Abstract: A method for displaying a charge level of a battery includes the steps of (1) displaying the charge level of the battery in a first manner during battery charging, and (2) displaying the charge level of the battery in a second manner which is different than the first manner during battery discharging. The first manner displaying step includes the step of operating a battery charge level indicator in a first mode, and the second manner displaying step includes the step of operating the battery charge level indicator in a second mode which is different than the first mode. In addition, a battery charge level indicator is disclosed and includes a display for indicating a charge level of a battery, and a mechanism for operating the display so as to indicate whether the battery is in a charge state of operation or a discharge state of operation.

Abstract: A secondary battery charging circuit of this invention includes a charging source for supplying a charging current to a secondary battery, a temperature detection unit for generating an output which changes almost linearly with respect to a change in temperature of the secondary battery during a charging operation, a differential unit for obtaining a differential value of an output from the temperature detection unit, a comparator unit for comparing the differential value during the charging operation with a setting value, and for, when the relationship between the two values is reversed, generating an inverted output, a timer circuit unit, started simultaneously with start of the charging operation of the secondary battery, for generating a timer output after an elapse of a predetermined period of time, and a charge control unit for controlling the charging operation of the secondary battery in response to one, generated earlier, of the inverted output from the comparator unit, and the timer output from the

Abstract: In a battery housing and charging system for a range of cordless tools, a universal charger accepts battery packs of several configurations and size (number of cells). The common feature of the battery packs is (at least) one cell housed on end and substantially coaxial with a specific terminal block assembly. Terminal pins are shielded from external contact and engage the charger terminals in a recessed well in the floor of the charger receptacle. Charger terminals are at one end of the receptacle which is elongated so that it can accommodate a battery pack "nose" portion with either one or two cells housed on end and side-by-side. Upright side walls of the receptacle provide stabilizing support for the battery pack In the battery pack portion outside the receptacle, cells may be arranged in any configuration to suit tool or other requirements. Charger output terminals are normally biased away from their respective terminal apertures to minimize risk of accidental contact with live terminals.

Abstract: A power converter that can be used either as a start converter or as a variabe speed constant frequency converter is utilized within a stepped waveform VSCF system having engine start capability. Interfacing with the converter are a load bus, a contactor, a field excitation controller and a starter/generator having a main generator, an exciter generator and a permanent magnet generator. Magnetic components and semiconductor components perform multi-functions and minimal degradation of input power quality occurs.

Abstract: An engine-driven generator includes an internal combustion engine, a permanent magnet alternator and an AC to AC converter. The output frequency and voltage of the permanent magnet alternator are largely dependent on engine speed and the alternator load. The AC to AC converter converts the speed-dependent alternating current developed by the alternator to another alternating current whose frequency and voltage are largely independent of engine speed. Voltage regulation is provided by varying the engine speed in accordance with the load current. Frequency regulation is provided by frequency dividing the alternator output by an integer divisor that varies in accordance with engine speed. Additional voltage regulation is provided by deleting selected cycles of the alternator output current as needed to maintain the RMS output voltage within predetermined limits.

Abstract: In a voltage regulator for an alternator which charges a battery via a charging cable and supplies a vehicle mains with voltage, the output voltage is regulated as a function of the temperature of the battery. The voltage regulator has a power part and a control part, which includes a simulation device for storing data and for determining the temperature of the battery, and hence the optimum charging voltage, by simulation from the stored data. Further, the voltage drop between the alternator and battery can be calculated from the alternator current and the resistance of the charging cable while taking into account correction factors which take into account the different connections of the consuming devices between the alternator and the battery so that the calculated voltage drop and the optimum charging voltage for the battery can be used by the voltage regulator to set the voltage delivered to the battery.

Abstract: An electrochemical charge-storage system for defibrillator energy delivery where a plurality of switched battery cells with high energy storage capacity are incorporated for delivering an electrical charge within an implanted defibrillator system. Alternative embodiments include circuitry for battery replacement switching of a faulty battery.

Abstract: A charging system monitors the rate of change in battery voltage, adjusts the rate of charging, and checks the changes in battery voltage following adjustments in the rate of charging to observe a predetermined sequence of voltage changes that signifies when a battery is fully charged. The charging system determines the slope between consecutive battery voltage measurements. The charging system charges a battery at the full battery capacity in response to positive or zero voltage slope measurements and reduces the charging rate in response to negative voltage slope measurements. A nickel-cadmium battery is fully charged when at least one sequence of a negative slope, followed by a decrease in charging rate, then a positive or flat slope, followed by an increase in charge rate, and finally another negative slope is observed.

Abstract: A fuse system for a battery charger provides fuse links for safely charging a plurality of batteries in parallel connection. A fuse system is used with a power supply comprising a positive and a negative terminal. The positive and negative terminals of the power supply are connected respectively to separate positive and negative bus bars of the fuse system. A plurality of connectors separately connect the positive bus bar to the positive terminals on the batteries and separately connect the negative bus bar to the negative terminals on the batteries. Each connector includes a fuse link. The fuse link comprises a plurality of fusible conductors connected in parallel. A transparent cover over the fuse link protects the operator and enables the visual inspection of the condition of the fuse link.

Abstract: A universal charger adapted for rechargeable battery packs of various size is equipped with a battery pack mounting seat having a stop flange disposed at one side thereof which is inserted in a receiving cavity of the charger case. The neighboring side of the stop flange of the mounting seat is provided with a guide track onto which is disposed an adjustment slide member having a mono-track projection disposed thereon and being able to be vertically adjusted so that a pair of sliding terminal seats each equipped with a horizontal and a vertical probe pin can be horizontally adjusted to vary the positions thereof along with the vertical adjustment of the slide member in conformance to battery of different size and structure.

