Method for manufacturing secondary battery

A method for manufacturing a secondary battery, comprising the steps of:

• measuring a first voltage V1 for each of the plurality of battery assemblies, the first voltage V1 being an inter-terminal voltage before an aging process;
• performing the aging process for each of a plurality of battery assemblies;
• measuring a second voltage V2 for each of the plurality of battery assemblies, the second voltage V2 being an inter-terminal voltage after the aging process;
• calculating a voltage difference ΔV between the first voltage V1 and the second voltage V2 for each of the plurality of battery assemblies;
• plotting the first voltage V1 and the voltage difference ΔV in each of the plurality of battery assemblies on coordinates having the first voltage V1 as a first axis and the voltage difference ΔV as a second axis, thereby acquiring a regression curve indicating a distribution tendency of the plurality of battery assemblies on the coordinates;
• and
• performing pass/fail determination for each of the plurality of battery assemblies based on the regression curve.