Abstract: The present invention provides an apparatus for controlling a capacitor charging circuit and a method thereof. The apparatus includes a first comparator, a second comparator, and a controller. The first comparator, which is coupled to the charging circuit, receives a voltage level and compares the voltage level with a reference voltage level to generate a first indication signal. The voltage level corresponds to an output voltage of the charging circuit. The second comparator receives a control value and compares the control value with a threshold value to generate a second indication signal. The controller, which is coupled to the charging circuit, the first comparator and the second comparator, generates a control signal according to the first indication signal and the second indication signal to turn the charging circuit on and off, and further generates the control value according to the control signal.

Abstract: A power supply circuit charging a secondary battery by a DC-DC converter using a switching element and an inductance element includes a current adjustment circuit. The current adjustment circuit adjusts a charging current of the secondary battery by turning on/off the switching element according to a voltage difference of a lower one of a reference voltage and a first control voltage corresponding to a temperature of the secondary battery from a current detection voltage corresponding to the charging current of the secondary battery.

Abstract: In the present invention, a battery pack type discriminating or deciding concave portion (131) is formed at a position corresponding to a battery pack type deciding switch (214) of an SQ battery pack (1) and when the SQ battery pack (1) is set, the battery pack type deciding switch (214) is avoided to be pressed by a bottom (115) of the SQ battery pack (1) owing to the concave portion (131). In this way, as the switch (214) is avoided to be pressed, it is recognized that the set battery pack is an SQ battery pack (1) under charging. Therefore, according to the present invention, it is possible to identify battery packs among different charging modes and charging can be performed in a proper charging mode.

Abstract: To prevent a battery pack from being over-discharged even under a state that the battery pack (a secondary battery) is connected to a discharging device that is not connected to an ac input power source for a long time. A charging device 200 has a pair of output lines L1 and L2 and an anode terminal O1 and a cathode terminal O2 of a secondary battery 2 electrically connected between the output lines L1 and L2 to carry out a charging operation. In the charging device 200 including a component circuit part (a resistance 33, a series connecting circuit of resistances 102, 103 and 105, a series connecting circuit of resistances 91 and 92 and an inner circuit part of a shunt regulator 116) electrically connected by traversing a part between the pair of output lines L1 and L2, a switching element 121 is inserted between the component circuit part (the resistance 33 or the like) and one of the pair of output lines L1 and L2.

Abstract: An energy saving type feeder voltage compensation apparatus improved in availability at low temperatures, wherein when a secondary battery is lower in temperature than a predetermined value, an output voltage output to a feeder side is made equal to or higher than a no-load output voltage of a substation connected in parallel. Power is supplied to a power running rolling stock preferentially from the secondary battery. The heating value of the secondary battery is increased and the battery temperature is raised by this discharging, whereby internal resistance of the secondary battery is lowered, and the charging and discharging loss is suppressed, and the efficiency and availability of the energy saving type feeder voltage compensation apparatus as a whole are improved.

Abstract: A battery protection device protects a battery from an abnormal state. The battery protection device includes a detector that detects an abnormality of the battery and outputs an abnormality detection signal when the abnormality is detected. A current is input to an input terminal from outside. A voltage converter converts the current input to the input terminal to voltage and outputs the voltage. A combiner combines the abnormality detection signal with the voltage and outputs a combined signal. A current converter converts the combined signal to a current. An output terminal outputs the current.

Abstract: Exemplary methods and systems for charging a battery in a power management unit include a power regulator having an input power supply and a processor that regulates a charging rate of the battery based on measured parameters of the power regulator and the battery. The processor is programmed to perform exemplary methods that include receiving an output voltage signal and a battery temperature signal from the power regulator, and comparing the output voltage to a first threshold to determine a charge level of the battery. An exemplary method includes selecting a charging mode based on the comparison, and sending a first control signal to the power regulator to adjust a charging rate of the battery based on the battery temperature.

