Abstract: A method for controlling a vehicular electric system having multiple power sources including an engine-driven generator. The power sources for supplying power to charge an onboard battery are determined based on difference between the power generation cost of each power source and that for generating an amount of power charged in the battery. Furthermore, amounts power to be supplied to the battery 103 for charge is determined based on the amount of power currently charged in the battery.

Abstract: A method for providing an elective replacement indicator (ERI) voltage for a first implantable electrochemical cell, comprising the steps of providing a second, substantially identical exemplary electrochemical cell; repeatedly connecting and disconnecting the second cell to a sequence of at least three loads, thereby discharging the second cell from a state of about zero percent to at least about ninety percent depth-of-discharge; generating cell voltage vs.

Abstract: A Battery Management System (BMS) and a battery management method include a sensing unit to measure a battery terminal voltage, current, and temperature, and a Main Control Unit (MCU) to compare the measured battery terminal voltage, current, and temperature to a State of Charge (SOC) reset condition and to reset a battery estimate SOC according to the comparison result. The MCU resets the battery estimate SOC to a first reset SOC when the SOC reset condition corresponds to a first SOC and reset the battery estimate SOC at a second reset SOC when the SOC reset condition corresponds to a second SOC.

Abstract: A method for charging a secondary battery with a constant current, in which a peak of output voltage is detected by utilizing a predetermined current value, and then the battery continues to be charged with a current value lower than the predetermined current value, so that the peak of output voltage or a voltage drop subsequent to the peak is detected, or alternatively a timer may be used, for termination of the charging operation.

Abstract: One embodiment relates to a method of pre-set discharging of a battery in a portable device which is connected to external power. The battery is charged until a fully-charged level is reached, and the time at the fully-charged level is tracked. The charging of the battery is halted after a maximum full-charge time period is elapsed. The charging is restarted after a pre-set charge level is reached. Other embodiments are also disclosed.

Abstract: A control device for a motor-driven vehicle, the control device includes: a zone determining unit that determines at least a normal use zone, a discharge zone, an over-discharge zone, a charge zone, and an over-charge zone; and a control unit controlling the motor by stipulating the charge and discharge power of the storage unit for each zone that is determined by the zone determining unit, setting the normal use zone to be in a predetermined range that includes a remaining capacity at which the discharge output according to the remaining capacity of the storage unit and the charge input according to the remaining capacity of the storage unit are equivalent, and making the discharge output and the charge input in the normal use zone to be a predetermined value regardless of the remaining capacity of the storage unit in the zone.

Abstract: In one implementation, a method for charging a battery system is provided. The method includes enabling determining if a charger is coupled to a battery system, the battery system including one or more cells and a charge enable transistor. The method also includes enabling determining if a voltage level of the cells is less than a predetermined first low voltage level. If the voltage level of the cells is less than the predetermined first low voltage level, enabling charging of the cells at a reduced rate including adjusting a voltage applied to the charge transistor gate terminal to regulate a voltage seen by the charger to a level that is less than a predetermined second voltage level. Additionally, when the voltage of the cells reaches the predetermined first low voltage level, the method includes substantially fully enabling the charge transistor to allow for charging at full rate by the charger.

Abstract: In a voltage detecting apparatus, a voltage controlled oscillator, when an input voltage is applied thereto, outputs a signal with a logical value that is periodically inverted. A detector counts a number of logical inversion of the output signal from the voltage controlled oscillator over an interval between edges of pulses of a pulse signal to thereby generate, based on the counted number of logical inversion, digital data as a detected result of the input voltage. A determiner determines whether a reduction of a time required to detect the input voltage is higher in priority than an increase of a resolution of detection of the input voltage. A variably setting unit variably sets a frequency of the pulse signal based on a result of the determination of whether the reduction of the time required to detect the input voltage is higher in priority than the increase of the resolution of detection of the input voltage.

Abstract: A method for operating a battery having a plurality of battery cells includes determining when certain end of life criteria for the battery are met. A counter is incremented when the certain end of life criteria are met. The battery is rebalanced when it is determined that the end of life criteria are met, and the counter is not greater than a predetermined value. An end of life of the battery is indicated when it is determined that the end of life criteria are met, and the counter is greater than the predetermined value.

