`Rogers
`
`US00544.4378A
`Patent Number:
`11
`(45) Date of Patent:
`
`5,444,378
`Aug. 22, 1995
`
`54)
`(75)
`
`(73)
`
`(*)
`
`21
`22
`
`63
`
`51
`52
`58)
`
`Assignee:
`
`Notice:
`
`Appl. No.:
`Filed:
`
`BATTERY STATE OF CHARGE MONITOR
`Wesley A. Rogers, Grosse Pointe
`Inventor:
`Park, Mich.
`Electronic Development Inc., Grosse
`Pointe Park, Mich.
`The portion of the term of this patent
`subsequent to Jan. 12, 2010 has been
`disclaimed.
`919,011
`Jul. 23, 1992
`Related U.S. Application Data
`Continuation-in-part of Ser. No. 607,237, Oct. 31, 1990,
`Pat. No. 5,179,340, which is a continuation-in-part of
`Ser. No. 218,539, Jul. 13, 1988, Pat. No. 4,968,941.
`Int. Cl. ........................................... G01N 27/416
`U.S. C. .................................... 324/428; 324/431;
`320/48
`Field of Search ............... 324/426, 427, 428, 431;
`320/48; 340/636
`
`56)
`
`References Cited
`U.S. PATENT DOCUMENTS
`3,805,157 4/1974 Acks et al. .......................... 324/428
`4,388,618 6/1983 Finger ................................. 340/636
`4,740,754 4/1988 Finger ................................. 324/428
`4,947,123 8/1990 Minezawa ........................... 324/427
`4,968,941 11/1990 Rogers.
`... 324/428
`5,179,340 1/1993 Rogers ................................ 324/428
`
`
`
`OTHER PUBLICATIONS
`Ferrgiolo et al., “Available Battery Time Sensor', vol.
`16, No. 5, Oct., 1973.
`Primary Examiner-Kenneth A. Wieder
`Assistant Examiner-Glenn W. Brown
`Attorney, Agent, or Firm-Davis Hoxie Faithfull &
`Hapgood
`ABSTRACT
`57
`An apparatus and method for monitoring the state of
`charge of the battery having a shunt resistor connected
`in series with a battery and an integrating circuit con
`nected across the terminals of the shunt resistor which
`includes a large capacitance element having the capabil
`ity to store charge for long periods of time, so that the
`integration can be performed along the same curve even
`if power to the integrating circuit is interrupted during
`continuous or intermittent use. The apparatus and
`method are applicable to batteries for automotive vehi
`cles. Temperature compensation schemes to adjust the
`state of charge monitoring circuit to correct for changes
`in battery performance characteristics with temperature
`are provided. A circuit for detecting the existence of a
`defective battery cell is provided. A system for moni
`toring charging and discharging of the battery over
`time and identifying various battery conditions and
`potential battery or battery charging system failures is
`provided.
`
`65 Claims, 5 Drawing Sheets
`
`Petitioner Intel Corp., Ex. 1033
`IPR2023-00783
`
`
`
`U.S. Patent
`U.S. Patent
`
`Aug. 22, 1995
`Aug. 22, 1995
`
`
`
`Sheet 1 of 5
`Sheet 1 of 5
`
`5,444,378
`
`5,444,378
`
`FIG. 2
`
`TO LOAD
`
`Petitioner Intel Corp., Ex. 1033
`IPR2023-00783
`
`Petitioner Intel Corp., Ex. 1033
`IPR2023-00783
`
`
`
`U.S. Patent
`U.S. Patent
`
`
`
`Aug, 22, 1995
`Aug. 22, 1995
`
`5,444,378
`
`Sheet 2 of 5
`Sheet 2 of 5
`
`5,444,378
`
`Petitioner Intel Corp., Ex. 1033
`IPR2023-00783
`
`Petitioner Intel Corp., Ex. 1033
`IPR2023-00783
`
`
`
`U.S. Patent
`U.S. Patent
`
`Aug. 22, 1995
`Aug. 22, 1995
`
`Sheet 3 of 5
`Sheet 3 of 5
`
`5,444,378
`5,444,378
`
`
`
`OWS|ev‘€NidWOHre
`
`Petitioner Intel Corp., Ex. 1033
`IPR2023-00783
`
`Petitioner Intel Corp., Ex. 1033
`IPR2023-00783
`
`
`
`U.S. Patent
`
`Aug, 22, 1995
`
`Sheet 4 of 5
`
`5,444,378
`
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`
`Petitioner Intel Corp., Ex. 1033
`IPR2023-00783
`
`Petitioner Intel Corp., Ex. 1033
`IPR2023-00783
`
`
`
`U.S. Patent
`
`Aug. 22, 1995
`
`Sheet 5 of 5
`
`5,444,378
`
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`Petitioner Intel Corp., Ex. 1033
`IPR2023-00783
`
`Petitioner Intel Corp., Ex. 1033
`IPR2023-00783
`
`
`
`
`15
`
`30
`
`1.
