Tiny Robots Powered by Mini Zinc Air Batteries

Researchers in the United States have made a significant advancement in battery technology with the development of a high energy density zinc air battery. This innovative battery has the potential to revolutionize small robotic systems and medical applications, offering a compact and efficient power source.

The miniature battery, created at the Massachusetts Institute of Technology (MIT), is incredibly small, measuring just 0.1mm in length and 0.002mm in thickness. Despite its size, the battery boasts a voltage of 1V and a power output of 2.7nW, making it suitable for powering a variety of small devices such as circuits, sensors, actuators, and memristor circuits. With an energy density exceeding 760Wh/l, this zinc air battery packs a powerful punch in a tiny package.

The design of the battery is both innovative and practical. It consists of a zinc electrode connected to a platinum electrode, both embedded in a strip of SU-8 polymer commonly used in microelectronics. When exposed to oxygen molecules from the air, the zinc electrode undergoes oxidation, releasing electrons that flow to the platinum electrode, thus generating a current. This simple yet effective mechanism allows the battery to efficiently convert chemical energy into electrical power.

One of the key advantages of this new battery technology is its scalability. Using photolithography techniques, researchers can fabricate up to 10,000 batteries from a single wafer, demonstrating the potential for mass production of these miniature power sources. This scalability opens up possibilities for widespread adoption of the technology in various industries and applications.

Michael Strano, the Carbon P. Dubbs Professor of Chemical Engineering at MIT and the senior author of the study, expressed optimism about the implications of this breakthrough. "We think this is going to be very enabling for robotics," said Strano. "We're building robotic functions onto the battery and starting to put these components together into devices." The battery's power output is sufficient to operate sensors that detect changes in electrical resistance when exposed to different chemicals, including sensors made from molybdenum disulfide and carbon nanotubes.