As the news of overheating lithium-ion batteries continues to surface, the industry is working to develop fuel and energy cells made of different materials. And a group of US and UK researchers has made a breakthrough in the development of batteries that use bacteria as their reactive material.
Researchers at Pacific Northwest National Laboratory in Washington state and the UK's University of East Anglia have found that it's possible to produce an electrical current by touching proteins on the surface of bacteria to a mineral surface, thus paving the way for the creation of microbial fuel cells.
The scientists said in a press release that they created a synthetic version of the marine bacteria shewanella oneidensis using proteins that are thought to move electrons.
They inserted these proteins into the lipid layers of vesicles, which are small capsules of lipid membranes such as the ones that make up a bacterial membrane. Then they tested how well electrons travelled between an electron donor on the inside and an iron-bearing mineral on the outside.
Researchers have found that they can create an electrical current when proteins on the surface of bacteria
(like shewanella oneidensis, shown here) touch a mineral surface. The research
shows that it is possible to develop microbial fuel cells.
(Source: University of East Anglia/Alice Dohnalkova)
Tom Clark, the lead researcher on the project from UEA’s School of Biological Sciences, said in the release:
We knew that bacteria can transfer electricity into metals and minerals, and that the interaction depends on special proteins on the surface of the bacteria. But it was not been clear whether these proteins do this directly or indirectly though an unknown mediator in the environment.
The researchers found that it's possible to place bacteria directly on the surface of a metal or mineral and transfer electricity through their cell membranes, therefore tethering bacteria directly to electrodes.
"This is the first time that we have been able to actually look at how the components of a bacterial cell membrane are able to interact with different substances, and understand how differences in metal and mineral interactions can occur on the surface of a cell," Clark said.
Though there is still a ways to go before batteries can be developed using this method, "these bacteria show great potential as microbial fuel cells, where electricity can be generated from the breakdown of domestic or agricultural waste products," he said.