`
`BATTERY STATE OF CHARGE MONTOR
`
`RELATED APPLICATIONS
`This application is a continuation-in-part of U.S. pa
`tent application Ser. No. 07/607,237, filed Oct. 31, 1990,
`in the name of Wesley A. Rogers and entitled Appara
`tus for Monitoring The State of Charge of a Battery,
`now issued as U.S. Pat. No. 5,177,340, which is a con
`10
`tinuation-in-part of U.S. application Ser. No.
`07/218,539, filed Jul. 13, 1988, in the name of Wesley A.
`Rogers and entitled Apparatus For Monitoring the
`State of Charge of a Battery, now issued as U.S. Pat.
`No. 4,968,941.
`FIELD OF THE INVENTION
`This invention relates to improved devices for moni
`toring the state of charge of a battery, more specifically,
`to more efficient devices for monitoring the state of
`charge of an automobile vehicle battery and providing
`20
`diagnostic capability under varying temperature condi
`tions.
`BACKGROUND OF THE INVENTION
`In the normal operation of an automotive vehicle, a
`25
`12-volt battery is used to start the engine and to operate
`accessories at times when the motor is not running. An
`alternator is used to recharge the battery after each start
`and to maintain it fully charged. Once the engine is
`started the alternator is driven by the rotation of the
`engine crankshaft.
`Conventional automotive batteries have six cells con
`nected in series with thin cell plates and are well suited
`to developing large starting currents of 240 amps. It has
`long been the practice, in order to insure that the bat
`35
`tery is adequately charged following a start discharge,
`to maintain a recharging current flow to the battery at
`a level that varies as a function of ambient temperature.
`This results in trickle charge currents. These trickle
`charge currents cause prior known battery state of
`40
`charge monitors to indicate erroneously greater than a
`100% charge. This results in erroneous state of charge
`readings.
`It is known to monitor the state of charge of a battery
`to determine, for example, whether a battery is fully
`45
`charged, depleted of charge, or partially charged. One
`such technique calls for measuring the specific gravity
`of the electrolyte of each cell of the battery using a
`hydrometer. The determined specific gravity can be
`compared to the specific gravity of the battery in a fully
`50
`charged state to obtain a relative state of charge.
`Another technique uses a current counter which con
`tinuously registers the net current from automotive
`battery and is disclosed in the ELV Journal No. 45,
`dated May/June 1986. That technique measures the
`55
`voltage drop across a precision shunt resistor in series
`with the monitored battery. The voltage is amplified
`and drives a voltage to frequency converter, the output
`of which is fed into an up/down counter. The counter
`counts up or down while the battery is discharged or
`being charged respectively, and may drive an inte
`grated display. The display is initialized when the
`counter is first connected to a fully charged battery and
`displays the net current flow from the battery. For
`continuous monitoring, the display must be continu
`65
`ously energized by a power source so that the counter
`will not lose the net count through loss of power. U.S.
