Abstract: A composite board is fixed by solder to an electrode land formed on a circuit board having an electric wiring. The composite board and another metal plate are bonded by using an electric welding method or the like. By bonding a metal plate of a low resistance or a non-metal plate to the composite board, heat of high temperature or a large current which is generated upon electric wiring can be made difficult to be transferred to a lower portion of the composite board. A structure of a terminal member in which it is possible to prevent the solder under the composite board from being diffused, the solder is not scattered to the periphery, and a short-circuit is not caused is obtained. The terminal member to form the circuit board which is more mechanically and electrically stable is provided.

Abstract: A battery pack having a secondary battery is disclosed. The battery pack comprises at least one voltage converter; and switching means for switching an operation mode of the voltage converter to one of a charging mode and a discharging mode, in the charging mode, a charging voltage being output to the secondary battery, in the discharging mode, a voltage of the secondary battery being converted into a predetermined discharging voltage and the converted voltage being output.

Abstract: A protecting circuit monitors a voltage of a secondary battery and supplies the signal to permit a discharge to a gate terminal of a discharge control FET when the voltage is equal to or more than a lower limit value in a rated voltage range. When the discharge control FET receives this signal, it is connected and passes a discharge current. In the other cases, it shuts off the discharge current. Further, when the voltage is equal to or more than a predetermined value, a signal of a voltage of a battery voltage or more is supplied from a voltage converter to the gate terminal. When the voltage is equal to or less than an upper limit value in the rated voltage range, the protecting circuit supplies the signal to permit a charge to a gate terminal of a charge control FET. Further, when the voltage is equal to or more than a predetermined value, the voltage output from the voltage converter is supplied to the gate terminal.

Abstract: A composite board is fixed by solder to an electrode land formed on a circuit board having an electric wiring. The composite board and another metal plate are bonded by using an electric welding method or the like. By bonding a metal plate of a low resistance or a non-metal plate to the composite board, heat of high temperature or a large current which is generated upon electric wiring can be made difficult to be transferred to a lower portion of the composite board. A structure of a terminal member in which it is possible to prevent the solder under the composite board from being diffused, the solder is not scattered to the periphery, and a short-circuit is not caused is obtained. The terminal member to form the circuit board which is more mechanically and electrically stable is provided.

Abstract: A battery pack housing a plurality of battery cells in a case and respectively connecting the positive electrodes and the negative electrodes of the plurality of battery cells to conductive terminal boards to be led out to outside terminals is provided. The conductive terminal board has a structure in which a first member is joined with a second member such that the first member having excellent weldability is arrayed in a plurality-of-islands state in the second member having excellent conductivity, and the positive electrodes and the negative electrodes of the battery cell are welded to the first member of the conductive terminal board through resistance-welding, so that the battery pack capable of efficiently supplying a large amount of current is provided.

Abstract: In a battery pack including a plurality of secondary batteries within an outer case, any one of an adhesive, a gel filler, and a flat rubber sheet having a thermal conductivity of more than 0.4 W/mK (0.96×10−3 cal/cm·sec·° C.) is provided at a gap between the plurality of secondary batteries and the outer case.

Abstract: The battery pack according to the present invention is to avoid any trouble or the like of the primary or secondary battery inside the battery pack with a simple mechanical construction when a load is intermittently connected between the external terminals of the battery pack. For this end, the battery pack includes at least the battery cell and a protection circuit for shutting off overcurrent discharge and features in the provision of shut-off holding means and releasing means. The shut-off holding means maintains discharge shut-off condition after abnormal discharge shut-off by shorting or connecting a low resistance between the external plus terminal and the external minus terminal from outside of the battery pack. The releasing means releases the shut-off condition of the shut-off holding means when a predetermined voltage is applied between the external plus terminal and the external minus terminal.

Abstract: An electronic device protection circuit inhibits a voltage exceeding the rated voltage of the electronic device, which may include a secondary battery, from being applied and includes a positive temperature characteristic device and a diode that are connected in series and arranged in proximity to each other. The thermal fuse, the posistor, and the zener diode are arranged to conduct heat to each other, so that applying an overvoltage greater than the rated voltage to input terminals of the electronic device causes the current resulting from the overvoltage to flow through the zener diode that causes it to generate heat that accelerates the fusion of the thermal fuse.

