Abstract: Described herein are a channel, system and method for monitoring voltages. Typically, the system includes multiple channels, each for sampling one of the voltages. The channels are physically and electrically coupled to a back end board on which is mounted a field programmable gate array (FPGA) that instructs the channels to simultaneously sample the voltages. Optionally, the channel is powered using an power supply that is isolated from the back end board, and transmits information over an electrically isolated connection to the back end board. The channel also includes voltage signal processing circuitry for processing the voltage signal on board the channel, and has stored on it channel identification information composed of at least one of an operating mode of the channel and a serial number of the channel, which can assist with voltage signal processing.

Abstract: Systems and methods for cell anomaly detection are provided. The disclosed systems and methods of cell anomaly detection may use a single circuit to detect both cell-open and imbalance conditions. Disclosed embodiments may incorporate a continuous or a sampled time system (i.e. cell anomaly detection is performed when an enable signal is active). An example embodiment includes receiving voltages of a plurality of cells of a battery pack; converting the received voltages to currents; determining a maximum current of the currents; determining whether at least one of the currents is anomalous; and reporting the at least one anomalous current as indicative of a bad cell.

Abstract: An arrangement (1) for measuring current on a high voltage battery (12) for an electrical vehicle, wherein the battery comprises a service disconnect switch (13) which is adapted to break the connection between the positive battery terminal (14) and the positive battery output terminals (15). The connection between the positive battery terminal (14) and the positive battery output terminals (15) comprises an external circuit line (21) extending out of the service disconnect switch (13) such that a loop is created, which is adapted to receive a current clamp for measuring the current through the circuit line (21).

Abstract: A battery system including: a battery, which includes at least one battery cell; a division circuit configured to receive a first voltage of the battery, generate a second voltage from the first voltage, and output the second voltage; an isolation circuit coupled between the battery and the division circuit, the isolation circuit being configured to electrically isolate the battery from the division circuit according to a control signal; and a battery management system coupled to the division circuit. The battery management system includes an isolation circuit control unit configured to generate the control signal; and a measuring unit configured to measure the second voltage.

Abstract: A battery system comprises plural battery cells, a voltage detecting circuit detecting voltage of each of the battery cells, and plural voltage detecting lines connecting an electrode terminal of each of the battery cells to input side of the voltage detecting circuit, and the voltage detecting circuit detects the voltage of each of the battery cells through the voltage detecting lines. The voltage detecting lines have different lengths, and at least one of the voltage detecting lines has a resistance adjusting portion which equalizes electrical resistances of the long voltage detecting line and the short voltage detecting line, and through the plural voltage detecting lines of which electrical resistances are equalized by the resistance adjusting portion, the voltage detecting circuit detects the voltage of each of the battery cells.

Abstract: An electric leakage detecting apparatus includes: a first voltage-dividing circuit; a second voltage-dividing circuit; a first switch which is inserted in a line connecting the first voltage-dividing circuit and the ground connection resistance; a second switch which is inserted in a line connecting the second voltage-dividing circuit and the ground connection resistance; a first voltage detecting circuit which detects an output voltage of the first voltage-dividing circuit; a second voltage detecting circuit which detects an output voltage of the second voltage-dividing circuit; and a judging circuit which judges whether the electric leakage of the high voltage battery occurs or not on the basis of the output voltage of the first voltage-dividing circuit in a case that the first switch is in ON state and the output voltage of the second voltage-dividing circuit in a case that the second switch is in ON state.

Abstract: Disclosed is an apparatus and method for diagnosing an abnormality in a cell balancing circuit in a battery pack including a plurality of cells corresponding to each cell balancing circuit. The present disclosure turns off cell balancing switches included in a cell balancing circuit to be diagnosed and an adjacent cell balancing circuit among the cell balancing circuits. Also, the present disclosure stores a voltage value between nodes of the cell (hereinafter referred to as a ‘diagnosis voltage value’) by turning on the cell balancing switch of the cell balancing circuit to be diagnosed. Also, the present disclosure calculates a difference value between adjacent cell voltage values (hereinafter referred to as a ‘cell difference value’) and a difference value between adjacent diagnosis voltage values (hereinafter referred to as a ‘diagnosis difference value’).

