Abstract: A battery condition detector configured to detect a micro short circuit of a rechargeable battery is disclosed. The battery condition detector includes a processing part configured to calculate the remaining capacity and the full-charge capacity of a rechargeable battery 200 and to determine the micro short circuit of the rechargeable battery 200 by detecting an overcharge of the rechargeable battery 200 based on a charged capacity charged during the charging of the rechargeable battery 200, the remaining capacity calculated at a calculation time immediately before the start of the charging, and the full-charge capacity calculated before the start of the charging; and a communications part 70 configured to output a signal according to the determination result of the processing part 50.

Abstract: A plurality of augmented batteries each have internal communication circuitry and current monitoring circuitry allowing them to communicate current usage signatures with one another. Based on analysis of those respective signatures each augmented battery determines if it is “paired” with other batteries, by virtue of being installed in the same device. The augmented batteries use knowledge of pairing to control how they collectively behave to provide augmented functionality, such as alerting the user regarding the charge level within the batteries.

Abstract: A system and method for identifying and responding to exceptional charge events of series-connected energy storage elements.

Abstract: The present invention provides a battery module state detection method. The battery module includes a battery unit and is connected to a load. The method for detecting the battery module status includes the following steps. First, measure an on-load voltage value of the battery unit and a load current value of a load. Next, calculate an instant resistance value of the battery unit according to a no-load voltage value of the battery unit, the on-load voltage value and the load current value. Finally, obtain an operating state of the battery unit according to the instant resistance and a relationship between the internal resistance and discharging time. By the method of the present invention, the user can monitor the remaining energy of the battery module accurately in real time and therefore prevent the electrical hazard caused by over-discharging the battery module.

Abstract: An accumulator control device includes a first electrical connection configured to connect the accumulator control device to a local accumulator. A second electrical connection is connected to the first electrical connection and configured to connect to a remote auxiliary electrical power supply device. A control unit is configured to measure at least one of a parameter of the accumulator and an environmental parameter and to transmit at least one of the at least one measured parameter and a value calculated using the at least one measured parameter to the remote auxiliary electrical power supply device via a communication interface.

Abstract: A testing system and a method for testing a battery cell are provided. The system includes a nest member that receives the battery cell, and a clamping device that secures a first battery tab between first and second connectors, and secures a second battery tab between third and fourth connectors. The system further includes a voltmeter that measures a voltage level between the first and third connectors when the first and second battery tabs are contacting the first and third connectors, respectively. The system further includes an ohmmeter that measures a first resistance level between a first portion of the outer housing and the first connector when the first battery tab is contacting the first connector.

Abstract: An internal resistance testing device includes an excitation source and a battery pack, an adjustable resistance R, a sampling unit, and a control unit. The excitation source and the battery pack form a loop circuit. The adjustable resistance R may be located at the loop circuit formed by the excitation source and the battery pack. The sampling unit samples the voltage between two sides of the battery pack, the voltage between two sides of the adjustable resistance R, and the value of the adjustable resistance R. The control unit calculates internal resistance of the battery pack according to the signal value collected by the sampling unit. The internal resistances of different voltage-ranges the battery pack are determined by adjusting the value of the adjustable resistance R to cause the actual excitation voltage to be equal to the range voltage of the sampling unit.

Abstract: Improved protection for a rechargeable battery from damage by being discharged below a cut-off voltage is provided. The measured voltage of a battery under load is lower than the measured voltage of the battery under no load. As the cut-off voltage for the battery is specified as a no load voltage, comparing the measured voltage of the battery under load to the cut-off voltage would result in stopping use of the battery with useable charge remaining. Through testing, a set of relationships for estimating the no load voltage of a battery under load has been determined. Using this set of relationships with battery measurements, an estimated no load voltage for the battery is determined. This estimated no load voltage is compared to the cut-off voltage. This allows for full use of the battery while stopping use of the battery when its voltage reaches the cut-off, thereby preventing damage.

