To determine how well the different BioBricks we create really work in the designated environment, the design and construction of a suitable microbial fuel cell was necessary. This fuel cell has to meet several requirements. As explained previously it should consist of two chambers, separated by a material that is only traversable for cations. Both chambers have to contain an electrode, which has to be electrically conductive. Also, they should have a large surface area, in order to allow contact to a high number of electron donors at the same time. Both the anode and the cathode chamber also have to be air-tight, since the reaction has to take place under anaerobic conditions. For obvious reasons, we aim at keeping the costs for the cell low by using materials which cost as little as possible while still performing well.
Construction of a first prototype began in May. After initial testing, the design underwent significant changes over the course of the project. Important stages of this process are shown below, along with a description of their design and the flaws that led to the planning of a new model.

References

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• Sell, D., Krämer, P., & Kreysa, G. (1989). Use of an oxygen gas diffusion cathode and a three-dimensional packed bed anode in a bioelectrochemical fuel cell. [http://link.springer.com/article/10.1007/BF00262465 Applied microbiology and biotechnology, 31](2), 211-213.