Synthesis, Characterization, and Comparison of Electrochemical Properties of LiM[sub 0.5]Mn[sub 1.5]O[sub 4] (M=Fe, Co, Ni) at Different Temperatures

( , Co, Ni) normal spinel oxides were prepared by a citric acid assisted Pechini synthesis with different thermal treatments and compared with respect to their electrochemical performance as cathodes in lithium-ion batteries. Characterization methods include X-ray diffraction, neutron diffraction, inductively coupled plasma optical emission spectroscopy analysis, and scanning electron microscopy. While samples crystallize for and Co with the 3d cation-disordered cubic spinel-like structure ( space group), the annealed shows a partially ordered structure (belonging to the space group). The absolute discharge capacity is slightly higher for the Ni-doped samples in comparison with the Co- and Fe-doped spinels. annealed samples show an improved cyclability in comparison with the annealed samples. At elevated temperatures, Co- and Fe-doped samples show much faster degradation in comparison with the Ni-doped sample. The responsible mechanisms are discussed.