A battery pack (110) comprises a discharge current acquisition component (11), a status acquisition component (12), a similarity calculator (112), and a use application determination component (113). The discharge current acquisition component (11) acquires the current value of a discharge current supplied to a vehicle (30). The status acquisition component (12) acquires the speed of the vehicle (30) operated by the current value acquired by the discharge current acquisition component (11). The similarity calculator (112) compares the current value acquired by the discharge current acquisition component with the speed of the vehicle (30) acquired by the status acquisition component (12), and calculates the similarity between the two. The use application determination component (113) determines whether or not the battery pack is being used for something other than its intended use application, according to the similarity calculated by the similarity calculator (112).