LiCo1−yMyO2 positive electrodes for rechargeable lithium batteries: II. Nickel substituted materials grown by the citrate method

[Abstract] The layered LiCo1−yNiyO2 microcrystalline powders were synthesized by a sol–gel method using citric acid as a chelating agent in the range 0.2 ≤ y ≤ 0.8. Submicron-sized particles of the precursor were obtained at temperature below 400 °C and microcrystalline powders were grown by thermal treatment at 700 °C for 5 h in air. The carboxylic-based acid functioned such as a fuel, decomposed the homogeneous precipitate of metal complexes at low temperature, and yielded the free impurity LiCo1−yNiyO2 single-phases suitable for electrochemical applications. The synthesized products were characterized by structural, spectroscopic and thermal analyses. FT-IR measurements provide information on the growth process and the final local environment in the cationic sublattice of LiCo1−yNiyO2 solid solution. The electrochemical performance of the synthesized products in rechargeable Li cells was evaluated using non-aqueous solution 1 M LiPF6 in EC-DMC as electrolyte. The electrochemical features of a series of LiCo1−yNiyO2 compounds (0.2 ≤ y ≤ 1.0) are discussed in relation with their synthesis procedure and substitutive amount. The substitution of Ni3+ for Co3+ in LiCo1−yNiyO2 for y = 0.75 shows improvement of the specific capacity at ca. 187 mAh/g upon 32 cycles

Influence of geometric non-linearities on the free vibrations of anisotropic open cylindrical shells

Equations of motion -- Displacement functions -- Mass and linear stiffness matrices for an element -- Non-linear matrix construction -- The influence of geometric non-linearities of the walls on the natural frequencies of an open cylindrical shell

Dynamic analysis of non-uniform circular plates

Fundamental equations for circular plates -- Displacement functions -- Deformation and stress component matrices -- Stiffness and mass matrices -- Static and dynamic analysis -- Numerical calculations and discussion

Vibration analysis of anisotropic open cylindrical shells containing flowing fluid

ABSTRACT: Determination of the displacement functions -- Mass and stiffness matrices for empty finite elements -- Behaviour of the fluid-shell interaction -- Eigenvalue and eigenvector problem

Hybrid finite element analysis of circular and annular plates

Fundamental equations -- Displacement functions -- Deformation and stress component matrices -- Stiffness and mass matrices

Dynamic analysis of anisotropic open cylindrical shells

Fundamental equations for open cylindrical shells -- Displacement functions -- Stress vector -- Mass and stifness matrices for one finite element -- The global mass and stiffness matrices -- Analysis of an open shells subjected to static loads -- Free vibrations

Non-linear dynamic analysis of anisotropic cylindrical shells

Linear matrix construction -- Non-linear matrix construction -- The influence of geometric non-linearities of the walls on the natural frequencies of a cylindrical shell