Abnormality detecting device for a system including battery assemblies

1. An abnormality detecting device configured to detect an abnormality in a system including a plurality of battery assemblies each including a plurality of cells connected in series, the abnormality detecting device comprising:

a connecting component configured to connect and disconnect adjacent two of the battery assemblies; and

a detachment detector configured to detect whether or not the connecting component has been detached,

wherein the detachment detector comprises:

a cell voltage monitor configured to detect a terminal voltage of each of the cells of the two battery assemblies and to discharge each of the cells of the two battery assemblies;

an interface unit configured to connect each of the cells of the two battery assemblies to the cell voltage monitor,

wherein the cell voltage monitor includes a semiconductor integrated circuit including a first voltage detection terminal, a second voltage detection terminal, a first discharge terminal, and a second discharge terminal,

wherein the semiconductor integrated circuit is connected across the two battery assemblies connected to each other via the connecting component,

wherein the interface unit is configured to:

connect a first end of the connecting component to the first voltage detection terminal of the semiconductor integrated circuit;

connect a second end of the connecting component to the second voltage detection terminal of the semiconductor integrated circuit;

connect a first branch point that is located between the first end of the connecting component and the first voltage detection terminal to the first discharge terminal of the semiconductor integrated circuit;

connect a second branch point that located between the second end of the connecting component and the second voltage detection terminal to the second discharge terminal of the semiconductor integrated circuit,

wherein the interface unit comprises:

a first diode directly connected to the first branch point; and

a second diode directly connected to the first diode and the second branch point, and

wherein the detachment detector comprises:

a third diode directly connected to a first point and a second point, the first point being located between the first branch point and the first discharge terminal and the second point being located between the second branch point and the second discharge terminal.

2. The abnormality detecting device according to claim 1 ,

wherein the detachment detector comprises:

a current generator configured to pass current through the two battery assemblies; and

a determiner configured to determine whether the connecting component is attached or detached, based on voltages between a plurality of nodes of the interface unit to each which two cells are connected, the two cells being adjacent to a first end and a second end of the connecting component, respectively.

3. The abnormality detecting device according to claim 2 ,

wherein a current passed by the current generator operates the cell voltage monitor.

4. The abnormality detecting device according to claim 2 ,

wherein the interface unit includes a plurality of resistances configured to connect the cells of the battery assemblies to terminals of the cell voltage monitor, respectively, and

wherein one end of the third diode is connected to an intermediate node of a first resistance among the resistances, and another end of the third diode is connected to an intermediate node of a second resistance among the resistances.

5. The abnormality detecting device according to claim 2 ,

wherein the first diode and the second diode are connected in series opposite to each other between the first branch point and the second branch point.

6. The abnormality detecting device according to claim 2 ,

wherein a current passed by the current generator operates the cell voltage monitor.

7. The abnormality detecting device according to claim 2 ,

wherein the connecting component is a detachable connector.

8. The abnormality detecting device according to claim 1 ,

wherein the connecting component is a detachable connector.

9. The abnormality detecting device according to claim 1 ,

wherein the interface unit includes a first resistor directly connected to the first branch point and the first point, and a second resistor directly connected to the second branch point and the second point.