SIST EN 50342-1:2006

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.Lead-acid starter batteries -- Part 1: General requirements and methods of testBatteries d'accumulateurs de dmarrage au plomb -- Partie 1: Prescriptions gnrales et mthodes d'essaisBlei-Akkumulatoren-Starterbatterien -- Teil 1: Allgemeine Anforderungen und PrfungenTa slovenski standard je istoveten z:EN 50342-1:2006SIST EN 50342-1:2006en29.220.20ICS:SIST EN 50342:2002/A3:2005SIST EN 50342:2002/A2:2002SIST EN 50342:2002 + A1:20021DGRPHãþDSLOVENSKI
STANDARDSIST EN 50342-1:200601-julij-2006







EUROPEAN STANDARD EN 50342-1 NORME EUROPÉENNE
EUROPÄISCHE NORM April 2006
CENELEC European Committee for Electrotechnical Standardization Comité Européen de Normalisation Electrotechnique Europäisches Komitee für Elektrotechnische Normung
Central Secretariat: rue de Stassart 35, B - 1050 Brussels
© 2006 CENELEC -
All rights of exploitation in any form and by any means reserved worldwide for CENELEC members.
Ref. No. EN 50342-1:2006 E
ICS 01.080.20; 29.220.20 Supersedes EN 50342:2001 + A1:2001 + A2:2001 + A3:2004
English version
Lead-acid starter batteries Part 1: General requirements and methods of test
Batteries d'accumulateurs
de démarrage au plomb Partie 1: Prescriptions générales
et méthodes d'essais
Blei-Akkumulatoren-Starterbatterien Teil 1: Allgemeine Anforderungen
und Prüfungen
This European Standard was approved by CENELEC on 2004-12-01. CENELEC members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration.
Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the Central Secretariat or to any CENELEC member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by translation under the responsibility of a CENELEC member into its own language and notified to the Central Secretariat has the same status as the official versions.
CENELEC members are the national electrotechnical committees of Austria, Belgium, Cyprus, the Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and the United Kingdom.



EN 50342-1:2006 - 2 - Foreword This European Standard was prepared by the Technical Committee CENELEC TC 21X, Secondary cells and batteries. A draft amendment (prA4) to EN 50342:2001 was submitted to the Unique Acceptance Procedure and was approved by CENELEC on 2004-12-01 to be combined with the existing documents and published as EN 50342-1. This European Standard supersedes EN 50342:2001 + A1:2001 + A2:2001 + corrigendum March 2003 + A3:2004 and is the result of a detailed review of the existing documents resulting in a series of changes of an editorial nature designed to make it more clearly defined and consistent.
Annex A of EN 50342:2001, which described the European Type Number for starter batteries (ETN), was removed due to the cessation of its operation by an external company. The following dates were fixed: – latest date by which the EN has to be implemented
at national level by publication of an identical
national standard or by endorsement
(dop)
2006-11-01 – latest date by which the national standards conflicting
with the EN have to be withdrawn
(dow)
2007-12-01 __________



- 3 - EN 50342-1:2006 Contents Clause Page 1 General.4 1.1 Scope.4 1.2 Object.4 1.3 Designation of starter batteries - Electrolyte density and open circuit voltage.4 1.4 Condition on delivery.5 2 General requirements.5 2.1 Identification, labelling.5 2.2 Marking of the polarity.5 2.3 Additional designation.6 3 Functional characteristics.6 3.1 Electrical characteristics.6 3.2 Mechanical characteristics.7 4 General test conditions.7 4.1 Sampling of batteries.7 4.2 Preparation of batteries prior to test - Definition of a fully-charged battery.7 4.3 Activation of dry-charged batteries.8 4.4 Measuring instruments.8 4.5 Test sequence.9 5 Tests/methods and requirements.10 5.1 20 hour capacity check Ce.10 5.2 Reserve capacity check Cr,e.10 5.3 Cranking performance test.10 5.4 Charge acceptance test.11 5.5 Charge retention test.12 5.6 Endurance tests for vented batteries.12 5.7 Endurance tests for VRLA batteries.16 5.8 Water consumption test.19 5.9 Vibration resistance test.20 5.10 Electrolyte retention test.21 5.11 Cranking performance for dry-charged batteries after activation.21 Annex A
(normative) - Safety labelling – Definition of the six coloured symbols.22 Annex B
(normative) - Correlation between Cn and Cr,n.23 Annex C
(normative) - Normative references.24
Figure A.1 – Coloured symbols.22 Figure A.2 – Symbol dimensions.22
Table 1 – Test sequence.9 Table 2 – Charging voltages.14 Table 3 – Vibration resistance test.21