Abstract: A method of changing a secondary battery, a method of calculating a remaining capacity rate of the secondary battery, and a battery pack are provided. The method of charging a secondary battery includes the steps of: performing a detection of a charging rate of the secondary battery using an integrating method in which a battery capacity is calculated by integrating a current value or a power value of the secondary battery for a certain period of time, and a detection of the charging rate of the secondary battery using a voltage method in which a voltage value of the secondary battery is measured and the charging rate is calculated based on a correlation between the voltage value and the charging rate; and performing a weighted addition of the charging rate detected by the integrating method and the charging rate detected by the voltage method in accordance with the charging rate of the secondary battery, whereby detecting a final charging rate.

Abstract: A method and apparatus for controlling the charge and discharge currents in a battery (2) as a function of temperature. When a battery (2) is charged or discharged in an environment that approaches its design operating temperature extreme, the currents are reduced to limit self-heating of the battery and thus extend the useful operating environment temperature range. A temperature sensor (18) is coupled to a controller (6) to sense the battery (2) temperature. The temperature information is used to set a suitable charging or discharging current (8). In the illustrative embodiment, the charging current is set to a maximum value when said temperature is lower than a first predetermined threshold value, the maximum value being the battery's maximum specified charging current, and the first predetermined threshold value being the battery's maximum charging temperature.

Abstract: In a portable power source system comprising a battery pack for accommodating at least one secondary battery and a mounting part for mounting the battery pack, the mounting part is disposed in power using equipment, the battery pack comprises a charge circuit having a charge terminal and a discharge circuit having a discharge terminal, the charge circuit comprises a control circuit for controlling a voltage and a current during charging, the mounting part comprises a protruding external terminal for connecting with the discharge terminal, the battery pack comprises an inserting part for inserting the external terminal, the discharge terminal is disposed in a concealed position inside the inserting part, the battery pack is movable from an initial position to a fixing position while the external terminal has been inserted in the inserting part, and connection between the external terminal and the discharge terminal is achieved at the fixing position.

Abstract: A method for training a support vector machine to determine a present state of charge of an electrochemical cell system includes choosing a training data, preprocessing the training data, finding an optimal parameter of the support vector machine, and determining support vectors.

Abstract: A fuel cell system determines each of a battery charging current error, a battery voltage error, and a stack current error. The fuel cell system regulates current through a series pass element in response to a greater of the determined errors. Thus, the fuel cell system operates in three modes: battery voltage limiting mode, stack current limiting mode and battery charging current limiting mode. Additionally, there can be a fourth “saturation” mode where the stack voltage VS drops below the battery voltage VB as the load pulls even more current. Individual fuel cell systems can be combined in series and/or parallel to produce a combined fuel cell system having a desired output voltage and current.

Abstract: A system (200) includes a battery charger (278) and a battery (202). The battery (202) includes a thermistor (230), a voltage identifying element (240), a switch (244), a memory device (232), and a battery data contact (228), connected to a data port of the memory device (232) and the voltage identifying element (240). The voltage identifying element (240) determines a voltage that controls the switch (244). When the switch (244) is enabled, the thermistor (230), connected to a battery clock contact (224), is active and a microprocessor (102) on the battery charger (278) reads the value of the thermistor (230) via an analog-to-digital converter. When the switch (244) is disabled, the thermistor (230) is switched out and the battery clock contact (224) is used to clock the memory device (232). The battery charger (278) has a data contact (226) for receiving the battery data contact (228) and a clock contact (222) for receiving the battery clock contact (224).

Abstract: Battery pack (10) may include rechargeable battery cells (12). Battery charger (20) may include power source circuit (100). Power source circuit (100) may be connected with an external power source and battery cells (12). The external power source may supply power to the power source circuit and then, the power source circuit may supply charging current to battery cells (12). Battery charger (20) may also include voltage detector (32, 33) for detecting the voltage input from the external power source to power source circuit (100). Battery charger (10) may further include processor (40) for controlling power source circuit (32). Processor (40) may determine the amount of charging current supplied to battery cells (12) based upon the external power source voltage detected by the voltage detector (32, 33).

