Relay driving circuit and battery system having the same

A battery system, comprising:

• a main relay configured to control an electrical connection between an external device and a battery pack;
• a pre-charge relay connected in parallel to the main relay and configured to be turned on before the main relay is turned on, and turned off after a predetermined time elapses after the main relay is turned on;
• a battery management system (BMS) that generates a control signal to control switching of the main relay and switching of the pre-charge relay;
• and
• a relay driving circuit including a first relay driving circuit controlling ON/OFF of the pre-charge relay, by including a transistor that receives a first control signal of an enable level from the BMS to perform an ON operation, a first resistor having a first end connected to a positive electrode of the battery pack and a second end connected to the pre-charge relay by the ON operation of the transistor, and a second resistor connected between the second end of the first resistor and the external device,
• wherein the pre-charge relay receives power supplied from the battery pack in a ratio of a resistance value of the second resistor to a sum resistance value of the first resistor and the second resistor to perform an ON operation.