METHOD AND DEVICE FOR DETERMINING STATE OF RECHARGEABLE BATTERY

A rechargeable battery state determination method determines whether a rechargeable battery (1) is in a micro-short-circuit-prone state, which is a state that is highly likely to form a micro-short circuit. The rechargeable battery state determination method includes measuring an electron transfer resistance (Rs) of the rechargeable battery by applying a voltage or current having a predetermined or higher frequency to an electrode system (2, 3) of the rechargeable battery (1), determining whether an inter-electrode distance (D) is satisfactory based on a comparison of the measured electron transfer resistance (Rs) of the rechargeable battery (1) with a predetermined lower limit threshold value (Rsmin), in which the determining whether an inter-electrode distance (D) is satisfactory including determining that the inter-electrode distance (D) is satisfactory when the measured electron transfer resistance (Rs) of the rechargeable battery (1) is greater than or equal to the lower limit threshold value (Rsmin), and determining that the rechargeable battery (1) is a conforming piece when the inter-electrode distance (D) is satisfactory.