Structural and conductivity studies on LiNiPO4 synthesized by the polyol method

► LiNiPO4 was prepared by polyol method calcined at 650°C for 4h. ► 1,2 Propanediol, polyol medium shows better crystalline nature of LiNiPO4. ► Sintering temperature was optimized at 650°C. ► The maximum conductivity was found to be 4.36×10−6 at 300°C. LiNiPO4 powders were prepared by the polyol method using 1,2 propanediol and ethylene glycol as a polyol medium. XRD studies reveal the formation of LiNiPO4 with high crystalline nature even at a low calcination temperature of 650°C and low calcination time. TGA analysis confirms that the LiNiPO4 has been formed at 650°C and consistent with XRD results. It has also been found that the crystallite size is in the order of nanometer. The spherical shaped particles connected with each other have been observed from SEM analysis. The AC impedance spectroscopy measurements have been carried out in the frequency range of 42Hz–1MHz over the temperature ranges of 200–425°C. The low activation energy has been found for the sample sintered at 650°C which facilitates the ionic motion. Impedance and dielectric relaxation studies have also been performed for LiNiPO4 sintered at 650°C.