Abstract: A rechargeable battery controller for controlling output of a rechargeable battery mounted on a vehicle having a power source including an internal combustion engine, a starter motor for starting the internal combustion engine, and a vehicle controller. The rechargeable battery controller includes a control circuit for setting an upper limit for discharge power output by the rechargeable battery in a set period of time and providing the upper limit to the vehicle controller. The control circuit is programmed to reset the upper limit to a value greater than or equal to a power value required to drive the starter motor when a first requirement in which power supply from the rechargeable battery to the starter motor is scheduled and a second requirement in which the upper limit is less than the power value required to drive the starter motor are both satisfied.

Abstract: A quantum generator and related devices of energy extraction and conversion based upon the interaction of light and matter using a constructive arrangement of at least two metallic reservoirs with high ratios between the surface area and the mass of metal from which the metallic reservoirs are formed. The at least two metallic reservoirs are submitted to tension and compression states creating thermo potentials on the free electron gas. In one embodiment, a quantum capacitor is formed by at least two porous plates between pairs of batteries that are submitted to tension and compression states.

Abstract: The electrochemical regeneration of lead battery cells during which, after the treatment of the battery by some of the regeneration additives on the basis of an aqueous solution of hydrogen peroxide and after the basic charging, they are alternately or intermittently charged and discharged. Above the limit located above the level of the full charge it is charged with a current of 1.1%-4% and discharged with a current of 0%-5% related to the nominal value of the capacity of the cell or storage battery, or else the charging is carried out in two phases or by a constant current. Under the limit located below the level of the permitted discharging it is discharged with a current of 1% to 4% and subsequently charged with a current of 3%-10% related to the value of the capacity of the battery to a decrease in the voltage to 1.6 V of the cell or any of the battery's cells. Then the battery supplies 10%-15% of its nominal capacity and this entire procedure is repeated 2-5 times.

Abstract: A high frequency battery charger includes a converter, drive logic, and control logic. The converter transforms a DC voltage into a high frequency AC voltage. The drive logic controls a conversion of the high frequency AC voltage through a train of pulses. The control logic adjusts the output of the converter to maximize a charging cycle of a battery. The method of transforming an AC input into a direct current output used to charge a rechargeable battery includes transforming an AC input into a first DC output; transforming the first DC output into a high frequency AC output; transforming the high frequency AC output into a second DC output; and passing a charging current to an external load when the load is correctly connected to an output.

Abstract: To reduce calculation errors of remaining batter power so as to take into account capacity diminutions due to cycle degradation and temperature, a remaining power calculation device specifies a temperature correction value for calculation of remaining battery power corresponding to temperature, from among temperature correction values changed every predetermined number of charge/discharge cycles stored in a correction value storage device, on the basis of a temperature of a battery cell measured by a temperature measurement device and the number of charge/discharge cycles counted by a charge/discharge counting device, and calculates remaining battery power corresponding to the specified temperature correction value.

Abstract: A charging and discharging control circuit controls charging and discharging of a secondary battery by monitoring at least one of a voltage across, and an electric current through, the secondary battery and controlling a switching circuit in a charging and discharging pathway of the secondary battery. A charging and discharging switch control circuit controls the switching circuit. A driver circuit outputs a signal from the charging and discharging switch control circuit to the switching circuit through an output terminal. A logic circuit compares a voltage of the signal from the driver circuit with a voltage applied to the output terminal from an external portion. The charging and discharging control circuit is switched between a normal operating state and a testing state in accordance with a result of the comparison by the logic circuit.

Abstract: An HV-ECU executes refresh-discharging of a battery before the battery is charged from a commercial power source using an AC/DC converter. After the battery is refresh-discharged, the HV-ECU outputs a control signal to the AC/DC converter such that the battery is charged from the commercial power source by the drive of the AC/DC converter.

Abstract: A high state of charge results in reduced ageing and less wear of and to a rechargeable battery. Furthermore, acid stratification occurs in rechargeable batteries, primarily as a result of the influence of the force of gravity on the electrolyte, leading to a significant reduction in the performance of the rechargeable battery. The subject matter of the invention describes a method and an arrangement for varying the state of charge and state of health of rechargeable batteries, in which a separate electric current (i) is applied individually to at least one cell (Z) in the multicell rechargeable battery (1), this current (i) being superimposed on a working current (iA), and with this current (i) acting on this at least one cell (Z) in order to charge or discharge this cell (Z).