Abstract: The invention relates to a system for estimating the end-of-charge time of a battery connected to a battery charger on board a motor vehicle. The system is characterised in that it comprises a means (1) for determining the charge status of a battery, a means (6) for determining the charge power of the battery charger and a means (11) for determining an end-of-charge time.

Abstract: A lighting system (10) is provided that includes at least one lighting device (14A,14B,14C), a plurality of external power sources (20,22,24,26,27) and an internal power source (16) applying a first electrical current to illuminate at least one lighting source (18A,18B,18C), wherein the internal power source (16) supplies the first electrical current. Further, a fuel gauging system and method (1230) detects an electrochemical composition of a power source (16,20,22,24,26,27), which can be at least one of the internal power source (16) and the external power source (20,22,24,26,27), and then determines a state of charge of the power source (16,20,22,24,26,27) based upon the determined electrochemical composition of the power source (16,20,22,24,26,27).

Abstract: An anti-fake battery pack and an identification system thereof has a casing and multiple battery cells, each of which as a battery body, an inner identifier mounted outside the battery body, a protection layer mounted around outside of the battery body and the outer identifier formed on the protection layer. An external identifying device has to read a first and second identification codes from the inner and outer identifiers to determine whether the battery cell is authentic or not. In addition, the inner identifier is covered by the protection layer, so the inner identifier can not stolen without breaking the protection layer with the outer identifier. Therefore, the identifying system provides double identifying procedures to increase security of identification and decrease the possibility of copying the first and second identification codes.

Abstract: A battery tester capable of measuring resistance and voltage of a battery using the same input channel. When measuring battery resistance, a testing signal circuit is electrically coupled to two electrodes of a subject battery to conduct a testing signal used in the battery resistance measurement. A response sensing circuit of the battery tester is also electrically coupled to the two electrodes of the subject battery to measure a response signal across the two electrodes of the subject battery. A resistance measuring module is electrically coupled to the response sensing circuit to measure the battery resistance based on the response signal detected by the response sensing circuit. A circuit breaker is capable of disconnecting the subject battery from the testing signal circuit, and disconnecting the resistance measuring module from the response sensing circuit. Moreover, the battery tester can also provide automatic protection for the battery resistance measuring module.

Abstract: Disclosed is an isolation resistance measuring apparatus having a fault self-diagnosing function. The isolation resistance measuring apparatus having a fault self-diagnosing function forms a diagnosis circuit by means of a first isolation resistance measuring unit and a second isolation resistance measuring unit respectively connected to a cathode terminal and an anode terminal of a battery, and includes a control unit for determining whether a fault arises at the isolation resistance measuring apparatus by using a circuit equation derived from the diagnosis circuit and first and second diagnosis voltages. Therefore, the isolation resistance measuring apparatus may diagnose whether a fault arises at a device which measures isolation resistance of a battery.

Abstract: A battery cell measurement system comprising a signal generator coupled to a pulse density modulation circuit generating a control signal which drives a switch connected between a first terminal of a battery cell and a first terminal of a bleeding impedance, a second terminal of the bleeding impedance being coupled to a second battery cell terminal. The first terminal is coupled to a first terminal of a second switch. The second terminal is coupled to a first terminal of a third switch. A second terminal of the second switch and second terminal of the third switch are coupled and are further coupled to a low-pass filter. A signal generated by the low-pass filter is inputted into an analog to digital converter, which provides a signal representative of either a signal across the bleeding impedance, or a signal between the battery cell terminals.

Abstract: The invention relates to a method for handling and servicing an electrochemical cell (1), preferably a battery having a number of electrochemical cells (1), comprising a controller (3), in particular a cell controller, preferably a battery controller, at least one sensor (4) connected to the controller (3) for acquiring parameter data (DPar.) of the electrochemical cell (1) or the battery, a storage device (5), which comprises preferably a non-volatile memory, in particular a flash memory, and a unit (2) for data transmission, said method comprising the following steps: (S1) acquiring parameter data (DPar.) of the electrochemical cell (1) or the battery, (S2) feeding the acquired parameter data (DPar.) to the controller (3), (S3) calculating the control data (DStr.) as a function of the supplied parameter data (DPar.) with the controller (3), (S4) feeding the control data (DStr.) to the storage device (5), (S5) reading out the control data (DStr.

