With Peak Detection Of Current Or Voltage (e.g., Delta-v Or Delta-i Utilized, Etc.) Patents (Class 320/148)
  • Publication number: 20080218129
    Abstract: A computer includes a system part which has at least one electronic component, a power supplying part which supplies a main electric power to the system part, a battery part which receives charging electric power from the power supplying part and supplies auxiliary electric power to the system part, and a controlling part which, if the main electric power is supplied by the power supplying part, and if charge level of the battery part according to supply of the charging electric power exceeds a reference level corresponding to a discharged state, cuts off the supply of the charging electric power and controls the battery part to discharge the auxiliary electric power.
    Type: Application
    Filed: February 25, 2008
    Publication date: September 11, 2008
    Applicant: Samsung Electronics Co., Ltd.
    Inventor: Chong Kyu Yun
  • Patent number: 7345455
    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.
    Type: Grant
    Filed: November 18, 2004
    Date of Patent: March 18, 2008
    Assignee: International Business Machines Corporation
    Inventor: Carl E. Jones
  • Patent number: 7265518
    Abstract: A method for automatically cutting off power in case of a low battery voltage in a mobile electronic unit is provided. The method comprises (a) cutting off the power of the mobile electronic unit when a battery voltage is detected in a first check section during a booting period of the mobile electronic unit that is not in a normal state, and (b) cutting off the power of the mobile electronic unit when the battery voltage detected with respect to the first check section is in the normal state and when a battery voltage is detected in a second check section during a period after booting of the mobile electronic unit is completed that is not in the normal state.
    Type: Grant
    Filed: January 20, 2004
    Date of Patent: September 4, 2007
    Assignee: Samsung Techwin Co., Ltd.
    Inventors: Yoo-shin Lee, Sung-youp Lee, Hun-young Ryu
  • Publication number: 20070178376
    Abstract: A lithium ion secondary battery includes a positive electrode, a negative electrode, a non-aqueous electrolyte, and a separator interposed between the positive electrode and the negative electrode. The separator includes a polyolefin layer and an oxidation-resistant layer. The oxidation-resistant layer includes an oxidation-resistant polymer. A main chain of the oxidation-resistant polymer does not include a —CH2— group and a —CH(CH3)— group. The oxidation-resistant layer faces the positive electrode.
    Type: Application
    Filed: January 26, 2007
    Publication date: August 2, 2007
    Inventors: Masato Fujikawa, Shinji Kasamatsu, Mikinari Shimada
  • Patent number: 7144646
    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.
    Type: Grant
    Filed: December 14, 2001
    Date of Patent: December 5, 2006
    Assignee: Ballard Power Systems Inc.
    Inventor: Martin T. Pearson
  • Patent number: 7135791
    Abstract: A controller compares a minimum value of power source voltage which decreases in association with starting current generated upon start of a motor with a threshold value in a storing unit. When the minimum value is less than the threshold value, the controller notifies of shortage of the power source terminal voltage, and stops the motor. The controller also compares a value obtained by integrating the power source voltage which decreases in association with starting current generated upon start of the motor for only predetermined time with the threshold value in the storing unit, when the integral value is less than the threshold value, notifies of shortage of the power source terminal voltage, and stops the motor.
    Type: Grant
    Filed: November 23, 2005
    Date of Patent: November 14, 2006
    Assignee: Maeda Metal industries, Ltd.
    Inventors: Toshihiko Kushida, Yukio Torigai
  • Patent number: 7019494
    Abstract: Disclosed is a method of charging a lithium-sulfur electrochemical cell wherein the lithium-sulfur cell comprises a cathode comprising an electroactive sulfur-containing material, an anode comprising lithium, and a nonaqueous electrolyte.
    Type: Grant
    Filed: January 6, 2004
    Date of Patent: March 28, 2006
    Assignee: Moltech Corporation
    Inventor: Yuriy V. Mikhaylik
  • Patent number: 6975080
    Abstract: A rotating electrical machine for a vehicle is capable of improving the acceleration performance and the fuel mileage of the vehicle while achieving the prevention of occurrence of overvoltage and the improvement of its power generation characteristic at the same time. The machine includes an armature having an armature core and an armature winding wound around the armature core for generating an output voltage to charge a battery; a rotor having a rotor core with a field winding wound therearound, and permanent magnets for supplying magnetic flux to the armature core; and a voltage control section that adjust the output voltage of the armature by controlling the field current based on the value of an output voltage of the armature winding and the value and the direction of flow of the field current flowing through the field winding.
