The effects of carbonization conditions on electrochemical performance of attapulgite-based anode material for lithium-ion batteries

Abstract

In this work, attapulgite-based anode materials with different polyacrylonitrile contents were fabricated. The effect of polyacrylonitrile contents on electrochemical performances of the anode materials was systematically investigated. The optimal attapulgite/polyacrylonitrile ratio for the anode material was selected via comparing with electrochemical specific capacity at the same current density. It was shown that the specific capacity of the sample with 20 wt% polyacrylonitrile could reach a maximum value of 446.5 mAh g⁻¹ at the same current density. Furthermore, the effect of carbonization temperatures on electrochemical properties of the anode materials with 20 wt% polyacrylonitrile was investigated. The structural features of the carbonized samples were characterized by Fourier transform infrared spectroscopy, X-ray diffraction, Brunauer–Emmett–Teller, field emission scanning electron microscopy, transmission electron microscopy, energy dispersive spectrometer and X-ray photoelectron spectroscopy. The discharge specific capacity of the anode material carbonized at 800 °C reached the maximum value of 446.5 mAh g⁻¹ at a current density of 0.1 A g⁻¹ at the 50th cycle. The coulombic efficiency of the AT-based anode material carbonized at 800 °C was 99.8% at the current density of 0.5 A g⁻¹ at the 300th cycle. The anode material carbonized at 800 °C with a mass loading of 0.85 mg cm⁻² had excellent electrochemical conductivity and rate capability.