WO1992015022A1 - Controle des batteries a courant fort - Google Patents

Controle des batteries a courant fort Download PDF

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Publication number
WO1992015022A1
WO1992015022A1 PCT/AU1992/000055 AU9200055W WO9215022A1 WO 1992015022 A1 WO1992015022 A1 WO 1992015022A1 AU 9200055 W AU9200055 W AU 9200055W WO 9215022 A1 WO9215022 A1 WO 9215022A1
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WO
WIPO (PCT)
Prior art keywords
battery
voltage
current
test
conditioning
Prior art date
Application number
PCT/AU1992/000055
Other languages
English (en)
Inventor
Anton Schubert
Dennis Charles Mills
Terence Harvey
George Michael Leigh
Original Assignee
Commonwealth Scientific And Industrial Research Organisation
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Commonwealth Scientific And Industrial Research Organisation filed Critical Commonwealth Scientific And Industrial Research Organisation
Priority to AU12461/92A priority Critical patent/AU652029B2/en
Publication of WO1992015022A1 publication Critical patent/WO1992015022A1/fr

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Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
    • G01R31/36—Arrangements for testing, measuring or monitoring the electrical condition of accumulators or electric batteries, e.g. capacity or state of charge [SoC]
    • G01R31/3644—Constructional arrangements
    • G01R31/3648—Constructional arrangements comprising digital calculation means, e.g. for performing an algorithm
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
    • G01R31/36—Arrangements for testing, measuring or monitoring the electrical condition of accumulators or electric batteries, e.g. capacity or state of charge [SoC]
    • G01R31/385—Arrangements for measuring battery or accumulator variables
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
    • G01R31/36—Arrangements for testing, measuring or monitoring the electrical condition of accumulators or electric batteries, e.g. capacity or state of charge [SoC]
    • G01R31/385—Arrangements for measuring battery or accumulator variables
    • G01R31/386—Arrangements for measuring battery or accumulator variables using test-loads