Abstract: A control apparatus for controlling a regenerative operation of a vehicle motor includes a vehicle motor as a drive source of a vehicle, an energy storage device, including plural cells, for storing regenerative energy generated by a regenerative operation of the vehicle motor, and a total voltage measuring device for measuring a total voltage that is a sum of inter-terminal voltages of the plural cells, a cell voltage judgment device for determining whether the inter-terminal voltage of any one of the plural cells exceeds a predetermined regeneration limitation voltage, a total voltage estimating device for determining, when it is determined by the cell voltage judgment device that the inter-terminal voltage of any one of the cells exceeds the predetermined regeneration limitation voltage, an estimated total voltage which is defined as a total voltage at a time when the inter-terminal voltage of the one of the cells reaches a regeneration prohibition voltage that is higher than the predetermined regenerative

Abstract: In the case of charging by a charging apparatus having a plurality of input terminals to which external power sources for charging a secondary battery are inputted, it is prevented that a current of the inputted power source is outputted to the outside from the other input terminals for charging which are not used. If there are inputs from a plurality of input terminals, the input power sources are controlled so that the battery is optimally charged. pnp-type transistors Q1 and Q2 are arranged between two input terminals of a terminal 11 for an external power adaptor and a terminal 12 for a holder and a secondary battery E1, respectively. When a control IC 13 detects an input power voltage of one of the transistors, the transistor on the detected side is turned on. If the control IC 13 detects both input power voltages, a priority is allocated under predetermined conditions and the secondary battery E1 is charged by the power source of the higher priority.

Abstract: An electronic apparatus capable of effectively using power of an AC/DC adaptor including a host and an AC/DC adaptor is provided. The AC/DC adaptor is used for receiving an AC power and converting it into a DC power for the host. At the same time, the AC/DC adaptor outputs a controlling signal to control the power consumption of the host according to the power output at that time. The AC/DC adaptor includes a switching power converter for converting the AC power into the DC power, and a power supply controller for outputting a controlling signal according to the power output by the switching power converter.

Abstract: A charger includes a choke coil and a choke iron core disposed on a plane surface of heat dissipating fins. Furthermore, a face plate, a control circuit board, a drive circuit board, the heat dissipating fins, a fan and a ventilation plate are separately series-connected in alignment and fitted on a base thereof. The electric power from a power supply input is transmitted to the drive circuit board through an input terminal, whereupon alternating current passes through a rectifier circuit and is converted into direct current thereat. Upon charging, results from a detector are transmitted to a microprocessor, which effectuates switch over to an output circuit through transistors, while diodes prevent current reflux. The electric power is then transmitted to a battery by means of a transformer coupled to an electric power terminal and further passing through one more rectifier circuit and a wave filter circuit.

Abstract: A device for charging a battery comprises an alternating current source, a rectifier being connected with its input to the alternating current source and being connected with its output to the battery for charging thereof. It also has a member for measuring the charging current from the rectifier to the battery and a means (13) for comparing the measured charging current with a current limit value and an arrangement adapted to control the voltage on the output of the rectifier based on information about said comparison and decrease it if the measured current exceeds the current limit value for reduction of the charging current.

Abstract: A method of charging a battery from a power source is provided. The method includes providing a charge circuit in series with the battery and the power source. A charging current flowing to the battery and a voltage across the charge circuit are sensed. The power dissipated in the charge circuit is computed based on the charging current and the voltage across the charge circuit. During a first operating mode, the charging current is controlled so that the power dissipated in the charge circuit is about a predetermined maximum dissipation. During a second operating mode, the charging current is limited to a predetermined current level. During a third operating mode, the charging current is controlled so that the battery voltage is about a predetermined voltage level.

Abstract: When starting charging of an internal battery as a result of connection of an external power source by an AC adapter, a charging control unit sets a first charging voltage at which the charging capacity of the internal battery is maximized. When starting the charging from recognition of reduced capacity of the internal battery due to its self-discharge in desk-top use where the AC adapter is in connection at all times, the charging control unit sets a second charging voltage lower than the first charging voltage to prevent the battery from degrading.

Abstract: A motor drive 50 of an induction motor IM includes an inverter section 20, a charger 60, a charging and discharging circuit 70 and a control section 80. The charger 60 is for storing regenerated electric power of the induction motor via the inverter section. The charging and discharging circuit 70 is for making the charger charge electric power and making the charger discharge the electric power. The control section carries out control of the charging and discharging circuit for making the charger charge the electric power when the induction motor generates regenerated electric power and making the charger supply the electric power to the induction motor in accelerating the induction motor or in electricity interruption.

