Evaluation of the electrochemical characteristics of silicon/lithium titanate composite as anode material for lithium ion batteries

Structure and conductivity enhanced treble-shelled porous silicon as an anode for high-performance lithium-ion batteries

Silicon is regarded as the next generation anode material for lithium-ion batteries because of its high specific capacity, low intercalation potential and abundant reserves. However, huge volume changes during the lithiation and delithiation processes and low electrical conductivity obstruct the practical applications of silicon anodes. In this study, a treble-shelled porous silicon (TS-P-Si) structure was synthesized via a three-step approach. The TS-P-Si anode delivered a capacity of 858.94 mA h g⁻¹ and a capacity retention of 87.8% (753.99 mA h g⁻¹) after being subjected to 400 cycles at a current density of 400 mA g⁻¹. The good cycling performance was due to the unique structure of the inner silicon oxide layer, middle silver nano-particle layer and outer carbon layer, leading to a good conductivity and a decreased volume change of this silicon-based anode.

In this paper, a treble-shelled porous silicon structure is synthesized through three-step approach to enhance the structural stability and conductivity.

Transport Properties of Nanostructured Li2TiO3 Anode Material Synthesized by Hydrothermal Method

Li2TiO3 nanopowders were synthesized by hydrothermal process using anatase TiO2 and LiOHH2O as raw materials. Li2TiO3 crystallizes in the layered monoclinic structure (space group C2/c) with average crystallite size of 34 nm. Morphology, elemental composition and local structure of products were carried out using high-resolution transmission electron microscopy, field-emission scanning electron microscopy, Raman and Fourier transform infrared spectroscopy. Transport properties investigated by d.c. (4-probe measurements) and a.c. (complex impedance spectroscopy) show the activation energy of 0.71 and 0.65 eV, respectively. The ionic transport properties of Li+ ions in nanocrystalline Li2TiO3 characterized by cyclic voltammetry and impedance spectroscopy validate the good electrochemical properties of this anode material for lithium-ion batteries.

Transport Properties of Nanostructured Li2TiO3 Anode Material Synthesized by Hydrothermal Method

Li2TiO3 nanopowders were synthesized by hydrothermal process using anatase TiO2 and LiOH H2O as raw materials. Li2TiO3 crystallizes in the layered monoclinic structure (space group C2/c) with average crystallite size of 34 nm. Morphology, elemental composition and local structure of products were carried out using HRTEM, FESEM, EDS, Raman and FTIR spectroscopy. Transport properties investigated by d.c. (4-probe measurements) and a.c. (complex impedance spectroscopy) show the activation energy of 0.71 and 0.65 eV, respectively. The ionic transport properties of Li+ ions in nanocrystalline Li2TiO3 characterized by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) validate the good electrochemical properties of this anode material for lithium-ion batteries.

A New Strategy for Maximizing the Storage Capacity of Lithium in Carbon Materials

A novel strategy for maximizing the lithium storage capacity of carbon materials is reported. To redesign the interior structure, a large amount of Li, 4 wt%, is doped into the carbon during its synthesis. The Li-doped carbon is subsequently annealed, during which the diffusion of Li induces a disordered structure, thereby generating many nanocavities. The diffused Li atoms aggregate into a superdense state within the carbon structure; when the Li agglomerates escape from the carbon during the delithiation process, new void spaces are created at their location. Thus, the interior of carbon is evacuated to form a new structure capable of storing a large amount of Li, realizing a high reversible capacity during charging. At a rate of 1 C, the average reversible capacity of the material is three times higher than that of commercial graphite, with a stable cycling performance over 300 cycles. This is a remarkably improved Li storage performance for pure carbon, without the need for the silicon, tin, or transition metal oxide, that are becoming popular as next-generation materials. Therefore, this novel strategy can potentially aid in the design of high-performance materials via better carbon material design and combinations with other types of materials.

Facile synthesis of a heterogeneous Li2TiO3/TiO2 nanocomposite with enhanced photoelectrochemical water splitting

A novel Li₂TiO₃/TiO₂ nanocomposite was synthesized by a combination of anodization and hydrothermal processes and an enhanced photoelectrochemical response was demonstrated.

Li4Ti5O12 nanosquares@ultrathin carbon nanofilms on a large scale with enhanced properties in lithium-ion batteries

Ultra-thin C-LTO nanosquares with high crystallinity were synthesized on a large scale and their electrochemical performance was measured in 18 650 batteries.

Influence of copper addition for silicon–carbon composite as anode materials for lithium ion batteries

A series of porous Si–C and Si–C/Cu composites have been successfully fabricated by a simple sol–gel and pyrolysis process.

A low-cost and advanced SiOx–C composite with hierarchical structure as an anode material for lithium-ion batteries

By using low-cost methods, a SiO_x–C composite with hierarchical structure was applied as a high performative anode material for lithium-ion batteries.