METHOD FOR PREDICTING DISCHARGING CAPACITY AND VOLTAGE OF LITHIUM BATTERY UTILIZING LITHIUM-MANGANESE SPINEL CATHODE MATERIAL

摘要

PROBLEM TO BE SOLVED: To establish a method for a positive electrode material evaluation by which the charging and discharging capacity and the voltage of a lithium ion battery manufactured using the material is quickly estimated by employing magnetic measurement sensitive to valence and ion distribution of Mn ion in the case of solo evaluation of a positive material for a lithium secondary battery. SOLUTION: The charging and discharging capacity and the voltage of a lithium secondary battery using a lighium-manganese spinel cathode material is estimated using two magnetic parameters: effective magnetic moment and Weiss temperature; calculated by analysis of the temperature dependability coefficient measurement data of the magnetic character of the lithium-manganese spinel positive material. Or, the capacity near 4V or 3V on a charging and discharging curve in the case the positive material is used as a positive electrode for a lithium battery is estimated by self- magnetization calculated by the magnetic field and temperature coefficient measurement data analysis of magnetization of the lithium-manganese spinel positive material at low temperature (80K or lower).