Abstract: A power supply for providing full time electrical power to a customer premises telecommunications hub. The supply includes an AC to DC power converter for converting power from the AC power grid to a DC voltage selected to maintain a backup battery at float voltage. The converter includes a first rectifier section for generating an unregulated DC voltage. This voltage is switched through the primary of an isolation transformer by a pulse width modulated voltage controller. The output of the transformer is connected to a second rectifier circuit and filter to produce a regulated DC output voltage. The regulated voltage is connected to a voltage correction circuit through a divider including a temperature compensator so that the feedback to the voltage controller causes the regulated output voltage to follow the battery float voltage at all temperatures. The unregulated DC voltage is coupled to the voltage controller current limiting input to protect the power supply at high input voltages.

Abstract: A method for monitoring the operational reliability of rechargeable lithium cells including measuring the cell voltage and cell temperature, the cell is discharged if a predetermined cell limit voltage (UG) and a predetermined ambient limit temperature TG are exceeded at the same time, until a predetermined lower voltage level or a predetermined lower ambient temperature is reached. A circuit for carrying out the method has a first threshold value switch which responds when a predetermined upper limit voltage (UG) is exceeded in the cell, and a second threshold value switch (C) which responds when a predetermined ambient temperature limit (TG) is exceeded, and has a logic circuit (E) which connects (G) the cell to a load when the first and second threshold value switches respond at the same time, wherein both threshold value switches (C, D) are configured such that they trip when a lower cell voltage or a lower ambient temperature is reached.

Abstract: A circuit of multiple units of step differential DC source to detect charging current and terminal voltage of a storage/discharging device, or to detect charging temperature so to control operation of control switches respectively connected in series with each unit of the DC source to change charging voltage or charging current to the storage/discharging device; or by means of a central control unit or a manual operation interface to set up the automatic cutoff time to change its charging voltage when preset time is up so to adjust and control its charging current or cutoff current.

Abstract: A vehicle electrical system is disclosed having a plurality of electrical subsystems for supplying power to different component groups of the vehicle. A voltage regulator is provided each subsystem for setting the voltage on each electrical subsystem independently of the other electrical subsystems. One such subsystem includes a battery having a grounded terminal and an ungrounded terminal. An electrical system controller including data processing capacity provides control of the voltage level on the charging subsystem through a charging regulator having an output connected to the ungrounded terminal of the battery and a control input. An electrical power generator is connected to energize the charging regulator. Instrumentation connected to the electrical system controller provides measurements of current discharged from the battery, current delivered to the battery, and battery temperature.

Abstract: A device and method of input/output control capable of exhibiting the battery performance by nature by rapidly raising the temperature of the secondary battery by the regeneration at a low temperature. A temperature rise controller controls the temperature rise of the battery pack based on the battery temperature, thereby determining a central value of the state-of-charge control in the range of the state of charge. A battery input/output controller voluntarily controls the state of charge based on the central value of the state-of-charge control from the temperature rise controller and the state of charge at the point of time from the state-of-charge operator, and controls charge and discharge based on the charge and discharge request from the outside to the battery pack.

Abstract: An uniterruptible power supply (UPS) system that includes one or more NiMH or Li-ion batteries is provided. In one general aspect, the invention features a power supply system including a power input to receive input power from a power source, a power output to provide output power to a load, at least one NiMH or Li-ion battery having a battery output that provides battery power, at least one power module coupled to the power input to receive the input power, coupled to the battery output to receive the battery power and coupled to the power output to provide the output power, a controller, coupled to the at least one power module, constructed and arranged to monitor and control the output power from the at least one power module. A UPS system using a NiMH or Li-ion battery typically uses less space and weigh less than a UPS having a lead acid battery. Additionally, NiMH and Li-ion batteries perform better at temperature extremes than do comparable lead acid batteries.

Abstract: Charging device 10 charges nickel-hydrogen batteries 58, while adjusting the current value so that the temperature follows the target temperature rise pattern. Therefore, nickel-hydrogen batteries that demonstrate a large temperature increase can be charged within a short time so that a high temperature is not attained. Furthermore, when lithium ion batteries 58 are charged, the current value is controlled so that the voltage follows the target voltage rise pattern. Therefore, lithium ion batteries can be charged at a potential no higher than the preset level.

