Abstract: A charging/discharging control device that can protect a chargeable/dischargeable battery cell from an excess current state while preventing the device from being increased in scale and from being complex. The charging/discharging control device includes: switches that are connected in parallel on current paths between a battery and a positive terminal of a battery pack; a switching control unit that switches between a charging current path and a discharging current path; a protective element that fuses the charging current path when a current value of the charging current path flowing through the switch exceeds a first fusing current value; and a protective element that fuses the discharging current path when a current value of the discharging current path flowing through the switch exceeds a second fusing current value higher than the first fusing current value.

Abstract: A protection element wherein variations in fusing characteristics are improved by making the amount of a flux applied on a fusible conductor uniform. The protection element includes: an insulating substrate; a heating element laminated on the insulating substrate and covered with an insulating member; first and second electrodes, formed at both ends of the insulating substrate; an internal heating-element electrode laminated on the insulating member so as to be superposed above the heating element; and a fusible conductor whose ends are connected to the first and second electrodes, and center portion of which is connected to the internal heating-element electrode. To both ends of the heating element, there are connected heating element electrodes to connect a power supply to generate heat by passing electric current through the heating element. In the fusible conductor, a depression portion opened upward is formed at a position to be superposed above the heating element.

Abstract: To provide a protection element evens the amount of flux on a fusible conductor and improves variations in fusing characteristics. A protection element is provided with: an insulated substrate; a heating body; an insulating member; two electrodes; a heating body internal electrode; a fusible conductor which is stacked over the two electrodes from the heating body internal electrode and fuses a current path between the two electrodes by heating; a flux coated on the fusible conductor so as to superimpose on the heating body; and a cover member attached to the insulated substrate covering at least the fusible conductor. The cover member has a cylindrical protrusion formed on an inner surface of the cover member so as to contact the flux, and a communication hole communicating with the inner surface side of the cover member from the protrusion is opened on a side wall surface of the cover member.

Abstract: To realize a protection member that makes a flux amount applied on a fusible conductor uniform, and improves variation of fusing characteristics. The protection member includes an insulating substrate, a heating body, an insulating member, two electrodes, a heating body internal electrode, a fusible conductor layered from the heating body internal electrode to the two electrodes, and configured to fuse a current path between the two electrodes by heating, flux applied on the fusible conductor to superimpose with the heating body, and a cover member covering at least the fusible conductor and attached to the insulating substrate. The cover member further includes a plurality of cylindrical projection portions facing the heating body and formed on an inner surface of the cover member to be in contact with the flux.

Abstract: A protective element including a substrate having a first insulating member and a concave portion formed thereon, a heating body layered on the concave portion of the substrate, a second insulating member layered on the substrate so as to cover at least covering the heating body, first and second electrodes layered on a surface of the substrate on which the second insulating member is layered, a heating body electrode layered on the second insulating member so as to be superimposed with the heating body, and electrically connected to a current path between the first and the second electrodes as well as onto and the heating body, and a low-melting point metal layered from the heating body electrode toward the first and the second electrodes configured to cause a blowout of the current path between the first and the second electrodes by heating.

Abstract: A charging/discharging control device that can protect a chargeable/dischargeable battery cell from an excess current state while preventing the device from being increased in scale and from being complex. The charging/discharging control device includes: switches that are connected in parallel on current paths between a battery and a positive terminal of a battery pack; a switching control unit that switches between a charging current path and a discharging current path; a protective element that fuses the charging current path when a current value of the charging current path flowing through the switch exceeds a first fusing current value; and a protective element that fuses the discharging current path when a current value of the discharging current path flowing through the switch exceeds a second fusing current value higher than the first fusing current value.

Abstract: A protective element is provided that is capable of stopping heat generation of a heat generation resistor after all of fuse elements are surely blown out in a case where the power is distributed from a specific power distribution path. The protective element can be configured to control blowout times of a plurality of respective fuse elements in such a manner that other fuse elements are blown out prior to the blowout of a specific fuse element in a case where the power is distributed from the specific power distribution path connected with the specific fuse element among the plurality of fuse elements.

Abstract: A protection circuit is provided, which protects a battery pack from overcurrents and overvoltages using sensing means and a protection device having a heating resistor and a fuse element provided on a circuit board. This protection circuit allows for sharing a protection device regardless of the current rating and the voltage rating of the battery pack, thereby being manufactured at low costs.

Abstract: A protective element has a heat-generating member and a low-melting metal member on a substrate, in which the low-melting metal member is blown out by the heat generated by the heat-generating member, wherein at least two strips of low-melting metal member are provided as the low-melting metal member, for example, between the pair of electrodes that pass current to the low-melting metal member, so that the lateral cross section of at least part of the low-melting metal member is substantially divided into at least two independent cross sections. This protective element has a shorter and more consistent operating time. It is preferable here to provide at least two strips of low-melting metal member between the pair of electrodes that pass current to the low-melting metal member. It is also preferable to provide one strip of low-melting metal member having a slit in its center, between the pair of electrodes that pass current to the low-melting metal member.

Abstract: A secondary battery device 1 including multiple protective circuits U1-U3 connected in parallel and each having two fuses fa, fb connected in series, wherein a terminal tc of each heater h is connected to a switch element 4 via rectifier element D1-D3. Even if a potential difference is generated between terminals tc, no residual current flows because any one of the rectifier elements D1-D3 is reverse-biased.