Abstract: A deterioration degree calculating apparatus for a secondary battery of the invention includes: obtaining a voltage value at a stop time of charge and discharge of a target secondary battery; obtaining a voltage value at a first start time of charge and discharge after that; obtaining an SOC of the target secondary battery at the stop time or at the start time; obtaining a length of an unused period from the stop time to the start time (an elapsed time); obtaining a self-discharge slope of the target secondary battery by dividing an absolute value of a difference between the voltage value at the start time and the voltage value at the stop time by the elapsed time; obtaining a temperature during an unused period by use of a self-discharge map in which the SOC and the self-discharge slope is recorded for each temperature; calculating a progress degree of deterioration of the target secondary battery during the unused period based on the obtained temperature and elapsed time; and accumulating the calculated det

Abstract: Various aspects of the present disclosure are directed to monitoring battery cells. In accordance with various embodiments, an energy storage cell apparatus includes a current injection circuit that separately inject current into individual ones of a plurality of battery cells that store energy, and an impedance-detection circuit detects an impedance characteristic of each of the plurality of battery cells in response to the injected current. A filter circuit receives impedance data regarding the detected impedance characteristic and separates low-frequency components of the impedance data from high-frequency components of the impedance data. A memory circuit stores data corresponding to high-bandwidth data including both the low-frequency components and the high-frequency components, and an access circuit provides the low-frequency components for the plurality of battery cells to a battery pack controller.

Abstract: The present inventions, in one aspect, are directed to techniques and/or circuitry to determining data which is representative of the state of health, or a change therein, of the battery using the data which is representative of (i) the relaxation time of the battery and/or (ii) the overpotential of the battery. In another aspect the present inventions are directed to techniques and/or circuitry to adapt one or more characteristics of a charge signal using data which is representative of the state of health, or a change therein, of the battery. In yet another aspect the present inventions are directed to techniques and/or circuitry to determine a state of charge of the battery using data which is representative of the state of health, or a change therein, of the battery.

Abstract: A battery system controller is provided which is used for a battery system including a generator, electrical loads, a lead storage battery, a high performance storage battery which has higher-power and higher-energy density, and an opening and closing switch which switches the generator and the lead storage battery, and the high performance storage battery to an electrically conducting state or an interrupted state, a terminal voltage of the high performance storage battery being controlled so as to be lower than a terminal voltage of the lead storage battery. The battery system controller includes a control unit which allows the opening and closing switch to switch from an electrically conducting state to an interrupted state on the condition that charging current flowing to the high performance storage battery is smaller than a determination value, the larger an internal resistance of the lead storage battery, the smaller the determination value is set.

Abstract: A method for managing charging of a rechargeable battery including at least one module including at least one electrochemical cell, the method including estimating a heat flow produced in the at least one module using an observer estimating overall internal resistance of the electrochemical cells of the module.

Abstract: A battery sensing section measures a voltage across a secondary battery. A current sensing section measures a current flowing through the secondary battery. A control section holds the value of an external impedance present in a discharge path outside the secondary battery, discharges the secondary battery from a first time to a second time at which an integrated discharge capacity based on a measured discharge current becomes equal to a predetermined discharge capacity reference value, calculates the internal impedance present in the secondary battery at the second time based on the measured voltage, calculates the second open voltage at the second time by multiplying the sum of the external impedance and the internal impedance by the measured discharge current, and calculates the recovered capacity of the secondary battery based on the first open voltage at the first time, the second open voltage and the discharge capacity reference value.