`Pat. No. 4,968,941, which issued to the assignee of the
`
`5,444,378
`2
`present invention, teaches a battery state of charge
`monitoring circuit (“BSOC circuit') including a shunt
`resistor in series with the battery and a circuit for inte
`grating the voltage drop across the shunt having a very
`large capacitance in the feedback path. The large capac
`itance device, such as a Super Capacitor having a ca
`pacitance between 0.01 and 1 farad or more, integrates
`the current flow into and out of the battery over time,
`respectively, and thus maintains a charge at a level
`corresponding to the battery state of charge. The
`charge is maintained for long periods of time whether
`or not the element is connected to a power supply be
`cause of the long RC time-constant of the integrator
`amplifier circuit and a very low self-discharge rate of
`the capacitive device. The BSOC circuit may be con
`nected to a display and initialized with a fully charged
`battery so that the voltage stored in the large capaci
`tance device represents the state of charge of the bat
`tery. Alternatively, the BSOC circuit may be connected
`to a discharged battery such that the capacitive device
`is charged up with the battery.
`The present invention concerns improvements to the
`basic BSOC circuit disclosed in U.S. Pat. No. 4,968,941,
`the disclosure of which is hereby incorporated by refer
`ence in its entirety.
`SUMMARY OF THE INVENTION
`It is an object of the present invention to provide a
`battery state of charge ("BSOC') device for an automo
`tive vehicle that is more efficient than prior known
`devices. It is another object to provide a BSOC device
`that is permanently connected to the battery being mon
`itored.
`It is another object of the invention to combine moni
`toring the state of charge of a battery and the charging
`current applied to the battery after it reaches full charge
`to identify a defective battery.
`It is another object of the invention to monitor the
`state of charge of a battery and to compensate for
`changes in the battery operating characteristics such as
`temperature, load current magnitude, and self-leakage.
`It is another object of the invention to warn the vehi
`cle operator of a low battery state of charge or a defec
`tive battery condition.
`In accordance with the present invention, apparatus,
`systems, and methods are provided for monitoring con
`tinuously the state of charge of an electrical energy
`source, in particular, a battery of an automotive vehicle.
`One aspect of the present invention concerns provid
`ing the BSOC circuit with one or more temperature
`compensation circuits for tracking changes with tem
`perature of the battery characteristics, such as battery
`capacity and the self-discharge rate of the battery and
`the BSOC circuit. For example, in colder temperatures
`the charging voltage delivered by a conventional bat
`tery charging system, i.e., the alternator, to recharge the
`battery is increased to compensate for the lower battery
`capacity at those temperatures and is reduced below the
`72 F. level in warmer ambients. Similarly, at the colder
`temperatures, the self-discharge rate of the battery will
`become lower than at warmer temperatures. Accord
`ingly, improvements in tracking the charge capacity of
`the battery being monitored are obtained by adjusting
`the characteristics of the BSOC circuit to correspond to
`charges in the battery characteristics with changing
`temperature. This yields a more accurate model of the
`battery and its measured charge.
`
`Petitioner Intel Corp., Ex. 1033
`IPR2023-00783
`
`
`
`O
`
`15
`
`5,444,378
`4.
`3
`circuit incorporating the thermistor which controls the
`Another aspect of the invention concerns improved
`offset voltage of the amplifier. This results in altering
`methods and apparatus for monitoring of the state of an
`electrical energy source having a charge capacity and a
`the charging rate and discharging rate of the capacitive
`self-discharge rate that changes with temperature. One
`element as a function of the sensed temperature. Alter
`natively, the circuit may include a thermistor for adjust
`such apparatus includes:
`ing the selfdischarge rate of the capacitive element in
`a current sensor operatively connected to the energy
`source for producing an output signal related to the
`response to the sensed temperature. In this embodiment,
`the output of the amplifier reflects the state of charge as
`magnitude and direction of the current flowing to
`a function of temperature. Preferably, the circuit in
`or from said energy source;
`a low self leakage capacitive element having a capaci
`cludes both the balance circuit and the circuit for ad
`justing the self discharge rate.
