An abnormality detection device comprising: a temperature detection unit that includes a resistor section which varies a resistance value depending on a temperature of a storage battery; a resistance detection unit configured to detect a resistance value of the resistor section; a short-circuit unit configured to short-circuit the resistor section, an overvoltage detection unit configured to detect whether or not an overvoltage has occured in the storage battery, and a voltage control unit configured to control a voltage of the storage battery, wherein the short-circuit unit short-circuits the resistor section when it is detected that an overvoltage has occurred in the storage battery by the overvoltage detection unit, and wherein when the voltage of the storage battery is equal to or less than a lower limit voltage (S07: YES), the voltage control unit determines whether or not a duration of a state in which a resistance value of the resistor section is lower than a predetermined threshold value (S06: YES) reaches a first time period or more, and wherein, if the resistance value of the resistor section increases to the predetermined threshold value or more before the first time period has elapsed (S09: NO), the process ends, whereas, if the resistance value of the resistor section increases to the predetermined threshold value or more after the first time period has elapsed (S09: YES), the voltage control unit determines that a short circuit occurs due to any abnormality in the resistor section and discharges the storage battery so as to reduce a voltage of the storage battery to a predetermined lower limit voltage. a temperature detection unit that includes a resistor section which varies a resistance value depending on a temperature of a storage battery; a resistance detection unit configured to detect a resistance value of the resistor section; a short-circuit unit configured to short-circuit the resistor section, an overvoltage detection unit configured to detect whether or not an overvoltage has occured in the storage battery, and a voltage control unit configured to control a voltage of the storage battery, wherein the short-circuit unit short-circuits the resistor section when it is detected that an overvoltage has occurred in the storage battery by the overvoltage detection unit, and wherein when the voltage of the storage battery is equal to or less than a lower limit voltage (S07: YES), the voltage control unit determines whether or not a duration of a state in which a resistance value of the resistor section is lower than a predetermined threshold value (S06: YES) reaches a first time period or more, and wherein, if the resistance value of the resistor section increases to the predetermined threshold value or more before the first time period has elapsed (S09: NO), the process ends, whereas, if the resistance value of the resistor section increases to the predetermined threshold value or more after the first time period has elapsed (S09: YES), the voltage control unit determines that a short circuit occurs due to any abnormality in the resistor section and discharges the storage battery so as to reduce a voltage of the storage battery to a predetermined lower limit voltage.