Definitions

  • This invention relates to the testing of heavy current batteries such as lead-acid batteries, and more particularly to an improved method and apparatus for testing such batteries.
  • the invention has particular utility in the field of automotive starting, lighting and ignition (SLI) batteries but is not limited to this use.
  • the most common and most widely accepted method for determining the condition (i.e. good, fair, bad, etc.) of an automotive SLI battery is to subject it to a heavy current load and to measure its voltage during the load period and as it recovers when the load is removed.
  • the load is in the range from 100 Amps to 300 Amps and is intended to be a test of the battery's ability to deliver the currents drawn by a starter motor during the cranking of an automotive engine.
  • tester manufacturers normally do not reveal details of the decision making process whereby the voltages recorded are used to classify the battery under test as good, fair, recharge and retest, or bad, etc..
  • batteries which are presented for testing are most often in a flat condition.
  • a battery will not generally be presented for testing unless it has been giving trouble, and frequently it will have been flattened by continuously attempting to start an engine.
  • a large need to test flat batteries exists in the battery reclaim industry, where replaced batteries, in numbers of several hundreds at a time, are to be sorted. Virtually all of these batteries will be in states of charge below 11 volts, with many as low as 8 volts.
  • test apparatus deals with this difficulty by measuring the battery voltage before applying the heavy current and, if the voltage is too low for the decision making method to be reliable, discontinues the test and displays an instruction to recharge the battery and retest. Since the time to charge a battery is at least several hours, having to recharge it before achieving a decision on the battery condition is a considerable inconvenience.
  • Great Britain Patent No. 2182155 discloses a method for determining the state of charge of a battery by applying a brief high current boost charge (of less than 1% of the battery's capacity in a time of about 1 second) and instantly scanning the thus boosted battery to establish the voltage level at which the battery is capable of providing a discharge current at its C-rate (current numerically equal to the Amp-hour rate of the battery) .
  • This voltage level allows the degree to which the battery is charged to be estimated by comparison with data accumulated from large numbers of batteries of the type concerned at various known degrees of charge.
  • GB 2182155 is for the purpose of determining the charge in a battery, i.e., it is a type of battery
  • United States Patent No. 3857087 also discloses a battery test method involving various sequential discharging-charging steps.
  • the objective in this case is the determination of the goodness/badness of lead-acid batteries including those that are low in charge.
  • the discharging and charging sequences are based upon the inventor's theory that the goodness/badness of a battery can be assessed from polarisation effects which accompany the passage of current out of and into the battery.
  • the various test sequences include applying very short duration, controlled voltage, high current charge impulses (for example 100-300 amps for about 55 milliseconds at 15 volts) and heavy current discharging (for about 5 seconds) with rest periods therebetween to allow the battery to recover from ion depletion or ion absorption in the region of the electrodes, i.e., to recover from the polarisation of the electrodes.
  • the polarisation changes are measured in terms of voltage changes and the battery condition is assessed from comparisons with reference values obtained from a large number of tests on batteries in known conditions.
  • the invention therefore provides a method of testing a heavy current battery to determine the condition of the battery, characterised in that, said method involves the steps of measuring the battery output voltage and determining therefrom whether the battery is sufficiently charged to enable a valid heavy current discharge test to be performed and, if sufficiently charged, performing a heavy current discharge test and recording the battery loaded voltage V. after a predetermined time during said test, ceasing said test and recording the battery recovery voltage V R after a predetermined recovery time, calculating the battery rating R according to the formula:
  • V L f (V L , V R , C, T) where C is the battery's cold current cranking rating (CCA) and, T is the temperature of the battery and categorizing the condition of the battery based on the values of V R and R.
  • C the battery's cold current cranking rating
  • T the temperature of the battery and categorizing the condition of the battery based on the values of V R and R.
  • C is the battery's cold current cranking rating (CCA) and,
  • T is the temperature of the battery
  • said microprocessor being programmed to direct charging of said battery so as to condition said battery for further testing when a predetermined battery rating is calculated and the battery recovery voltage is below a predetermined value.
  • the invention rests upon a discovery concerning the charging of automotive batteries and is directed at enabling the heavy current discharge method of testing to be utilised with batteries in such a low state of charge that they would not otherwise be testable by that method. It has been found that a battery in a low state of charge may be "conditioned" to render it suitable for a heavy current discharge test by the application of a measured amount of charge in the order of 10% of the battery's capacity in a period of time of a few minutes.
  • conditioning is that the way in which the battery responds to the voltage, current and time sequences yields information which is of value in conjunction with a subsequent high rate discharge test, or may reveal battery states which would cause the battery to fail such a test.
  • the ability of the tester comprising conditioning and high rate discharge is extended to batteries which have initial voltages as low as 8 volts. Previous testers which utilise discharge and charge sequences have not been based upon, nor have expressed any awareness of, these principles.
  • FIGURE 1 is a simplified circuit block diagram of a heavy current battery tester according to the invention
  • FIGURE 2 is a more detailed circuit block diagram of the tester shown in FIGURE 1
  • FIGURE 3 is a flowchart of the program of a microprocessor of the tester of FIGURES 1 and 2.
  • the tester comprises essentially a heavy current tester 10, a flat battery conditioner 11 and a microprocessor 12 containing an algorithm for classifying the battery 13 according to predetermined empirical formulas.
  • the heavy current tester 10 and conditioner 11 are connected in parallel to the battery 13 as shown and each is connected to provide information to and receive information from the microprocessor 12.
  • the algorithm contained in the microprocessor 12 classifies batteries according to formulas which have been established on the basis of tests involving a range of sizes of new and used batteries at various states of charge and the algorithm in particular directs the conditioning of a battery to make it testable at voltages heretofore considered too low.
  • An important advantage of the method and apparatus according to this invention is that in relation to the heavy current testing of batteries in a low state of charge they are not left in a weaker condition after testing than they were in before testing. There is therefore less risk that the operator of the tester will be accused by a customer of having damaged his or her battery by performing the test.
  • the tester has three main stages; viz. a high power stage 14 in which heavy current testing and flat battery conditioning are performed; a control section 15 which directs the testing procedure and computes the battery condition; and a communication section 16 which enables data to be entered by the user and displays instructions and results.
  • the battery 13 to be tested is connected to a load resistor 17 by means of a switch 18.
  • the load resistor 17 and switch 18 together with thermal and overcurrent protection circuitry 22 essentially make up the heavy current tester 10 of Figure 1.
  • the switch 18 may be a semiconductor type or an electromechanical type depending upon cost.