`tance of 0.01 farad or more connected to said cur
`rent sensor for integrating said output signal and
`Another aspect of the invention concerns improving
`for producing a signal related to the state of the
`the efficiency of the state of charge circuit elements to
`energy source, said capacitive element charging at
`avoid the need for operation in a standby mode and an
`a rate proportional to the magnitude of the sensed
`active mode, such that the standby mode has a reduced
`drain current on the energy source when the energy
`current when the current flow is in one direction,
`and discharging at a rate proportional to the magni
`source current flow is below selected thresholds corre
`sponding to being in use. In this regard, the invention
`tude of the sensed current when the current flow is
`concerns using low power operational amplifiers hav
`in the opposite direction, on a continuous basis as
`ing supply voltages provided directly from the energy
`the current flows to and from said energy source;
`a device for monitoring the temperature of the en
`source being monitored, for sensing and integrating the
`current flow charged to and discharged from the capac
`ergy source; and
`a circuit for adjusting the integrated signal in re
`itive element. Advantageously, the amplifier has a drain
`sponse to the temperature of the energy source so
`current of about 0.2 mA and the entire state of charge
`that the integrated signal corresponds to the state
`monitoring circuit has a drain current of approximately
`25
`of charge of the energy source at the sensed tem
`2 mA or less.
`Another aspect of the invention concerns detecting
`perature.
`Preferably, the current sensor is a shunt in series with
`the existence of a defective cell in the energy source. In
`the energy source, the apparatus includes an operational
`one embodiment, a first circuit is used to determine
`when the integrator amplifier output reflects a full
`amplifier having the capacitive element in the feedback
`charge, namely a charge that is a high percent of 100%
`path and an input resistor across which the output signal
`from the current sensor is passed for integrating the
`charge. A second circuit is used to determine when
`output signal, and the device for monitoring tempera
`there is a charging current to the energy source, namely
`ture is a thermistor placed in physical proximity to the
`when the current flow into the energy source is above
`energy source. Although immersion of the temperature
`a threshold current level representative of a charging
`35
`current. A third circuit is used for determining when
`monitoring device inside the energy source would be
`the energy source is fully charged and also has a charg
`optimal, it is believed to be sufficient for most circum
`ing current above the threshold level, which conditions
`stances that the device be placed in the same ambient
`are representative of a defective cell. Preferably, the
`conditions as the energy source, optionally in touching
`energy source is a multi-cell battery, and the full charge
`contact. Thus, in the context of an automobile, sensing
`ambient temperature in the engine compartment near
`level and threshold current levels are selected to corre
`spond to one or more cells of the battery having a short
`the battery will suffice, particularly in view of the mini
`mal thermal heating of the battery due to increasing
`circuit. In another embodiment, the apparatus includes
`engine temperature.
`a diagnostic meter for immediately indicating when
`In one such preferred embodiment, the adjusting
`there exists a full charge and excessive charging cur
`45
`circuit includes the thermistor in series with the ampli
`ent.
`Another aspect of the invention concerns detecting
`fier output and a resistor divider network. This circuit
`adjusts the output voltage of the operational amplifier
`when the energy source is fully charged and when there
`to correspond to the charge capacity of the battery at
`is a trickle charging current to the energy source. This
`circuit is used to prevent the integrating amplifier from
`the sensed temperature. In this embodiment, the capaci
`50
`tive element is charged and discharged at preselected
`integrating the trickle charging current and indicating
`rates that do not change with temperature and only the
`more than 100% charge.