Abstract: In a method for monitoring the charging of gastight alkaline rechargeable batteries, the characteristics of the critical charging voltage (Ucrit) on a rechargeable battery are determined as a function of the charging current (I) for various temperatures (T) and are linearized by means of a function in the form A(I)×T+B(I). The value pairs A and B are stored as parameter arrays in a battery management system, and during operation of a physically identical rechargeable battery which is to be monitored, the associated critical charging voltage is calculated by measuring the temperature and charging current and is used to control the charging of the rechargeable battery. On reaching the critical charging voltage (Ucrit) which corresponds to the critical state of charge (LZcrit), the value of the critical state of charge can be calculated by measuring the current (I) and temperature (T).

Abstract: A method of charging a battery in which the end of charging is determined by detecting variations in the battery temperature includes the following steps: entering a charging mode, periodically measuring the battery temperature, measuring the variation in the battery temperature per unit time, comparing the battery temperature variation per unit time to a first threshold corresponding to variation of the ambient temperature and the battery temperature, and in this case terminating the charging mode, and to variation of only the ambient temperature, and in this case comparing the battery temperature variation per unit time to a second threshold corresponding to variation of only the battery temperature and terminating the charging mode.

Abstract: A charging method of a rechargeable battery includes steps of: charging the rechargeable battery with a constant current; charging the rechargeable battery with a constant voltage or with a current having a pulse waveform; and when a charging current is decreased so as to be equal to or lower than a predetermined current value, or when an average charging current for a single pulse of the current having a pulse waveform is decreased so as to be equal to or lower than a predetermined current value, determining that the rechargeable battery has been fully charged and stopping the charging of the rechargeable battery, wherein a temperature of the rechargeable battery is measured, and the predetermined current value at which the charging of the rechargeable battery is stopped is adjusted according to the measured temperature.

Abstract: A battery charging apparatus comprising a controller to control on-off controllable switch elements of an AC power source output short circuit and including a first control section to control the on-off controllable switch elements so that they are at an on-state when an instantaneous terminal voltage of a battery exceeds a first set value and a second control section to control the on-off switch elements so that they are at an on-state when an average voltage of the battery exceeds a second set value and serving to control them when a power source switch is closed.

Abstract: In a method for monitoring the charging of gastight alkaline rechargeable batteries, the characteristics of the critical charging voltage (Ucrit) on a rechargeable battery are determined as a function of the charging current (I) for various temperatures (T) and are linearized by means of a function in the form A(I)×T+B(I). The value pairs A and B are stored as parameter arrays in a battery management system, and during operation of a physically identical rechargeable battery which is to be monitored, the associated critical charging voltage is calculated by measuring the temperature and charging current and is used to control the charging of the rechargeable battery. On reaching the critical charging voltage (Ucrit) which corresponds to the critical state of charge (LZcrit), the value of the critical state of charge can be calculated by measuring the current (I) and temperature (T).

Abstract: A device and method of input/output control capable of exhibiting the battery performance by nature by rapidly raising the temperature of the secondary battery by the regeneration at a low temperature. A temperature rise controller controls the temperature rise of the battery pack based on the battery temperature, thereby determining a central value of the state-of-charge control in the range of the state of charge. A battery input/output controller voluntarily controls the state of charge based on the central value of the state-of-charge control from the temperature rise controller and the state of charge at the point of time from the state-of-charge operator, and controls charge and discharge based on the charge and discharge request from the outside to the battery pack.

Abstract: The invention relates to an electronic apparatus whose power is supplied by a battery (11) having a memory (32) which contains electrically erasable data (32a) and a supply voltage detection device (37) for detecting a variation of the supply voltage (Vbat). The invention notably has for its object to provide a detection device (37) which is capable of instantaneously detecting various voltage levels to cut off the power supply (Vbat) without the contents of the memory (32) being changed and capable of indicating the charging level of a battery (11) or an overload. The invention may be used in portable telephones and other electronic equipment whose power is supplied by a power supply battery.

