Abstract: A voltage measurement circuit includes a plurality of voltage input terminals that are supplied with voltage outputted by secondary batteries via voltage measurement lines, a plurality of voltage sensors connected between each of the plurality of voltage input terminals; and a plurality of constant current sources that are connected between the plurality of the voltage input terminals and supply the plurality of voltage input terminals being connected with specified voltage when the voltage measurement line is disconnected.

Abstract: Systems and methods for regulating pre-charge current in a battery system, such as a battery system of an information handling system, by controlling duty cycle of the charging current provided to battery cell/s of the battery system.

Abstract: A system is provided for balancing state of charge among plural series connected electrical energy storage units that includes a power converter that selectively couples to an individual storage unit of the a string of electrical energy storage units and bidirectionally transfers energy between the individual storage unit and the string of storage units.

Abstract: A power generating system includes a power generator generating DC power, and an inverter circuit for converting DC power into AC power. The power generator has a plurality of power generating modules each including a plurality of power generating units and at least one electric storage device connected to each of the plurality of power generating modules. A plurality of first switch devices connect/disconnect each of positive electrodes of the plurality of power generating modules to/from a positive bus, a plurality of second switch devices connect/disconnect each of the positive electrodes of the plurality of power generating modules to/from negative electrodes of the power generating modules which are contiguous to one side, a plurality of third switch devices connect/disconnect each of the negative electrodes to/from a negative bus, and the DC output voltage can be increased/decreased stepwise by switching the switch devices.

Abstract: A battery backup system includes a control device including a power sensing device, a discharge circuit, a charging circuit, and a plurality of battery packs. A lower threshold is established representative of a minimum acceptable effective energy capacity. Each battery pack is recharged if its effective energy capacity falls below the lower threshold. Additionally, an upper threshold is established representative of the minimum acceptable effective energy capacity plus a performance margin. In a two battery-pack system, if both battery packs fall below the upper threshold, the battery with the least effective energy capacity is discharged to the minimum acceptable effective energy capacity and then recharged to the battery pack's maximum energy capacity. In this way, both battery packs are prevented from approaching the minimum acceptable effective energy capacity at the same time. This reduces the size or number of battery packs and reduces their associated cost and volume.

Abstract: A NiH/NiCd (nickel hydrogen/nickel cadmium) battery charger with the function of emergency power supply unit having a main body with a charging chamber and a charging circuit positioned within the main body to allow an electric connection to the charging chamber and the power input interface. This charging control circuit is controlled by an electrical switch which divides the charging chamber into two or more parts. When the power input interface is connected, the electrical switch shuts off automatically to make the batteries in the charging chamber to be charged in groups. This is the function of charger. When the power input interface is switched off, the batteries in different circuit are joined in series to supply power as an emergency power supply unit. Therefore, with the design principle of “separate charging and common sharing”, it can protect the rechargeable batteries and provide power in lacking of power supply unit outdoors.

Abstract: When a control section (39) turns on a switch (31, 33, 35), a capacitor (37) is connected to a secondary battery (B1) in parallel. Accordingly, voltage between both ends of each capacitor (37, 38) reaches voltage between both polarities of each secondary battery (B1, B2). Thereafter, when the control section (39) turns off the switch (31, 33, 35) and turns on a switch (32, 34, 36), each capacitor (37, 38) is connected to the secondary battery (B2, B3) in parallel. The capacitor (37, 38) is charged/discharged to balance voltage between both polarities of the secondary battery (B1 to B3).

Abstract: A method and circuit for energizing an electric energy storage device (10) to a high voltage with electric energy supplied by a high voltage electric power source (16) in a safe, effective and efficient manner by first moving electric charges supplied by a high voltage power source (16) to a capacitive device (20) and then subsequently transferring the electric charges stored in an energized capacitive device (20) to an electric energy storage device (10) for later use. A method and circuit for de-energizing an electric energy storage device (10) from a very high voltage in a safe, effective, and efficient manner by first moving electric charges supplied by the electric energy storage device to a capacitive device (20) and then subsequently de-energizing an energized capacitive device (20) through an electrical load device (18) so that useful work can be performed.

Abstract: A voltage measurement device includes a first group of switches Q1, Q2, a second group of switches Q7, Q8 and a third groups of switches Q5, Q6. By turning on the third group of switches Q5, Q6, the first group of switches Q1, Q2 are turned on, so that a condenser C1 is charged by voltage impressed between a voltage input terminal A and a voltage input terminal B. While the first group of switches Q1, Q2 are turned off by tuning off the third group of switches Q5, Q6, the second group of switches Q7, Q8 are turned on, so that voltage retained in the condenser C1 is generated between a voltage output terminal G and a voltage output terminal H.