Abstract: The present invention is directed to an electrochemical cell based on lithium technology, comprising the following components: a positive electrode containing a cathode material, a separator made of an electrically insulating material, a negative a electrode containing an anode material, the electrodes and the separator having layer or sheet form, a liquid and/or solid ion conductor material for transportation of lithium ions between the positive and the negative electrode, the said components being sealed within a casing, wherein the positive and the negative electrode each comprise an electrically conducting structure extending through a wall of the casing for further electrical connection, characterized in that it further comprises: a reference electrode within the said casing which is electrically insulated from the positive and the negative electrode, the reference electrode having layer or sheet form comprising at least one non-metallic lithium compound, and an electrically conducting structure in layer

Abstract: An internal resistance estimation device for estimating an internal resistance of an electric storage device includes a current measurement portion, a voltage measurement portion, and a controller. The current measurement portion is configured to measure a charge current to the electric storage device. The voltage measurement portion is configured to measure a terminal voltage of the electric storage device. The controller is configured to estimate an internal resistance of the electric storage device based on the charge current and the terminal voltage measured in a restrictive period of charge time for charging the electric storage device. The restrictive period is a period in which a time variation in charge current is constant.

Abstract: A system for monitoring parameters of an energy storage system having a multiplicity of individual energy storage cells. A radio frequency identification and sensor unit is connected to each of the individual energy storage cells. The radio frequency identification and sensor unit operates to sense the parameter of each individual energy storage cell and provides radio frequency transmission of the parameters of each individual energy storage cell. A management system monitors the radio frequency transmissions from the radio frequency identification and sensor units for monitoring the parameters of the energy storage system.

Abstract: In a converter of a motor drive control device, one of a first switching element and a second switching element is selected in accordance with a current command value of a current flowing through a reactor. The converter is then controlled so that a drive command for the selected switching element is generated. In this way, the efficiency of the converter is improved while a voltage step-up or step-down operation is performed by the converter.

Abstract: A battery monitoring system utilizes a plurality of transformers interconnected with a battery having a plurality of battery cells. Windings of the transformers are driven with an excitation waveform whereupon signals are responsively detected, which indicate a health of the battery. In one embodiment, excitation windings and sense windings are separately provided for the plurality of transformers such that the excitation waveform is applied to the excitation windings and the signals are detected on the sense windings. In one embodiment, the number of sense windings and/or excitation windings is varied to permit location of underperforming battery cells utilizing a peak voltage detector.

Abstract: The present invention generally relates to a thermal battery testing apparatus and a method for testing a thermal battery. The method includes one or more of the following steps: connecting the thermal battery in series with a resistance; connecting the thermal battery and resistance in series with a sinusoidal voltage source; applying a sinusoidal voltage to the thermal battery, measuring an impedance, reactance and/or capacitance across two terminals of the thermal battery, comparing the measured impedance, reactance and/or capacitance to a reference impedance, reactance and/or capacitance; and indicating whether the tested thermal battery is “in family” or “out of family.” The battery testing apparatus may include a testing device configured to apply a sinusoidal voltage to the thermal battery and to measure the impedance, reactance and/or capacitance across two terminals of the thermal battery. The testing apparatus may further be configured to report “out of family” batteries.

Abstract: A battery condition estimation device estimates a pre-restart voltage drop amount ?Vjh+?Vbn of a battery mounted to a vehicle during period T1 to T2 from initiation of an engine stop until initiation of an engine restart based on detection values regarding the battery condition. The device estimates a voltage drop amount ?Vst during period T3 from initiation of the engine restart until completion of the engine restart based on the detection values regarding the battery condition. The device finally estimates a minimum voltage of the battery during period T1 to T3 from the initiation of the engine stop until the completion of the engine restart based on a voltage detection value Vj0 before the engine stop, the pre-restart voltage drop amount ?Vjh+?Vbn, and the voltage drop amount ?Vst.

