Battery system with function of preventing abnormal voltage at output stage and control method thereof

A method of controlling a battery system for preventing an abnormal voltage at an output stage, the method comprising:

• determining whether a voltage, which is a preset voltage or more, is applied from a battery cell;
• upon determining that the voltage applied from the battery cell is the preset voltage or more, determining, by a controller of a battery management system (BMS), whether a relay switch is controllable;
• upon determining that the relay switch is not controllable, switching, by the controller, an automatic cut-off switch to be turned on to apply the voltage applied from the battery cell to an active voltage switch and a high-voltage interlock switch;
• and
• upon determining that the voltage applied from the battery cell is less than the preset voltage, controlling the active voltage switch to turn off the relay switch.

A method of controlling a battery system for preventing an abnormal voltage at an output stage, the method comprising:

• detecting, by a controller in a battery system, whether a voltage, which is a preset value or more, is applied from a battery cell through a voltage sensor;
• upon detecting that the voltage is the preset voltage value or more, providing, by the controller, a first control signal to a relay switch, which is connected externally to the battery system, to block a connection between the relay switch and the battery cell;
• in a state in which the connection between the relay switch and the battery cell is controlled to be blocked, detecting whether the voltage is applied from the battery cell through the voltage sensor;
• and
• upon detecting the voltage applied from the battery cell, outputting a second control signal for blocking a connection to an automatic cut-off switch of a battery management system (BMS) that is connected to the battery cell so as to cut off the voltage applied from the battery cell.