Overcharge protection circuit secondary battery and method for protecting from overcharge using the same

摘要

The present invention relates to an overcharge prevention circuit capable of preventing an electric current in advance in a safe area of a cell, thereby improving safety. The secondary battery overcharge preventing circuit according to the present invention comprises: a PTC element provided in a charging circuit of a secondary battery; A heater for heating the PTC element; Sensing means for sensing a cell voltage of the secondary battery; And a driving circuit for measuring a voltage to be sensed and outputting a current for generating the heater when a voltage equal to or higher than a reference voltage is measured. When the heater, which generates heat by the current, heats the PTC element, The charging current of the charging circuit is cut off.