ORMOCERS AS INORGANIC-ORGANIC ELECTROLYTES FOR NEW SOLID-STATE LITHIUM BATTERIES AND SUPERCAPACITORS

ORMOCERs (ORganically MOdified CERamics) are inorganic-organic copolym ers which are synthesized as matrix for Li-ion conduction. The inorgan ic oxidic backbone of these materials results from polycondensation of alkoxy compounds whereas the organic network is formed from reactive functional groups R' of alkoxysilanes of the type R'Si(OR)(3), or by c o-polymerising reactive organic monomers with reactive functionalized alkoxysilanes. Depending on the reactive organic functionalities and t heir thermal and uv-initiated organic crosslinking reactions the mater ials were adapted to the needs of battery and supercapacitor manufactu ring. For ionic conductivity polyethers with different chainlengths an d functionalized (eg epoxy) termination sites were synthesized and att ached to organically functionalized oxidic oligomers. Conductivities o f up to 10(-4) Omega(-1) cm(-1) at room temperature (RT) were achieved without plasticizer. The electrolytes form an amorphous network with configuration temperatures T-o. (according to Vogel-Tammann-Fulcher) c lose to -80 degrees C, several degrees below the transformation temper ature T, (measured by DSC) in agreement with conventional configuratio n theory. The activation energies correlate favourably with results fo r good polymer electrolytes. (C) 1998 Elsevier Science Ltd. All rights reserved.