Electrochemical Characterization of Low-Cost Lithium-Iron Orthosilicate Samples as Cathode Materials of Lithium-Ion Battery

Lithium-iron-orthosilicate is one of the most promising cathode materials for Li-ion batteries due to its safety, environmental brightness and potentially low cost. In order to produce a low cost cathode material, Li2FeSiO4/C samples are synthesized via sol-gel (SG; one sample) and solid state (SS; two samples with different carbon content) methods, starting from Fe(III) as the raw materials (low pristine materials). The three samples are characterized for purity, structure, and morphology. The electrochemical tests showed the different charge-discharge behaviors of the SS and SG samples. Electrochemical behaviors were investigated in terms of voltage vs. square root of capacity diagrams and their slopes. The best results are obtained for the SS sample containing the larger amount of carbon.