    Type: Grant
    Filed: January 18, 2005
    Date of Patent: December 13, 2005
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Yutaka Kitamura, Yoshihito Asao
  • Patent number: 6956357
    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.
    Type: Grant
    Filed: April 11, 2005
    Date of Patent: October 18, 2005
    Assignee: Sony Corporation
    Inventors: Tamiji Nagai, Kazuo Yamazaki, Tadahisa Yamamoto
  • Patent number: 6949913
    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.
    Type: Grant
    Filed: April 11, 2005
    Date of Patent: September 27, 2005
    Assignee: Sony Corporation
    Inventors: Tamiji Nagai, Kazuo Yamazaki, Tadahisa Yamamoto
  • Patent number: 6859014
    Abstract: This invention includes a method for charging lithium-based batteries. Battery type is identified by a charger by way of a third terminal. For nickel-based cells, the third terminal is coupled to a thermistor for sensing temperature. For lithium-based cells, the third terminal is coupled to the rechargeable cell disposed within the battery pack. If a nickel cell is identified, the cell is charged by conventional means. If a lithium cell is identified, the charger applies a full current until any serial elements disposed between the battery pack terminals and the cell reach a high impedance state. The charger then reduces the charging current to a low level for a predetermined time. After this time has elapsed, the charger then reapplies a high current. If the voltage across the serial elements remains low, charging continues. However, if the voltage across the serial elements exceeds a predetermined threshold, the charger then decrements the current by a predetermined amount.
    Type: Grant
    Filed: December 17, 2002
    Date of Patent: February 22, 2005
    Assignee: Motorola, Inc.
    Inventors: William C. Bohne, John E. Herrmann
  • Patent number: 6801017
    Abstract: A four-stage charging technique for nickel-zinc cells and batteries, is provided, whereby a high cycle life is assured, without dendrite formation or harmful overchange, with minimal shape change of the zinc electrode, and with minimal oxygen, recombination. In the first stage, the nickel-zinc cell or battery is charged with an average current less than C/5 for a period for less than five minutes, or until the terminal voltage of a cell reaches 1.75 volts to 1.79 volts. In the second stage, a fast charge is imposed, until the terminal voltage of a cells reaches between 1.88 volts and 1.92 volts. In the third stage, a moderate charge is imposed, until the terminal voltage of a cell reaches 1.90 volts to 1.94 volts. The forth stage gives a trickle charge when the terminal voltage is greater then 1.94 volts.
    Type: Grant
    Filed: May 6, 2003
    Date of Patent: October 5, 2004
    Assignee: PowerGenix Systems, Inc.
    Inventor: Jeffrey Phillips
  • Publication number: 20040150372
    Abstract: A method for automatically cutting off power in case of a low battery voltage in a mobile electronic unit is provided. The method comprises (a) cutting off the power of the mobile electronic unit when a battery voltage is detected in a first check section during a booting period of the mobile electronic unit that is not in a normal state, and (b) cutting off the power of the mobile electronic unit when the battery voltage detected with respect to the first check section is in the normal state and when a battery voltage is detected in a second check section during a period after booting of the mobile electronic unit is completed that is not in the normal state.
    Type: Application
    Filed: January 20, 2004
    Publication date: August 5, 2004
    Applicant: Samsung Techwin Co., Ltd.
    Inventors: Yoo-shin Lee, Sung-youp Lee, Hun-young Ryu
  • Patent number: 6696815
    Abstract: A motor-generator is connected to a secondary battery via an inverter. The inverter is controlled by a hybrid (HV) ECU. A voltage sensor detects a voltage of each block of the secondary battery. A current value of the secondary battery is detected by a current sensor and supplied to a battery ECU. The battery ECU supplies the detected voltage to the HV ECU. The HV ECU compares the detected voltage against a predetermined threshold value at a high order of priority. If the detected voltage is the predetermined threshold value or lower, the HV ECU suppresses power consumption of the motor, thereby suppressing discharge of the secondary battery.