Abstract: An internal resistance measurement device for stacked battery includes an AC power supply part for outputting an AC current to an measurement-object, which includes at least a stacked battery made of a plurality of stacked power generating elements, by being connected to the measurement-object, an AC adjusting part for adjusting an AC current so that a positive-electrode AC potential difference, which is a potential difference obtained by subtracting potential in a middle portion from potential in a portion connected to a load device on the positive side of the measurement-object, matches a negative-electrode AC potential difference, which is a potential difference obtained by subtracting potential in the middle portion from potential in a portion connected to the load device on the negative side of the measurement-object, and a resistance calculating part for calculating resistance of the battery based on the adjusted AC current and the AC potential difference.

Abstract: An apparatus is provided to estimate a charged state of a vehicle provided with an internal combustion engine having a crankshaft, a starter that initially rotates the crankshaft when the engine is started, and a battery that powers the starter. The apparatus comprises a detection device and an acquisition device. The detection device detects a voltage of the battery and a discharge current from the battery for a period of time over time instants before and after starting the engine. The acquisition device acquires information indicative of an amount of the discharge current from the battery when the detected voltage of the battery becomes a minimum due to starting the engine.

Abstract: An over-voltage detection and correction system for a transmitter of a mobile terminal that accounts for battery droop during a transmit burst is provided. In general, prior to ramp-up for a first transmit burst, a voltage of the battery of the mobile terminal at a no-load condition is measured. After ramp-up for the transmit burst, the voltage of the battery is measured at full-load, and a current provided to a power amplifier of the transmitter at full-load is detected. Based on the measured voltage of the battery at no-load, the measured voltage of the battery at full-load, and the detected current provided to the power amplifier at full-load, a resistance of the battery is determined. The resistance of the battery is thereafter used to compensate for battery droop during over-voltage detection and correction for one or more subsequent transmit bursts.

Abstract: A method includes the steps of calculating the temperature of a reference point in an electric storage element by using a detected temperature by a temperature sensor attached to an outer face of the electric storage element and a heat conduction equation, and estimating the internal state of the electric storage element by using the calculated temperature of the reference point. The reference point is a lattice point at which a temperature associated with the internal resistance of the electric storage element is shown, out of a plurality of lattice points provided in the electric storage element.

Abstract: Included are embodiments of an ambulatory infusion device. Some embodiments include a battery receiving portion that receives a user-replaceable battery of variable individual characteristics. The user-replaceable battery may serve as a primary power source of the ambulatory infusion device and being successively depleted during application. Similarly, some embodiments include a dosing unit with an electrically powered actuator and an electronic controller that controls operation of the ambulatory infusion device. Still some embodiments include a testing unit that is operatively coupled to the electronic controller, the testing unit being designed to carry out a battery test, the battery test including determining an off-circuit voltage and an internal resistance of the user-replaceable battery. Still some embodiments include an alerting unit that is operatively coupled to the testing unit and/or the electronic controller to provide an alert to a device user in dependence of a battery test result.

Abstract: Battery insulation resistance measurement methods, insulation resistance measurement methods, insulation resistance determination apparatuses, and articles of manufacture are described. According to one aspect, a battery insulation resistance measurement method includes determining a voltage of a battery, determining a voltage of a first terminal of the battery with respect to a ground reference, determining a voltage of a second terminal of the battery with respect to the ground reference, and using the voltages of the battery, the first terminal and the second terminal, determining an insulation resistance of the battery with respect to the ground reference.

Abstract: A diagnosis apparatus performing a diagnosis for reuse of an electric storage apparatus including a plurality of electric storage elements connected electrically in series includes a voltage sensor detecting a voltage of each of a plurality of blocks, the plurality of electric storage elements being divided into the blocks; a current sensor detecting a current in the electric storage apparatus; and a controller calculating an internal resistance of each of the blocks based on outputs from the voltage sensor and the current sensor. The controller specifies the highest of the internal resistances of the plurality of blocks as a criterion to perform the diagnosis for the reuse of the electric storage apparatus.

