Author(s)

Ramasamy Thirunakaran^1*, Gil Hwan Lew², Won-Sub Yoon^2*

¹CSIR-Central Electrochemical Research Institute, Karaikudi, India.
²Department of Energy Science, Sungkyunkwan University, Suwon, Republic of Korea.

LiMn₂O₄ and LiCu_xCr_yMn_2-x-yO₄ (x = 0.50; y = 0.05 - 0.50) powders have been synthesized via sol-gel method for the first time using Myristic acid as chelating agent. The synthesized samples have been taken to physical and electrochemical characterization such as thermo gravimetric analysis (TG/DTA), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), field-emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM) and electrochemical characterization viz., electrochemical galvanostatic cycling studies, electrochemical impedance spectroscopy (EIS) and differential capacity curves (dQ/dE). XRD patterns of LiMn₂O₄ and LiCu_xCr_yMn_2-x-yO₄ confirm high degree of crystallinity with good phase purity. FESEM image of undoped pristine spinel lucidly depicts cauliflower morphology with good agglomerated particle size of 50 nm while 0.5-Cu doped samples depict the pebbles morphology. TEM images of the spinel LiMn₂O₄ and LiCu_0.5Cr_0.05Mn_1.45O₄ authenticate that all the synthesized particles via sol-gel method are nano-sized (100 nm) with spherical surface and cloudy particles morphology. The LiMn₂O₄ samples calcined at 850℃ deliver the high discharge capacity of 130 mA·h/g with cathodic efficiency of 88% corresponds to 94% columbic efficiency in the first cycle. Among all four compositions studied, LiCu_0.5Cr_0.05Mn_1.45O₄ delivers 124 mA·h/g during the first cycle and shows stable performance with a low capacity fade of 1.1 mA·h/g cycle over the investigated 10 cycles.

Multi-Doping, Sol-Gel Method, Myristic Acid, Differential Capacity, Spinel Cathode

Thirunakaran, R. , Lew, G. and Yoon, W. (2016) Sol-Gel Synthesis Using Novel Chelating Agent and Electrochemical Characterization of Binary Doped LiMn₂O₄ Spinel as Cathode Material for Lithium Rechargeable Batteries. World Journal of Nano Science and Engineering, 6, 1-19. doi: 10.4236/wjnse.2016.61001.