BATTERY DETERIORATION ESTIMATION METHOD

A battery deterioration estimation method according to the present disclosure is a battery deterioration estimation method for a battery that is installed in a vehicle and supplies power to a motor, and includes processing of performing weighting of deterioration level performance data of the battery that is accumulated in advance, by performing weighting in accordance with similarity as to supplementary information regarding an estimation object battery, generating a trained model that takes usage history information of the battery as input and outputs deterioration level of the battery, by performing machine learning regarding the deterioration level performance data weighted in the processing as training data, and estimating the deterioration level of the estimation object battery using the trained model, based on the usage history information regarding the estimation object battery.