Abstract: A battery discharging apparatus is provided with a battery discharger and a control unit. The control unit is provided with a current sensor and a battery power capacity sensor. The control unit directs the discharger to recover battery capacity lost due to memory effect using a deep memory effect eliminating discharge.

Abstract: A power resource management system includes a battery charging system (20) that is connected between a positive voltage terminal and a voltage sense terminal (15). An operating system (10), that in one mode operates off of the battery and in a second and charging mode operates off the power source (24), is connected between the positive terminal (12) and the voltage sense node (15). A sense resistor (16) is connected between the voltage sense node (15) and a ground terminal (18). The power source (24) is operable to deliver voltage across the positive terminal (12) and the negative terminal (18). The battery charger (20) includes a charge modulator (24) and a buck regulator which has a switch (26) that is controlled by the controller (34).

Abstract: A battery charging device uses a primary battery source which is preferably a rechargeable lead acid battery, connected to a secondary battery source, which is preferably a pair of parallel battery circuits each using series-connected non-rechargeable batteries in series with a diode, the primary and secondary battery sources providing a charging voltage output. A switch has a first position in which the charging voltage output can be supplied to an external battery which is to be charged and a second position in which a recharging voltage can be supplied from an external source to recharge the primary battery source, and a third, or off, position in which charging and recharging operations cannot occur.

Abstract: An output current of an alternator and a load current are detected by current sensors 5 and 6. When the output current of the alternator has a predetermined value or lower, generation of electricity by the alternator is stopped. When the load current has a predetermined value or higher, generation of electricity is resumed. When the load current is increased, a load-responsive control for the alternator and an intake air increasing control is performed, and the generation of electricity of the alternator is stopped at an acceleration time of the engine, and the output of the alternator is gradually increased.

Abstract: An electric system for an electric vehicle includes a main battery used for driving the vehicle, an auxiliary battery used for accessories of the vehicle, an AC motor for driving one or more wheels, an inverter for converting DC power supplied from the main battery to AC power to be supplied to the AC motor, and an auxiliary battery charging circuit for charging the auxiliary battery by using the AC power from the inverter. When charging the auxiliary battery, the AC power is insulatedly transformed and then rectified. In another example, an input capacitor in the inverter is charged by a DC-DC converter connected with the auxiliary battery as its power supply when the inverter starts. The system enables the auxiliary battery charging circuit to be small, light and low cost. The system can also charge the auxiliary battery for accessories even when the vehicle is stopping.

Abstract: A battery-power portable apparatus includes a first constant current source supplies a low current to a battery when the battery voltage is initially lower than a reference level, and when the reference level is reached a second constant current source takes over to supply a high charging current. The battery voltage is constantly monitored to detect a peak voltage and a subsequent voltage drop. When the battery voltage drops a predetermined amount from the peak voltage, the second constant current source is disabled, and the first constant current source is rendered active to charge the battery with a low current on an intermittent mode.

Abstract: A battery monitoring method and apparatus are used for monitoring the charge level of a rechargeable electric storage battery, for example a lead acid battery. The counter-voltage of the battery is monitored by continuously monitoring the actual terminal voltage of the battery. When the battery is fully charged, the monitor provides a "DO NOT CHARGE" signal, for example a green light. When the charge level has dropped to a point that there may be some value in recharging the battery, the "DO NOT CHARGE" signal is replaced with an "OK TO CHARGE" signal, for example a yellow light. When the battery has discharged to the point where the battery must be recharged in order to avoid damage, the "OK TO CHARGE" signal is replaced with a "MUST CHARGE" signal, for example a red light. Audible signals may accompany the "OK TO CHARGE" and "MUST CHARGE" signals. The monitor is self-testing when turned on. It automatically recognizes the charge level of a battery to which it is connected.

Abstract: An electronic device for effectively preventing time-varying current from passing through an electro-chemical cell or battery is disclosed. Time-varying current flowing in a circuit which includes the cell/battery is sensed externally to the cell/battery with a magnetically-coupled ac current probe thereby producing an induced time-varying signal. This induced signal is amplified to the level of the original time-varying current and applied to the cell/battery's terminals in phase-opposition to the original current. As a result, the component of time-varying current flowing in the cell/battery's external leads assumes an alternate path around the cell/battery and is effectively canceled within the cell/battery itself. Time-varying voltage across the cell/battery, which would normally result from time-varying current passing through its internal impedance, is likewise eliminated.

Abstract: A cordless telephone system in which a battery of a mobile unit can be charged with use of a cordless charger. The charger, which is provided separately from a base unit, has a chargeable battery which is larger in current capacity than the battery within the mobile unit. When the mobile unit is mounted on the charger, the battery of the mobile unit is charged with the battery of the charger. So long as the charge level of the battery within the charger is sufficiently high, the battery of the mobile unit is charged with the battery of the charger and without use of a commercial AC power source.

Abstract: A storage battery is first substantially fully discharged before it is charged. A load impedance is first connected across the battery to receive current from the battery and develop a signal representative of the state of charge of the battery. Sensing this signal provides an indication of when the battery becomes substantially fully discharged. The load impedance is then disconnected, and the battery then receives charging current. A full-wave rectifier couples the battery to an LED that may be coupled to the battery to provide the indication of when the battery becomes substantially fully discharged. This indication may be used to operate relays to disconnect the load impedance from across the battery and charge the battery.