Device for detecting abnormality in a secondary battery

A device for detecting abnormality in a secondary battery cell having a plurality of electrode terminals, comprising:

• an electrically-conductive connecting plate that connects each of the plurality of electrode terminals to other battery cells;
• a fastening member that fastens the connecting plate with one of the plurality of electrode terminals together;
• a metal plate, a first end of which being electrically and thermally connected to the one of the plurality of electrode terminals;
• a metal terminal joined to a second end, opposite to the first end, of the metal plate, the metal terminal being electrically and thermally joined to the one of the plurality of electrode terminals;
• temperature-detecting means placed near a fastened portion adjacent the fastening member and the metal plate, and detects temperature around the fastened portion;
• and
• abnormality judging means that judges abnormality in the fastening member on the basis of temperature detected by the temperature-detecting means, wherein
• the abnormality judging means detects looseness in the fastening member on the basis of the temperature detected by the temperature-detecting means, when a load current equal to or higher than a prescribed value is flowing from the corresponding electrode terminal to the connecting plate, and either one of the two temperature-detecting means detects temperature equal to or higher than a prescribed temperature.