Abstract: An invention is provided for determining a state of health of a battery. The invention includes applying a predefined load profile to a battery, and obtaining a plurality of battery response voltage data corresponding to points along the predefined load profile. The battery electrical double layer capacity data is calculated from the battery response voltage data, and thereafter utilized to determine the state of health of the battery.

Abstract: In an electrical power supply having a plurality of switching power converter circuits and configured to supply a voltage to an electrical load, a method of controlling a duty cycle of at least one switch of one of the plurality of switching power converter circuits includes determining a storage voltage produced by the one of the plurality of energy storage devices. The method further includes determining an average storage voltage corresponding to an average of storage voltages produced by each of the plurality of energy storage devices. The method further includes determining at least one control signal as a function of the storage voltage, the average storage voltage, and a reference voltage. The method further includes controlling the duty cycle of the at least one switch of the one of the plurality of switching power converter circuits based upon the at least one control signal.

Abstract: An electrical apparatus includes a body for consuming power; a battery for supplying power to the body, wherein the body is capable of detecting an installation of the battery into the body, correlating the installation of the battery to a current real-time date, and displaying the date on which the battery was first installed in the body; and a display of a full charge capacity of the battery, the full charge capacity being calculated by comparing an actual present capacity of the battery to an estimated present capacity of the battery.

Abstract: An over voltage transient controller to protect a rechargeable battery from an over voltage transient condition. The over voltage transient controller may comprise a comparator to compare a first signal with a second signal representative of a reference voltage level and to provide an output signal representative of an over voltage transient condition to a switch if the first signal is greater than or equal to the second signal. The switch is responsive to the output signal to protect the rechargeable battery from the over voltage transient condition. The over voltage transient controller may further comprise a DAC, wherein the second signal is based, at least in part, on an output of the DAC. An apparatus comprising a charge switch and such an over voltage transient controller is also provided.

Abstract: A battery safety monitor system. The system includes at least one battery, at least one zener diode, at least one safety device, a microcontroller, a display device and a power supply. The at least one battery comprises at least one cell string capable of outputting voltage signals. The at least one zener diode is operatively coupled to the at least one battery cell string. The at least one safety device is operatively coupled to the at least one battery cell string. The microcontroller is operatively coupled to the at least one zener diode. The display device is operatively coupled to the microcontroller. The power supply is operatively coupled to the microcontroller and the display device.

Abstract: A method for determining a diffusion voltage in an electrochemical cell (e.g., a battery used in connection with an automotive vehicle) includes estimating a previous diffusion voltage, calculating a new diffusion voltage using an equation based on a diffusion circuit model and the previous diffusion voltage, and setting the previous diffusion voltage equal to the new diffusion voltage. The step of calculating the new diffusion voltage may then be repeated.

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

Abstract: Provided is a deterioration determination circuit configuring by including: an SOC detection unit for detecting an SOC of a secondary battery; an internal resistance detection unit for detecting an internal resistance value of the secondary battery; a first determination unit for determining the status of deterioration of the secondary battery based on the internal resistance value detected by the internal resistance detection unit when the SOC detected by the SOC detection unit is within a range of a pre-set first range; a second determination unit for determining the status of deterioration of the secondary battery based on the internal resistance value detected by the internal resistance detection unit when the SOC detected by the SOC detection unit is within a range of a pre-set second range as a range of an SOC, in which a variation of the internal resistance of the second battery in relation to a variation of the SOC of the secondary battery is different from the first range; and a final determination u

Abstract: An automotive vehicle electrical system diagnostic apparatus includes first and second electrical connections configured to electrically couple to an electrical system of an automotive vehicle which includes a battery. Digital samples are obtained during operation of the vehicle which are related to the system. The digital samples are stored in memory.

Abstract: A method for predicting change in an operating state, e.g. state of life, for an electrical energy storage device includes establishing a plurality of values for an operating parameter, e.g. current, of the electrical energy storage device and, for each respective value, determining a corresponding change in the operating state for the energy storage device based upon the respective value. Preferably, change in the state of life is determined based upon an integration of electrical current, a depth of discharge of the energy storage device, and an operating temperature factor of the electrical energy storage device.