Abstract: A battery energy balance circuit and a battery charging bypass circuit is disclosed for batteries being charged at the same time to be charged equally. When the terminal voltages of the batteries are different, a controllable power device switch in the circuit switches on and off at a high frequency in order to reduce the input current to the batteries with higher terminal voltages and to increase the input current to the batteries with lower terminal voltages, achieving the goal of equal charging. The disclosed energy balance circuit can avoid damages to the batteries as a result of overcharging. When the number of batteries increases, one can expand the system in a modularized way to prevent inconvenience of circuit designs.

Abstract: A capacitor charging circuit and method including a plurality of serially connected capacitors and parallel monitor circuits connected in parallel on a one-to-one basis to the capacitors. Each one of parallel monitor circuits applies a direct-current source voltage to a capacitor and bypasses a charge current of the capacitor when the charge voltage of the capacitor exceeds a reference voltage. Each of the parallel monitor circuits includes a reference voltage circuit, a voltage detecting circuit, a comparator, a bypass switching circuit, and a voltage limiter. The reference voltage circuit generates the reference voltage. The voltage detecting circuit detects the charge voltage of the capacitor. The comparator compares the reference voltage with an output voltage from the voltage detecting circuit and controls the bypass switching circuit to bypass the charge voltage using the voltage limiter to limit a voltage applied to the bypass switching circuit.

Abstract: A device for a battery charger, includes connection elements 14, 16 connected to the output lines of the charger, connection elements 16, 24 for connection to the terminals of a battery to be charged. The device includes elements 80 for detecting a voltage over the output lines of the charger, elements 80 for detecting a positive voltage over the terminals of a connected battery, switch elements 60 for connecting at least one of the output lines to the connection elements to the terminals of the battery, and a switch activating element 70 arranged to the voltage detection elements and designed and arranged such that it is capable of activating the switch when a voltage is detected over the output lines of the charger and a positive voltage is detected over the terminals of the connected battery, thereby connecting the charger to the battery.

Abstract: A power generating system is described including a plurality of electrochemical cells. The cells are generally arranged in sections that are selectively activated individually or in combination to produce power from selected cell sections. A method of generating power is also described. A first group of one or more electrochemical cells of an array of cells are selectively activated based on requirement of an associated load. The system switches to a second group of one or more electrochemical cells of the array when the first group is discharged.

Abstract: A bandgap reference circuit and method of using the same are provided. The bandgap reference circuit may provide start-up requirements at substantially any voltage and at substantially any temperature. The circuit comprises an op amp (two stages of transistors) and a network of resistors and bipolar diodes. When an artificial offset of about ?5 mV is introduced to the op amp, the op amp output will be high as soon as the power supply exceeds the transistors' threshold voltages. The op amp output supplies the resistor and diode network and brings the op amp inputs within desired regulation voltages.

Abstract: A battery charger includes line-level input rectification, a high-frequency oscillator-controlled chopper circuit, multiple transformers operating in parallel, and controlled output rectification. Use of line-level input rectification reorders the elements of the battery charger compared to previous designs. A chopper frequency several orders of magnitude higher than that of the AC power mains is used. The use of multiple, parallel-wired transformers for voltage and current transformation eases constraints on the physical geometry of a manufactured battery charger product by permitting individual transformers, each smaller than a comparable single transformer, to be employed. Controlled output rectifiers permit power levels to be regulated dynamically.

Abstract: A system and method for battery isolation in a charging system includes an isolation diode connected to a charger input voltage and a PNP pass transistor connected in series between the isolation diode and a battery. The pass device conducts a charging current in response to a drive signal applied to its base; the pass transistor side of the diode is at a voltage Vchg. A first switch couples the pass transistor's base to Vchg when Vchg>Vbat such that the pass transistor's base-collector junction blocks current from Vchg from flowing through the pass transistor when the charger is not in use, and a second switch couples the base to Vbat when Vbat>Vchg such that the pass transistor's base-emitter junction blocks current from the battery from flowing through the pass transistor when the charger is not in use.