Abstract: A battery remaining capacity detection method calculates a remaining capacity of a battery having the possibility that a memory effect occurs by using correlation between an voltage V0 and the remaining capacity. Correlation between a reset voltage Vo reset that is obtained by subtracting a value obtained by multiplying an occurrence amount Vm based on the memory effect by a memory effect occurrence amount correction value C(SOC) from an initial voltage Vo ini and the remaining capacity is obtained, in the battery after use, based on correlation between the initial voltage Vo ini and the remaining capacity. The remaining capacity is obtained by setting the voltage V0 of the battery after use as the reset voltage V0 reset. This method provides precise battery detection without completely discharging.

Abstract: In one embodiment, a battery charger is configured to provide a normal charge current during a first time period and to supply a maintenance current after the first time period expires.

Abstract: A battery control module for a battery system comprises a voltage measuring module that measures battery voltage and a current measuring module that measures battery current. A state of charge (SOC) module that communicates with the current and voltage measuring modules and that estimates SOC based on relaxation voltage.

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: Circuitry for charging a battery includes a switch for coupling the power source to the battery. The switch is turned on and off in accordance with a periodic control signal including a plurality of periods. Each period includes a first duration during which the control signal is in a first state and a second duration during which the control signal is in a second state. The switch is turned on when the control signal is in the first state to couple the power source to the battery, and turned off when the control signal is in the second state to decouple the power source from the battery. Since the switch is periodically turned off while the battery is being charged, the average amount of heat generated by the switch is reduced, thereby preventing excessive thermal emission from the battery charging circuitry.

Abstract: A method and system for modeling or simulating an application environment so as to evaluate the effect of a selected battery and charger in the application environment. Sensors are used to gather data regarding the energy consumption needs of the application environment over time. Based on the energy needs and/or user-specified application environment parameters, such as a charge schedule, a battery size and type, and a charge return model, an energy transfer profile for the application environment is generated and outputted. The energy transfer profile provides an indication of the state of charge of the battery over time based upon the simulated discharging and charging of the battery in the application environment. The generation of the energy transfer profile takes into account the charging schedule and the incremental change in battery parameters over time.

Abstract: The present invention provides a system and method for operating a rechargeable battery, the system comprising: current maintaining device for maintaining a predetermined current to the rechargeable battery until the rechargeable battery reaches a predetermined maximum voltage; voltage maintaining device for maintaining a predetermined voltage to the rechargeable battery until a predetermined minimum current is delivered to the rechargeable battery; determining device for determining a cyclical charge value delivered to the rechargeable battery by the current maintaining device and the voltage maintaining device during a cycle; and a correction device for correcting the determining device when charge is not being delivered to the rechargeable battery, on the basis of the charge value.

Abstract: The control apparatus-integrated generator-motor has: a generator-motor; and a control apparatus that is constituted by an inverter, a control circuit, a temperature sensor, etc. The control circuit determines whether or not switching element temperature will exceed the maximum permissible temperature when a command for an automatic engine stopping operation is issued. Then, if it is determined that the maximum permissible temperature will be exceeded, generated output of the generator-motor is reduced immediately before the automatic engine stopping operation in such a way that the switching element temperature will not exceed the maximum permissible temperature. The engine is subsequently stopped automatically.

Abstract: A pulse charger perform fine control of a charging current according to a battery voltage. The pulse charger includes a switch that turns a charging current from an external power supply on and off. A current detector detects charging current using a current detection resistor. An averaging section averages the output of the current detector. A reference voltage generator generates a reference signal. A comparison section compares an output voltage from the averaging section with the reference signal. A controller controls the switch section based on the output of comparison section. The comparison section includes a comparator that has a hysteresis width. The comparison section outputs an inverse signal between reference voltage and the hysteresis width. The controller performs on/off control of the switch section based on an inverse signal from the comparator and sets an average value of the charging current to a target constant value.

