LEARNING METHOD, STATE ESTIMATION METHOD, AND STATE ESTIMATION DEVICE FOR STATE ESTIMATION MODEL OF SECONDARY BATTERY

A learning method of a state estimation model includes training the state estimation model to learn a relationship of state estimation input data obtained by preprocessing terminal currents and terminal voltages of a secondary battery with a charge rate or a deterioration degree of the secondary battery. The state estimation input data includes time-series data of: difference gradients of terminal voltage differences with respect to terminal current differences; open circuit voltages; open circuit voltage change amounts; and integrated current values of the terminal currents.