Synthesis and improved electrochemical performance of LiMn<inf>2 – x</inf>Gd<inf>x</inf>O<inf>4</inf> based cathodes

LiMn2 – xGdxO4 (x = 0.00, 0.01 and x = 0.04) spinel active material were prepared by sol-gel method. The morphology, crystal structure, thermal stability and electrochemical properties of the synthesized samples were evaluated. Gd-doping maintains the cubic spinel structure of LiMn2O4, leads to a decrease of the average particle size, and has a strong influence on the electrochemical properties of the cathodes. LiMn2 – xGdxO4 cathode materials show two pairs of separated redox peaks, independently of the Gd-doping. After 40 charge-discharge cycles at C/2, the discharge capacity was 55.9 mAh·g− 1 and 33 mAh·g− 1 for x = 0.04 and x = 0, respectively, corresponding to a capacity retention of 80% and 70%, respectively. The Gd-doped with x = 0.04 showed improved cycling performance with respect to pristine LiMn2O4 due the smaller particle size and superior structural stability, showing its suitability for lithium-ion battery applications.