| 摘要 |
A battery system comprising a plurality of cells 104 arranged in series in a battery pack 103, a first contactor relay switch (107,108) connected to a positive end 110 of battery pack 103 and a second contactor relay switch 106 connected to a negative end 111 of battery pack 103. A controller 114 is configured to measure a first voltage between the positive terminal 101 and a reference point, a second voltage between the negative terminal 102 and the reference point and a third voltage between a location 105 part way along the plurality of cells 104 and the reference point. A failure state of the battery is determined from the measured voltages. The failure state may be a failure of one or both of the contactor relay switches (106, 107, 108) or leakage of current from the battery system to the reference point. Embodiments are included in which the battery system is used to detect symmetric current leakage from the high voltage terminals of a battery pack used in an electric vehicle. The reference point may be ground or the chassis of the vehicle. |
