A protective element includes a fuse element, a movable member, a concave member, and a press. The fuse member includes, a first end, a second end, and a cut part positioned between the first end and the second end. The fuse element is energized in a first direction from the first end to the second end. The movable member and the concave member are disposed facing each other such that the cut part is interposed therebetween. The press applies a force to the movable member in a pressing direction in which a distance between the movable member and the concave member shortens. At a temperature at or above a softening temperature of the fuse element, the cut part is cut by the force of the press.

Problem To maintain a low internal resistance value and adjust spring characteristics by using a movable contact made of a multilayered material.

Means for Solving Problem A thermosensitive pellet-type thermal fuse includes, in an interior of a cylindrical case having electrical conductivity, a thermosensitive pellet that melts or softens at a temperature, a strong compression spring configured to press the thermosensitive pellet, an insulating cover closing the cylindrical case, a weak compression spring abutting against the insulating cover, a first lead extending through the insulating cover and including an inner end as a fixed contact, a movable contact electrically connecting to the first lead and the cylindrical case, a sealing resin provided surrounding a portion of the first lead and covering an outer end portion of the insulating cover, and sealing an open end portion of the cylindrical case, and a second lead disposed at one end of the cylindrical case. The movable contact includes a conductive base material and a conductive member covering a predetermined surface of the conductive base material. The conductive member is provided to contact portions with the fixed contact and an inner wall surface of the cylindrical case, and is made of a material having a Young’s modulus and a rigidity different from those of the conductive base material.

The present disclosure provides a high-temperature thermal pellet composition that maintains structural rigidity up to a transition temperature of about 240° C. The composition comprises at least one organic compound (e.g., triptycene or 1-aminoanthroquinone). The pellet can be disposed in a housing of a thermally-actuated, current cutoff device, such as a high-temperature thermal cutoff device (HTTCO). Also provided are material systems, which include the pellet composition and a high-temperature seal that provides substantial sealing up to at least the transition temperature. Methods of making such high-temperature pellet compositions and incorporating them into a thermally-actuated, current cutoff device are also provided.

A fuse element includes: a low-melting-point metal layer; a high-melting-point metal layer provided over at least one surface of the low-melting-point metal layer; and an intermediate layer disposed between the low-melting-point metal layer and the high-melting-point metal layer. Each of the high-melting-point metal layer and the intermediate layer is made of a metal that is liquefied by contacting a molten form of the low-melting-point metal layer. The high-melting point metal layer is made of silver or an alloy comprising silver as a main component thereof. A melting point of a material constituting the intermediate layer is higher than a melting point of a material constituting the low-melting-point metal layer and lower than a melting point of a material constituting the high-melting-point metal layer.

An apparatus for modifying an electrical circuit includes a first electrical contact, a second electrical contact, an electrical coupler formed of an electrically conductive material, a first assembly including a cavity, a driving portion, an inhibiting portion, and a second assembly electrically coupled to the second electrical contact. The electrical coupler is moveable within the cavity along a movement axis, a wall of the cavity is electrically coupled to the first electrical contact and to the electrical coupler, and when the electrical coupler is disposed at an initial position within the cavity, the electrical coupler is not electrically coupled to the second electrical contact. The driving portion applies a first force on the electrical coupler in a movement direction along the movement axis. The inhibiting portion inhibits the movement of the electrical coupler along the movement axis.

A protective element includes: at least two electrode portions (main electrodes) supported by an insulating support (insulating substrate); a fuse element that connects the electrode portions; and an operating flux provided on the fuse element. The operating flux has, on a surface thereof, a coating layer that covers the operating flux to prevent the operating flux from flowing.

An apparatus for modifying an electrical circuit includes a first electrical contact, a second electrical contact, an electrical coupler formed of an electrically conductive material, a first assembly including a cavity, a driving portion, an inhibiting portion, and a second assembly electrically coupled to the second electrical contact. The electrical coupler is moveable within the cavity along a movement axis, a wall of the cavity is electrically coupled to the first electrical contact and to the electrical coupler, and when the electrical coupler is disposed at an initial position within the cavity, the electrical coupler is not electrically coupled to the second electrical contact. The driving portion applies a first force on the electrical coupler in a movement direction along the movement axis. The inhibiting portion inhibits the movement of the electrical coupler along the movement axis.

A battery control apparatus for a battery according to the present invention excludes a faulty battery cell from the connection between battery cells and at the same time automatically connects a replacement battery cell to the battery cells when a fault occurs in some of the battery cells, thereby allowing the output voltage of the battery to be kept constant in spite of the faulty battery cell. Further, in a state where a plurality of battery modules are connected in parallel, the battery control apparatus disconnects a battery module including a faulty battery cell during the replacement of the faulty battery cell, thereby preventing the output voltage of the battery from being discontinuous. In addition, a switch used in the battery control apparatus for a battery is a fusible switch including two separate fixed electrodes and one movable electrode.

The temperature sensitive pellet type thermal fuse includes a cylindrical case which has a first end and a second end, a temperature sensitive pellet, an insulating tube, a first lead which is inserted into the insulating tube and has an inner end serving as a contact portion, a movable contact which is electrically connected to the cylindrical case, a weak compression spring, a strong compression spring, and a second lead which is disposed on the second end of the cylindrical case. The movable contact includes a projecting contact portion which is provided at a central part of the movable contact, and the projecting contact portion and the contact portion of the first lead are in contact with each other inside the insulating tube.

The temperature sensitive pellet type thermal fuse includes a cylindrical case which has a first end and a second end, a temperature sensitive pellet, an insulating tube, a first lead which is inserted into the insulating tube and has an inner end serving as a contact portion, a movable contact which is electrically connected to the cylindrical case, a weak compression spring, a strong compression spring, and a second lead which is disposed on the second end of the cylindrical case. The movable contact includes a projecting contact portion which is provided at a central part of the movable contact, and the projecting contact portion and the contact portion of the first lead are in contact with each other inside the insulating tube.