Complex hydride LiBH 4 is a promising solid-state electrolyte (SSE) for rechargeable batteries, owing to its great compatibility with the lithium metal anode and good mechanical properties. However, LiBH 4 only exhibits high ionic conductivity (10 −3 S cm −1 ) with the hexagonal structure at temperatures above 117 °C. To overcome this obstacle, composite poly(ethylene oxide)−hydride electrolytes were synthesized by a solution-casting method. PEO−Li 4 (BH 4 ) 3 I (EO/Li + = 10) delivers the highest ionic conductivity of 4.09 × 10 −4 S cm −1 with high Li + transference number of 0.45 at 70 °C. The addition of nano-SiO 2 as an inorganic filler enhances the dendrite-free ability of electrolyte membranes dramatically and prolongs the cycle life of the Li symmetric battery from <100−360 h. In order to suppress the shuttling effect of polysulfide and volume expansion in lithium−sulfur (Li−S) batteries, sulfurized pyrolyzed poly(acrylonitrile) was selected as the cathode material for all-solid-state batteries, which presented a remarkable cycling stability of 232 (967 for sulfur content) mA h g −1 after 75 cycles. These attempts not only decrease the application temperature of LiBH 4 but also broaden the utilization of hydride in SSEs.

Carbon nanotube/poly(p‐phenylene benzobisoxazole) (CNT/PBO) composite fibres were prepared by in situ polymerization and dry‐jet wet spinning. The structure and properties of the CNT/PBO fibres were investigated. FTIR and viscosity measurements showed that the functional groups on the CNT surface took part in the polymerization and affected the chemical structure and molecular weight of the composite. CNT/PBO composites with high molecular weight could be obtained by controlling the amount and addition time of CNTs. Compared with PBO fibres containing no CNTs prepared under the same conditions, the thermal resistance of the CNT (2 wt%)/PBO fibres was higher and the tensile strength was also improved by 20–50%. WAXD and SEM measurements indicated that the orientation degree of the CNT (2 wt%)/PBO fibres was smaller than that of PBO fibres. The fracture surfaces of these two fibres were also different. CNT dispersion in the CNT (2 wt%)/PBO fibres was examined by TEM. A model of the interactions between CNTs and PBO is proposed, based on these results. Copyright © 2006 Society of Chemical Industry

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