Abstract: In a battery monitoring system, an input current flowing through an input portion of an isolator member is larger than an output current flowing through an output portion of the isolator member. The output portion is electrically isolated from the input portion. The input and output portions of the isolator member are connected respectively to first and second circuits included in a group of the control circuit and the plurality of monitoring circuits. The first and second circuits are selected for the isolator member, The first and second circuits respectively serve as a sender and a receiver. The isolator member transfers serial data sent from the sender to the receiver while the sender and the receiver are electrically isolated from each other. The isolator is mounted on a substrate included in the control and monitoring substrates. The receiver is mounted on the substrate.

Abstract: A state-of-charge estimation apparatus connected to a power storage device having cell batteries, and estimating a state of charge of the power storage device, the apparatus including a first SOC computation unit computing a current integration value based on a total current from a current detector detecting the total current flowing to the storage device from a power conversion device using a previous SOC value as an initial value, and outputting the integration value as a first state-of-charge estimated value, and a second SOC computation unit estimating, after discharge suspension in the storage device, an open-circuit voltage based on a total voltage on a connection point between the conversion device and the storage device, a previous value of the total voltage, and a gain with time passage after discharge suspension in the storage device, and outputting the open-circuit voltage as a second state-of-charge estimated value.

Abstract: A battery monitoring apparatus capable of reducing power consumption. At least one monitoring integrated circuit (IC) is electrically connected to a high-voltage battery formed of a plurality of cells and configured to monitor the high-voltage battery in a plurality of modes of operation. A low-voltage power supply circuit can deliver power of a lower voltage than the power of the high-voltage battery to the at least one monitoring IC. A power supply to the at least one monitoring IC is selected from a group of the high-voltage battery and the low-voltage power supply circuit depending on the mode of operation the at least one monitoring IC.

Abstract: A method is provided for current-based detection of an electrical fault in an electrical network of a motor vehicle, the network having at least: one battery, one pulse-controlled inverter, one d.c. voltage converter, and an intermediate circuit associated with the pulse-controlled inverter. The method includes: detecting magnitudes of each a battery current, a d.c. voltage converter current, and an intermediate circuit current; comparing current magnitudes according to provided equations; and checking based on the comparison of whether a specifiable deviation has been exceeded. An alternative method for voltage-based detection of an electrical fault in an electrical network of a motor vehicle includes: detecting magnitudes of each a battery voltage, a d.c. voltage converter voltage, and an intermediate circuit voltage; comparing voltage magnitudes according to provided equations; and checking based on the comparison of whether a specifiable deviation has been exceeded.

Abstract: A battery condition estimating apparatus for a battery pack having a plurality of battery cells connected in series includes an analog channel switching circuit and a battery gas gauge circuit. The analog channel switching circuit has a plurality of input ports and an output port, wherein the input ports are coupled to the battery cells via a plurality of analog channels, respectively, and the analog channel switching circuit is arranged to couple the output port to a selected input port of the input ports for allowing the output port N5 to be coupled to a selected battery via a selected analog channel. The battery gas gauge circuit is coupled to the output port of the analog channel switching circuit, and used for estimating a battery condition of the battery pack by monitoring the selected battery cell via the selected analog channel.

Abstract: In a voltage monitoring system, a voltage monitoring module includes an adjusting current control circuit to generate an adjusting current so that the operating current consumed by the voltage monitoring modules reaches a specified value corresponding to a first operation current setting command, and stops generating the adjusting current according to an operating current switching command; and an operating current measurement circuit to measure the operating current according to the operating current measuring command following the operating current switching command; and in which a module control circuit sends a second operation current setting command based on the operating current that was measured, and the adjusting current control circuit generates an adjusting current so that the operating current reaches a specified value corresponding to the second operating current setting command.