Abstract: A battery charger method and apparatus are disclosed for providing detailed battery status and charging method information for a selected one of multiple batteries that are simultaneously coupled to the battery charger. The battery charger includes a controller. The controller selects one of the batteries to monitor and charge. The controller then starts a measurement cycle for the selected battery. During the measurement cycle, the controller determines current battery characteristics of the selected battery. The controller determines whether the selected battery is ready for charging by determining whether the battery characteristics of the selected battery are within a specified range. If the controller determines that the selected battery is ready for charging, the controller causes the battery charger to start charging the battery. If the controller determines that the selected battery is not ready for charging, the controller selects another battery to monitor and charge.

Abstract: A battery current limiter and current-limiting method for a battery system and an electric motor in a hybrid automotive vehicle powertrain. The battery current limiter monitors measured battery current and torque commands. A modified current is developed to take a predetermined current margin into account. The modified current reduces battery current in a closed loop fashion simultaneously with a reduction in commanded torque by a feed-forward torque value.

Abstract: A power generating system is described including a plurality of electrochemical cells. The cells are generally arranged in sections that are selectively activated individually or in combination to produce power from selected cell sections. A method of generating power is also described. A first group of one or more electrochemical cells of an array of cells are selectively activated based on requirement of an associated load. The system switches to a second group of one or more electrochemical cells of the array when the first group is discharged.

Abstract: A dual voltage motor drive is disclosed. In an exemplary embodiment, the motor includes a rotor assembly, rotatingly disposed within a stator assembly, and a plurality of motor phase windings configured to be energized in a determined sequence to cause a rotation of the rotor assembly. The plurality of motor phase windings are divided into a first group of windings selectively energized by a first voltage source, and a second group of windings selectively energized by a second voltage source, wherein the motor remains operational in the event of a failure of one of the first and second voltage sources.

Abstract: When an electronic timepiece is in a power-saving mode in which the current time display is suspended, it is determined whether or not the charge voltage supplied from a high-capacity capacitor is higher than a predetermined reference voltage, and if higher, enough electrical energy is stored in the high-capacity capacitor to return from the power-saving mode to the display mode, so that a current time restoration process is performed upon detecting power generation. On the other hand, if the charge voltage is less than or equal to the predetermined reference voltage, the supply of the power supply voltage to the control circuits is stopped to prevent the electrical energy stored in the high-capacity capacitor from being consumed needlessly. As a result, the electronic timepiece can be reactivated quickly when the power generating device begins to generate power.

Abstract: A fuel cell system is protected by monitoring at least one fuel cell parameter, comparing the parameter to a preset level, and disconnecting or reconnecting a main load in response to the fuel cell parameter. For example, a fuel cell system (300) is provided with a protection circuit (304, 308) that prevents operation of the fuel cells in the negative dP/dI region. System (300) includes a stack of fuel cells (302) connected in series and coupled to a main load (310). A controller (304) provides a control signal (314) based on the individual fuel cell voltage levels falling above or below a preset level. Control signal (314)is used to control a load switch (308)coupled between the stack of fuel cells (302) and the main load (310). The load switch (308) disconnects the main load (310) in order to prevent operation of the fuel cell cells in the negative dP/dI region.

Abstract: The battery charging process monitors the battery charging pockets waiting for an indication that a battery or a phone-battery combination has been inserted into their respective pockets. The first battery that is inserted is the high priority battery and is charged first while any subsequent battery inserted into a charging pocket has no power applied until the high priority battery is charged. If the phone enters a call while in the charger, it becomes the high priority battery if it was not already. In this case, power is removed from the individual battery and applied to the phone-battery combination until the call has been completed. At this point, the process returns the high priority status to the battery that had it prior to the call interrupt.

Abstract: An apparatus and method for controllably charging and discharging individual battery cells or groups of battery cells in a string of batteries employed as a back-up power supply is provided. The apparatus includes battery supply modules for at least partially isolating battery strings from the load bus and primary power supply. The partial isolation is effected by a switching network including two controlled switches arranged in parallel to selectively isolate the string of batteries. In certain disclosed embodiments, one of the controlled switches is turned on to connect the string of batteries to the load bus until the other controlled switch closes. The system includes a main power supply that supplies a power bus to a regulator in each battery supply module, which is used for charging the battery string, and a discharge bus to each battery supply module for discharging the batteries.

