Patent ID: 7799461

Claim:
A high capacity, high charge rate lithium secondary cell, comprising: a high capacity lithium-containing positive electrode in electronic contact with a positive electrode current collector, the current collector in electrical connection with an external circuit; a high capacity carbon-containing negative electrode in electronic contact with a negative electrode current collector, said current collector in electrical connection with an external circuit; a separator positioned between and in ionic contact with the cathode and the anode; and an electrolyte in ionic contact with the positive and negative electrodes, wherein the charge capacity per unit area of the positive and negative electrodes each are at least 0.75 mA-h/cm 2 ; and the total area specific impedance for the cell and the relative area specific impedances for the positive and negative electrodes are such that the area specific impedance of the positive electrode is at least about 3 times of the area specific impedance of the negative electrode, and that during charging at greater than or equal to 4 C, the negative electrode potential is above the potential of the Li/Li + electrochemical couple.