Search

Aqueous zinc ion batteries have attracted much attention due to their abundant resources, high safety and low cost. However, the problems of uncontrolled dendrites growth, corrosion, and hydrogen evolution of zinc anodes seriously restrict the cycling life of batteries, limiting the large-scale applications. Herein, a simple drop-coating method is applied to prepare polyimide (PI) glue functionalized glass fiber separators (PI-GF). The carbonyl group in imide (–CO–N–CO–) group of polyimide has a strong adsorption effect on Zn, which helps accelerate the conduction of Zn2+, reduce the nucleation overpotential, and realize fast reaction kinetics. The composite separators reduce the concentration polarization, promote the uniform deposition of Zn2+ to inhibit the growth of dendrites, and thus significantly improving the stability of zinc anodes. Most anticipatedly, the Zn//Zn symmetric battery using the PI-GF separator exhibits a highly reversible plating/stripping behavior and can be stably cycled for 1280 h at 1 mA cm−2 and 1 mAh cm−2. The Zn//V 2 O 5 full battery also delivers an excellent cycling stability with a high capacity of up to 235.5 mAh g−1 after 1000 cycles at a current density of 1 A g−1. This work provides a simple and effective method to improve the electrochemical performance of zinc anodes. • Polyimide glue functionalized glass fiber composite separator has been prepared. • Polyimide composite separator for highly stable zinc anodes. • The separator exhibits excellent mechanical strength and electrolyte wettability. • The carbonyl group in imide group has a strong adsorption effect on zinc ions. • The separators could reduce concentration polarization and homogenize Zn2+ flux. [ABSTRACT FROM AUTHOR]

Abstract: Nitrogen-doped carbon coated Li4Ti5O12 (NC–LTO) nanocomposite as an anode material for lithium-ion batteries (LIBs) is prepared with acetyl glucosamine as carbon source by pre-coating process combined with ball milling. X-ray diffraction, field emission scanning electron microscopy, transmission electron microscopy and X-ray photoelectron spectroscopy are used to characterize the NC–LTO materials. The results show that NC–LTO samples exhibit the obvious improvements in rate capability and cycling performance compared with the LTO samples coated by carbon (C–LTO) derived from sugar and pure LTO samples. The carbon pre-coating process could significantly decrease the agglomeration of TiO2 precursors and the uniformly coated nitrogen-doped carbon increase the interfacial stability and electric conductivity of LTO. At the charge–discharge rate of 0.2 C, 5.0 C and 10.0 C and 20.0 C, the discharge capacities of NC–LTO samples are 167.4, 146.3, 133.4 and 128.2 mAh g−1, respectively. After 1000 cycles at 1 C, its capacity retention is 95.9% with nearly ignored capacity fading. [Copyright &y& Elsevier]