Abstract: The invention provides a charging rate adjusting circuit 2 which comprises a serial line 21 for connecting a plurality of cell blocks 11, 12, a switch 22 interposed on the line 21, a plurality of parallel lines 23 for connecting a plurality of parallel connecting points each corresponding to in the cell blocks 11, 12, switches 24 each interposed on each of the lines 23, discharge circuits 28 connected to a opposite electrodes of each of the cell modules, a voltage measuring circuit 26 for detecting voltage across each of the cell modules, and a control circuit. The control circuit, in usual operation, sets on the switch 22 and sets off all the switches 24, while, in adjustment, the circuit sets off the switch 22 and sets on all the switches 24, and sets on the discharge operation of the circuit 28 based on detection result of the circuit 26.

Abstract: A controller controls a switch bank which can shunt a voltage source in parallel with one or more fuel cells in a stack. By controlling the voltage of the voltage source, the current through the fuel cells is directly controlled. By increasing the anode potential of the fuel cell through control of the voltage source, poisons deposited on the electrocatalyst are removed, thereby rejuvenating the fuel cells. Fuel cells in a stack can be treated in turn, causing a reduction of the effects of electrocatalyst poison on stack performance.

Abstract: An improved rechargeable battery which comprises: a plurality of battery cells connected together to discharge in parallel, each of the cells, or each group or groups of the cells having its own respective recharging input; and an electrical switching circuit to switch a number of the battery cells or groups of cells to connect to their respective recharging input for recharging each cell or group of cells individually.

Abstract: A power generating system is described including a plurality of electrochemical cells. The cells are generally arranged in sections that are selectively activated individually or in combination to produce power from selected cell sections. A method of generating power is also described. A first group of one or more electrochemical cells of an array of cells are selectively activated based on requirement of an associated load. The system switches to a second group of one or more electrochemical cells of the array when the first group is discharged.

Abstract: A data terminal apparatus includes a basic unit, a plurality of units, a power supply circuit, switching units and a controller. The basic unit realizes a basic function of the data terminal apparatus and requires a basic quantity of DC power. Each of the plurality of units realizes a specific function of the data terminal apparatus and requires quantities of DC power. The power supply circuit receives DC power from a power supply source, and can supply the DC power to the basic unit and the plurality of units. The switching units are provided for the plurality of units, and each of the switching units selectively supplies the DC power from the power supply circuit to a corresponding one of the plurality of units in response to a switching control signal. The controller selectively outputs the switching control signals to the switching units based on the DC power of the power supply source.

Abstract: A generation control device of a hybrid electric vehicle is able to satisfactorily generate power with an excellent responsiveness with respect to a high output requirement from a motor. If a charge level SOC sensed by a charge level sensing device is not greater than a generation start value SOCsta, a generator starts a normal output generation (P(G)=P1). The normal output generation is continued until the charge level SOC reaches a generation end value SOCend larger than the generation start value SOCsta. If a required power consumption Pm of a traction motor sensed by a required power consumption sensing device is not less than Ph, a high output generation (P(G)=P2) with a higher output than the normal output generation is executed instead of the normal output generation.

Abstract: A battery backup system has a number of batteries and number of switches interconnecting the batteries to either a high-power load or a low-power load. The batteries are selectively connected in series with each other, or in parallel with each other by the switches. When the batteries are in the parallel configuration they are also connected to power the low-power load, and when in series, to power the high-power load. Between switching from the high-power series configuration to the low-power parallel configuration, a transition phase is provided during which a transition battery powers the low-power load.

Abstract: A controller controls a switch bank which can shunt a voltage source in parallel with each fuel cell in a stack. By controlling the voltage of the voltage source, the current through the fuel cell is directly controlled. By increasing the anode potential of the fuel cell through control of the voltage source, poisons deposited on the electrocatalyst are removed, thereby rejuvenating the fuel cell. Each fuel cell in a stack can be treated in turn, causing a reduction of the effects of electrocatalyst poison on stack performance.

Abstract: A cell voltage balancer for balancing the voltage of the first cell and the voltage of the second cell. The cell voltage balancer includes the first input terminal, the second input terminal and the third input terminal. The cell voltage balancer includes a transformer, the first switch and the second switch. The transformer includes a primary winding and a secondary winding. The first switch and the primary winding are serially connected between the first input terminal and the second input terminal. The second switch and the secondary winding are serially connected between the second input terminal and the third input terminal. The first switch and the second switch are switched on and off alternatively. While the first switch is on and the second switch is off, the primary winding stores energy of the first cell in the transformer. On the contrary, the secondary winding recovers energy stored in the transformer into the second cell.