  • the flat battery conditioner 11 which supplies a controlled charge to batteries which are too low in voltage for the load test to be immediately applied.
  • the battery terminal voltage, battery temperature and the current supplied by the conditioner are measured by measurement circuits 19 and for protection purposes temperatures of the load and solid state switch are also measured by circuits 19.
  • the microprocessor 12 receives information from the measurement circuits 19 and from a keypad which is part of display and keypad 20 and supplies control signals to the flat battery conditioner 11 and to the solid state switch 18 and data to a display which is part of the display and keypad 20.
  • the display and the keypad 20 are mounted on the front panel of the instrument and are the means whereby the user is given instructions and information and the results of the tests and is enabled to enter data into the tester.
  • serial interface circuits 21 the tester can output its results to a printer and a computer and can also be controlled from a computer (not shown). The procedure in the use of the tester is as follows.
  • testing program which is contained within the microprocessor 12 are as follows, with reference to the flowchart given in FIGURE 3. (i) Commencing with "Start” box 30 the first actions of the testing program are to measure the battery's open circuit voltage (box 31) and from that measurement to decide whether the battery is flat and needs a conditioning charge or whether it is of a high enough voltage to proceed with a heavy current load test.
  • the heavy current load test (box 32) is immediately applied for a duration of 5 seconds.
  • the load 17 is a 20 milli-ohm (approx) stainless steel resistor and the current which is drawn from the battery is in the range 300 to 500 Amps depending upon the size of the battery.
  • the voltage drop across the switch, the resistance of the leads and wiring and the internal resistance of the battery (which varies in the range from a few milli-ohms to about 10 milli-ohms according to size and condition of the battery) determine the actual current.
  • V R is the recovery voltage after the 30 second rest period
  • C is the battery's cold current cranking rating
  • T is the temperature of the battery in degrees C. More specifically the rating R is calculated according to the formula: R - V L + 14.844 - 1.6114V. - 8.888 x 10- 3 C - 2.378 x 10" 2 T + 1.913 x 10 '6 C 2 + 1.498 x 10 "5 CT + 1.245 x 10 "4 T 2
  • the rating R is devised so that it has a value of zero for a perfect battery and is negative for deteriorated batteries.
  • a battery with a rating greater than -0.5 Volt is a good battery; a battery between -1 Volt and -0.5 Volt probably has some deterioration but is still good; a battery between - 1.5 V and -1.0 V is probably a bad battery; and a battery with a rating of less than -1.5 V is definitely a bad battery.
  • the battery has a corrected recovery voltage greater than 12.1 V the R-rating is accepted, that is, the battery is good if R is greater than -1 V and the display will show a message "Good battery” (box 35) and the battery is bad if R is less than -1 V and the display will show a message "Bad battery, replace” (box 36). This is the end of the test in these cases.
  • the battery has a corrected recovery voltage less than 12.1 V and a rating R greater than -1 V it is considered to be good but in need of charging, and the display will show a message "Good battery, recharge”(box 37).
  • the type of battery distinguished by this process is one which has an acceptable loaded voltage at the end of the 5 second load test, although its corrected recovery voltage is somewhat low. In this case this is also the end of the test.
  • the battery has a corrected recovery voltage less than 12.1 V and a rating R less than -1 V it has both low loaded voltage and low recovery voltage but is not necessarily bad because it was just above the 12.1 V when the initial assessment to give a load test was made. It may therefore be flat enough to warrant conditioning in order to properly assess it.
  • the conditioning process (box 38) is commenced and the display shows a message "Conditioning battery, test may take 15 minutes”. (i ⁇ ) If the battery open circuit voltage V,,,. measured at (i) is less than 12.1 V, or the conditioning decision is reached as in (ii), the microprocessor switches on the conditioning circuit and controls the delivery of the appropriate amount of charge to make the battery reliably testable in the minimum time.
  • a conditioning time of about 18 minutes is based on a charging current of about 40 Amps (because that is the highest current from an economical transformer in the present embodiment). However a considerably greater charging current could be used and would result in reduced conditioning time.
  • monitoring of the battery's reaction to the charging current is carried out to decide whether the battery is bad and no further attempt should be made to charge it, such as due to irreversible sulphation or to shorted cells, or that it cannot reach a testable condition in reasonable time, such as 18-20 minutes, and should therefore be given an extended charge.
  • the conditioning process starts with a voltage of about 19 V, which voltage is reduced to 14.5 volts when the current rises to about 10 amps. If the current will not rise to 10 amps within 5 minutes, the battery is deemed to be too sulphated and it is rejected as bad (box 40). Furthermore, if the current rises to 10 amps with the high voltage but fails to rise to 5 amps within the remainder of the 5 minute period from the commencement of the conditioning when the voltage is reduced, it is also deemed to be bad (box 40). If the currents exceed the 10 amp and 5 amp levels in the five minute period, and the initial voltage was greater than 12.1 V, then the battery is considered suitable for conditioning with 6 A-h of charge (box 41) followed by a subsequent high rate discharge test (box 42).
  • the conditioning is abandoned and the battery is deemed too flat to test and the message "Give extended charge and retest" is displayed and the program moves to box 43. If the battery passes this assessment stage as to the degree to which it can accept charge for the high rate discharge test, the conditioning continues.
  • the actual current which flows from the charging circuit depends upon the battery internal resistance and if this is relatively high, such as 20 milli-ohms, the current is reduced and the time to deliver the charge of say 6 Amp-hours to make the battery testable is increased.
  • the microprocessor monitors the current and predicts whether the necessary charge can be delivered within a reasonable time, such as 15 minutes (box 49). If it is not possible to deliver the charge in the short time the conditioning is discontinued and the display shows a message such as "Give extended charge and retest" and the program moves to box 44. If the necessary charge such as 6 Amp-hours can be given within the time limit the conditioning continues. At the end of the conditioning the heavy current load test as described above (box 42) is immediately applied, i.e.
  • the tester of the present invention incorporates an intelligent, microprocessor controlled, conditioning process which enables batteries in a low state of charge, generally called flat batteries, to be tested by the heavy current load method in a relatively short space of time.
  • the tester conditions a battery in a low state of charge to make it testable by the heavy current load method by giving it a charge of about 10% of its capacity
  • the tester applies a heavy current discharge for a few seconds
  • the tester incorporates a temperature sensor in a battery clip and automatically makes corrections for battery temperature. Also it incorporates a state of charge correction using the recovery voltage and the corrected recovery voltage. The tester further incorporates a battery size (CCA) correction and is also able to reject batteries which have shorted cells so that they are not mistaken for batteries in a low state of charge.
  • CCA battery size
  • the tester incorporates an algorithm which uses formulas developed from hundreds of tests upon automotive batteries of various sizes, states of health ranging from new to unserviceable, temperatures ranging from -18°C to 50°C and states of charge ranging from 20% to fully charged.
  • the tester increases the convenience and usefulness of the heavy current load test.

