Patent ID: 6033798
Filing Date: 2000-03-07
Classification: C01G,C01P,G01N,H01M,Y02E

Abstract:
A method of determining the charge and/or discharge capacities of non-aqueous batteries with an operating voltage of about 4 volts, comprising:determining an inverse molar susceptibility value at each of a plurality of different temperatures for a plurality of lithium manganese spinel oxide cathode materials having different respective Mn valencies;plotting the inverse molar susceptibility values against temperatures for each of the plurality of lithium manganese spinel oxide cathode materials;determining values of at least one of two paramagnetic parameters, Weiss temperature and effective magnetic moment, by obtaining the temperature dependence of the above inverse molar susceptibility from a plot derived from the Curie-Weiss law, said Weiss temperature corresponding to a temperature value extrapolated to a zero point of the inverse molar susceptibility and said effective magnetic moment being obtainable from the gradient value of the plot;producing plural rechargeable lithium batteries in which lithium manganese spinel oxides with well-defined Mn valencies are used as cathode materials, and finding at least one of the charge or discharge capacities around 4 V for each of the batteries;providing at least one correlation curve between the above-found charge and/or discharge capacities and the above-found at least one paramagnetic parameter value; andobtaining charge and/or discharge capacities for a rechargeable lithium battery containing a lithium manganese spinel oxide whose charge and/or discharge capacities are being sought from said at lest one determined paramagnetic parameter value using said at least one correlation curve.