Abstract: A controller controls a switch bank which can shunt a voltage source in parallel with each fuel cell in a stack. By controlling the voltage of the voltage source, the current through the fuel cell is directly controlled. By increasing the anode potential of the fuel cell through control of the voltage source, poisons deposited on the electrocatalyst are removed, thereby rejuvenating the fuel cell. Each fuel cell in a stack can be treated in turn, causing a reduction of the effects of electrocatalyst poison on stack performance.

Abstract: The present invention relates to a charging device for storing electric energy in a plurality of electrical double layer capacitors, comprising a power source circuit, a capacitor bank having a plurality of capacitors, a control circuit for switching an interconnection state of the plurality of capacitors, and a voltage monitor circuit for monitoring a charged voltage in the plurality of capacitors, which repetitively carries out a step of performing a charging operation by switching the plurality of capacitors in the capacitor bank to a serial connection state, and a step of monitoring a charged voltage by using a voltage monitor circuit by switching the plurality of capacitors to a parallel connection state until the charged voltage reaches a predetermined value.

Abstract: Deficiencies in the electrolyte level of the cells of NiCd battery can be detected by measuring the internal resistance of the cells. Initially, data is collected for a battery type and capacity, correlating measured internal resistance with the amount of water that must be added to bring the cell resistance to an acceptable value. Subsequently, cells of other batteries of the same type and capacity can be measured to determine how much water must be added and the levels quickly restored. The polarization value of the cells can be used lieu of the internal resistance in the same fashion.

Abstract: The invention relates to a device for managing battery packs by measuring and monitoring the operating capacity of individual battery modules in a battery pack. A programmable logic controller directs the selective closing of relays to allow individual battery modules to be load-tested using a variable discharge load unit, without compromising useful battery pack capacity. A battery module whose useful capacity falls below a predefined threshold may be connected to a battery charger for replenishment and then electrically realigned with the remaining modules in the pack for continued operation. Alternatively, an alarm may be triggered which alerts the user that the module is due for replacement. This sequence of events is performed on all cells in the pack at a predetermined interval.

Abstract: Almost no consideration has heretofore been given to power saving of an uninterruptible power supply apparatus (UPS) and to power saving of a total system including power saving of the load apparatus connected to the UPS and the devices attached to the load apparatus thus wasting electric power and indicating need for improvement.

Abstract: The present invention provides a cost-effective, accurate use of multiple batteries in a battery pack 110. The battery pack 110 consisting a plurality of battery cells 112. A monitoring circuit 117, 217, 317 is provided that monitors the battery cells 112. The monitoring circuit 117, 217, 317 is connected to a microprocessor 119 through an analog-to-digital converter 114. The microprocessor 119 determines the amount of voltage remaining in the battery cells 112. The microprocessor 119 also monitors the voltage output from the battery pack 110. When the voltage being supplied by the battery pack 110 falls below a threshold value, a switching circuit 121, 221, 321 switches depleted battery cells 112 with charged battery cells 112.

Abstract: Described is a battery switching circuit in which a first battery and a second battery are connected to a common feeding point via a first feeding circuit and a second feeding circuit each including a semiconductor switch. The switch is alternately turned on so that one of the first and second batteries supplies electric power to the feeding point at a time. The battery switching circuit includes a first temperature sensor disposed in the proximity of the switch. A temperature detector is connected to the temperature sensor for generating an operational output in response to the output of the temperature sensor when the temperature of the switch exceeds a predetermined temperature. Lastly, a circuit is connected to the switch and is responsive to the operational output of the temperature detector for turning off the switch disposed in the proximity of the temperature sensor. Because the switch is protected from being overheated, it can be mounted on a low cost nonmetallic substrate.

Abstract: A protection circuit is used for a battery unit which has a plurality of cell parts coupled in parallel, and first and second power supplying terminals, where each of the cell parts includes a plurality of battery cells coupled in series, and first and second terminals respectively coupled to the first and second power supplying terminals. The protection circuit includes a plurality of switching elements making an electrical connection to the first terminal of a corresponding one of the cell parts and the first power supplying terminal, and disconnecting the electrical connection in response to an active signal, and a voltage monitoring circuit outputting the active signal to the switching elements when a voltage of at least one battery cell within one cell part falls outside a predetermined range, independently with respect to each of the cell parts.

Abstract: The invention encompasses a circuit that is capable of driving a load with the current as electrons flow during equilibration from a high-potential battery bank to a low-potential bank. The cells comprising each battery bank can be switched from being in parallel to each other to being in series; this switch causes the potential of each battery bank to change and thereby creates a relative potential difference between the cells. By switching the battery banks so that one bank is parallel and the other is serial, allowing the battery banks to equilibrate, and then switching the cells in the battery banks after equilibration from parallel to serial and serial to parallel, a potential difference can be recreated repeatedly and current flow maintained.

