Method of diagnosing a malfunction in an abnormal voltage detecting apparatus, secondary battery system, and hybrid vehicle

A secondary battery system comprising:

• a secondary battery;
• an abnormal voltage detecting apparatus which is able to be electrically connected to and disconnected from the secondary battery and detects the voltage of the secondary battery and determines that the voltage of the secondary battery is abnormal if the detected voltage value is outside of a normal voltage range;
• and
• a direct current voltage generating portion which i) is able to be electrically connected to and disconnected from the abnormal voltage detecting apparatus, ii) is able to generate direct current voltage that has a predetermined voltage value that is outside of the normal voltage range, and iii) is different than the secondary battery,
• wherein it is determined that there is a malfunction in the abnormal voltage detecting apparatus if the abnormal voltage detecting apparatus does not determine that the voltage of the secondary battery is abnormal when the abnormal voltage detecting apparatus is electrically disconnected from the secondary battery and connected to the direct current voltage generating portion, and the direct current voltage generating portion applies the direct current voltage to the abnormal voltage detecting apparatus,
• wherein the direct current voltage generating portion is structured to be able to generate direct current voltage that has a constant voltage value that is outside of the normal voltage range,
• wherein the secondary battery system further comprises:
• a converting apparatus which i) is able to convert voltage from an external power supply into the direct current voltage, ii) is able to be electrically connected to the abnormal voltage detecting apparatus, and iii) is provided in the direct current voltage generating portion;
• and
• a connecting portion which is able to be electrically connected to the converting apparatus and the external power supply, and electrically connects the converting apparatus to the external power supply,
• wherein when the connecting portion is electrically connected to the external power supply, the secondary battery system breaks the electrical connection between the abnormal voltage detecting apparatus and the secondary battery, and electrically connects the abnormal voltage detecting apparatus to the converting apparatus and the connecting portion.