The lithia matrix consists of a mixture of lithium oxide (Li2O) and lithium orthoborate (Li3BO3). In fact, the reduction process of 3d-metal borates involves their decomposition in metal nanograins dispersed into a lithia matrix surrounded by an organic layer responsible for the observed extra capacity. The electrochemical properties of these materials as anodes for lithium batteries were investigated and found to be similar to those of 3d-metal oxides. The electrochemical reactivity mechanism of M3B2O6 (with M = Co, Ni, and Cu) powders toward lithium was studied by a combination of transmission electron microscopy (TEM), infrared spectroscopy (IR), 11B magic angle spinning nuclear magnetic resonance (MAS NMR), and electrochemical techniques. The electrical characterization of materials developed by impedance spectroscopy solid state, allowed to determine a p-type semiconducting behaviour with conductivity values of 6.2Г—10вЃ»Ві and 2.7Г—10вЃ»вЃ· S for LiCoO2 and LiMn2O4 systems, consistent with the state of the art for such materials.

The characterization by X-Ray Diffraction (XRD), Scanning and Transmission Electron Microscopy (SEM, TEM) and X-Ray Fluorescence (XRF), allowed to evaluate the morphology and the stoichiometric compositions of solids, obtaining a concordant pure crystalline phase of LiCoO2 and LiMn2O4 oxides identified in a rhombohedral and cubic phase with punctual group R-3m (1 6 6) and Fm-3m (2 2 5) respectively. A simple combustion synthesis process was employed to obtain the nanometric oxides in powder form (crystal sizes around 5-8nm), with a number of improved surface characteristics. This paper describes the synthesis and characterization of two spinel and olivine-type multicomponent oxides based on LiMO2 and LiM2O4 systems (M=Co and Mn), which represent the current state of the art in the development of cathodes for Li-ion batteries.

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