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  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Tests Of Electric Status Of Batteries (AREA)
  • Secondary Cells (AREA)

Abstract

Un dispositif de contrôle d'une batterie à courant fort (13) comprend un moyen de décharge (17) et un conditionneur de batterie déchargée (11) que l'on branche sur celle-ci. Des circuits de mesure (19) fournissent à un microprocesseur (12) des informations sur la tension aux bornes, la température et le courant de charge de la batterie. Un procédé permettant de contrôler une batterie consiste à mesurer la tension de sortie de la batterie et ainsi à déterminer si la batterie est suffisamment chargée pour permettre l'exécution d'un contrôle valable de décharge à courant fort. Dans l'affirmative, le contrôle est réalisé avec ledit moyen de décharge afin d'absorber entre environ 300 et 500 ampères pendant 5 secondes. On enregistre les tensions de la batterie pendant le contrôle et quelque temps après, et le microprocesseur évalue l'état de la batterie comme bon ou mauvais. Le terme mauvais signifie qu'une recharge est nécessaire ainsi qu'un conditionnement afin de réaliser un contrôle valable. L'évaluation de la batterie (R) est effectuée à l'aide d'une formule empirique basée sur des données de batterie connues et sur les paramètres mesurés pendant ledit contrôle de décharge. Le conditionnement de la batterie consiste à contrôler la batterie afin de détecter des accumulateurs en court-circuit, un faible taux de charge, une sulfatation irréversible pendant le conditionnement, et à évaluer l'état de la batterie comme mauvais, ou nécessitant une charge prolongée avant l'exécution d'un nouveau contrôle, selon le cas. Si le conditionnement peut être mené à bien, on réalise un contrôle de décharge à courant fort et on détermine l'évaluation de la batterie (R).
PCT/AU1992/000055 1991-02-13 1992-02-13 Controle des batteries a courant fort WO1992015022A1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AU12461/92A AU652029B2 (en) 1991-02-13 1992-02-13 Testing heavy current batteries

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
AUPK4590 1991-02-13
AUPK459091 1991-02-13

Publications (1)

Publication Number Publication Date
WO1992015022A1 true WO1992015022A1 (fr) 1992-09-03