Abstract: A method and a corresponding device are described for predicting the power capacity of an electrical energy store, such as a battery in a vehicle, in which, with the aid of a mathematical model for the energy store, its state variables and parameters are continuously adjusted, and thereby a charge and discharge power capability is estimated and predicted.

Abstract: A method for detecting SOC and SOH of a storage battery includes: calculating an SOC value of the storage battery with use of an SOC calculation unit based on a measured voltage value or a measured current value of the storage battery and calculating an SOH value of the storage battery with use of an SOH calculation unit based on the SOC value; further calculating a new SOC value with use of the SOC calculation unit based on the SOH value and calculating a new SOH value with use of the SOH calculation unit based on the new SOC value, these further calculations of SOC value and SOH value being repeated a prescribed n times of at least one so as to obtain an nth calculated SOC value and an nth calculated SOH value; outputting the nth calculated SOH value as an SOH output value and outputting the nth calculated SOH value as an SOC output value; and storing the SOH output value into a memory.

Abstract: A battery tester determines a remaining level of charge of a battery mounted within a separate electronic device having an audio jack. The battery tester includes a plug and a circuit having a high impedance input amplifier. At least one electrical contact of the plug is electrically coupled to an input of the high impedance input amplifier. The plug is removably insertable within the audio jack such that the battery of the separate electronic device is electrically connected to the input of the high impedance input amplifier. When electrically coupled to the battery, an output of the high impedance input amplifier provides a signal proportional to the remaining level of charge of the battery, whereby the remaining level of charge of the battery is obtainable by the battery tester without having to remove the battery from the electronic device.

Abstract: A battery monitoring system (BMS), which utilizes a minimum amount of input data (time, voltage, current, temperature and conductance, for example) to periodically determine a vehicle battery status or condition is provided. The BMS combines electronic hardware and software to give logical and critical data to assess and control a battery-based electrical system. The BMS can include processing circuitry (a microprocessor, for example), which is coupled to a voltage sensor, a current sensor, a temperature sensor, etc., that provide the necessary input data for the microprocessor, which executes program code, to determine the vehicle battery status or condition. A method of monitoring a battery in an operating vehicle is also provided.

Abstract: The present invention is directed to a device, in particular a charger device, with a measuring unit (10) for acquiring at least one battery characteristic value. It is provided that the device includes an arithmetic unit (12) which is provided to determine an ageing-specific charging mode as a function, at the least, of the acquired battery characteristic value.

Abstract: A charge controller of a high temperature battery for a power compensator of an electric power transmission line. The charge controller includes a sensor and a processor including a memory module. The charge controller includes a virtual battery model of the battery.

Abstract: It is aimed at stably implementing a protection function of a secondary battery mainly under software control and providing a battery pack characterized by a reduced circuit installation area, parts costs, and power consumption. An AD converter outputs a voltage value between a positive electrode and a negative electrode of a secondary battery. Based on the voltage value, a microcontroller determines a state of the secondary battery out of overcharge, normal operation, and over-discharge states. According to the determined state, the microcontroller controls operations of a discharge current cutoff means and a charge current cutoff means via a FET driver. When it is determined that the secondary battery is placed in an overcurrent state based on the charge and discharge current size of the secondary battery, an overcurrent detection circuit enables the discharge current cutoff means to be a cutoff state in preference to control by the microcontroller.

Abstract: In accordance with various embodiments, there are systems and methods for predicting end of life of a Li-ion battery. The method can include at least one of partially charging and partially discharging a battery, measuring an open circuit voltage of the battery before and after at least one of partial charging and partial discharging, and determining a state of charge value of the battery corresponding to the open circuit voltage measured before and after at least one of partial charging and partial discharging. The method can also include correlating at least one of a charge energy and a discharge energy with a change in the state of charge value and extrapolating to get a full battery capacity, tracking the full battery capacity as a function of time, and performing trend analysis of the full battery capacity over time to predict the battery's end of life.

Abstract: An electric quantity indicator for an electromotive vehicle comprises an electric measuring wire parallel connected to a battery; a feedback circuit connected between a motor of the power supply load and the electric measuring wire; and a meter responsed to the quantity of electricity of the electric measuring wire. The meter is an electronic display panel, and the feedback circuit and the electric measuring wire are installed with analog to digital (A/D) converter for address dividing the value in a memory, in which this value is displayed in the aforesaid meter. Thereby, as a load is actuated and power is consumed, the feedback circuit will detect, and the electric measuring wire will conduct, a real value about the power stored in the battery is displayed on the meter so as to be viewed by a user. Therefore, the condition that due to an error of electric quantity, the user can not know the real the electric quantity and thus the car is stopped owing to exhaustion of electric power is avoided.