Abstract: A protective element with improved spherical segmentation performance during the melting of a low-melting metal member, has a heat-generating member and a low-melting metal member on a substrate, in which the low-melting metal member is heated and blown out by the heat generated by the heat-generating member. There is a region in which the low-melting metal member is suspended over the underlying base (such as an insulating layer), and when S (?m2) is the surface area of a lateral cross section of the low-melting metal member 4 between a pair of low-melting metal member electrodes 3a and 3b or 3b and 3c sandwiching the region, and H (?m) is the height at which the suspended region is suspended, then the relationship H/S?5×10?5 is satisfied. It is preferable here that the upper surfaces of both of the pair of low-melting metal member electrodes protrude beyond the upper surface of the underlying insulating layer.

Abstract: A protection circuit is provided. The protection circuit protects a battery pack from overcurrents and overvoltages using sensing means and a protection device having a heating resistor and a fuse element provided on a circuit board. This protection circuit allows for sharing a protection device regardless of the current rating and the voltage rating of the battery pack, thereby being manufactured at low costs. A protection circuit protects a battery pack having serially connected rechargeable batteries from overcurrents and overvoltages. The protection circuit includes a protection device having heating resistors and fuse elements provided on a circuit board, and sensing means for detecting an overvoltage across any of the batteries in the battery pack and switching a current flowing into the heating resistor. The protection circuit allows the sensing means in an overvoltage condition to switch on the current flowing through the heating resistor.

Abstract: Protective devices for preventing overcurrent and overvoltage are disclosed. The devices includes a base substrate, a pair of electrodes formed on the base substrate, and a low-melting metal element connected between the pair of electrodes to interrupt the current flowing between the electrodes by fusion. An insulating cover plate is positioned and fixed in contact with the pair of electrodes serving as a spacer member.

Abstract: A protective element has a heat-generating member and a low-melting metal member on a substrate, in which the low-melting metal member is blown out by the heat generated by the heat-generating member, wherein at least two strips of low-melting metal member are provided as the low-melting metal member, for example, between the pair of electrodes that pass current to the low-melting metal member, so that the lateral cross section of at least part of the low-melting metal member is substantially divided into at least two independent cross sections. This protective element has a shorter and more consistent operating time. It is preferable here to provide at least two strips of low-melting metal member between the pair of electrodes that pass current to the low-melting metal member. It is also preferable to provide one strip of low-melting metal member having a slit in its center, between the pair of electrodes that pass current to the low-melting metal member.

Abstract: A protective element with improved spherical segmentation performance during the melting of a low-melting metal member, has a heat-generating member and a low-melting metal member on a substrate, in which the low-melting metal member is heated and blown out by the heat generated by the heat-generating member. There is a region in which the low-melting metal member is suspended over the underlying base (such as an insulating layer), and when S (?m2) is the surface area of a lateral cross section of the low-melting metal member 4 between a pair of low-melting metal member electrodes 3a and 3b or 3b and 3c sandwiching the region, and H (?m) is the height at which the suspended region is suspended, then the relationship H/S?5×10?5 is satisfied. It is preferable here that the upper surfaces of both of the pair of low-melting metal member electrodes protrude beyond the upper surface of the underlying insulating layer.

Abstract: Protective devices for preventing overcurrent and overvoltage are disclosed. The devices includes a base substrate, a pair of electrodes formed on the base substrate, and a low-melting metal element connected between the pair of electrodes to interrupt the current flowing between the electrodes by fusion. An insulating cover plate is positioned and fixed in contact with the pair of electrodes serving as a spacer member.

Abstract: A secondary battery device 1 including multiple protective circuits U1-U3 connected in parallel and each having two fuses fa, fb connected in series, wherein a terminal tc of each heater h is connected to a switch element 4 via rectifier element D1-D3. Even if a potential difference is generated between terminals tc, no residual current flows because any one of the rectifier elements D1-D3 is reverse-biased.

Abstract: A protective element contains a heat-generating member and a low melting metal member on a substrate, in which the low melting metal member is molten by the heat generated by the heat-generating member and flows onto electrodes, which causes the low melting metal member to blow out, Formula (1) below is satisfied: (cross-sectional area of the low melting metal member)/(surface area of the blowout-effective electrode)≦0.15  (1) Alternatively, Formula (2) below is satisfied: 2.5≦(inter-electrode distance)/(cross-sectional area of the low melting metal member)≦30  (2) wheren the inter-electrode distance is defined as the distance between two electrodes, among the low melting metal member electrodes onto which the molten low melting metal member flows, which are adjacent to each other with the low melting metal member interposed therebetween.

Abstract: A protective element contains a heat-generating member and a low melting metal member on a substrate. The low melting metal member is caused to blow out by the heat generated by the heat-generating member. The number of locations on the low melting metal member which are able to blow out is larger than the number of locations which are supposed to blow out so that the protective element is endowed with a “fail-safe” function.

Abstract: A protective element contains a heat-generating member and a low melting metal member on a substrate, in which the low melting metal member is molten by the heat generated by the heat-generating member and flows onto electrodes, which causes the low melting metal member to blow out, Formula (1) below is satisfied: