Electrochemical performanceof LiMn₂O₄ with varying thickness of cathode sheet

Lithium-ion batteries are widely used as portable electrical energy storage devices because they have high energy densities and long life cycles. One of the cathode active materials used in the manufacture of Lithium-ion batteries is LiMn2O4 because of its easy and cheap manufacturing, has a long life cycle, high power applications, safe, and low toxicity of manganese basic materials. In this research, LiMn2O4 as cathode sheet has been made by doctor blade coating. This method was carried out by mixing LiMn2O4 with polyvinylidene fluoride (PVDF), Super P, and dimethylacetamide (DMAC) with weight ratio of 82.5: 10: 7.5, respectively, to obtain a well dispersed slurry. Slurry was superimposed on aluminum foil surface with various thickness of 200, 300 and 400 μm. Coin cell was assembled using electrodes, separator, lithium metal and electrolytes in the glove box. The cell battery was characterized by using cyclic voltammetry, charge discharge and electrochemical impedance spectroscopy in order to know the effect of active material thickness to cell battery performances. The results showed that active material with 400 μm in thickness had the best electrochemical performance due to a narrow and sharp reduction-oxidation peak pair, small polarization value of 0.0335 V as well as having charge and discharge capacities of 1.1249 mAh and 1.0914 mAh, respectively. Moreover, EIS result showed that 400 μm thickness of active material had highest conductivity value of 5.3922 × 10⁻⁵ Scm⁻¹. (paper)