Hybrid organic-inorganic nano-composites for solid-state battery electrolytes
November 10-14, 2019
Desired properties of solid electrolytes are high ionic conductivity and transference number, high shear modulus to prevent dendrite growth, chemical compatibility with electrodes, and ease of fabrication into thin films. Especially, elastic stiffness and ionic mobility are opposing attributes in a homogenous material, and a composite approach towards designing novel electrolytes is therefore advisable. We use a two-step sol-gel method to synthesize silica-based hybrid organic-inorganic materials for this application. First, a continuous porous silica structure is created that provides electrochemical stability and mechanical rigidity. This network also contains unreacted epoxy groups. In step 2, single-sided amine-functionalized polyethene glycol (PEG-NH2) infiltrates the pores via fluid exchange. As PEG-NH2 fills the pores, the amine groups react with the epoxy groups and anchor the polymer to the silica network, which provides highly conductive pathways. IR spectroscopy, Raman and Brillouin light scattering, impedance spectroscopy, small angel x-ray scattering (SAXS), charge-discharge cell testing is performed to identify the structural and chemical origins that underlie the performance of these hybrid electrolytes. A room temperature ionic conductivity in excess of 10-5 S/cm is reached (Fig. 1).
Please click Additional Files below to see the full abstract.
John Kieffer, Vazrik Keshishian, Cameran Beg, and Weimin Wang, "Hybrid organic-inorganic nano-composites for solid-state battery electrolytes" in "Composites at Lake Louise 2019", John Kieffer, University of Michigan, USA Erik Spoeke, Sandia National Laboratories, USA Meisha Shofner, Georgia Institution of Technology, USA Eds, ECI Symposium Series, (2019). https://dc.engconfintl.org/composites_all_2019/62