ESTIMATION METHOD OF STATE OF CHARGE OF POWER STORAGE DEVICE AND ESTIMATION SYSTEM OF STATE OF CHARGE OF POWER STORAGE DEVICE

A capacity measurement system of a secondary battery that estimates an SOC with high estimation accuracy in a short time at low cost is provided. The capacity measurement system of a secondary battery is an estimation system of a state of charge of a power storage device that includes a unit for acquiring time-series data of a voltage measured value and a current measured value of a first power storage device; a unit for normalizing the time-series data of the voltage measured value; a unit for normalizing the time-series data of the current measured value; a database creation unit for creating a database where an SOC of the first power storage device is linked to superimposed data of time-series data of a time axis corresponding to a vertical axis and time-series data of a time axis corresponding to a horizontal axis; and a neural network unit where a neural network is constructed using the database created in advance as learning data, superimposed data of time-series data of a time axis corresponding to a vertical axis and time-series data of a time axis corresponding to a horizontal axis of a second power storage device is input, and an estimated SOC value of the second power storage device is output.