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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2000057199A1 (fr) * 1999-03-22 2000-09-28 Johnson Controls Technology Company Procede et appareil destines a determiner l'etat de charge d'une batterie
US8947050B2 (en) 2010-03-11 2015-02-03 Ford Global Technologies, Llc Charging of vehicle battery based on indicators of impedance and health
US9753093B2 (en) 2010-03-11 2017-09-05 Ford Global Technologies, Llc Vehicle and method of diagnosing battery condition of same

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS56126776A (en) * 1980-03-10 1981-10-05 Toyota Motor Corp Detecting method for capacity of battery for automobile
JPS56126777A (en) * 1980-03-10 1981-10-05 Toyota Motor Corp Detecting method for capacity of battery for automobile
WO1983002005A1 (fr) * 1981-12-04 1983-06-09 Bear Automative Service Equipm Appareil de controle d'une batterie d'un vehicule automobile
EP0323539A1 (fr) * 1988-01-08 1989-07-12 RAMOT UNIVERSITY, AUTHORITY FOR APPLIED RESEARCH & INDUSTRIAL DEVELOPMENT LTD. Méthode pour déterminer l'état de charge de batteries, notamment de batteries lithium
WO1990001221A1 (fr) * 1988-07-27 1990-02-08 Gnb Incorporated Dispositif de controle pour batterie electrique et sa configuration
AU4388289A (en) * 1989-03-31 1990-10-04 Mitsubishi Denki Kabushiki Kaisha Cognition device for battery residual capacity
SU1619360A1 (ru) * 1988-02-10 1991-01-07 Ереванский политехнический институт им.К.Маркса Способ определени остаточной емкости кислотной свинцовой аккумул торной батареи и устройство дл его осуществлени
WO1991008494A1 (fr) * 1988-07-21 1991-06-13 Opalport Electronics Limited Systeme pour contrôler les batteries

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS56126776A (en) * 1980-03-10 1981-10-05 Toyota Motor Corp Detecting method for capacity of battery for automobile
JPS56126777A (en) * 1980-03-10 1981-10-05 Toyota Motor Corp Detecting method for capacity of battery for automobile
WO1983002005A1 (fr) * 1981-12-04 1983-06-09 Bear Automative Service Equipm Appareil de controle d'une batterie d'un vehicule automobile
EP0323539A1 (fr) * 1988-01-08 1989-07-12 RAMOT UNIVERSITY, AUTHORITY FOR APPLIED RESEARCH & INDUSTRIAL DEVELOPMENT LTD. Méthode pour déterminer l'état de charge de batteries, notamment de batteries lithium
SU1619360A1 (ru) * 1988-02-10 1991-01-07 Ереванский политехнический институт им.К.Маркса Способ определени остаточной емкости кислотной свинцовой аккумул торной батареи и устройство дл его осуществлени
WO1991008494A1 (fr) * 1988-07-21 1991-06-13 Opalport Electronics Limited Systeme pour contrôler les batteries
WO1990001221A1 (fr) * 1988-07-27 1990-02-08 Gnb Incorporated Dispositif de controle pour batterie electrique et sa configuration
AU4388289A (en) * 1989-03-31 1990-10-04 Mitsubishi Denki Kabushiki Kaisha Cognition device for battery residual capacity

Non-Patent Citations (3)

* Cited by examiner, † Cited by third party
Title
DERWENT ABSTRACT, Accession No. 91-272997/37, class S01; & SU,A,1 619 360 (EREV POLY), 7 January 1991. *
PATENT ABSTRACTS OF JAPAN, P-96, page 10; & JP,A,56 126 776 (TOYOTA JIDOSHA KOGYO K.K.), 5 October 1981. *
PATENT ABSTRACTS OF JAPAN, P-96, page 10; & JP,A,56 126 777 (TOYOTA JIDOSHA KOGYO K.K.), 5 October 1981. *

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2000057199A1 (fr) * 1999-03-22 2000-09-28 Johnson Controls Technology Company Procede et appareil destines a determiner l'etat de charge d'une batterie
US6144185A (en) * 1999-03-22 2000-11-07 Johnson Controls Technology Company Method and apparatus for determining the condition of a battery through the use of multiple battery tests
US8947050B2 (en) 2010-03-11 2015-02-03 Ford Global Technologies, Llc Charging of vehicle battery based on indicators of impedance and health
US9753093B2 (en) 2010-03-11 2017-09-05 Ford Global Technologies, Llc Vehicle and method of diagnosing battery condition of same

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