Abstract: A refresh control system that selectively initiates a refresh charge cycle includes an energy storage device and an electric machine that is operable to charge the energy storage device. A control module monitors a usage period of the energy storage device and determines a bias factor. The control module determines a modified usage period threshold based on a usage period threshold and the bias factor. The control module regulates the electric machine to initiate a refresh charge cycle of the energy storage device when the usage period exceeds the modified usage period threshold.

Abstract: A high frequency battery charger for charging a target battery is provided. The battery charger includes a charging circuit including a high frequency transformer, a switch switching the high frequency transformer, a filter coupled to the high frequency transformer for passing a DC voltage signal and a controller providing a high frequency driving signal to the switch. Measuring circuitry measures at least one of a voltage or a current at the target battery. A microprocessor receives the measured voltage or current and calculates diagnostics of the target battery based on at least one of the measured voltage or current.

Abstract: A method and system for measuring the remaining capacity of a battery with open circuit voltage detection is disclosed. The method includes the steps of measuring an open circuit voltage, obtaining an initial capacity based on the open circuit voltage, initializing an accumulation counter with the initial capacity, adjusting the accumulation counter, and obtaining the remaining capacity based on the accumulation counter. The method further includes the step of calibrating the accumulation counter to eliminate accumulated error and offset resulting from the previous operation of adjusting the accumulation counter.

Abstract: A sensor array for detecting the state of a battery which is situated in the proximity of the pole terminals of the battery for detecting the electrical state variables of the battery. In addition to a measuring path, an electronic circuit is also integrated into the sensor array whose supply voltage is taken directly from the battery, the supply voltage being connected to the electronic circuit via a cutout in such a way that the cutout is integrally joined into the lead of the supply voltage in the housing of the sensor array.

Abstract: A method and device for determining the charge of a battery, characterized in that a gain crossover frequency (f±) for an impedance of the battery excited by an alternating current signal is established, and the gain crossover frequency (f±) is assigned to the charge of the battery, whereby the gain crossover frequency (f±) is a frequency of the alternating current signal at which an imaginary portion of the impedance of the battery vanishes.

Abstract: A method and apparatus that allows for controlling operating time of a portable computer system and a peripheral device. A portable computing system that includes a rechargeable power supply and that includes a connection mechanism for coupling to a peripheral device is used to control operating time of the portable computer system and the peripheral device. In one embodiment, a user can choose between maximizing the operating time of the portable computer, maximizing the operating time of the peripheral device, or maximizing the life of the entire system (maximizing the operating time of the portable computer system and the peripheral device). When operating time of the portable computer system is to be maximized, power is sent from the peripheral device to the portable computer system to extend the operating time of the portable computer system.

Abstract: The present invention is a battery fuel gauge circuit for measuring the capacity of a battery pack. The battery fuel gauge circuit includes an amplifier circuit, a correction circuit, a plurality of comparators, and a multiplexer. The amplifier circuit can sense a discharge current flowing through a sense resistor and a variable temperature from the battery pack and generate a first and a second voltage signals, which are corrected by the correction circuit and compared with a reference voltage by the plurality of comparators. After correction and comparison, the multiplexer can transmit the compared signals to an external indicating circuit that controls the display of the capacity of the battery pack.

Abstract: The present invention relates to an implementation of a method for cell equalization. The present invention uses other information such as the individual cell state-of-charge (SOC) estimates, and individual capacities and/or cell Coulombic efficiencies, possibly available from a dual extended Kalman filter. The present invention defines or refers to an operational SOC range between a minimum and a maximum. The minimum and maximum could be constants or could be dynamic based on functions of other variables. SOC can be measured relative to maximum charge or relative to maximum discharge for each cell. When the SOC is not consistent across the cells, a prioritizing scheme is used to determine which cells require equalization.