    Type: Grant
    Filed: November 12, 2002
    Date of Patent: February 24, 2004
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventor: Yoshiaki Kikuchi
  • Publication number: 20030169021
    Abstract: Device miniaturization is made possible by building a battery protection circuit in a microcomputer. A secondary battery protection device comprises a voltage detection means 7 that detects a voltage of a power supply circuit 6 including a secondary battery 1, a current detection means 8 that detects a current of the power supply circuit, and a battery protection circuit 10 that shuts off the power supply circuit 6 based on a signal representing a detection made by the voltage detection means 7 or the current detection means 8 of an excess current that is generated in the power supply circuit 6, wherein the protection circuit 10 is built in a microcomputer 13.
    Type: Application
    Filed: March 4, 2003
    Publication date: September 11, 2003
    Applicant: SEIKO EPSON CORPORATION
    Inventor: Takashi Kashine
  • Patent number: 6583605
    Abstract: In the invention, a plurality of batteries are connected in parallel with each other and are charged, and −&Dgr;V of a drop of a battery voltage from a peak voltage is detected to judge full charge, and currents flowing to the batteries connected in parallel are detected in the state where charging is stopped by the drop of −&Dgr;V. When the currents flowing to all the batteries are larger than a set current in the state where charging is stopped, it is judged that full charge is not attained and charging is resumed, and when the currents are smaller than the set current, it is judged that all the batteries are fully charged.
    Type: Grant
    Filed: February 5, 2002
    Date of Patent: June 24, 2003
    Assignee: Sanyo Electric Co., Ltd.
    Inventors: Tatehito Yagi, Takahiro Yamashita
  • Publication number: 20030112011
    Abstract: Computer-assisted methods for determining the state of charge of a specific lithium ion battery, without the need for charging and discharging the battery, by utilizing look-up tables or algorithms which store the relationships of state of charge to open-circuit voltage or to ramp-peak current, or to both for that type of specific lithium-ion battery to determine the state of charge for that specific lithium-ion battery.
    Type: Application
    Filed: January 23, 2003
    Publication date: June 19, 2003
    Inventors: James V. Guiheen, Harmohan Singh, Thirumalai G. Palanisamy
  • Publication number: 20030094926
    Abstract: A power supply unit, a distributed power supply system and an electric vehicle loaded therewith, capable of charge/discharge operation are disclosed. A first cell group is connected in parallel to a second cell group in which the electrolytic solution can be electrolyzed or the generated gas can be recombined. A plurality of the parallel circuit pairs are connected in series, and the series circuit is connected with a charger/discharger to constitute the power supply unit. The charger/discharger charges the power supply unit up to a voltage at which the electrolytic solution of the second cell group is electrolyzed or the generated gas is recombined.
    Type: Application
    Filed: October 9, 2002
    Publication date: May 22, 2003
    Applicant: HITACHI, LTD.
    Inventors: Akihiko Emori, Takuya Kinoshita, Hideki Miyazaki
  • Publication number: 20030003363
    Abstract: A lithium ion secondary battery comprising a positive electrode, a negative electrode, a separator and a nonaqueous electrolyte, wherein the separator consists essentially of a porous sheet, the positive electrode active material and the negative electrode active material can be reversibly doped and dedoped such that, where Qp (mAh) is an electric charge necessary for causing total lithium contained in the positive electrode to be dedoped and Qn (mAh) is an electric charge necessary for causing lithium to fully dope the negative electrode, Qp>Qn, and when the battery is charged at a charging current Ic (mA) in a range of 0.2Qn/h<Ic<2Qn/h, in a range of an electric charge for charging Qc (mAh) of 1<Qc/Qn<Qp/Qn, doping of the positive electrode by lithium is started through lithium particles produced on the negative electrode by charging of the battery and is continued up to Qc>Qp.
    Type: Application
    Filed: October 29, 2001
    Publication date: January 2, 2003
    Inventors: Takahiro Daido, Satoshi Igarashi, Satoshi Nishikawa, Hiroyuki Homoto, Hiroyoshi Minematsu
  • Publication number: 20020105305
    Abstract: In the invention, a plurality of batteries are connected in parallel with each other and are charged, and −&Dgr;V of a drop of a battery voltage from a peak voltage is detected to judge full charge, and currents flowing to the batteries connected in parallel are detected in the state where charging is stopped by the drop of −&Dgr;V. When the currents flowing to all the batteries are larger than a set current in the state where charging is stopped, it is judged that full charge is not attained and charging is resumed, and when the currents are smaller than the set current, it is judged that all the batteries are fully charged.
