A pure NiFe2O4 spinel has been prepared from an Ni-Fe2C+Fe3C+LDHs precursor under mild conditions for use as the anode material in Liion batteries. XRD, elemental analysis and a combination of TG-DTG-DTA and evolved gas mass spectrometry (EGMS) were carried out to characterize the calcined products. The main factors, affecting the electrochemical performance of the materials, were investigated. The material calcined at 700℃ for 3 h performs best with an initial discharge capacity of 1239 mAh g-1 and a reversible capacity of 701 mAh g-1. The major advantage of the LDHs precursor method for the synthesis of NiFe2O4 is that it uses a readily available precursor and affords a spinel with a small particle size and uniform distribution of metal cations, hence, resulting in a good electrochemical performance.

The pillared layered Li1-2xCaxCoO2 has been obtained for the first time by a molten salt ion exchange reaction. The X-ray diffraction data of the materials show that they are single phase and retain the layered a-NaFeO2 type structure. The electrochemical testing of Li1-2xCaxCoO2 cells with an upper cutoff potential of 4.5 and 4.7 V (vs. LiC/Li) show that the specific capacity of the oxides have been increased, respectively, to 175 and 211 mAh g-1, and retain better charge-discharge cycling performance. The XRD data shows these improvements are attributed to the pillaring role of Ca2C which helps to suppress unwanted phase transition.

Nanosized orthorhombic LiMnO2 (o-LiMnO2) with high purity and good crystallinity has been synthesized by a simple process under mild conditions (80℃) involving controlled oxidation of Mn (OH) 2 followed by in situ ion exchange of lithium ions with the resulting intermediate MnOOH (in situ oxidation-ion exchange). By studying the effects of varying the lithiating agent, the oxidant and washing conditions, a mechanism for the synthesis of nano o-LiMnO2 by this method has been proposed. Nano o-LiMnO2 obtained by in situ oxidation–ion exchange has a high capacity with an initial discharge capacity of 220 mAh g-1 and a good cycling performance with a reversible capacity of 194 mAh g-1 after 30 cyclings, indicating that it is a potential synthetic method for the positive electrode material of lithium ion secondary batteries.