Abstract: The method for calculating charged rate of a secondary battery is intended to calculate charged rate of a secondary battery which supplies electric power to loads, and comprises the step to measure voltage of the secondary battery more than once in a predetermined period of time after termination of charge or discharge, the step to determine the coefficients of a quadric or more exponential damping function which approximates the time characteristic of the open circuit voltage of the secondary battery by recursive calculation with the plural measured voltage values, and the step to calculate a convergent value of the open circuit voltage of the secondary battery from at least the exponential damping function with the coefficients determined above. Therefore, precise charged rate of the secondary battery can be calculated from the precise convergent value of the open circuit voltage.

Abstract: Disclosed is a method of estimating a maximum output of a battery for a hybrid electric vehicle (HEV). The method comprises extracting maximum charge/discharge outputs of the battery depending on a plurality of charged states (SOC) of the battery under which the vehicle is able to be driven and calculating an interrelation between them; extracting maximum charge/discharge outputs of the battery at plural temperatures under which the vehicle is able to be driven, and calculating an interrelation between them; extracting degradations of outputs of the battery as a capacity of the battery is discharged during the traveling, and calculating an interrelation between them; and based on the interrelations obtained, estimating a maximum output of the battery using a function.

Abstract: An electronic apparatus has a multiplicity of display units including an electronic viewfinder and a liquid crystal display (LCD) panel. The apparatus has various display modes. The remaining battery power, i.e., estimated amounts of remaining battery times relative to a current remaining battery capacity, are calculated for the respective display modes. The calculated remaining battery power is collectively displayed as the remaining battery power information on the respective display units. The remaining battery power can be obtained for all the display modes even when the battery is being charged, so that a user can always grasp the remaining battery power of any of the display modes.

Abstract: A lead acid battery model suitable for programming on a motor vehicle body computer uses environmental and target battery operating variables for maintaining synchronization of the model with the target battery under actual operating conditions. The model includes a energy flow section with at least two integrators for simulating primary and recovery reservoirs of charge in the battery. An output voltage estimation signal provides a signal for comparison with measured battery voltage for synchronization. Capacity of the reservoirs is generated from manufacturer specifications measured against battery performance.

Abstract: A system and method for charging and thus extending the life of an electrical storage device is disclosed. The system provides for developing an essentialized cell model structure of the electrical storage device; determining model parameters for charge-discharge data of the structure; and determining charge-discharge behavior of the structure in a voltage-charge plane. The method also includes measuring voltage values of the structure based upon the charge-discharge behavior; and deriving an instantaneous damage rate from the measured voltage values. The method further includes developing a charging profile based upon the instantaneous damage rate, wherein the charging profile optimizes a charging current with respect to the damage per cycle so as to extend the overall life of the electrical storage device. The method also includes the ability of the system to track the parameters of the electrical storage device as the device changes with time.

Abstract: An available input-output power estimating device for a secondary battery includes a parameter estimating section substituting a measured current value I and a measured voltage value V into an adaptive digital filter using an equivalent circuit model of the secondary battery for thereby collectively estimating values of parameters in the equivalent circuit model, an open circuit voltage calculator substituting I, V, and the estimated parameter values into the equivalent circuit model for calculating an open circuit voltage {circumflex over (V)}0, an available input power estimating section estimating an available input power Pin of the secondary battery using components (ân,{circumflex over (b)}n), associated with a direct term in the equivalent circuit model, in the estimated parameters, the open circuit voltage estimate value {circumflex over (V)}0 and an upper limit voltage Vmax of the terminal voltage, and an available output power estimating section estimating an available output power Pout for the secon

Abstract: When surplus power not charged to an electric storage is generated at the time of regenerative braking of a vehicle, a voltage is generated across first and second neutral points using a zero-voltage vector each of first and second inverters and the generated surplus power is consumed by a resistance connected across the first and second neutral points. The voltage generated across the first and second neutral points is calculated in accordance with the surplus voltage, using a resistance value of the resistance.

Abstract: At least one of continuous disconnection, intermittent disconnection, and temporary disconnection, of wireless communication between the input device and the game apparatus is detected. Remaining battery amount data representing a remaining battery amount of the input device is obtained via the wireless communication. It is determined that the power of the input device is insufficient based on that the wireless communication is detected to be disconnected and that the obtained remaining battery amount data represents a remaining battery amount of a predetermined level or lower. When it is determined that the power is insufficient, the power insufficiency is notified.

