Automotive

'Metal-Air Scavenger' to Power Electronics, Robots, and Vehicles

Researchers from Penn Engineering  introduce their "metal-air scavenger" vehicle, which gets energy not from a battery, but from breaking chemical bonds in the aluminum surface it travels over. The technology works like both a battery and an energy harvester; the result is a power source that has ten times more power density than the best energy harvesters and 13 times more energy density than lithium-ion batteries. Like a traditional battery, the metal-air scavenger starts with a cathode that’s wired to the device it’s powering. Underneath the cathode is a slab of hydrogel, a spongy network of polymer chains that conducts electrons between the metal surface and the cathode via the water molecules it carries. With the hydrogel acting as an electrolyte, any metal surface it touches functions as the anode of a battery, allowing electrons to flow to the cathode and power the connected device. For this study, the Penn Engineering researchers connected a small motorized vehicle to the device. They say that in the future, robots could keep themselves powered by seeking out and “eating” metal, breaking down its chemical bonds for energy like people do with food.