Rechargeable lithium battery with spinel-related λ-MnO2 III. Scaling-up problems associated with LiMn2O4 synthesis

The scaling-up problems connected with the LiMn2O4 synthesis were studied. A strong effect of the mass of the starting materials and of the air flow rate through the furnace during the synthesis on the specific capacity was observed. The increase of the batch amount brings about a reduction in the specific surface area of the product, which cannot be compensated by grinding because it leads to considerable reduction of its electrochemical utilization. The very fast or slow cooling of the synthesized material have a negative effect on the specific capacity. The process of preparation of LiMn2O4 spinel with high electrochemical performance is a rather complex procedure, but it is possible to obtain a product, which is capable to exchange reversibly up to 0.9 equiv. Li per mole.