High-Performance Lithium Ion Batteries Combining Submicron Silicon and Thiophene–Terephthalic Acid-Conjugated Polymer Binders

Abstract

We developed high-performance lithium ion batteries (LIBs) based on submicron-sized recycled silicon and conjugated polymer binders. The polymer binders were synthesized by palladium-catalyzed direct arylation of 3-(2-ethylhexhyl)thiophene or 3,3′-di(2-ethylhexyl)bithiophene and dimethyl-2,5-dibromoterephthalate, followed by saponification. The LIBs were fabricated using composites of submicron-sized silicon and the polymer binders without conductive carbon additives. They exhibit a high capacity of up to 2700 mA h g–1 at a high rate of 1.0C, and 52% of this capacity is maintained even after 1000 cycles.