A vehicle comprising: a battery pack in which a plurality of alkaline secondary batteries are connected in series; a motor configured to generate power for traveling of the vehicle by receiving discharge electric power of the battery pack; a voltage sensor configured to detect a voltage value of each of the alkaline secondary batteries; a current sensor configured to detect a current value of the battery pack; an engine configured to generate power for the traveling of the vehicle; and a controller configured to: (i) determine whether or not one of the alkaline secondary batteries is in an over-discharge state based on at least the voltage value of the one of the alkaline secondary batteries or a voltage difference, the voltage difference being a difference between the voltage value of the one of the alkaline secondary batteries and a predetermined reference voltage value, and (ii) perform the traveling of the vehicle by using the power of the motor by discharging the battery pack while decomposing electrolytic solution contained in the alkaline secondary batteries in the over-discharge state after the controller determines that the one of the alkaline secondary batteries is in the over-discharge state, characterized in that the controller is configured to decrease an upper limit electric power value while an integrated value is lower than a first threshold when the controller determines that the one of the alkaline secondary batteries is in the over-discharge state, the upper limit electric power value allowing the discharging of the battery pack, and the integrated value being obtained by integrating the current value while performing the discharging when the one of the alkaline secondary batteries is in the over-discharge state, and the controller is configured to perform the traveling of the vehicle by using the power of the engine, without using the power of the motor, when the integrated value is equal to or higher than the first threshold. a battery pack in which a plurality of alkaline secondary batteries are connected in series; a motor configured to generate power for traveling of the vehicle by receiving discharge electric power of the battery pack; a voltage sensor configured to detect a voltage value of each of the alkaline secondary batteries; a current sensor configured to detect a current value of the battery pack; an engine configured to generate power for the traveling of the vehicle; and a controller configured to: (i) determine whether or not one of the alkaline secondary batteries is in an over-discharge state based on at least the voltage value of the one of the alkaline secondary batteries or a voltage difference, the voltage difference being a difference between the voltage value of the one of the alkaline secondary batteries and a predetermined reference voltage value, and (ii) perform the traveling of the vehicle by using the power of the motor by discharging the battery pack while decomposing electrolytic solution contained in the alkaline secondary batteries in the over-discharge state after the controller determines that the one of the alkaline secondary batteries is in the over-discharge state, (i) determine whether or not one of the alkaline secondary batteries is in an over-discharge state based on at least the voltage value of the one of the alkaline secondary batteries or a voltage difference, the voltage difference being a difference between the voltage value of the one of the alkaline secondary batteries and a predetermined reference voltage value, and (ii) perform the traveling of the vehicle by using the power of the motor by discharging the battery pack while decomposing electrolytic solution contained in the alkaline secondary batteries in the over-discharge state after the controller determines that the one of the alkaline secondary batteries is in the over-discharge state, characterized in that the controller is configured to decrease an upper limit electric power value while an integrated value is lower than a first threshold when the controller determines that the one of the alkaline secondary batteries is in the over-discharge state, the upper limit electric power value allowing the discharging of the battery pack, and the integrated value being obtained by integrating the current value while performing the discharging when the one of the alkaline secondary batteries is in the over-discharge state, and the controller is configured to perform the traveling of the vehicle by using the power of the engine, without using the power of the motor, when the integrated value is equal to or higher than the first threshold.