BATTERY DEGRADATION EVALUATION SYSTEM, BATTERY DEGRADATION EVALUATION METHOD, AND BATTERY DEGRADATION EVALUATION PROGRAM

A battery degradation evaluation system (10) comprises an acquisition section (22, 30), a derivation section (42), and an evaluation section (44). The acquisition section (22, 30) acquires state quantities of a battery (20) mounted at a vehicle (14). The derivation section (42), based on the state quantity acquired by the acquisition section and a pre-specified computation model, derives each of a short-term degradation probability of the battery (20) degrading in a pre-specified short period, a medium-term degradation probability of the battery (20) degrading in a medium period that is longer than the short period, and a long-term degradation probability of the battery (20) degrading in a long period that is longer than the medium period. The evaluation section (44) evaluates degradation of the battery (20) based on derivation results from the derivation section (42), sets a higher weighting for a combined degradation probability for the short period and the medium period when a number of state quantities is smaller, the combined degradation probability being calculated from the long-term degradation probability, and sets a higher weighting for the short-term degradation probability when the number of state quantities is larger. The state quantities being used as data for learning of the computation model.