The use of boroxine rings for the development of high performance polymer electrolytes

Boroxine ring containing additives, Bx(n)= B3O3[O(CH2CH2O)(n)CH3](3), were found to be compatible with a wide variety of polymer hosts. Polymer electrolytes exhibiting room temperature conductivities of up to 10(-5) S cm(-1) were obtained by incorporation of Bx(n) and LiCF3SO3 into poly((methyl methacrylate) and propylene oxide-ethylene oxide co-polymers. Polymers composed of inter-connecting networks of boroxine rings were also investigated as suitable hosts for the boroxine additives B3O3[O(CH2CH2C)nCH(3)](3). Poly(methyl methacrylate) systems exhibited an electrochemical stability window in the region of 4.9 V, while transference number measurements indicated high Li+ ion conductivity. (C) 2000 Elsevier Science Ltd. All rights reserved.