    Type: Application
    Filed: February 5, 2002
    Publication date: August 8, 2002
    Inventors: Tatehito Yagi, Takahiro Yamashita
  • Patent number: 6333621
    Abstract: In the method of fast-charging of a rechargeable battery, full-charge state is determined on the basis of a peak battery voltage or a decrease &Dgr;V in the battery voltage after the peak voltage. At the beginning of the fast-charge process, an initial battery voltage is measured. In case where the initial voltage is higher than a preselected voltage, the battery is fast-charged with a normal fast-charge current. In case where the initial voltage is lower than the preselected voltage, the battery is fast-charged with a restricted fast-charge current that is weaker than the fast-charge current.
    Type: Grant
    Filed: December 26, 2000
    Date of Patent: December 25, 2001
    Assignee: Sanyo Electric Co., Ltd.
    Inventor: Takahiro Yamashita
  • Patent number: 6127810
    Abstract: A method of controlling the charging of a rechargeable battery and a charger for practicing the same are disclosed. The battery voltage of the rechargeable battery, a voltage across the internal resistance of the battery and a voltage across a current setting resistor are added together and applied to the voltage detection input of a controller in the form of a sum voltage. The controller detects the sum voltages in the ON state (during charging) and OFF state(during interruption of charging) of a control FET (Field Effect Transistor), and calculates a difference between them. The controller determines, based on the difference, whether or not the battery has been fully charged, and then controls charging on the basis of the result of the decision.
    Type: Grant
    Filed: August 21, 1998
    Date of Patent: October 3, 2000
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Tsuneo Sato, Toshiharu Chuma
  • Patent number: 6100668
    Abstract: A battery to be charged is preliminary charged with a first charge current. If a presumption can be made such that the battery has reached a fully charged condition before expiration of a first predetermined period of time during which the battery is charged with the first charge current, it is determined that either a fully charged battery or an inactive battery is subject to charging. Then, the battery is preliminary charged with a second charge current. If a fully charged presumption can be made before expiration of a second predetermined period of time during which the battery is charged with the second charge current, it is determined that the battery is already fully charged, whereas if such a presumption cannot be made during the second predetermined period of time, it is determined that the battery is the inactive battery.
    Type: Grant
    Filed: January 11, 1999
    Date of Patent: August 8, 2000
    Assignee: Hitachi Koki Co., Ltd.
    Inventor: Nobuhiro Takano
  • Patent number: 6043631
    Abstract: A method of charging a rechargeable battery which comprises charging the battery with a charging current; sampling a charging voltage of the battery during charging to recognize potential adverse conditions within the battery; interrupting the charging current periodically to create current-free periods and sampling an open circuit voltage of the battery at a plurality of points during each current-free period to identify potential overcharge conditions in the battery; lowering the charging current if any of the above-identified adverse conditions are identified and continuing charging with the charging current if the potential adverse charging condition is not identified; and terminating charging when a negative slope on a chemical polarization versus time curve is identified below a pre-determined minimum level.
    Type: Grant
    Filed: January 2, 1998
    Date of Patent: March 28, 2000
    Assignee: Total Battery Management, Inc.
    Inventor: Boris Tsenter
  • Patent number: 6034510
    Abstract: The voltage of each of battery block of a battery is detected by a voltage sensor. Further, the temperature of the battery is detected by a temperature sensor. These detected values are supplied to a detecting section of a battery ECU. A judging section reads out the threshold value of the voltage stored in a memory, on the basis of the detected values of temperature, and compares the threshold value of the voltage with the detected voltage of each of the battery blocks. Then, if at least any one is less than the threshold value of the voltage, a relay is turned off. Furthermore, the threshold value of the voltage is arranged to be the voltage at the moment when the value of the current is suddenly increased by the discharge of a constant current of the battery.