Abstract: Data indicating a relationship of life of a battery to a value of load power applied to the battery in discharge and environmental temperature of a place where the battery is installed are prepared beforehand. Next, the load power and the environmental temperature when the battery is discharged are measured, and then a life value corresponding to these measured values is selected from the data so as to be set as an expected life value. Next, a first life reduction amount is calculated from a natural logarithmic function with the number-of-discharges as a variable, and the difference between the expected life value and the first life reduction amount is set to a remaining life value, on the basis of which the life of the nickel-hydride battery is determined. By this method, the life of the nickel-hydride battery as a backup power source can be accurately determined, while correction based on phenomena unique to the nickel-hydride battery is performed.

Abstract: In accordance with various embodiments, there is a method for determining the capacity of a battery. Various embodiments include applying a predetermined current ramp to a fully charged lead-acid battery while measuring a battery terminal voltage. An Iup can be determined, where the Iup is a transition from charging to overcharging. A specific gravity of the lead-acid battery can also be determined. The capacity of the lead-acid battery can then be determined from the Iup using a correlation function that describes the relationship of the Iup to the capacity, where the correlation function depends on the specific gravity of the lead-acid battery.

Abstract: Disclosed is a method for structuring a comparative reference value used to estimate a residual charge (SOC; State of Charge) of a battery.

Abstract: A remaining capacity calculation method for a secondary battery and a battery pack are provided. Dischargeable electric power is accurately calculated and accuracy of a remaining capacity rate found by an electric power integration method may be improved by providing a remaining capacity calculation method for a secondary battery. The method includes calculating a consumed electric power by way of integration of voltage and current measured at a preset time interval when using the secondary battery; calculating an available dischargeable electric power by subtracting an energy loss and unavailable energy from a discharge electric power of the secondary battery; and calculating a remaining capacity rate from a ratio between the calculated electric power and the dischargeable electric power.

Abstract: Data indicating a relationship of life of a battery to a value of load power applied to the battery in discharge and environmental temperature of a place where the battery is installed are prepared beforehand. Next, the load power and the environmental temperature when the battery is discharged are measured, and then a life value corresponding to these measured values is selected from the data so as to be set as an expected life value. Next, a first life reduction amount is calculated from a natural logarithmic function with the number-of-discharges as a variable, and the difference between the expected life value and the first life reduction amount is set to a remaining life value, on the basis of which the life of the nickel-hydride battery is determined. By this method, the life of the nickel-hydride battery as a backup power source can be accurately determined, while correction based on phenomena unique to the nickel-hydride battery is performed.

Abstract: A hybrid electric vehicle has an energy storage system including one or more batteries. Battery service life is managed by establishing an amp-hour throughput budget and limiting battery current substantially to the budget.

Abstract: In accordance with various embodiments, there is a method for determining the state of charge of a battery. Various embodiments include the steps of determining the specific gravity of the battery and measuring an open circuit voltage of the battery at rest. The open circuit voltage at rest can be used to determine the battery state of charge from a correlation function dependent on the battery specific gravity.

Abstract: A diagnosis method for SOH of batteries includes the steps of: providing data of discharge voltages and currents of a battery unit; setting an acceptable value of a predetermined period of time and an acceptable range of variation rate of discharge current for the battery unit; calculating variation rates of discharge voltages and currents of the battery unit within the predetermined period of time by using the data of discharge voltages and currents; recording the data of discharge voltages and currents of the batteries and variation rates thereof; comparing the data of discharge voltages of the batteries and the variation rates thereof if the variation rates of discharge current are fallen within the acceptable range of current variation with selected reference data; and converting results of compared data of discharge voltages of the battery unit and the variation rates thereof into a SOH index.

Abstract: Reactive replenishable device management comprises receiving device measurement data from at least one device, updating one or more device usage profiles associated with the at least one device, and if an analysis of the one or more device usage profiles indicates usage of the at least one device is sub-optimal, performing one or more of: controlling at least one of an attribute or an operation of the at least one device, issuing one or more device management recommendations to a user of the at least one device, and issuing one or more user alerts to the user. The at least one device comprises at least one of one or more replenishable devices, one or more replenishers associated with the one or more replenishable devices, and one or more other devices associated with the one or more replenishable devices.

