BATTERY CHARACTERISTIC ESTIMATION DEVICE, BATTERY CHARACTERISTIC ESTIMATION METHOD, AND STORAGE MEDIUM

A battery characteristic estimation device including a storage medium that stores computer-readable instructions, and a processor coupled to the storage medium, the processor executing the computer-readable instructions to: acquire time-series data of at least a voltage and current of a secondary battery having a positive electrode containing a positive electrode active material and a negative electrode containing a negative electrode active material; store a reference positive electrode OCP curve, and a reference negative electrode OCP curve; convert the reference positive electrode OCP curve into a positive electrode OCP curve in accordance with a first parameter group, convert the reference negative electrode OCP curve into a negative electrode OCP curve in accordance with a second parameter group, and estimate an OCV curve on the basis of a difference between the positive electrode OCP curve and the negative electrode OCP curve; and optimize the first parameter group and the second parameter group.