    Type: Grant
    Filed: October 5, 1998
    Date of Patent: March 7, 2000
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventors: Yoshiaki Kikuchi, Fumihiko Asakawa, Toshiaki Nakanishi, Tadao Kimura
  • Patent number: 6034509
    Abstract: A battery-powered electrical device comprising a switchable voltage drain (3,5) and a rechargeable battery (1), and further comprising means for measuring the voltage V across the terminals of the battery (1) as a function of cumulative discharge time t, and for determining the cumulative discharge time t.sub.p corresponding to the attainment of the local extremum of least magnitude in the derivative dV/dt. In a particular embodiment, the device contains means for interrupting the voltage drain (3,5) upon expiry of a cumulative discharge time t.sub.e =nt.sub.p, whereby n is a fixed, pre-selected real number. In addition, it is possible to calculate and display the remaining discharge time t.sub.rem =m.sub.o t.sub.o -t, where m.sub.o is a fixed, pre-selected real number. The values of n and m.sub.o will generally be chosen to lie in the range 1.2-6.
    Type: Grant
    Filed: May 26, 1998
    Date of Patent: March 7, 2000
    Assignee: U.S. Philips Corporation
    Inventors: Robert E. F. Einerhand, Johann R. G. C. Van Beek, Jean N. Patillon
  • Patent number: 6005371
    Abstract: The invention provides a charging apparatus capable of charging a secondary battery regardless of a drive state of a set circuit such as a video camera and a personal computer, and having a simple circuit configuration which can be realized at low production costs. A first resistor Ro is provided between a power source and the set circuit 1 and a secondary battery 2. A current flowing to the first resistor Ro is detected by an amplifier A2. This detection result is used to control a total current Io flowing to a set main body 3 including the set circuit 1 and the secondary battery 2 as a unitary block. Simultaneously with this, a current flowing to the second resistor Rb is detected by an amplifier A3 and this detection result is used to control a charge current Ib flowing to the secondary battery 2.
    Type: Grant
    Filed: February 19, 1998
    Date of Patent: December 21, 1999
    Assignee: Sony Corporation
    Inventor: Koji Umetsu
  • Patent number: 5994872
    Abstract: A battery charger which supplies charging current for a high voltage, high current battery in accordance with a charge profile which preferably includes both a charge pulse sequence as well as a discharge pulse sequence. Charging power is obtained from a three phase power line the voltage of which is reduced by an isolation transformer. Conversion of ac to dc is accomplished by a switching transistor power converter having a control for supplying transistor switching signals. The control is responsive to the angle of line voltage, the actual line current and a reference signal indicative of desired charge current, to generate the transistor switching signals. Any deviation between actual and desired current is then corrected by modification of the transistor switching signals.
    Type: Grant
    Filed: July 1, 1998
    Date of Patent: November 30, 1999
    Assignee: Northrop Grumman Corporation
    Inventor: William B. Hall
  • Patent number: 5939865
    Abstract: A rechargeable battery is provided with an overcharge protection circuit which is particularly adapted for nickel metal hydride battery packs to be used in conventional charging adapters suitable for NI-CAD battery packs. The battery pack includes a microprocessor which measures the voltage across the electrical contacts of the battery pack. Upon reaching peak charge, the microprocessor increases the voltage appearing across the battery pack contacts. After a predetermined time period as measured by the microprocessor, the microprocessor decreases the voltage appearing across the battery pack terminals to exceed the change in voltage to which the charging adapter responds to terminate a high rate of charging.
    Type: Grant
    Filed: March 31, 1998
    Date of Patent: August 17, 1999
    Assignee: Aspen Electronics, Inc.
    Inventors: Francis D. McGrath, Norman D. Kellogg
  • Patent number: 5907232
    Abstract: Circuitry is added to charge storage devices including batteries which creates or enhances a minus delta V type of termination signal pattern to trigger a battery charger to terminate the battery charging. Circuitry, which is responsive either to a voltage or to a temperature, causes a switch to connect a load across the terminals of a battery to cause a voltage drop. The voltage drop triggers circuitry within the battery charger to terminate charging. For some applications, additional circuitry is added to cause a second switch to open to remove the load from the terminals upon the occurrence of a second specified event. The second specified event si defined by a specified voltage, temperature, or elapsed time value.
    Type: Grant
    Filed: May 5, 1997
    Date of Patent: May 25, 1999
    Assignee: Ericsson, Inc.
    Inventor: Ivan Nelson Wakefield
  • Patent number: 5898295
    Abstract: By monitoring both charge current and the battery voltage (306, 308) the likelihood of overcharging a battery is reduced. Battery voltage is compared to a predetermined limit (310) and the battery goes into trickle charge if the predetermined limit is exceeded (312), but now by also determining if a positive delta in charge current has occurred (314), the charger can trickle charge the battery (312) even if the cutoff voltage is never exceeded.