Abstract: In one embodiment, a method of evaluating a battery module includes: applying a tension load to a test coupon, the test coupon including a segment of a battery terminal connected to a segment of an interconnector busbar; and measuring electrical resistance across the segments of the test coupon. In certain instances, the method further includes applying a different, second tension load to the segments of the test coupon and repeating the measuring of electrical resistance. In certain other instances, the method further includes forming a plot between various values of electrical resistance as a function of various tension loads.

Abstract: It is intended to provide a battery module having a long life by designing such that deterioration proceeds evenly among battery cells. Disclosed is a battery module including a plurality of battery groups being connected in series and each comprising a plurality of battery cells connected in parallel, wherein: a positive electrode terminal and a negative electrode terminal are provided; the battery groups are connected to each other by a plurality of electrically conductive strips; and an electrical resistance value of the conductive strip arranged at a position near a virtual line drawn between the positive electrode terminal and the negative electrode terminal is high, and an electrical resistance value of the conductive strip arranged at a position other than the position near the virtual line is low, the electrical resistance value being measured in a direction of charge and discharge current flow.

Abstract: A battery pack includes: one or two or more secondary batteries; a charge control switch that turns on/off a charging current to the secondary battery; a discharge control switch that turns on/off a discharging current from the secondary battery; a current-detecting element for detecting the charging current and the discharging current; a voltage measuring part that measures the voltage of the secondary battery; a control unit that controls the charge control switch and the discharge control unit; and a storage unit that stores an initial internal resistance of the secondary battery. The control unit measures a closed circuit voltage and a charging current during charging, and a first closed circuit voltage after a first waiting time and a second closed circuit voltage after a second waiting time. The second waiting time is longer than the first waiting time.

Abstract: A method is provided for determining a state variable such as aging of an electrochemical cell comprising an electrode plate group, that includes analyzing at least a portion of a response spectrum of the electrochemical cell to application of an electromagnetic wave in a frequency ranging from 10 kHz to 10 GHz, so as to determine an indicator of the value of the state variable.

Abstract: Systems and methods are provided for monitoring the deterioration of a rechargeable battery. A battery monitoring system may be used to store charging information, discharge information and storage information for a rechargeable battery to a data store. The charging information may include a number of charge cycles incurred by the rechargeable battery. The discharge information may include a number discharge cycles incurred by the rechargeable battery. The storage information may include information relating to periods when the rechargeable battery is not being actively charged or discharged. The battery monitoring system may be further used to determine an amount of deterioration of a battery performance characteristic based on the stored charging information, discharge information and storage information.

Abstract: A method and system for monitoring the health of a battery is provided. A precision frequency can be determined for the battery by applying one of an AC current or voltage perturbation across a frequency sweep with impedance spectroscopy equipment to obtain an impedance response; collecting data related to the impedance response at a plurality of various states of charge within a recommended voltage window of the battery; plotting the collected data on one or more impedance curves; and analyzing the one or more impedance curves at the various states of charge to determine the precision frequency. Next, one of an AC current or voltage perturbation can be applied at the precision frequency resulting in an impedance response. The value of the impedance response can be recorded, and a determination can be made of a battery classification zone that the impedance value falls within.

Abstract: A fuel cell system is configured to have: a voltage superimposing unit that superimposes a predetermined AC signal on an output voltage of a fuel cell; a unit that detects an output voltage value of a battery device, the output voltage value varying as the fuel cell output voltage value on which the AC signal has been superimposed varies; a battery device voltage comparison unit that compares the detected battery device output voltage value with a predetermined threshold voltage; and a measurement permission determination unit that determines whether the AC impedance measurement is permitted or not based on whether or not the battery device output voltage value exceeds the threshold voltage. The fuel cell system can protect the battery device in the impedance measurement of the fuel cell based on an AC impedance method.