Abstract: A method for terminating battery discharge to avoid battery damage and maximize battery usage includes the steps of: (a) determining battery capacity; (b) storing a capacity result of the capacity determining; (c) determining battery voltage; (d) during a monitored battery operation, integrating battery current flow over a time interval to determine an integrated charge value at an end-of-interval-time; (e) determining an extant depth of discharge at the end-of-interval-time; (f) if the extant depth of discharge is neither within a first range of a maximum depth of discharge nor the battery voltage is within a second range of a minimum battery voltage, carrying out steps (d) through (f); (h) if the extant depth of discharge is within the first range of the maximum depth of discharge or if the battery voltage is within the second range of the minimum battery voltage, terminating the monitored battery operation.

Abstract: A battery ECU estimates the SOC by integrating the battery current measured by a current sensor, and the battery voltage Vnis measured by a voltage sensor, and the battery temperature Tnis measured by a thermometer if the fluctuation of the charging/discharging current is great. If the number m of estimations of SOCnis m?10, m is incremented. The battery internal resistance Rnis estimated from the measured battery temperature Tnby using a correlation map showing the correlation between the previously stored battery temperature T and the battery internal resistance R. An estimation charging/discharging current Inis determined using the measured battery voltage Vn,the battery open voltage Vocvn-1determined on the basis of the previously estimated charged state, and the estimated battery internal resistance Rn. The SOCnis estimated by integrating the estimated charging/discharging current In. If the number m of estimations of the SOCnis m=10, the number m of estimations is changed to 0.

Abstract: This system provides a method for determining whether ordinary battery cells, a battery pack, and/or a charger unit are attached to a portable electronic device. The system provides a center contact in a battery shaft that contacts a battery pack or a point on an individual battery and allows the device regulation unit to measure the voltage at that point. If the voltage is below a particular threshold, then the system determines that a battery pack may be inserted in the battery shaft and the portable electronic unit enters a battery pack mode. If the voltage is above the threshold voltage, then the portable electronic device enters the battery operation mode. If a voltage transition is sensed on the DEVICE START line, the portable electronic device determines that the charger is installed and the portable electronic device enters the appropriate mode.

Abstract: If the capacity variation is greater than a pre-stored value, the SOC converted from Qmin sometimes cannot recover to a control center value. In such a case, inconveniences including the continuation of an event where the HVECU cannot output a command to stop the charging are prevented by computing an apparatus SOC and reporting the SOC to the HVECU. The apparent SOC is computed by increasing the value of SOC in accordance with the magnitude of the capacity variation. The thus-computed apparent SOC is reported to the HVECU by the battery ECU, so that it can be determined that the control center value has been exceeded. Thus, it becomes possible to provide battery control apparatus, method and program and a battery control system for a battery pack which are capable of controlling the charging/discharging of the battery pack with an improved accuracy despite capacity variation.

Abstract: Data indicating a relationship of life of a battery to a value of load power applied to the battery in discharge and environmental temperature of a place where the battery is installed are prepared beforehand. Next, the load power and the environmental temperature when the battery is discharged are measured, and then a life value corresponding to these measured values is selected from the data so as to be set as an expected life value. Next, a first life reduction amount is calculated from a natural logarithmic function with the number-of-discharges as a variable, and the difference between the expected life value and the first life reduction amount is set to a remaining life value, on the basis of which the life of the nickel-hydride battery is determined. By this method, the life of the nickel-hydride battery as a backup power source can be accurately determined, while correction based on phenomena unique to the nickel-hydride battery is performed.

Abstract: A multi-battery charging system for reduced fuel consumption and emissions for an automotive vehicle. The system starts the vehicle with a start battery in a fuel savings manner, removing electrical torque from the alternator shaft, and allows a second (run) battery to provide all or some of the current required by the vehicle loads as a fuel savings measure. The system also utilizes an electrically heated catalytic converter (EHC) and a third (EHC or storage) battery to provide a 3 to 15 second preheat and/or a 20 second current, during vehicle start, to the EHC heater coil, e.g., of a small EHC located in series with a standard catalytic converter for emissions reduction to reduce emissions during start. The start battery is recharged after start and switched out of the system fully charged for future vehicle starts.