An apparatus for preventing over-discharge , comprising: a first switch (SW1) located on a first discharge path that electrically connects a battery cell (B) and an output terminal (Pack+, Pack-); a second switch (SW2) located on the first discharge path (L1) and having one end and the other end respectively electrically connected to the other end of the first switch and the output terminal; the apparatus being characterised by further comprising a current limiting resistor (Rptc) located on a second discharge path (L2) that electrically connects a first node (N1) located between the first switch (SW1) and the second switch (SW2) and a second node located between the second switch (SW2) and the output terminal, the current limiting resistor having one end electrically connected to the first node; a third switch (SW3) located on the second discharge path (L2) and having one end and the other end respectively electrically connected to the other end of the current limiting resistor and the second node (N2); and a processor configured to set a reference voltage by using a minimum operating voltage of the battery cell, a first drop voltage by the current limiting resistor (Rptc) and a second drop voltage by an internal resistor of the battery cell and control operation states of the first switch, the second switch and the third switch based on the reference voltage, wherein the processor is configured to calculate the first drop voltage by using a variable resistance of the current limiting resistor according to temperature and a discharge current of the battery cell, and the processor is configured to calculate the second drop voltage by using an internal resistance of the battery cell (B) according to temperature and a discharge current of the battery cell. a first switch (SW1) located on a first discharge path that electrically connects a battery cell (B) and an output terminal (Pack+, Pack-); a second switch (SW2) located on the first discharge path (L1) and having one end and the other end respectively electrically connected to the other end of the first switch and the output terminal; the apparatus being characterised by further comprising a current limiting resistor (Rptc) located on a second discharge path (L2) that electrically connects a first node (N1) located between the first switch (SW1) and the second switch (SW2) and a second node located between the second switch (SW2) and the output terminal, the current limiting resistor having one end electrically connected to the first node; a third switch (SW3) located on the second discharge path (L2) and having one end and the other end respectively electrically connected to the other end of the current limiting resistor and the second node (N2); and a processor configured to set a reference voltage by using a minimum operating voltage of the battery cell, a first drop voltage by the current limiting resistor (Rptc) and a second drop voltage by an internal resistor of the battery cell and control operation states of the first switch, the second switch and the third switch based on the reference voltage, wherein the processor is configured to calculate the first drop voltage by using a variable resistance of the current limiting resistor according to temperature and a discharge current of the battery cell, and the processor is configured to calculate the second drop voltage by using an internal resistance of the battery cell (B) according to temperature and a discharge current of the battery cell. <EOS>