`integrated output signal is adjusted. Thus, the signal
`In another embodiment, the BSOC circuit is coupled
`input into the adjusting circuit is the integrated output
`to a microprocessor that monitors the polarity and mag
`signal of the amplifier corresponding to the instanta
`nitude of current flow across the shunt over time to
`neous state of charge of the battery independent of the
`determine when the energy source charging and dis
`temperature, and the adjusting circuit provides at its
`charging operating characteristics are acceptable or
`output a signal corresponding to the charge capacity of
`unacceptable, and for providing an indication of the
`the battery at the sensed temperature. Both signals are
`characteristics to the vehicle operator.
`useful for diagnostic purposes as described below.
`It should be understood that the various aspects of
`the invention may be used jointly and severally, are not
`In another such preferred embodiment, the adjusting
`limited to monitoring the state of charge of a battery for
`circuit includes a circuit for adjusting the rates at which
`the capacitive element is charged or discharged to re
`automotive vehicles, and are applicable to monitoring
`any rechargeable electrical energy storage device that is
`flect changes in the capacity of the battery with changes
`in the sensed temperature at the time of charge or dis
`connected to operate an electrical load, for example,
`65
`charge, and so that the integrated output signal corre
`household or industrial appliances, a battery powered
`sponds to the state of charge of the battery at the sensed
`vehicle or device, aircraft, spacecraft, watercraft or
`emergency lighting.
`temperature. In this regard, the circuit may be a balance
`
`30
`
`55
`
`60
`
`Petitioner Intel Corp., Ex. 1033
`IPR2023-00783
`
`
`
`O
`
`5
`BRIEF DESCRIPTION OF THE DRAWINGS
`Further features of the invention, its nature and vari
`ous advantages will be more apparent from the accom
`panying drawings and the following detailed descrip
`tion of the invention, in which like reference numerals
`refer to like elements, and in which:
`FIG. 1 and 1A are respectively battery state of
`charge monitors connected across a shunt resistor in a
`circuit in accordance with various aspects of the present
`invention;
`FIG. 2 is a schematic of one embodiment of an inte
`grating circuit of a battery state of charge circuit with
`temperature compensation in accordance with the pres
`ent invention;
`FIG. 3 is a schematic of one embodiment of an inte
`grating circuit of a battery state of charge circuit with a
`defective battery sensing circuit in accordance with the
`present invention;
`FIG. 3A is a schematic of an inverting double inte
`grating circuit configuration of FIG. 1A;
`FIG. 4 is a schematic diagram of a battery state of
`charge monitor in accordance with a preferred embodi
`ment of the present invention;
`25
`FIG. 5 is a schematic diagram of a battery state of
`charge monitor in accordance with an alternate pre
`ferred embodiment of the present invention;
`FIG. 6 is a schematic diagram for a non inverting
`integrating circuit of FIG. 1A;
`30
`FIG 7 is a elevated perspective sectional view of a
`battery state of charge monitor of FIG. 1.
`DETALED DESCRIPTION OF THE
`INVENTION
`35
`Referring to FIGS. 1 and 1A of the drawings, a Bat
`tery State of Charge (BSOC) monitor 16 is illustrated in
`a circuit with a battery 20, such as a 12 volt automotive
`battery or any other energy storage device, which
`supplies power to a load 5, such as a starter motor or
`electrical circuits in an automobile, and which can be
`charged by an alternator/battery charger 40. A shunt
`resister 30 is in series with the battery 20 and the load 5.
`Referring to FIG. 1, the input terminals of the BSOC
`monitor 16 are connected to the terminals 22 and 24 of
`45
`the shunt resister 30. Referring to FIG. 1A, the input
`terminals of BSOC monitor 16 are connected to termi
`nal 22 of shunt 30 and to ground, with the other termi
`nal of shunt 30 being connected to ground.
`A temperature monitoring device 28, such as a therm
`50
`istor, is placed in proximity to battery 20 and is electri
`cally connected to BSOC monitor 16 for adjusting the
`output level of BSOC monitor 16in response to changes
`in temperature. Preferably, temperature monitor device
`28 is located in the BSOC monitor enclosure 716 which
`is mounted between the battery terminals as illustrated
`in FIG. T.