Abstract: A battery charger includes current sources for generating first and second currents respectively, a current sensor, a current source controller, and a reference voltage generator. The first current charges a battery in a first current path, and the second current is conducted to a feedback load in a second current path separate from the first current path. The current sources form a current mirror and are controlled by the current source controller from comparing a reference voltage with a terminal voltage of the feedback load. The current sensor indicates a level of the first current to the reference voltage generator that sets the reference voltage such that the first current is maintained to be constant.

Abstract: On-premises pager loss is reduced by alerting patrons they are out of range. Pagers include an LCD with messages or promotions. An LED on the pager emits different colors indicating the level of battery charge. Circuitry in the pager causes a higher charge to be delivered to the battery when the pager is first coupled to a charging unit, and a lower charge to be delivered thereafter. Stacked slots in the charging unit receive the pagers. This permits access without disconnection of pagers in other slots and removal from the slots using first-in-first-out rotation. Charging rails on the charging unit simultaneously and directly connect each pager in the slots. Charging units are electrically coupled to other units in a daisy chain. A light on the unit indicates whether it is receiving power. Conductors on the pagers mechanically interlock with the charging rail when a pager is inserted into a slot.

Abstract: A method for charging a lead acid storage battery to advantageously extend its life is described. The termination of a charging process is based upon an evaluation of the first derivative (dv/dt) and second derivative (d2v/dt2) of the applied charging voltage. By utilizing the first derivative (dv/dt) and second derivative (d2v/dt2) as charging criteria, an amount of overcharge is applied to the battery that takes into account the precise amount of amp-hours previously removed from the battery. A charger arrangement for performing a charging process of the invention also is described.

Abstract: An electronic device (e.g., computer system, etc.) employing dynamic power management of the present invention adjusts power consumption in accordance with an analysis of parameters and events occurring over one or more time-periods. Preferably, the electronic device monitors microprocessor, operating system, peripheral and/or device-level events and adjusts run-time parameters, such as microprocessor clock frequency and voltage, to reduce power consumption with minimal perceived degradation in performance.

Abstract: A monitoring circuit for accurately monitoring a voltage level from each of a plurality of battery cells of a battery pack includes an analog to digital converter (ADC) and a processor. The ADC is configured to accept an analog voltage signal from each of the plurality of battery cells and convert each analog voltage signal to a digital signal representative of an accurate voltage level of each battery cell. The processor receives such signals and provides a safety alert signal based on at least one of the signals. The ADC resolution may be adjustable. A balancing circuit provides a balancing signal if at least two of the digital signals indicate a voltage difference between two cells is greater than a battery cell balance threshold. An electronic device including such monitoring and balancing circuits is also provided. Various methods are also provided.

Abstract: A discharging circuit, connected to both terminals of a lithium battery, includes a first discharge resistor, a second discharge resistor, and a transistor for occasionally discharging the lithium battery to reduce the SOC difference among respective lithium batteries constituting a combination battery. A voltage detecting circuit detects a terminal voltage of the lithium battery via the first discharge resistor. A discharge controller judges a failure occurring in the discharging circuit based on a comparison between a terminal voltage value detected when the transistor is turned on and a terminal voltage value detected when the transistor is turned off.

Abstract: Method of determining the state of charge soc of a battery, in particular a starting battery of a motor vehicle; the state of charge being calculated, in a first operating range, on the basis of a model calculation in which a measured and a calculated battery voltage UBatt, UBatt, are balanced, using feedback.

Abstract: A method and apparatus are provided to calculate capacitance remaining on a power source in a battery powered device. A database is provided to store data associated with past battery performance data and data associated with a battery operating the device. The battery data includes battery drainage factors associated with the battery make and model, and the percent of time the apparatus has historically operated in a particular status. An algorithm is provided utilizing current and past data associated with the power source and the associated device to calculate time remaining for operation of the device with the current power source.

Abstract: A method for controlling the charging and discharging phases of a backup capacitor for a data storage medium has the step where the backup capacitor is first discharged to a defined voltage level before it is charged. The capacitor is discharged using a constant current. This ensures that the charging current for the backup capacitor cannot be used to identify what the charge-state of the capacitor was before discharging. Therefore, it is no longer possible to infer the currents that flowed during security-related arithmetic operations in a data processing unit. In one advantageous circuit configuration, a constant current source is formed by a current-mirror circuit, and a comparator is used to compare the voltage on the backup capacitor with a bandgap reference.