Abstract: A cell monitoring device for monitoring cells connected in series in an electric storage module includes electric lines, switches connected in parallel to the cells, respectively, via the electric lines, and a controller. The controller configured to: close and reopen at least two of the switches; measure voltages between the lines connected to the cells after the switches connected in parallel to the cells are reopened; determine the measured voltages as cell voltages of the cells; determine whether at least one of a high abnormality voltage equal to or higher than a first threshold and a low abnormality voltage equal to or lower than a second threshold lower than the first threshold exists among the cell voltages; and determine at least one of the electric lines has lost continuity if at least one of the high abnormality voltage and the low abnormality voltage exists among the cell voltages.

Abstract: A wiring module is attached to an electric cell group that includes a plurality of electric cells, the wiring module having a resin protector that is attached to the electric cell group, connection bus bars and output bus bars that are connected to electrode terminals of the electric cells and that are held on a side of the resin protector that is opposite to a side facing the electric cell group, voltage detection terminals for detecting states of the electric cells, the voltage detection terminals being held by the resin protector, and detection wires that are drawn from the voltage detection terminals. In the resin protector, an output bus bar holding portion that holds the output bus bars is provided, on the surface facing the electric cell group, with a guide portion in which the detection wires are routed.

Abstract: A controller, a first voltage detector, a second voltage detector, . . . and an nth voltage detector are connected together in series in this order via a common communication line. In ID setting operation, the controller transfers a unique ID of the first voltage detector to the first voltage detector via the communication line, and transfers a unique ID of the (i+1)th voltage detector to the (i+1)th voltage detector via the first to ith voltage detectors and the communication line (where in is a natural number equal to or less than (n?1)).

Abstract: A route switching circuit includes: a pair of normal detection routes that output voltages of a positive side connection point and a negative side connection point, which are different from each other, in multiple batteries for constituting an assembled battery; and a pair of diagnosis detection routes that output the voltages of the positive side connection point and the negative side connection point, and confirm a connection state of the normal detection routes by using the normal detection routes, which output at least one of a voltage of a positive side battery connected to a positive side from the positive side connection point and a voltage of a negative side battery connected to a negative side from the negative side connection point.

Abstract: A system and method for use characterizing battery cells. Charging and/or discharging characteristics for each of a plurality of battery cells may be determined, the battery cells may be marked based on the determined charging and/or discharging characteristics, and grouped based on the marking—e.g., such as battery cells having similar or near similar charging and/or discharging characteristics are grouped together. Battery packs may then be assembled such that each battery pack would comprise only battery cells belonging to the same group (or “in-family”). The charging characterization may be based on voltage rise curve, which may be determined for each battery cell—e.g., based on sampling or recording during charging, at sufficient rate. Battery cells may subsequently be monitored, during use of the battery packs, to ensure that the charging or discharging does not change, and battery cells exhibiting change in characteristics may be manually or automatically removed from use.

Abstract: A fuel cell system includes a fuel cell, a multiphase voltage conversion device with N-phases (N being an integer equal to or larger than two) that is connected to the fuel cell, a control signal generation portion that generates control signals to control each phase of the multiphase voltage conversion device by superimposing a control waveform for measuring impedance on a voltage indicating an output target voltage of the multiphase voltage conversion device and sequentially outputs the control signals corresponding to N phases with a predetermined phase difference to the multiphase voltage conversion device, and an impedance calculation portion that measures a current and a voltage of the fuel cell on cycles corresponding to N predetermined sampling frequencies having a phase difference equal to the predetermined phase difference and calculates an impedance of the fuel cell based on the measured current and the measured voltage.

Abstract: A busbar for battery electrode post connection with a terminal for voltage detection is provided. Both ends of a length direction of a rectangular thin plate of a conductive metal are left and an elongated opening is formed in a center. Two holes through which an electrode post of one battery and an electrode post of an adjacent battery are inserted are respectively formed in the rectangular thin plates of both sides around the elongated opening of the center. A terminal for voltage detection is extended integrally to the rectangular thin plate from an edge of the rectangular thin plate. The two holes overlap in a state of where the rectangular thin plate is folded in two with respect to the elongated opening. The terminal for voltage detection can be erected from the rectangular thin plate by folding the terminal for voltage detection in a vertical direction.

