PROTECTION DEVICE AGAINST OVERCHARGE CONTAINING PHASE CHANGE MATERIAL AND SECONDARY BATTERY EMPLOYED WITH THE SAME

摘要

PURPOSE: A protection device for a secondary battery is provided to prevent the overcharging as electrons are conducted by reducing resistance values by phase change materials in a specific voltage or more and to improve the safety of the secondary battery. CONSTITUTION: A protection device(100) suppresses the overcharging of a secondary battery since a positive electrode(101) and a negative electrode(102) are parallel-connected on a circuit. The protection device includes a first resistance(110) which is connected to a positive electrode of the secondary battery and distributes the voltage applied to the second resistance; a second resistance(120) which is connected to the first resistance and lowers the resistance value caused by phase transfer in a temperature rise; and a third resistance(130) which is connected to the second resistance and the negative electrode of the secondary battery.