    Type: Grant
    Filed: June 9, 1997
    Date of Patent: April 27, 1999
    Assignee: Motorola, Inc.
    Inventors: Joseph Patino, Robert B. Ford
  • Patent number: 5867107
    Abstract: A battery powered electro-mechanical lock and method of actuating it under normal battery voltage level condition an access variation arrangement enables the lock to be opened upon the single entry of a correct access code and under low battery voltage levels conditions another access variation arrangements, which prevents the lock from being opened unless the user enters the correct access code N number of times, where N is between 2 and 24.
    Type: Grant
    Filed: June 3, 1997
    Date of Patent: February 2, 1999
    Assignee: Masco Corporation
    Inventor: Klaus W. Gartner
  • Patent number: 5864224
    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.
    Type: Grant
    Filed: October 29, 1996
    Date of Patent: January 26, 1999
    Assignee: Yamaha Hatsudoki Kabushiki Kaisha
    Inventors: Hiroaki Takechi, Tomohiro Ono, Masahito Suzuki
  • Patent number: 5838142
    Abstract: The charging voltage U.sub.L of the battery being charged is sensed and amplified by an amplification factor. The amplification factor is determined by the sensed charging voltage. This provides automatic scaling of the charging voltage. The amplification factor K can be repetitively or continuously adjusted during battery charging. The time behavior of the input signal is monitored. The monitoring unit determines whether the time behavior of the input signal fulfills predetermined or given criteria. When a criterion is met, a check-result signal is generated, which controls charging, for example, by stopping charging when the time behavior indicates charging is completed. Time behavior is monitored by monitoring a second order time derivative of the input signal. The monitoring unit performs optimally within a certain magnitude range. Therefore, the amplification factor is adjusted to set the input signal at a magnitude within that range.
    Type: Grant
    Filed: October 16, 1997
    Date of Patent: November 17, 1998
    Assignee: Impex Patrick Wyss
    Inventors: Patrick Wyss, Anton Fessler, Christian Meyer
  • Patent number: 5821736
    Abstract: A control circuit controls a battery charger so as to prevent damage to NiCAD or NiMH batteries resulting from overheating due to overcharging. During charging, the battery voltage is monitored through a filter, buffer, amplifier and sample and hold circuit. The sampled voltage is time differentiated to determine its rate of change, and a control signal is generated for switching the battery charger from a rapid charge mode to a trickle charge mode when the negative rate of change of the battery voltage exceeds a pretermined reference voltage, thereby identifying that the battery voltage has started to decay from its peak voltage.
    Type: Grant
    Filed: December 2, 1996
    Date of Patent: October 13, 1998
    Assignee: Samsung Electronics Co., Ltd.
    Inventor: Sang-Heum Yeon
  • Patent number: 5780994
    Abstract: A secondary battery charging method that utilizes a standard, characteristic reference curve for that type of battery for identifying the voltage inflection point during a constant-current charging process. The voltage response of a battery being charged is sampled periodically and compared to the reference curve to establish the degree of completion of battery charge by tracking the reference curve. The charging stage of the battery is determined as the fast-charge operation progresses by identifying a place on the reference curve corresponding to the observed response. When a satisfactory match is found, the time remaining to reach a fast-charge termination point is predicted by assuming that the voltage response will track the reference curve to the inflection point. Accordingly, the voltage response is no longer monitored and the time remaining to reach the inflection point is used to complete the fast-charge operation.
    Type: Grant
    Filed: March 21, 1997
    Date of Patent: July 14, 1998
    Assignee: Securaplane Technologies, L.L.C.
    Inventor: Christopher S. Sisemore
  • Patent number: 5770938
    Abstract: Methods and circuits are disclosed which terminate charging of a battery when the maximum charge is reached. Maximum charge is reached when the battery voltage has peaked, after a long rise, and just starts to drop. This small voltage drop, or delta, is detected by a charger control which compares the real time battery voltage with a previously sampled battery voltage. Upon detecting this small voltage drop, the charger control terminates the charging process. Implementations using an analog delta voltage detection and a digital delta voltage detection are described.
    Type: Grant
    Filed: December 9, 1996
    Date of Patent: June 23, 1998
    Assignee: Industrial Technology Research Institute
    Inventor: Hsueh-Wu Kao