Abstract: A metal plate and an electrode in a polymer lithium ion secondary battery or the like are welded certainly, and it is accomplished to further improve the reliability and the durability thereof. Each of an upper metal plate (7a) and a lower metal plate (9a) on the positive pole/terminal is welded to a pole/terminal of positive electrode (3) so that the pole/terminal of positive electrode (3) may be sandwiched from each of the upper and lower sides. Moreover, each of an upper metal plate (7b) and a lower metal plate (9b) on the negative pole/terminal is welded to a pole/terminal of negative electrode (5) so that the pole/terminal of negative electrode (5) may be sandwiched from each of the upper and lower sides. This eliminates occurrence of poor welding in the electric resistance welding.

Abstract: The present invention enables to mount a primary cell to increase the battery capacity and to charge a secondary cell while the primary cell is mounted. A select switch selects a first selectable terminal or a second selectable terminal having a higher voltage applied. A control circuit selects a secondary cell or a primary cell which can output a higher voltage and outputs voltage from that cell.

Abstract: When any one or ones of at least two cells connected in parallel together is judged to be faulty by a cell failure detector, it is electrically disconnected to the normal other cells. Alternatively, when any one or ones of at least two cells connected in series together is judged to be faulty by a controller, a cell current interrupter is shifted from a connected position to a disconnected position connected in series to the faulty cell to interrupt a current line while a cell short-circuit device connected in parallel to the faulty cell by the cell current interrupter is shifted from a disconnected position to a connected position, thereby shorting a circuit portion corresponding to the faulty cell.

Abstract: When any one or ones of at least two cells connected in parallel together is judged to be faulty by a cell failure detector, it is electrically disconnected to the normal other cells. Alternatively, when any one or ones of at least two cells connected in series together is judged to be faulty by a controller, a cell current interrupter is shifted from a connected position to a disconnected position connected in series to the faulty cell to interrupt a current line while a cell short-circuit device connected in parallel to the faulty cell by the cell current interrupter is shifted from a disconnected position to a connected position, thereby shorting a circuit portion corresponding to the faulty cell.

Abstract: The present invention is to provide an electronic device protection circuit which can reliably inhibit a wide range of overvoltage from being applied to a secondary battery, a semiconductor device or any other electronic device, and can protect the protection circuit itself from being degraded or damaged. Further, the electronic device protection circuit of which circuit configuration is extremely simple is provided. The electronic device protection circuit which inhibits a voltage exceeding the rated voltage of the electronic device from being applied thereto, comprises a positive temperature characteristic device and a diode which are connected in series and arranged in close proximity to each other thereon. As a result, the electronic device protection circuit can protect the electronic devices such as a secondary battery protection IC from being damaged or degraded.

Abstract: In a battery cell or a battery pack, employing the battery cell, it is necessary to stop the malfunction of the battery cell or the battery pack due to leakage of an electrolyte solution from progressing to prevent occurrence of an accident such as ignition or fuming. To this end, a battery pack includes a battery cell 3, a leakage detection unit 4 for detecting the leakage of an electrolyte solution of the battery cell 3, a current breaker 5 for electrically interrupting a current line between the battery cell and external terminals 9 on occurrence of leakage of the electrolyte solution in the battery cell 3, and a discharging device 6 having the function of self-discharging the battery cell 3. The battery pack is connected to a main equipment body unit X or to a charger Y to effect discharging or charging, respectively.

Abstract: A water-insoluble hydrophilic polymer composition capable of crosslinking at ambient temperature. The composition contains (A) a water-insoluble hydrophilic copolymer prepared by copolymerizing (a) at least one carboxyl group containing ethylenically unsaturated monomer selected from acrylic acid, methacrylic acid, maleic anhydride, fumaric acid, itaconic acid and citraconic acid, (b) at least one amino group containing ethylenically unsaturated monomer of the formula: ##STR1## where R.sub.1 -R.sub.4 are specifically defined, and (c) an ethylenically unsaturated monomer selected from (i) a monomer of the formula: ##STR2## (R.sub.6 being alkyl), (II) A MONOMER OF THE FORMULA: ##STR3## and (iii) diacetone acrylamide, and (B) a polyepoxide crosslinking agent having at least two terminal epoxy groups. The water absorption rate of the polymer can be adjusted over a wide range and has sufficient coating strength and bonding strength to withstand long periods of immersion in water.