CPC H01G 11/84 (2013.01) [G01R 27/2605 (2013.01); H01G 11/06 (2013.01); H01G 11/34 (2013.01); H01G 11/50 (2013.01); H01G 11/52 (2013.01); H01M 4/382 (2013.01); H01M 10/052 (2013.01); H01M 10/0525 (2013.01)] | 19 Claims |
1. A current separation method of a nonaqueous lithium power storage element, wherein
the nonaqueous lithium power storage element comprises a cell comprising: a positive electrode precursor that comprises a positive electrode active material layer comprising lithium carbonate and activated carbon; a negative electrode that comprises a negative electrode active material layer comprising a negative electrode active material capable of occluding and releasing lithium; a separator arranged between the positive electrode precursor and the negative electrode; and an electrolyte solution, and the method comprises:
(a) calculating a capacitor current density (ic) and an electrode reaction current densities of electrode reactions 1 to N (iR1 to iRN) of the cell based on positive electrode potential (E) and current bulk current density (i) of the cell that are measured during doping of the cell,
(b) the doping condition setting step of setting doping conditions including cell temperature and input voltage;
(c) the measurement step of measuring a positive electrode potential (E) and a bulk current density (i) of the cell while applying the input voltage to the cell;
(d) the current density calculation step of, with an assumption of the positive electrode potential (E) at the time of modifying the system time by Δt, calculating the capacitor current density (ic) of the cell and calculating, based on the Butler-Volmer equation and the diffusion equation, current densities of electrode reactions 1 to N (iR1 to iRN), wherein, N represents an integer of 3 or larger, including an electrode reaction 1 in which lithium carbonate is decomposed to release lithium ions and electrons;
(e) the positive electrode potential correction step of correcting the assumed positive electrode potential (E) such that a total current density of the capacitor current density (ic) and the current densities of the respective electrode reactions (iR1 to iRN) is equal to the bulk current density (i), and thereby obtaining a corrected positive electrode potential (E); and
(f) the current separation step of repeating the steps (d) and (e) while modifying the system time such that the total current density converges to the bulk current density (i).
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