Nondestructive method for measuring active area of active material

A method for measuring an active area of a non-destructive active material, the method comprising:

• manufacturing three electrodes comprising a first electrode coated with an electrode mixture containing an electrode active material and a conductive material, a second electrode coated with an electrode mixture containing the electrode active material as its main component and not containing the conductive material, and a third electrode coated with an electrode mixture containing no electrode active material and containing the conductive material as its main component;
• manufacturing three monocells using the first, second and third electrodes;
• measuring a capacitance of each of the first, second and third electrodes used in the monocells;
• and
• calculating an active area (m2) of the electrode active material by a following Formula 1,
• AA.M=(Ctotal−CCNT*ACNT)/CA.M [Formula 1]
• in Formula 1,
• AA.M denotes the active area (m2) of the electrode active material coated on the first electrode,
• ACNT denotes a surface area (m2) of the conductive material coated on the first electrode,
• Ctotal denotes a capacitance (F) of the first electrode,
• CCNT denotes a capacitance per unit surface area of the conductive material (F/m2), and
• CA.M denotes the capacitance per unit surface area of the electrode active material (F/m2).