Abstract: An electronic storage module includes a plurality of batteries, a primary monitoring circuit configured to detect an operating state of the plurality of batteries, a microcontroller unit connected to the primary monitoring circuit via a primary communication path, and a secondary monitoring circuit connected to the microcontroller unit via a secondary communication path. The secondary monitoring circuit is configured to detect the operating state of the plurality of batteries when a determination is made of an abnormality in the primary communication path, or an abnormality in the operating state of the primary monitoring circuit.

Abstract: A method for determining the charge state of a battery pack consisting of a number “N” of individual battery cells, includes determining the charge state of each individual battery cell SOCi for all i=1,N. The mean value of the charge states of the individual battery cells, mean (SOCi), is also determined. The method further includes determining a weighting “w” from the equation where w=gw(mean(SOCi)). The following applies for the function gw(SOC): the function value tends towards a minimum value of wmin when the argument tends toward the minimum charge state of a complete discharge SOCmin. The function value tends toward a maximum value of wmax when the argument tends towards the maximum charge state of a complete charge SOCmax; and the function gw( ) is continuous.

Abstract: A testing device for solid oxide fuel cell (SOFC) is disclosed. The testing device which combines the original cell housing with a four-point probe equipment is set for measuring SOFC MEA. The current collectors on anode and cathode in the original cell housing are respectively replaced by four independent probe units. They are not only to collect current but also to become measuring probes. Therefore, the lateral impedance of anode and cathode can be measured. Furthermore, the local characteristics are examined by open circuit voltage (OCV), I-V curve, and electrochemical impedance spectroscopy (EIS) measurements. The results show that the lateral impedance is substantially varied with temperatures. The distributions of OCV, current density, EIS and cell voltage in long-term test at the center of the cell are different from the edge.

Abstract: In a method for monitoring a battery which includes a number of cells, in each instance, at least one electronic unit is situated so as to be in contact with at least two of the cells, in order to record a variable of this cell and forward it to a central receiver.

Abstract: A measurement device for measuring voltages along a linear array of voltage sources, such as a fuel cell stack, includes at least one movable voltage probe that measures voltage transitions along an array element. The measured voltage is used to determine a distance of travel of the at least one voltage probe along the fuel cell stack from the speed of the probe and the timing of the transitions.

Abstract: A battery monitoring system includes a plurality of battery monitoring devices connected to a battery formed by connecting a plurality of battery cell groups in series, and monitor a state of the battery for the respective battery cell groups, each of the plurality of battery cell groups being of one or a plurality of battery cells connected in series, and a controller that performs wireless communication with the plurality of battery monitoring devices. First identification information portions which are different from each other are set in the plurality of battery monitoring devices in advance, and second identification information corresponding to an order of potentials of the battery cell groups in the battery, to which the battery monitoring devices are connected, is assigned to each of the plurality of battery monitoring devices. The controller stores a relationship between the first and second identification information for each battery monitoring device.

Abstract: According to an embodiment of the disclosure, a method for monitoring a battery pack is provided. The battery pack includes a plurality of modules and a pack controller, and each module includes a corresponding module controller. For each module, the method includes measuring a module current and measuring a module voltage. The measured module current and the measured module voltage are compared to state of health (SOH) data in at least one dynamic look-up table. A state of charge for the module is determined based on the comparison of the measured module current and the measured module voltage to the SOH data in the dynamic look-up table. For a particular embodiment, the dynamic look-up table is initially configured based on a type of battery chemistry for the battery pack, and after each charge cycle for the module, the dynamic look-up table is updated based on empirical data for the module.

Abstract: Provided are an apparatus and a method for diagnosing an abnormality in a cell balancing circuit. The apparatus may include a plurality of cell balancing circuits respectively connected to a plurality of battery cells included in a battery pack for balancing the voltages of the battery cells, a diagnosis resistor respectively installed between the cell balancing circuit and a cathode terminal and an anode terminal of the corresponding battery cell, a voltage measuring unit for measuring a voltage difference of the balancing circuit corresponding to each of the battery cells, and a control unit for turning on or off a cell balancing circuit to be diagnosed and for determining whether there is an abnormality in the cell balancing circuit to be diagnosed, based on a variation pattern of a voltage difference of a cell balancing circuit adjacent to the cell balancing circuit to be diagnosed that is measured by the voltage measuring unit.

