Self-Assembled Stable Radicals for Improved Battery Performance

• Applicant: Dr. Clemens Liedel
• Subject Area: Preparatory and Physical Chemistry of Polymers ; Polymer Materials
• Term: from 2014 to 2015
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 253291029

There is a magnitude of reasons to research on new energy storage materials in Germany like, amongst others, the German nuclear phase-out, the development of consumer electronics and the high environmental awareness. As renewable energy develops rapidly in Germany, and as solar or wind power is not continuously available, new devices for energy storage are necessary. Consumer electronics like modern smartphones might profit from batteries that can be charged completely within few minutes, and especially new batteries that are free of heavy metals like lead and cadmium would hereby address the increasing environmental awareness of modern people. As a side effect, the production of such batteries would reduce the need of a country to import such metals. Thin, paper-like batteries could additionally afford completely new applications.All of these needs are addressed in the planed research project on stable radical polymer based, metal free batteries with a high charging and discharging speed. Within the last years, first similar devices were produced especially in Japan, but most prototypes depended on the large scale addition of filling and binding materials and metal counter electrodes.In order to address the drawbacks that counteract large scale production of such prototypes, a new approach shall be investigated in this project, leading to a larger energy storage capacity, conductivity and stability of the electrode materials in such stable radical polymer based batteries. Self-assembled block copolymers will be investigated. Because of the closer packing of radical sites, the amount of added filler material will be drastically lower, leading to higher charge density and conductivity of the electrodes. Using materials with liquid crystalline constituents, the solubility of the electrodes in electrolyte solutions in batteries will be drastically lowered, also leading to a reduced need of binders in the material. To further increase the conductivity of the new electrodes, composite materials of block copolymers and nanoparticles will be investigated. Already gained expertise on similar composite materials will be utilized hereby. The finally produced electrodes made from stable radical block copolymers and nanoparticles will have the capability of faster energy release and charging speed and a higher energy storage density compared to similar prototypes produced hitherto - and a much higher potential than conventional batteries.

• DFG Programme: Research Fellowships
• International Connection: USA
• Host: Professor Christopher K. Ober, Ph.D.