Ayan Ghosh, Department of Chemical and Biomolecular Engineering, University of Maryland, 2113 Chemical and Nuclear Engineering Bldg, College Park, MD 20742 and Peter Kofinas, Fischell Department of Bioengineering, University of Maryland, 1120 Jeong H Kim Engineering Bldg 225, College Park, MD 20742.
As technology evolves, leading to a constant miniaturization of electrical devices, the need for a compact, lighter, safer and versatile energy source has been a critical limiting factor. Owing to its highly reactive nature, lithium batteries currently in use require thick and bulky containment layers in order to protect its components. Polymer electrolytes offer an attractive alternative by eliminating the safety risks posed by the corrosive organic electrolytes currently in use and also by being light-weight and flexible. Poly(ethylene oxide) (PEO) a popular solvent-free electrolyte, has been known for its ability to complex with lithium based salts. It however, suffers from low conductivity performance at room temperature owning to its semi-crystalline nature. We have developed a solid state nanostructured electrolyte based on a self-assembled block copolymer, which exhibits enhanced lithium transport. The electrolyte forms flexible translucent films which exhibit an average ionic conductivity value of 1.26 × 10-5 Scm-1 at room temperature (21 °C). Conductivity data was obtained from impedance response, while differential scanning calorimetry (DSC) and transmission electron microscopy (TEM) were performed to characterize the intrinsic properties of the material.