Method and system for predicting the time required for low voltage expression of a secondary battery, and aging method of the secondary battery using the same

A method for predicting a time required for low voltage expression of a secondary battery, the method comprising the steps of:

• (a) obtaining a leakage current of a battery cell of the secondary battery by the following sub-steps (a-1) to (a-3):
• (a-1) inputting a voltage of the battery cell of the secondary battery;
• (a-2) measuring a freezing resistance of the battery cell in a state where the battery cell is frozen before, after, or simultaneously with the sub-step (a-1);
• and
• (a-3) dividing the input voltage by the measured freezing resistance to thereby calculate the leakage current of the battery cell;
• (b) obtaining a discharge capacity difference for the battery cell by the following steps (b-1) and (b-2) performed before, after or simultaneously with the step (a):
• (b-1) setting a reference value of a voltage drop for selecting a low voltage defect;
• and
• (b-2) obtaining the discharge capacity difference for the battery cell between the voltage inputted and the reference value of the voltage drop for selecting the low voltage defect;
• and
• (c) dividing the discharge capacity difference by the leakage current to thereby calculate a time required for low voltage expression,
• wherein the battery cell is frozen when ionic conductivity of electrolyte of the battery cell becomes almost zero, and
• wherein the voltage in the sub-step (a-1) is an open circuit voltage (OCV) before starting an aging process.