New technology allows robots to eat metal for energy
Researchers have developed an efficient technology for absorbing energy from a metal by cleaving its chemical bonds. This allows devices to receive power continuously without batteries or external forces..
Currently, batteries or energy collectors are used as a separate power source for electronics, generating it under the influence of light, wind, heat and other factors. Batteries store energy internally, which limits the maximum supply and makes them heavy. Collectors such as photocells, although they do not have capacity limits, only function under certain conditions and are not able to quickly convert the surrounding energy.
A team of engineers from the University of Pennsylvania decided to combine the best qualities of these two fundamental technologies by developing an air-metal absorber (AMA). It works on the principle of a battery, as it provides power through repeated destruction and formation of chemical bonds, but at the same time it also acts as a collector, since it extracts energy from the environment..
During operation, such a system actually oxidizes the top layer of the metal and absorbs the electrons released during this process. Power and energy capacity depends on the oxidation potential.
Like a traditional battery, the VMP consists of a cathode connected to a working device, under which there is a piece of hydrogel with a spongy network of polymer chains that conducts electrons between the metal surface and the cathode through water molecules. The hydrogel acts as an electrolyte, and any metal surface it touches functions as the anode of the battery, allowing electrons to flow to the cathode and power the device.
During the study, the team connected a small motorized vehicle to the VMP. Dragging a hydrogel with a small supply of water behind him, he oxidized the metal surfaces on which he drove, leaving behind a microscopic layer of rust. Although the system uses readily available connections, there is a risk that over time, the metal layer can be depleted.
Scientists have tested the effectiveness of the system on aluminum, zinc and stainless steel. Even with the added weight of water, hydrogel, and cathode, the energy density was 13 times that of a lithium-ion battery, and 10 times the power of the best solar panels and wind turbines to date..
Based on this technology, other research teams are already developing low-cost lighting systems for self-contained homes and durable control sensors for shipping containers..
Recall that recently a material was invented that transforms any surface into the solar battery.
text: Ilya Bauer, photo and video: Mack Institute for Innovation Management