`Shunt resistor 30 is connected in series with battery
`20 and load 5, preferably interposed between the nega
`tive pole of battery 20 and ground, wherein load 5 pres
`ented by the vehicle is connected between the positive
`terminal of battery 20 and ground. Consequently, the
`voltage drop V, across shunt resistor 30 is related to the
`current flowing through battery 20 by its scale factor
`(MV/AMP). The current can be either in direction 25
`65
`or 26, depending on whether battery 20 is discharging
`current to load 5 or being charged by alternator/battery
`charger 40, respectively.
`
`55
`
`5,444,378
`6
`Voltage Vs across shunt 30 is input to BSOC monitor
`16 which produces an output signal Vi that corresponds
`to state of charge of battery 20. BSOC monitor 16,
`therefore, tracks amp hours into and out of the battery
`20 by acting as a model of the battery 20.
`FIG. 2 shows one embodiment of BSOC monitor 16
`as an inverting integrating circuit, in accordance with
`the temperature compensation aspect of the present
`invention. A resistor R1 is connected in series with an
`input voltage Vs and the inverting input of an opera
`tional amplifier 34. A device C1, having a large capaci
`tance, is in the feedback path of amplifier 34. The large
`capacitance device C1 is preferably a super capacitor,
`for example, product number FYHOH105Z manufac
`tured by NEC Corporation, which is capable of storing
`a charge for up to three years. The output of this circuit
`V(t), is as follows:
`
`15
`
`where V(t) is the voltage drop across shunt resistor 30
`over time t, and c is a constant of integration which
`equals the initial charge on the device 36.
`Signal V(t) is then processed by circuit 38 which
`includes temperature monitoring device 28 in proximity
`to battery 20, for adjusting the signal V(t) as a function
`of sensed temperature. The output of circuit 38 is signal
`V(t) which is representative of the charge capacity of
`battery 20 at the sensed temperature.
`FIG. 3 shows one embodiment of BSOC monitor 16
`as an inverting integrating circuit in accordance with
`the defective battery sensing embodiment of the present
`invention. In this embodiment, the integrating circuit
`includes resistor R1 connected in series with an input
`voltage V(t), and the inverting input of operational
`amplifier 34, and large capacitance device C1 in the
`feedback path in series with resistor R1. A circuit 39 is
`provided for monitoring the current flow into and out
`of battery 20 and the integrated output signal V(t), and
`for actuating a warning device 41 when the sensed
`charge and charging current indicate that battery 20 is
`defective. Warning device 41 may be, for example, an
`indicator light on an instrument panel of a vehicle or a
`logic gate polled by a microprocessor or a state device.
`FIG. 3A shows an embodiment of BSOC monitor 16
`in an inverting, double-ended integrating circuit config
`uration. In this embodiment, the inverting input of oper
`ational amplifier 34A is connected in series with input
`voltage V(t) across input resistor R1 with large capaci
`tance device C1 in the feedback loop. The non-invert
`ing input of amplifier 34A is connected in series with
`battery 20 voltage Vb across a potentiometer P1. Opera
`tional amplifier 34A also is configured with the positive
`reference voltage connected to battery 20 and the nega
`tive reference voltage connected to ground. Potentiom
`eter P1 is adjusted to provide a voltage input of one half
`the rated voltage of battery 20 on the non-inverting
`input, e.g., 6 volts for a 12 volt battery. This places an
`integrator output voltage Vi at 6 volts with no voltage
`appearing at the top of shunt 30. Although usable in a
`BSOC monitor 16, this embodiment requires shunt scale
`factor (mV to A) adjustments which are not required
`with the non-inverting input configuration shown in
`FIG. 3.
`Referring to FIG. 4, one embodiment of a BSOC
`monitor 16 is shown. BSOC monitor 16 includes
`
`Petitioner Intel Corp., Ex. 1033
`IPR2023-00783
`
`
`
`5
`
`10
`
`15
`
`5,444,378
`7
`8
`standby power circuit 220, battery discharge turn-on
`is desirable, such as the RCA Model No. CA 3140AE,
`circuit 230, start circuit 240, battery charge turn-on
`operating in a single ended mode.