Abstract: A cost-effective power supply for providing full time electrical power to a customer premises telecommunications hub is disclosed. The supply includes an AC to DC power converter for converting power from the AC power grid to a DC voltage suitable for operating telecommunications equipment and for maintaining a backup battery at a fully charged float voltage. The converter includes a first rectifier section for generating an unregulated DC voltage. This voltage is switched through the primary of an isolation transformer by a pulse width modulated voltage controller. The output of the transformer is connected to a second rectifier circuit and filter to produce a regulated DC output voltage. The regulated voltage is connected to a voltage correction circuit through a divider including a temperature compensator so that the feedback to the voltage controller causes the regulated output voltage to follow the battery float voltage at all temperatures.

Abstract: A method for charging a secondary battery by measuring the static/open circuit voltage and comparing it to a predetermined value includes: a first step of precharging the secondary battery; thereafter pausing a predetermined interval; a step of measuring a secondary battery voltage Vba1 after performing the pausing; and a step of charging the secondary battery based on the measurement of the secondary battery voltage Vba1.

Abstract: A power accessory for apportioning electrical current between an electronic device and a rechargeable battery used in connection with the device includes two current limiting circuits. The first current limiting circuit limits the current supplied to the device to the peak current that device may demand. Any remaining current from the first current limiting circuit is passed through the second current limiter to the recharge the battery based on a charging algorithm. When the battery is fully charged, the second current limiting circuit stops providing current to the battery.

Abstract: An over-charging voltage is supplied from a voltage detecting circuit 39 to a priority controlling circuit 46 and a switch circuit 43. A voltage detecting circuit 41 detects a terminal voltage of a secondary battery BT (namely, an over-charging voltage) and supplies the voltage to the switching circuit 43. A current that flows in a resistor 42 is supplied to a cumulating circuit 40 and the switch circuit 43. The cumulating circuit 40 adds a voltage received from the voltage detecting circuit 39 through the priority controlling circuit 46 and a current that flows in the resistor 42 and supplies the added result as a control signal to a charging portion PS. A temperature detecting circuit 44 detects the temperature of a battery pack BP. The detected result is supplied to the switch circuit 43 and a detected voltage switching circuit 45. The switch circuit 43 performs on/off operations corresponding to the received voltage, terminal voltage, current, and temperature.

Abstract: A charging apparatus for charging a secondary battery of the present invention includes a DC/DC converter for outputting a preselected DC voltage and a preselected DC current limited by a voltage setting circuit and a current limiting circuit, respectively. A control circuit senses the voltage of a secondary battery connected to the apparatus and causes the current limiting circuit to set up a first current lying in a constant current range until the battery voltage reaches a full charge voltage. At this instant, the control circuit switches a charge switching circuit in order to apply the first current to the battery in the form of pulses. As soon as the battery voltage reaches the full charge voltage, the control circuit applies a current lower than the current in the constant current range and the current in the constant range to the battery alternately in the form of bilevel pulses.

Abstract: The present invention relates to a smart battery charging system, a charging method therefor and a power supply system for portable computer using the same that executes various charging operations securely corresponding to types of the smart batteries connected to the notebook computer. A smart battery charger 60 supplies charging voltage and charging current to the smart battery 70 selectively by controlling data input through an SM bus. The smart battery charger 60 and the smart battery 70 are connected to a keyboard controller 80 through the SM bus. The keyboard controller 80 determines the power on-off status of the notebook computer, based on second power voltage outputted from an SMPS 130, and identifies the types of the smart batteries, based on battery identifying signals outputted from the smart battery charger 60.

Abstract: A method (200) for charging a nickel cadmium, nickel-metal hydride or lithium-ion battery cell using an ultra-fast vehicular charging system includes determining (201, 203, 205) manufacturer identity, ultra-fast battery charging capability and battery capacity from the battery system to provide (207) battery type information. A direct current (DC) input voltage in a predetermined input supply voltage range is converted (211) to a an output supply current in a predetermined output voltage range. The predetermined output supply voltage is supplied (217) to the battery cell for recharging while a number of battery parameters are monitored (219) such as the battery cell voltage, charging current and temperature of the battery cell to generate monitoring information.

