Structural, morphological, impedance and magnetic studies of nanostructured LiNi0.45M0.1Mn0.45O2 (MCu and Al) cathode materials for lithium-ion batteries

Layered structure LiNi0.45M0.1Mn0.45O2 (MCu and Al) cathode materials for lithium-ion batteries are synthesized by sol–gel auto combustion method. The structural, morphological, electrical and magnetic properties are examined by X-ray diffraction (XRD), field effect scanning electron microscope FESEM, FT-IR, EIS and ESR. XRD data revealed the rhombohedral and α-NaFeO2 structure with a space group R-3m. The electrical conductivity, dielectric constant, and dielectric loss are measured in the room temperature at a frequency ranging from 20 Hz to 1 MHz. The electrical conductivity of the compound is measured by AC impedance. An effective improvement in the electrical conductivity of order 5.42 × 10−6 S/cm is observed for the copper doped LNMO compounds. ESR spectra is recorded at room temperature on a Bruker EMX model X-band spectrometer operating at a frequency of 9.50 GHz. The critical dopants of Cu, with minimum g-factor and maximum line-width (W) are observed. •X-ray diffraction analysis confirmed phase formation and rhombohedral (α-NaFeO2) structure with a space group R-3m.•Surface morphological studies revealed that the shape of the particles was polyhedral within the size of 200 nm.•Aluminum doping shrank the lattice and increased the crystallinity and the particle size.•The diameter of Rb decreased at room temperature showing the semi-conducting nature of these materials.•Among the prepared samples, Cu showed maximum conductivity of 6.74 × 10−5 at room temperature (30 °C).