`circuit 250, integrator circuit 260, and display driver
`Battery discharge turn-on circuit 230 also may be
`circuit 290. In this embodiment, BSOC monitor 16 oper
`provided with a manual switch 232 for connecting volt
`ates in one of a standby or off mode and an operating
`age regulator VR2 directly to battery 20. This is useful
`mode. In the standby mode, BSOC monitor 16 con
`for manually turning on BSOC monitor 16 for diagnos
`sumes a standby current of about 0.8 ma. This current is
`tic purposes, in particular to determine whether or not
`used by battery discharge turn-on circuit 230 and bat
`BSOC monitor 16 is accurately measuring the state of
`tery charge turn-on circuit 250 to monitor any signifi
`charge of battery 20.
`cant discharge and charge of battery 20, respectively.
`Battery charge turn-on circuit 250 is provided to turn
`BSOC monitor 16 changes from its standby to operating
`on BSOC monitor 16 when battery 20 is being charged.
`mode when a sufficient discharge or charge is detected.
`In this regard, when a -0.2 volt or greater input ap
`In the operating mode, BSOC monitor 16 has an operat
`pears across shunt 30, that signal will be amplified by
`ing current of about 45 ma for the various circuit func
`amplifier A5 to produce a signal that turns on transistors
`tions which are described below.
`Q6 and Q5 to turn on transistor Q2, thereby changing
`Standby power circuit 220 includes a conventional
`BSOC monitor 16 from the standby mode to the operat
`voltage regulator VR1 that produces a regulated +6.0
`ing mode.
`volts dc output. In the standby mode, regulator VR1 is
`By way of example, during vehicle operation with a
`energized directly from battery 20. The +6 volt output
`fully charged battery, currents of as low as 1 ampere are
`signal is used to energize amplifier Al of battery dis
`supplied to the input terminal of battery 10. This current
`20
`charge turn-on circuit 230 and amplifier A5 of battery
`produces a -2.0 mv signal across shunt 30 (assuming
`charge turn-on circuit 250. The --6 volt signal also is
`that a shunt having a 2 mv to 1 ampere ratio is used),
`used as the voltage source of the collector currents for
`which signal is then amplified to turn on pass transistor
`transistors Q7 and Q8 of battery discharge turn-on cir
`Q2.
`cuit 230 and transistor Q6 of battery charge turn-on
`Turning BSOC circuit 16 on enables integrator cir
`25
`circuit 250. The collector of transistor Q2 also is di
`cuit 260 to track changes in the state of charge of bat
`rectly energized by battery 20.
`tery 20. Integrator circuit 260 preferably comprises an
`In the standby mode, amplifier Al has no output and
`operational amplifier A2 having a very large capaci
`transistors Q7 and Q8 are turned off. This results in
`tance device (hereinafter a "capacitor') C1 having a
`transistor Q2 being off and no voltage being applied to
`long time-constant in the feedback loop connecting the
`the input of voltage regulator VR2 of discharge turn-on
`output at pin 6 of amplifier A2 to the inverting input at
`circuit 230. Consequently, start circuit 240 and integra
`pin 2 of amplifier A2. Capacitor C1 may be a super
`tor circuit 260 are off and the drain current on battery
`capacitor having a capacitance of 0.01 farad or greater,
`20 is minimized.
`e.g., model FYHOH105Z manufactured by NEC Cor
`Battery discharge turn-on circuit 230 is provided to
`poration, a "gold capacitor, ' model NF series P/N
`turn on the circuit when battery 20 is discharging.