Abstract: A system for power balance monitoring in an energy storage battery comprising a plurality of energy modules connected in a series-parallel configuration. The energy storage module comprises a plurality of cells. Each module is a three-terminal module. The three terminals comprise a positive output terminal and a negative output terminal for connecting the modules in a series string to a load and an energy sharing terminal for sharing energy between modules is other battery strings. A module power management sub-system comprising a current monitoring circuit is connected to each of the energy sharing terminals. Each module power management sub-system is in communication with a battery power management sub-system so that a weak module can be detected based on module current output. Advantageously, the module power management sub-system is not connected across the main power pathway of the module and so does not appreciably increase module impedance.

Abstract: Lower order control devices control plural battery cells configuring plural battery modules. An input terminal of the low order control device in the highest potential, an output terminal of the low order control device in the lowest potential, and a high order control device are connected by isolating units, photocouplers. Diodes which prevent a discharge current of the battery cells in the battery modules are disposed between the output terminal of the low order control device and the battery cells in the battery module on the low potential side. Terminals related to input/output of a signal are electrically connected without isolating among the plural low order control devices.

Abstract: A battery cell balancing system is operable to utilize a relatively small number of transformers interconnected with a battery having a plurality of battery cells to selectively charge the battery cells. Windings of the transformers are simultaneously driven with a plurality of waveforms whereupon selected battery cells or groups of cells are selected and charged. A transformer drive circuit is operable to selectively vary the waveforms to thereby vary a weighted voltage associated with each of the battery cells.

Abstract: A battery voltage monitoring circuit includes a first power supply terminal to be connected to the positive terminal of a battery pack having rechargeable cells connected in series; a first supply voltage sensing terminal to be connected to the positive terminal of the battery pack; a first resistor connected between the first power supply terminal and the first supply voltage sensing terminal; a second supply voltage sensing terminal to be connected to the negative terminal of a first rechargeable cell of the rechargeable cells, the first rechargeable cell being on the positive terminal side of the battery pack and connected to the positive terminal of the battery pack; a second resistor connected between the second supply voltage sensing terminal and the first power supply terminal; and a first comparator configured to compare a voltage at the first power supply terminal and a voltage at the first supply voltage sensing terminal.

Abstract: The present invention serves to reduce the costs associated with the overall life cycle of storage batteries by performing support so that a plurality of batteries are transferred between and used at a plurality of facilities. This storage battery transfer support device comprises: a collection unit that collects battery information representing the status of each battery used at a plurality of facilities; a battery information storage unit that stores the battery information collected by the collection unit; and a deterioration prediction unit that, on the basis of the battery information stored in the battery information storage unit, predicts deterioration of storage batteries that have been transferred between and used at a plurality of facilities.

Abstract: An energy storage system includes a plurality of battery units; a plurality of thermistors detecting a temperature of the plurality of battery units; a multiplexer performing multiplexing on the plurality of thermistors, and connecting a thermistor selected from among the plurality of thermistors to a reference resistor; a power switch unit arranged between the reference resistor and a power voltage terminal; and a control signal input unit receiving a control signal applied to the multiplexer and the power switch unit, and receiving two or more control bits contained in the control signal. In the energy storage system, a temperature measurement operation is performed at a plurality of measurement positions, whereby a current state of a battery may be accurately detected, an entire circuit may be reduced and simplified, and low power consumption may be realized.

Abstract: A battery-state monitoring system capable of efficiently estimating the state and service life of each storage battery at high precision by automatically measuring or acquiring various parameters of a plurality of storage batteries constantly connected to an equipment is provided. The system monitors a state of each of a plurality of batteries connected in series and constituting an assembled battery incorporated in an equipment includes a power supply control device that detects a current flowing through each battery; and an end device that measures a temperature, a voltage, and internal resistance of each battery, the internal resistance being measured by using at least two or more kinds of frequencies, and degradation of each battery is estimated based on one or more temperature, voltage, and internal resistance.

