Improved Performance of Li-Added Mo–Nb Oxide as the Anode for Li-Ion Batteries with N-Carbon Coating

Abstract

High capacity, fast charging/discharging, safe operation, and long cycle-time are the essential properties of lithium-ion batteries (LiBs) for electric vehicles and large-scale energy storage applications. To meet those properties, an alternative anode has to be developed to replace the traditional graphite electrode. This study aims to demonstrate the effectiveness of Mo–Nb oxide (MNO)-based anode material for fast charging LiB. LiOH is primarily used not only as a source of Li dopant but also as a sintering agent during the solid-state reaction to lower the calcination temperature. After lithium doping, the electrochemical test shows that the C-rate coefficients and capacity retention increase from 12 to 20 C and from 23 to 70.3%, respectively. To further improve the electronic conductivity, Li-added MNO (Li-MNO) is coated with a conductive nitrogen-doped carbon (NC) layer by the pyrolysis method under an argon atmosphere. With more excellent electronic conductivity, the Li-MNO/NC delivers higher specific capacities of 112, 76, and 42 mAhg–1 at high C-rates of 5, 10, and 20 C, respectively, as compared to the Li-MNO with capacities of 75, 50, and 22.8 mAhg–1 at the same C-rates. It retains 70% of its capacity after 100 cycles.

Single-Step Synthesis of Fe-Doped Ni3S2/FeS2 Nanocomposites for Highly Efficient Oxygen Evolution Reaction

“…78-886. The crystal properties of NSF- n were further investigated by the XRD Rietveld refinement technique according to our recent study, and the results are shown in Figure S1 and Table . It can be clearly seen from Table that the lattice parameters ( a and c ) and the cell volume expand after the addition of FeCl 2 .…”

Imaging the Surface/Interface Morphologies Evolution of Silicon Anodes Using in Situ/Operando Electron Microscopy

“…Recent research has demonstrated improving the cyclability and capacity retention of Si nanoparticles (Si-NPs) by covering them with nanometer-thick coating layers. − The function of the coating layer, meanwhile, is far from apparent from the perspectives of surface chemistry and electrochemical-mechanical impact. Recently, the lithiation/delithiation kinetics of Si-NPs covered with the conductive polymer polypyrrole were examined using in situ transmission electron microscopy (PPy) .…”

A V-doped W3Nb14O44 anode in a Wadsley–Roth structure for ultra-fast lithium-ion half/full batteries

“…The key is to explore materials with continuous crystal structures for excellent conductivity, open host lattices for fast Li + diffusion, and suitable lithiation potentials (41.0 V vs. Li + /Li) for adequate safety. Combined with the above requirements, titanium-based oxides (such as Li 4 Ti 5 O 12 , 8,9 TiO 2 10 ) and niobium-based oxides (such as Nb 2 O 5 , 6,11,12 Ti/Nb oxides, [13][14][15][16][17][18][19] Mo/Nb oxides, 20,21 and W/Nb 1,5,[22][23][24][25][26] ) have been considered as promising candidates for high-rate anodes at the micrometer scale. The operating voltage (1.0-2.0 V vs. Li + /Li) of these materials limits the formation of lithium dendrite and SEI film even at very high rate, simultaneously suppresses the degradation of electrolyte, which results in a good security performance.…”