Electrochemical study on nickel aluminum layered double hydroxides as high-performance electrode material for lithium-ion batteries based on sodium alginate binder

Nickel aluminum layered double hydroxide (NiAl LDH) with nitrate in its interlayer is investigated as a negative electrode material for lithium-ion batteries (LIBs). The effect of the potential range (i.e., 0.01-3.0 V and 0.4-3.0 V vs. Li+/Li) and of the binder on the performance of the material is investigated in 1 M LiPF6 in EC/DMC vs. Li. The NiAl LDH electrode based on sodium alginate (SA) binder shows a high initial discharge specific capacity of 2586 mAh g(-1) at 0.05 A g(-1) and good stability in the potential range of 0.01-3.0 V vs. Li+/Li, which is better than what obtained with a polyvinylidene difluoride (PVDF)-based electrode. The NiAl LDH electrode with SA binder shows, after 400 cycles at 0.5 A g(-1), a cycling retention of 42.2% with a capacity of 697 mAh g(-1) and at a high current density of 1.0 A g(-1) shows a retention of 27.6% with a capacity of 388 mAh g(-1) over 1400 cycles. In the same conditions, the PVDF-based electrode retains only 15.6% with a capacity of 182 mAh g(-1) and 8.5% with a capacity of 121 mAh g(-1), respectively. Ex situ X-ray photoelectron spectroscopy (XPS) and ex situ X-ray absorption spectroscopy (XAS) reveal a conversion reaction mechanism during Li+ insertion into the NiAl LDH material. X-ray diffraction (XRD) and XPS have been combined with the electrochemical study to understand the effect of different cutoff potentials on the Li-ion storage mechanism.

Automated summary

NiAl LDH electrode with SA binder exhibits high initial discharge specific capacity and good stability in the potential range of 0.01-3.0 V vs. Li+/Li, outperforming PVDF-based electrodes. Ex situ XPS and XAS studies reveal a conversion reaction mechanism during Li+ insertion, and XRD and XPS analysis help understand the Li-ion storage mechanism under different cutoff potentials.