`EECF5R0105 available from Panasonic, or a similar
`When a load of -0.1 amps or more is drawn from bat
`device that has a long time-constant and is capable of
`tery 20, a voltage of -0.2 mv or higher appears across
`storing a charge over substantially long time periods of
`resistor R2 and is amplified across resistor R3 by ampli
`many months or years. The non-inverting input at pin 3
`fier Al. The amplified positive voltage at pin 6 of ampli
`of amplifier A2 is connected to shunt 30 at node 32 and
`the inverting input at pin 2 of amplifier A2 is connected
`fier Al turns transistors Q7 and Q8 on. This reduces the
`base of transistor Q2 to ground potential and thus turns
`to ground potential through resistor R1 and integrator
`discharge interrupter circuit 270.
`on transistor Q2. As a result, transistor Q2 then applies
`the 12 volts at the collector of transistor Q2 to the input
`Integrator discharge interrupter circuit 270 includes
`of voltage regulator VR2. This provides voltage regula
`transistor Q5A configured with the collector connected
`45
`torVR2 with a regulated output voltage of +6 volts dc.
`to resistor R1, the emitter connected to ground poten
`The +6 v supply is provided to amplifiers A2, A3, and
`tial, and the base connected to the 4-6 volt source volt
`A4 and provides the reference or source voltage of --6
`age from voltage regulator VR2 across limiting resistor
`(VR2)as indicated on the schematic of FIG. 4 for inte
`R21. When BSOC monitor 16 is in the standby mode,
`grator circuit 260, display driver circuit 290, and start
`the voltage from VR2 is 0 and transistor Q5A is turned
`circuit 240. When this occurs, BSOC monitor 16 is fully
`off. Thus, there is substantially no leakage current flow
`operational.
`ing out of capacitor C1. When BSOC monitor 16 is in
`By way of example, the current required to turn on a
`the operational mode, the voltage from regulator VR2
`single light bulb in a conventional automotive vehicle
`is --6 volts, transistor Q5A is turned on, and resistor R1
`such as when a door is opened is about 1.0 amp. Ac
`is thus connected to ground potential. This in turn al
`55
`cordingly, shunt resistor 30 may be selected to produce
`lows integrator circuit 260 capacitor C1 to charge or
`about 2.0 mv thereacross for every amp discharged
`discharge through resistor R1.
`from battery 20. This scale factor (MV/AMP) provides
`In the operating mode, the current flow into and out
`an adequate voltage output level at relatively low turn
`of battery 20 passes through shunt 30 and the voltage
`on currents and provides acceptable signal processing.
`generated across shunt 30 is detected and integrated by
`Of course, a shunt resistor having a different mv to
`amplifier A2. The output of amplifier A2 at pin 6 thus
`ampere ratio could be used, e.g., 1 mv to 1 ampere,
`represents the net amp hours into and out of the battery.
`subject to adjustments of the signal processing circuits
`This provides an accurate indication of the state of
`to determine the battery state of charge, which adjust
`charge of battery 20 by integrating the current into and
`ments are within the ability of a person of ordinary skill
`from battery 20 (or other energy storage device) over
`in the art. With a 1 mv to 1 ampere ratio, an operational
`time.
`amplifier capable of detecting and amplifying 0.5 mv
`The components of integrator circuit 260 and shunt
`voltage swings as small as 0.5 mv and as large as 200 mV
`30 are selected to allow integrator circuit 260 to follow
`
`30
`
`35
`
`50
`
`65
`
`Petitioner Intel Corp., Ex. 1033
`IPR2023-00783
`
`
`
`20
`
`25
`
`35
`
`5
`
`10
`
`15
`
`5,444,378
`10
`9
`lower collector voltage initiates a current flow through
`the discharge curve of battery 20. For example, if a
`resistor R4 to ground. As the amplitude of the voltage
`shunt resistance of 2 mv per ampere is selected for use
`with an 80 amp-hour battery having a 1 ampere dis
`across R31 increases above -0.1 volt, transistor Q4 is
`charge rate and a capacitor having a voltage range of
`driven into saturation and a large simulated start current
`from 0 to 100 mv and a capacitance of 1.8 farads, then
`is passed through resistor R4 to ground.
`for