Abstract: A cell voltage measuring apparatus of a battery pack comprises a plurality of multiplexers connected corresponding to each cell group of the battery pack and operated to output a voltage signal of each cell in each cell group based on a reference potential applied from a corresponding cell group; a plurality of floating capacitors connected corresponding to each cell in each cell group and on which the voltage of each cell is charged and held; a switching means for enabling the voltage of each cell to be charged and held on each corresponding floating capacitor; and a controller for controlling the switching means per each cell group to enable the voltage of each cell to be charged and held on each corresponding floating capacitor and controlling each multiplexer to measure the cell voltage held on each floating capacitor of each cell group connected to each corresponding multiplexer.

Abstract: The invention relates to an evaluation circuit for detecting the voltage in battery cells of a battery system which are preferably connected in series. The evaluation circuit includes serially connected resistors, the number of which is equal to the number of battery cells for which the voltage is to be detected. One of the resistors is associated with each of the battery cells.

Abstract: A device for measuring voltages of N cells in a fuel cell includes plural voltage measurement modules and a communication bus connecting in series the plural measurement devices to a computer. The N cells are separated by bipolar plates. Each module can measure M voltages on a group of adjoining cells of the fuel cell, with M being a natural number, and with M?N/2. A group of cells measured by a first module is adjacent to group of cells measured by a second module. Each module includes a mechanism for fixing the module onto the fuel cell, a voltage measurement device, a connector for connecting bipolar plates of the module to the voltage measurement device, and a connector for connecting the voltage measurement device to the communication bus. A last bipolar plate connected to the first module also is connected to the second module.

Abstract: A voltage detection apparatus comprises discharge circuits constituted by switch elements and resistors connected in series, and respectively connected in parallel to each of a plurality of battery cells constituting a storage battery, filter circuits provided for the respective battery cells and removing noise contained in voltage inputted by the battery cells, and voltage detection units (D) and (M) which detect voltage of the respective battery cells in which noise is removed by the filter circuits. The voltage detection units correct detection results, based on time from when the switch elements of the discharge circuits change into an OFF state to timing for detecting voltage of the battery cells. With this voltage detection apparatus, it is possible to correct the detection error of the voltage of the battery cell due to the influence of the filter circuit, thus improving the detection accuracy of the voltage of the battery cell.

Abstract: A battery cell unit includes a battery cell and a monitoring and actuation unit for monitoring the function state of the battery cell. A coupling unit is provided in the battery cell unit, in which coupling unit two half-bridges forming a full-bridge are arranged, which half-bridges each comprise a first power semiconductor coupled to a positive pole of the battery cell, a second power semiconductor coupled to a negative pole of the battery cell and a central connection and are connected to a respective other output terminal of the battery cell unit via the respective central connection. The battery cell is configured to operate, in the normal operating mode, the power semiconductors of the half-bridges in such a way that a battery cell voltage of the battery cell is present at the output terminals of the battery cell unit optionally with a positive or negative orientation.

Abstract: A method for short detection in a battery pack, the battery pack including a plurality of cells, the method including: connecting a short detection module to the battery pack; determining by the short detection module that the battery pack is at rest; and selecting a first cell in the battery pack for testing for a short, wherein the testing includes: connecting a voltage source to the first cell; measuring a current of the first cell; and determining based on the measured current of the first cell whether the first cell contains a short.

Abstract: Improvements to industrial battery monitoring devices include improved circuitry to make the device polarity insensitive and to allow it to operate over a wide range of battery voltages.

Abstract: There is provided a semiconductor circuit including: a selection circuit, to which are connected batteries in series, and which selects any one of the batteries; a difference detecting circuit, to which voltage of a high potential side of the selected battery inputted, and to which voltage of a low potential side of the selected battery is inputted, and which outputs a difference between the voltage at the high-potential side and the voltage at the low-potential side; and a voltage applying unit that applies diagnostic voltage to a wire that is for inputting the high potential voltage to the difference detecting circuit when diagnosing an abnormality of a wire associated with the selected battery if the selected battery is a battery of a highest position in the series or a battery of a lowest position in the series.