Abstract: Method for treatment, in the form of regeneration, of accumulators having at least one cell, preferably lead batteries, in which a varying direct voltage from a charging unit is applied in intermittent current supply periods, which are interrupted by current free pauses, the direct voltage being sufficient to generate gas in the accumulator. During the treatment process, process data is registered, for at least one cell in the accumulator, which process data is used in order to control the treatment process.

Abstract: A monitoring circuit for accurately monitoring a voltage level from each of a plurality of battery cells of a battery pack includes an analog to digital converter (ADC) and a processor. The ADC is configured to accept an analog voltage signal from each of the plurality of battery cells and convert each analog voltage signal to a digital signal representative of an accurate voltage level of each battery cell. The processor receives such signals and provides a safety alert signal based on at least one of the signals. The ADC resolution may be adjustable. A balancing circuit provides a balancing signal if at least two of the digital signals indicate a voltage difference between two cells is greater than a battery cell balance threshold. An electronic device including such monitoring and balancing circuits is also provided. Various methods are also provided.

Abstract: An apparatus for use with a charge control system for affecting current draw from a charging unit coupled at an input locus of the charge control system for charging a battery unit includes a current sink switchingly coupled with the input locus for selectively contributing a predetermined current draw at the input locus. A method for selectively establishing a predetermined current draw from a charging unit coupled at an input locus with a charge control unit for charging a battery unit includes the steps of: (a) providing a current sink switchingly coupled with the input locus; (b) sensing at least one predetermined condition in the battery unit; and (c) switchingly engaging the current sink when the at least one predetermined condition satisfies at least one predetermined criteria.

Abstract: A method for activating a secondary battery is provided that enables sufficient activation of a secondary battery in a short time. A secondary battery is activated with a varying current, e.g., pulse current, in which current values in a charge direction and a discharge direction are repeated alternately in a cycle ranging from 1 to 30 seconds.

Abstract: The present method for indicating a battery state of a hybrid car detects &Dgr;V/&Dgr;I which is a change value of voltage and current from a first state and a second state of a battery 1 being charged/discharged. The battery state indicating method determines whether the battery is charged/discharged in a battery protective state based on the &Dgr;V/&Dgr;I and indicates that the battery protective state is established when the battery is charged/discharged in a protective state.

Abstract: An uninterruptible power supply includes a power supply unit for generating DC power at a predetermined voltage from AC power supplied from the outside to supply the DC power to an electronic device, and a rechargeable battery unit including rechargeable battery cells for storing the power supplied thereto from the power supply unit for supplying the electronic device with the power stored in the rechargeable battery upon service interruption of the AC power. The rechargeable battery unit includes a battery state monitoring unit for monitoring a state of the rechargeable battery cells and a communicating unit for notifying the electronic device of information indicative of the state of the rechargeable battery detected by the battery state monitoring unit. The rechargeable battery cells include nickel-metal hydride rechargeable batteries.

Abstract: A battery charger method and apparatus are disclosed for providing detailed battery status and charging method information for a selected one of multiple batteries that are simultaneously coupled to the battery charger. The battery charger includes a controller. The controller selects one of the batteries to monitor and charge. The controller then starts a measurement cycle for the selected battery. During the measurement cycle, the controller determines current battery characteristics of the selected battery. The controller determines whether the selected battery is ready for charging by determining whether the battery characteristics of the selected battery are within a specified range. If the controller determines that the selected battery is ready for charging, the controller causes the battery charger to start charging the battery. If the controller determines that the selected battery is not ready for charging, the controller selects another battery to monitor and charge.

Abstract: A nonaqueous-electrolyte secondary battery charging/discharging method that provides a prolonged cyclic life. In the charging/discharging method, a secondary battery is continuously charged unconditionally until a charging capacity exceeds 20% of a full charging capacity. The charging is completed when the charging capacity exceeds 70% of a full charging capacity. A maintenance charging/discharging operation is performed to avoid the full charging capacity being in an error state when dV/dt exceeds a specified value “a” before a charging current exceeds 70% of the full charging capacity. Likewise, the maintenance charging/discharging operation is performed to avoid the full charging capacity being in an error state when dT/dt exceeds a specified value “b” before a charging current exceeds 70% of the charging capacity.