Abstract: A voltage detection section 10 comprises an A/D converter section 13 that outputs an A/D detection voltage value (Vad) for batteries 2[i] and voltage level determination sections 16[i] that output a level determination signal, which are the results of comparisons of an analog voltage signal for the batteries 2[i] and a plurality of reference voltages. In the process of the battery voltage increasing or decreasing, the level determination signal changes when the analog voltage signal for the batteries 2[i] exceeds or falls below any of the reference voltages. A level determination voltage value shown by the level determination signal at that change timing and the A/D detection voltage value (Vad) are compared, and an occurrence of an in-range failure is detected when there is a difference between the two.

Abstract: A method of rating a battery includes providing a plurality of numerical values by removing units from standardized ratings or tests for the battery; assigning a pre-calculated unit scaling factor to each numerical value of the plurality of numerical values; and calculating a total rating by multiplying each pre-calculated unit scaling factor by each corresponding numerical value of the plurality of numerical values to obtain a normalized value for each numerical value of the plurality of numerical values, and adding each normalized value.

Abstract: There is provided an impedance measuring system which can accurately measure the impedance of a fuel cell. A motor rotation number detection unit successively detects the rotation number of a motor controlled by an inverter and outputs the detection result to a superposition signal generation unit. The superposition signal generation unit sets the frequency of an impedance measuring signal to a non-resonant frequency so that the control signal of the motor will not resonate with the impedance measuring signal. Thus, by setting the frequency of the impedance measuring signal to the non-resonant frequency, the resonance with the motor is suppressed, which can improve impedance measurement accuracy.

Abstract: A non-contact power transmission apparatus having an AC power source and a resonance system is disclosed. The resonance system has a primary coil connected to the AC power source, a primary side resonance coil, a secondary side resonance coil, a secondary coil, and a load connected to the secondary coil. The primary side resonance coil is separated from the primary coil in an axial direction by a first distance, and the secondary coil is separated from the secondary side resonance coil in the axial direction by a second distance. At least one of the first distance and the second distance is adjusted to be a distance that is determined in advance in accordance with the impedance of the load so that the power transmission efficiency is maintained at a proper value.

Abstract: A battery charger and method for a rechargeable battery pack which includes various elements in series with the cells to be charged, including but not limited to current control FETs, a fuse, current sense resistor, and internal series impedance of the series connected cells to be charged. The charging current Ichg flowing through these series elements reduces the voltage applied to the cells, thus lengthening charging time. A compensation voltage Vcomp, which when added to the nominal charging voltage for the series connected cells overcomes these voltage drops, facilitates more efficient charging while avoiding over-voltage damage to the cells. Three voltages representing substantially all of the voltage drops reducing the charging voltage on the cells, are summed, and the result is a compensation voltage which is utilized to change the nominal charge voltage for the battery to overcome these voltage drops.

Abstract: A converter control unit responds to a command from a start determining unit to control a converter such that a ripple current is generated at a secondary battery. A storage unit stores a map defining a correlative relationship between the temperature and current of the secondary battery and internal resistance. An estimating unit estimates a value of internal resistance of the secondary battery based on each detection value of the temperature and current, and the map stored in the storage unit.

Abstract: Battery insulation resistance measurement methods, insulation resistance measurement methods, insulation resistance determination apparatuses, and articles of manufacture are described. According to one aspect, a battery insulation resistance measurement method includes determining a voltage of a battery, determining a voltage of a first terminal of the battery with respect to a ground reference, determining a voltage of a second terminal of the battery with respect to the ground reference, and using the voltages of the battery, the first terminal and the second terminal, determining an insulation resistance of the battery with respect to the ground reference.

Abstract: There is provided an apparatus that calculates a polarization voltage of a secondary battery. A temperature sensor detects a temperature of the secondary battery; a voltage sensor detects a voltage of the secondary battery; and a current sensor detects an electric current of the secondary battery. A battery ECU calculates a polarization voltage based on the electric current and adaptively sets an upper limit value and a lower limit value of the polarization voltage according to a temperature characteristic of the secondary battery. The calculated polarization voltage is compared with an upper limit value and a lower limit value, whereby the polarization voltage is corrected. An SOC is estimated based on the corrected polarization voltage.