Abstract: A battery charger having a battery charger converter, which converter consists of a battery voltage detector for detecting the voltage of a secondary battery and a differential amplifier disposed between the battery voltage detector and an A/D converter. This battery charger is capable of reliably detecting when any battery has become fully charged, including inactive batteries such as batteries that are still warm from recently being discharged and batteries that have been inactive for a long period of time.

Abstract: Electronic equipment, for enabling a plurality types of batteries to be selectively used, which is designed in such a way that discharge characteristic data of a plurality types of batteries to be used is previously stored in a memory unit, a battery including a resistor indicating the type of the battery is fitted to the electronic equipment, the type of the battery is identified on the basis of a resistance value of the resistor, the discharge characteristic data of the battery corresponding to the identified type of battery is read out from the memory unit, a battery voltage is compared with the discharge characteristic data thus read out and a remaining power of the battery is calculated to display the information relating to the remaining power thus calculated.

Abstract: A battery charger and method of charging a rechargeable battery which comprises charging the battery with an initial charging current and measuring and comparing the charging temperature to an initial temperature to identify a temperature factor which either identifies a need to lower the current or terminate the charging current. The temperature factor may be a temperature gradient .DELTA.T. The open circuit voltage may be monitored from the beginning or may begin when .DELTA.T is identified. V.sub.OCV is plotted with respect to time t elapsed to identify a point or points on the V.sub.OCV (t) curve, such as an inflection point in the dV.sub.OCV /dt data or a transition point in the d.sup.2 V.sub.OCV /dt.sup.2 which indicate the onset of overcharge. If the open circuit voltage V.sub.OCV of the battery is sampled from the beginning of charging the second order differential information should be ignored until a predetermined temperature gradient is realized.

Abstract: A battery monitor and cycle status indicator is disclosed. The battery monitor includes a voltage sensor capable of sensing the voltage between two nodes, for example, the positive and negative terminals of a battery. The voltage sensor is connected to an analog-to-digital converter which converts the analog voltage level sensed by the voltage sensor to a digital form. In turn, the analog-to-digital converter is coupled to a microprocessor. The microprocessor determines battery state-of-charge and historical values that relate to battery condition based upon the voltage levels provided by the analog-to-digital converter. The microprocessor is also coupled to a memory which stores battery history values computed by the microprocessor and program instructions for operation of the microprocessor. The battery monitor also includes a display that is capable of displaying battery state-of-charge and the historical values determined by the microprocessor.

Abstract: The present invention provides a method for charging a secondary battery and a charger by which it can be prevented that a secondary battery is charged at very high or low temperature, and that the secondary battery is charged for a long time. Therefore, the secondary battery is prevented from being damaged, so that the lifetime can be prolonged. In this method, a generally constant current is supplied from a charging means to the secondary battery. The constant-current charging is stopped when voltage of the secondary battery has reached a peak value after passage of a predetermined time period from start of the supplying of the first current; temperature of the secondary battery has been out of a predetermined range; or a predetermined time period has passed since start of the supplying of the first current.

Abstract: A mode-convertible battery charging apparatus is provided. According to the invention, regardless of whether the battery being charged is a completely discharged battery, a fully charged battery or a battery which has a certain amount of electric charge, charging is automatically completed only after the battery is fully charged. Users can detect the charged state of the battery pack, and therefore life shortening of or a damage to the battery due to overcharging of the battery pack can be avoided so as to increase the reliability of the battery. When the detected voltage goes beyond the limit of automatic charging control, the charging operation is not conducted so as to prevent battery damage due to overcurrent.

Abstract: A power supply system, for example, for use with a portable personal computer, includes a smart battery pack and a charging system. The smart battery pack is provided with a dedicated microcontroller for controlling the charging level of the battery charger system. In particular, the status of the battery including the voltage and temperature of the battery is applied to the microcontroller along with a signal representative of the current load demand of the computer system. The micro controller, in turn, provides a control signal in the form of fixed frequency, variable duty cycle pulse width modulated (PWM) signal for controlling the charging level of the battery charger system. The duty cycle of the PWM signal is used to regulate the charging current supplied by the battery charger. In particular, the DC value of the PWM signal is used as a reference to control the charging current of the regulator to provide a variable output charging current with a relatively wide current range.