Abstract: Testing apparatus senses the time-varying electrical response of an electrochemical cell/battery to time-varying electrical excitation. The cell/battery may, or may not, be in service. Computation circuitry responsive to the time-varying electrical response evaluates elements of a unique circuit model representation of the cell/battery. Performance parameters and physical parameters are computed from these element values. Computed performance parameters include, but are not limited to, “total storage capacity”, “absolute stored charge”, “state-of-charge”, “absolute cranking current”, “fully charged cranking current”, and “state-of-health”.

Abstract: The present invention relates to a cycle battery output control device, more particularly to a control device precisely monitoring the battery output and effectively extending its life, comprising a central control module, a battery module, an output module, a memory module, and a data module; characterized in that a low-voltage detecting unit of the central control module acts as a switch between battery modules to timely control the function of the output module, and count the number of times that the detecting unit monitors the cycle switching output route with the previous battery at any time to assure the exhaustion of the electricity storage of the previous battery module, and working with the voltage indicating unit to timely turn on or off the light and correctly indicate the exhaustion of electricity storage of the battery module and the charging indicating unit to alert a blinking light to show the status of switching to the last battery module for the cycle switch in order to attain the effect of p

Abstract: A power charger which charges and provide conditioned power from at least one of a super-capacitor and a secondary battery. The type of energy device is user selectable, such that the user can select super-capacitors because of their much longer charge/discharge life and low-maintenance requirements, while another user can chose secondary batteries because of their higher stored energy, while a third user may select a combination of the two.

Abstract: When an electronic timepiece is in a power-saving mode in which the current time display is suspended, it is determined whether or not the charge voltage supplied from a high-capacity capacitor is higher than a predetermined reference voltage, and if higher, enough electrical energy is stored in the high-capacity capacitor to return from the power-saving mode to the display mode, so that a current time restoration process is performed upon detecting power generation. On the other hand, if the charge voltage is less than or equal to the predetermined reference voltage, the supply of the power supply voltage to the control circuits is stopped to prevent the electrical energy stored in the high-capacity capacitor from being consumed needlessly. As a result, the electronic timepiece can be reactivated quickly when the power generating device begins to generate power.

Abstract: A method of and system for determining the state-of-health of a proton exchange membrane fuel cell stack connected to a load comprises detecting the real part of the impedance Z1 of the fuel cell stack at a selected frequency; detecting the voltage V1 of the fuel cell stack at open circuit; detecting the voltage V2 of the fuel cell stack when the maximum load current is being drawn from said fuel cell stack; and determining the state of health of said fuel cell stack from a fuzzy system trained in a relationship between said real part of the impedance of the fuel cell stack at the selected frequency, the voltage of the fuel cell stack at open circuit, and the voltage of the fuel cell stack when the maximum load current is being drawn from said fuel cell stack.

Abstract: A method for producing a nickel metal-hydride storage battery includes: (i) assembling a battery by enclosing the positive electrodes, the negative electrodes, separators, and an electrolyte in a case; (ii) charging the battery with electric current in a range of 0.05 C (ampere) to 0.2 C (ampere) until a state of charge rises to a range of 10% to 30%; (iii) overcharging the battery that has been subjected to the charging, with electric current in a range of 0.2 C (ampere) to 1 C (ampere), and thereafter discharging the same until the state of charge lowers to 10% or below; and (iv) subjecting the battery after overcharging to a plurality of charging-discharging cycles, each charging-discharging cycle being composed of charging the battery that has been subjected to the overcharging, with electric current in a range of 0.2 C (ampere) to 5 C (ampere) until the state of charge rises to a range of 60% to 95%, and discharging the same until a battery voltage lowers to a range of 0.70 V to 1.05 V.

Abstract: A method of and system for determining the state-of-health of a lead acid battery of the type commonly used in portable external defibrillators comprises detecting an impedance characteristic of the battery at at least one selected frequency, counting the number of complete charge/discharge cycles that the battery undergoes, and determining the state of health of the battery from a fuzzy system trained in a relationship between the impedance characteristic and the cycle number of the lead acid battery and the state-of-health, wherein the state-of-health is a function of and varies with the battery's ability to deliver power required by the load and the battery's capacity to meet load requirements.