Abstract: Disclosed is an electrochemical device including an electrode assembly having a cathode, anode and an electrolyte, and a casing surrounding the electrode assembly. The device further includes a protection device to which either or both of a cathode lead for connecting a cathode with an outer terminal and an anode lead for connecting an anode with an outer terminal are connected electrically, wherein the protection device is disposed in the inner space of the casing and the electrode lead equipped with the protection device is folded at both sides of the protection device so that the largest surface of the protection device is layered on a lateral surface of the casing where the electrode lead is present.

Abstract: A thermistor, which is to be mounted on a PCB, for protecting other circuit elements is disclosed. Electrode patterns separately formed on both surfaces of a film resistance element are respectively shaped into two parts which are engaged to each other with a non-conductive gap interposed therebetween. Thus, a Tombstone phenomenon caused by asymmetric structure may be fundamentally prevented. Grooves are formed in both sides of the thermistor, and connection portions for electrically connecting the electrodes formed on both surfaces of the thermistor are formed through the inside of the grooves or through the sides except the grooves. Thus, though a crack arises in the connection portion, it is possible to prevent the crack from being propagated to the entire connection portion along the side of the thermistor.

Abstract: A thermistor of which resistance is changed depending on temperature and a secondary battery to which the thermistor is attached are disclosed. The thermistor is attached to an object via a lead which is made of different kinds of materials. The lead is configured so that a part of the lead to be united to the thermistor electrode is mainly made of the same material as the electrode and a part of the lead to be united to the object is mainly made of the same material as the surface of the object. Thus, the thermistor may be simply attached to the object only using the ultrasonic welding, thereby remarkably reducing junction inferiorities.

Abstract: A thermistor, which is to be mounted on a PCB, for protecting other circuit elements is disclosed. Electrode patterns separately formed on both surfaces of a film resistance element are respectively shaped into two parts which are engaged to each other with a non-conductive gap interposed therebetween. Thus, a Tombstone phenomenon caused by asymmetric structure may be fundamentally prevented. Grooves are formed in both sides of the thermistor, and connection portions for electrically connecting the electrodes formed on both surfaces of the thermistor are formed through the inside of the grooves or through the sides except the grooves. Thus, though a crack arises in the connection portion, it is possible to prevent the crack from being propagated to the entire connection portion along the side of the thermistor.

Abstract: A thermistor is disclosed, which comprises a resistance element having upper and lower surfaces and showing a resistance varying characteristics according to the change of temperature; first and second conductive layers formed on the upper surface of the resistance element and engaged to each other with a non-conductive gap interposed therebetween; first and second electrodes formed on the lower surface of the resistance element and electrically separated from each other; a first connector for electrically connecting the first conductive layer to the first electrode; and a second connector for electrically connecting the second conductive layer to the second electrode. Thus, the thermistor has a structurally point-symmetric shape, so it is possible to prevent the Tombstone phenomenon, caused by an asymmetric structure.

Abstract: Disclosed is a PTC (Positive Temperature Coefficient) current limiting device for limiting a current by use of PTC characteristics, which includes a PTC element having the PTC characteristics; a pair of electrode units arranged on both sides to face each other with the PTC element being interposed therebetween; and a molding part prepared around the PTC element and the electrode units to surround at least an interface region between the PTC element and the electrode units, the molding part being made of elastic insulating material. The molding part is made of an elastic insulating material or any insulating materials selected from vacuum, gas and oil. Thus, this device may effectively restrain an arc generated while limiting overcurrent or short circuit current, and also prevent flashover between electrodes.

Abstract: Disclosed is a PTC (Positive Temperature Coefficient) current limiting device, which limits a current using PTC characteristics. The device includes a PTC element having the PTC characteristics; and upper and lower contact electrodes arranged to face each other with the PTC element being interposed therebetween, wherein, assuming that a distance from an end of the upper contact electrode to an end of the PTC element is a1, a distance from an end of the lower contact electrode to the end of the PTC element is a2, a thickness of the PTC element is b, and L=a1+a2+b, the following equations are satisfied: V/L<10 and V/b<50, where V is a rated voltage of the PTC current limiting device, a unit for a1, a2 and b is mm, and a unit for V is volt. This PTC current limiting device may prevent generation of flashover between electrodes.

Abstract: A thermistor of which resistance is changed depending on temperature and a secondary battery to which the thermistor is attached are disclosed. The thermistor is attached to an object via a lead which is made of different kinds of materials. The lead is configured so that a part of the lead to be united to the thermistor electrode is mainly made of the same material as the electrode and a part of the lead to be united to the object is mainly made of the same material as the surface of the object. Thus, the thermistor may be simply attached to the object only using the ultrasonic welding, thereby remarkably reducing junction inferiorities.

Abstract: Disclosed is a lithium secondary battery with high stability and excellent performance, and its manufacturing method. The lithium secondary battery includes a positive electrode including a positive electrode active material, a conductive material and a binding material and a negative electrode including a negative electrode active material and a binding material, and PTC powder is contained in at least one of the positive electrode and the negative electrode. If the battery is overheated due to overcharge, the PTC powder contained in the positive electrode and/or the negative electrode abruptly increases electric resistance to break electric current, thereby preventing further increase of temperature and resultantly preventing fire or explosion. In addition, the conductive material is contained separately from the PTC powder, performance of the battery is not deteriorated in the normal operation.

Abstract: A thermistor, which is to be mounted on a PCB, for protecting other circuit elements is disclosed. Electrode patterns separately formed on both surfaces of a film resistance element are respectively shaped into two parts which are engaged to each other with a non-conductive gap interposed therebetween. Thus, a Tombstone phenomenon caused by asymmetric structure may be fundamentally prevented. Grooves are formed in both sides of the thermistor, and connection portions for electrically connecting the electrodes formed on both surfaces of the thermistor are formed through the inside of the grooves or through the sides except the grooves. Thus, though a crack arises in the connection portion, it is possible to prevent the crack from being propagated to the entire connection portion along the side of the thermistor.

Abstract: A thermistor is disclosed, which comprises a resistance element having upper and lower surfaces and showing a resistance varying characteristics according to the change of temperature; first and second conductive layers formed on the upper surface of the resistance element and engaged to each other with a non-conductive gap interposed therebetween; first and second electrodes formed on the lower surface of the resistance element and electrically separated from each other; a first connector for electrically connecting the first conductive layer to the first electrode; and a second connector for electrically connecting the second conductive layer to the second electrode. Thus, the thermistor has a structurally point-symmetric shape, so it is possible to prevent the Tombstone phenomenon, caused by an asymmetric structure.