At the Swiss University of Friborg, researchers have managed to reproduce the process of generating an electric current as it occurs in the body of a living being - an electric eel. And even the indicators turned out to be similar, but it is much more important that the technology is extremely simple and cheap to reproduce. In the future, it will become the basis for generators integrated into the human body.
An electric eel generates a current on command from the brain, which sends a neural impulse to the membrane system. It separates the electrocyte cells, which are very, very many in the body of the eel. Some of them are always positively charged, the second negatively, so when the membrane opens, there is a movement of ions with a voltage of up to 150 millivolts per cell. That in total can give up to 600 V, depending on the size of the individual.
Positive and negative charges in electrocytes are created due to chemical reactions, which is easy to repeat in a hydrogel. Using 3D printing, two sheets of slightly larger than A4 size were created, on which 2500 drops of different types of hydrogel were adjacent to each other. When the sheets were aligned, a contact occurred, which triggered the flow of ions and gave an electric current with a voltage of 110 V.
Further optimization of the technology led to folding the sheets according to the origami principle, which allows the entire field with gel drops to be compressed to the size of one point in space. And thus significantly increase the efficiency of energy production - the geometry of living eel cells has a similar appearance. Now scientists are working to learn how to print thinner designs with hydrogel. This will allow more cells to be placed on the same area and increase the efficiency of power generation.
With the proper level of miniaturization, such a system can be mounted directly on the skin or in the internal organs of a person without risk to health. And this is already a passive source of energy for future implants.