SECONDARY BATTERY SYSTEM

To solve the problem of the occurrence of false detection in a conventional secondary battery system.SOLUTION: A secondary battery system comprises: a positive electrode-side power wire W2 to be connected to a positive electrode terminal of a load circuit of a vehicle; a precharge circuit including a precharge resistance R1 connected in series between a driving battery 10 and the positive electrode-side power wire W2, and a first relay switch SW1; a third relay switch SW3 provided in parallel with the precharge circuit and having one end connected to a negative electrode terminal of the driving battery 10 through a negative electrode-side battery wire W3; and an abnormality detecting circuit 13 for detecting a voltage difference between the negative electrode-side battery wire W3 and the positive electrode-side power wire W2 as a detection voltage Vs, and detecting an abnormality of the first relay switch SW1 to the third relay switch SW3 on the detection voltage Vs.SELECTED DRAWING: Figure 1 【課題】従来の二次電池システムでは、誤検出が発生する問題があった。【解決手段】本発明の二次電池システムは、車両の負荷回路の正極端子に接続される正極側電力配線Ｗ２と、駆動用バッテリ１０と正極側電力配線Ｗ２との間に直列に接続されるプリチャージ抵抗Ｒ１と、第１のリレースイッチＳＷ１と、を含むプリチャージ回路と、プリチャージ回路と並列に設けられ、駆動用バッテリ１０の負極端子に負極側バッテリ配線Ｗ３を介して一端が接続される第３のリレースイッチＳＷ３と、負極側バッテリ配線Ｗ３と正極側電力配線Ｗ２との電圧差を検出電圧Ｖｓとして検出し、検出電圧Ｖｓに基づき第１のリレースイッチＳＷ１から第３のリレースイッチＳＷ３の異常を検出する異常検出回路１３と、を有する。【選択図】図１