Improving Battery Systems for Miniature Satellites: CubeSats
Ryan Karkkainen, assistant professor in the Department of Mechanical and Aerospace Engineering, is leading the research of a new solid-state battery prototype, collaborating with Luke Roberson of NASA’s Kennedy Space Center (KSC) in Florida, Glenn Research Center (GRC) in Ohio, and with Xiangyang Zhou, associate professor in the Department of Mechanical and Aerospace Engineering.
The research project, titled “Development of Lightweight CubeSat With Multifunctional Structural Battery Systems,” consists of reducing the volume of batteries used to power miniature satellites, including CubeSats, cutting back the total weight of the satellite and allowing more space for research purposes.
A CubeSat is a type of miniaturized satellite for space research that is usually no larger than a toaster. It was first proposed in 1999 by professors at California Polytechnic State University and Stanford University to enable graduate students to design, build, test and operate experiments in a spacecraft with capabilities comparable to those of the first spacecraft, Sputnik. Over time, the CubeSat became a standard for miniature satellites.
Due to their small size, space is crucial in CubeSats. The new battery would minimize or eliminate the need for conventional batteries currently used to power miniature satellites, thus allowing more space for the compact science payload.
“Structural integration with mediator-enabled polymers and electrodes are key to breaking through the technological limitations that would otherwise prohibit these structural battery concepts,” explains Karkkainen.
“Mediators” are redox molecules with a fast exchange rate. When incorporated into polymers and fibers, the mediators enable fast electron transfer and ionic conductivity in a wide temperature range. The battery system would function similar to a standard electric battery, with strong carbon fibers incorporated into the terminals.
“Ultimately,” says Karkkainen, “we will have a multifunctional hybrid battery-capacitator system that serves as both a lightweight load-bearing structure and an electrochemical battery system, thus extending payload and range capabilities while reducing total mass.”
The research team, composed of two faculty members and two graduate students, two undergraduate students and multiple collaborators from NASA KSC and GRC, will use facilities both here at the University of Miami and at NASA to maximize the load capacity and electrical performance of each material and of the battery system.
The development of the structural battery can not only be transferred to other spatial applications (satellite structural trusses, the International Space Station), it can essentially be used to power habitat structures established on another planet.