Abstract: An automatic battery power switch circuit which switches from n to n+m cells, where n and m are integers, in a battery. The circuit delivers a relatively constant voltage over a wide range of load current conditions. One embodiment switches based on load current. Another embodiment switches based on the output voltage of the circuit. The circuit provides a high speed automatic switch used in devices that require at least two power states, that can function as a voltage regulator, and that can significantly prolong functional battery life.

Abstract: In a power supply apparatus including a plurality of batteries and a plurality of power supply portions for connecting to loads, a plurality of switches connect these batteries to these power supply portions, respectively. The apparatus further includes a control mechanism which controls the opening and closing operations of the switches. When one of the switches is turned on in one of the power supply means, the control mechanism executes the control in such a manner that the other switches are turned off. The control mechanism further controls each of the switches on the basis of the remaining capacity of each battery and the load state of each power supply portion. Accordingly, the power supply operation can be flexibly carried out.

Abstract: In an electric motor vehicle, a bidirectional boosting converter is placed in a battery circuit. A main contactor is turned off to disconnect one battery block from another and contactors are turned on to connect a first battery block to one terminal pair of the bidirectional boosting converter and to connect a second battery block to another terminal pair of the bidirectional boosting converter. A refreshing discharge of the first battery block or an equalizing charge of the second battery block is performed by boosting output of the first battery block and using this output to charge the second battery block. The boosting direction of the bidirectional boosting converter is changed to perform an equalizing charge of the first battery block or a refreshing discharge of the second battery block. The boosting direction is changed again to balance battery block SOCs, these by eliminating need for a charging device for equalizing charge or a discharging device for refreshing discharge.

Abstract: When the cell of a battery, most notably a lithium ion battery, fails and human intervention is unavailable to correct the problem. a system is provided for optimizing the energy storage capacity of the battery. At least two cellular strings, each including a plurality of battery cells, are connected electrically in series. All cellular strings contain the same number of battery cells and are electrically connected in parallel to form a battery array powering a load. A sensor detects the condition of each battery cell and sends a signal of the detected condition to a controller for operating the battery array for powering the load. A switching arrangement is responsive to the sensor, upon failure of a battery cell in one cellular string, for disconnecting at least one other battery cell of the battery array such that, thereafter, the modified battery array continues to power the load with reduced but optimized capacity.

Abstract: An apparatus for controllably charging and discharging individual battery cells or groups of battery cells in a string of batteries employed as a back-up power supply is provided. The apparatus comprises an isolation circuit for at least partially isolating the battery string from the load bus and primary supply; a switching network including at least two controlled switches arranged to selectively form circuits for discharging one or more cells; and a logic circuit for selecting which of the cells will be discharged. In certain disclosed embodiments, the logic circuit and switching network combine to apportion charging current to individual battery cells or groups of cells in accordance with their charging needs.

Abstract: A dual smart battery mutual detection system that utilizes intelligence built in to "smart batteries" in combination with a battery presence pin for enabling each battery of a dual battery power supply system of a PC to detect the presence, or, more importantly, the absence, of the other battery and to react accordingly is disclosed. In one embodiment, upon detection by the battery that is not being used to power the PC (the "inactive battery") of the removal of the battery that is being used to power the PC (the "active battery"), a microprocessor internal to the inactive battery closes an internal switch thereof, thereby causing the previously inactive battery to be "selected" and used to power the PC.

Abstract: A system and method for increasing the available energy and system runtime of battery powered electric devices which use non-rechargeable cells as an energy source. The present invention employs techniques for using energy from both rechargeable and non-rechargeable batteries in a manner which discharges each of the different cells within their optimal discharge rate. In particular, the non-rechargeable batteries are used for a low rate of system discharge and rechargeable cells supplement the non-rechargeable batteries for a higher system loads. In a preferred embodiment of the present invention, when the system load is at a very low level, the rechargeable battery is recharged using power from the non-rechargeable battery. The result of the techniques of the present invention is the lowering of discharge rate and hence increasing the capacity of the non-rechargeable cell.

Abstract: Batteries in a battery string are provided with shunt circuits that shunt current about a battery when it is charged to an upper charge limit or discharged to a lower charge limit. The shunt circuits include an inductor and a switching network.