Abstract: Disclosed is an apparatus and method for diagnosing an abnormality in a cell balancing circuit in a battery pack including a plurality of cells corresponding to each cell balancing circuit. The present disclosure turns off cell balancing switches included in a cell balancing circuit to be diagnosed and an adjacent cell balancing circuit among the cell balancing circuits. Also, the present disclosure stores a voltage value between nodes of the cell (hereinafter referred to as a ‘diagnosis voltage value’) by turning on the cell balancing switch of the cell balancing circuit to be diagnosed. Also, the present disclosure calculates a difference value between adjacent cell voltage values (hereinafter referred to as a ‘cell difference value’) and a difference value between adjacent diagnosis voltage values (hereinafter referred to as a ‘diagnosis difference value’).

Abstract: A battery control device for a battery module includes a plurality of integrated circuits. Each integrated circuit includes: a constant voltage circuit that lowers a total voltage of a battery cell group corresponding to the integrated circuit to an integrated circuit internal voltage; a signal generation circuit that generates, based upon a first signal provided by a higher-order control circuit, a second signal assuming a wave height value different from a wave height value of the first signal and outputs the second signal; and a startup circuit that includes a first comparator assuming a first decision-making threshold value corresponding to the first signal and a second comparator assuming a second decision-making threshold value corresponding to the second signal, and starts up the constant voltage circuit in response to a change in an output from at least either the first comparator or the second comparator.

Abstract: A method and an apparatus using a power transistor in a fuel cell stack diagnostic system provides an apparatus using a power transistor in a fuel cell stack diagnostic system. The apparatus includes a regenerative braking detector that detects regenerative braking of a fuel cell vehicle equipped with a fuel cell stack diagnostic system; a voltage rise determiner that determines whether a voltage rise due to regenerative braking of a fuel cell vehicle is a predetermined value or more; and a power transistor controller that controls an AC signal generator so that the voltage due to the regenerative braking is discharged by the power transistor, when the voltage rise due to regenerative braking determined by the voltage rise determiner is a predetermined value or more.

Abstract: Disclosed are a voltage measuring apparatus and a battery management system including the same. The voltage measuring apparatus is connected to a plurality of battery cells connected to each other in series to measure respective voltage of the battery cells. The voltage measuring apparatus includes a first node coupled to one of an positive electrode and a negative electrode of one of a plurality of battery cells as a voltage measuring target, amplifies a voltage difference between the first node and the second node to generate an error voltage, converts the error voltage into a digital signal, and compensates for a polarity of the digital signal.

Abstract: The voltage measuring apparatus is connected to a plurality of battery cells connected to each other in series to measure respective voltages of the battery cells. The voltage measuring apparatus includes a sample/hold amplifier configured to sample and hold positive electrode and negative electrode voltages of the battery cells to generate first and second output voltages, a differential voltage converter configured to generate a battery cell voltage according to a voltage difference between a positive input terminal and a negative input terminal, and a switching unit configured to control the first and second output voltages and connection between the positive input terminal and the negative input terminal so that a polarity of the voltage difference is constant. The sample/hold amplifier electrically insulates the switching unit from the battery cells.

Abstract: An assembled battery management system has an assembled battery having a plurality of battery modules connected in series, wherein each of the battery modules has a plurality of battery cells connected in series, a connection member that connects the plurality of battery modules, and a battery voltage detection device that detects voltages of the battery cells. The battery voltage detection device has a monitoring section having a voltage detector that detects the voltages of the battery cells, wherein the monitoring section monitors the voltages of the battery cells based on a detection result of the voltage detector, and a plurality of voltage input terminals connected to the monitoring section. Each of the battery modules includes a plurality of voltage detection terminals connected to a positive electrode and a negative electrode of each of the modules as well as connecting points of the battery cells.

Abstract: A device for measuring a maximum cell voltage among cell voltages of a plurality of battery cells connected in series includes a plurality of ohmic resistors connected in series. The device is configured to be connected to a plurality of battery cells connected in series in such a way that a respective battery cell is associated with each ohmic resistor according to the series connections. Each ohmic resistor, with the exception of a first ohmic resistor, is configured to conduct the larger of (i) a current that corresponds to the cell voltage of the associated battery cell, and (ii) the current that is conducted by the preceding ohmic resistor in the series connection.