Preparation and characterization of lithium ion conducting borosiloxane polymer electrolytes

A variety of lithium ion conducting borosiloxane polymers were prepared in high yield. The temperature dependence of ionic conductivity was fit well b y the Vogel-Tammann-Fulcher equation, indicating that ion motion was strong ly coupled to segmental motion of oligoether side chains. The borosiloxane electrolytes also exhibited large fractional free volume at the glass trans ition temperature, which led to enhanced ionic conductivity compared to ele ctrolytes incorporating high molecular weight poly(ethylene oxide). The cat ionic transference number was enhanced due to anion interaction with the Le wis acidic sites on the polymer framework. (C) 2001 Elsevier Science Ltd. A ll rights reserved.