EN 50342-1:2006 - 4 - 1 General 1.1 Scope This standard is applicable to lead-acid batteries with a nominal voltage of 12 V, used primarily as a power source for the starting of internal combustion engines, lighting and also for auxiliary equipment of internal combustion engine vehicles. These batteries are commonly called "starter batteries". Batteries with a nominal voltage of 6 V are also included within the scope of this standard. All referenced voltages have to be divided by two for 6 V batteries. This standard is applicable to batteries for the following purposes: − batteries for passenger cars, − batteries for commercial and industrial vehicles for normal use, − batteries for commercial and industrial vehicles for severe use. This standard is not applicable to batteries for other purposes, for example the starting of railcar internal combustion engines. 1.2 Object The object of this standard is to specify − general requirements; − certain essential functional characteristics, the relevant test methods and results required, for several classes and types of starter batteries. 1.3 Designation of starter batteries - Electrolyte density and open circuit voltage 1.3.1 Batteries are classified according to their types − vented (flooded) battery: a secondary battery having a cover provided with one or more openings through which gaseous products may escape; − valve regulated (with gas recombination) battery (VRLA): a secondary battery which is closed under normal conditions but which has an arrangement that allows the escape of gas if the internal pressure exceeds a predetermined value. The battery cannot receive addition to the electrolyte. In this type of battery, the electrolyte is immobilised. 1.3.2 Electrolyte density and open circuit voltage The density of the electrolyte in all fully charged vented batteries shall be in the range 1,27 kg/l to 1,30 kg/l at 25 °C unless otherwise specified by the manufacturer. The open circuit voltage (OCV), of fully charged batteries after a minimum 24 h stand on open circuit, shall be in the range 12,70 V to 12,90 V for vented types and 12,80 V minimum for valve regulated types at 25 °C unless otherwise specified by the manufacturer. The manufacturer shall specify the electrolyte density (or OCV) and tolerance. If such information is not available, vented battery testing shall be carried out with a density of 1,28 kg/l ± 0,01 kg/l at 25 °C or an OCV of 12,76 V ± 0,06 V at 25 °C and valve regulated battery testing shall be carried out with a minimum OCV of 12,80 V.



- 5 - EN 50342-1:2006 1.4 Condition on delivery New vented batteries may be supplied − either in a state ready for use, filled with the appropriate electrolyte to the maximum level. After an initial charge (according to 4.2.1), the electrolyte density or OCV shall be within the ranges specified in 1.3; − or in a dry-charged state not filled with electrolyte. The density of the acid to fill such batteries before use shall be in the range 1,27 kg/l to 1,30 kg/l at 25 °C unless otherwise specified by the manufacturer. Valve regulated batteries are normally supplied in a state ready for use. For these batteries the electrolyte is not accessible and therefore its density cannot be checked. 2 General requirements 2.1 Identification, labelling Batteries according to this standard shall bear the following characteristics on at least one of their sides or on the top surface: a) the identification of manufacturer or supplier; b) the nominal voltage, i.e. 12 V or 6 V; c) the capacity: − either nominal capacity Cn (Ah) (see 3.1.2), − or nominal reserve capacity Cr,n (min) (see 3.1.2), The values of Cn or Cr,n for all batteries shall correspond to the electrolyte density or OCV given in 1.3; d) the nominal cranking current Icc (see 3.1.1); e) the six coloured symbols as specified in Annex A, Safety labelling; f)
the marking for the separate collection and recycling according to EN 61429; g) valve regulated batteries shall be marked ‘VRLA'. NOTE
Batteries may be marked with other information such as the filling and charging date (see 4.1). 2.2 Marking of the polarity This shall be in accordance with: EN 60095-2 Part 2: Dimensions of batteries and dimensions and marking of terminals EN 60095-4 Part 4: Dimensions of batteries for heavy commercial vehicles



EN 50342-1:2006 - 6 - 2.3 Additional designation Vented starter batteries may be designated as "low water loss" or "very low water loss" according to this European Standard if they comply with the corresponding requirements of 5.8.1 and the requirement in 5.5.2. 3 Functional characteristics For general definitions of terms see Part 482 of the International Electrotechnical Vocabulary (IEV) (IEC 60050-482). 3.1 Electrical characteristics 3.1.1 The cranking current is the discharge current Icc to be indicated by the manufacturer which a battery can supply at –18 °C for 10 s to a minimum voltage Uf = 7,50 V and complying with requirements of 5.3. 3.1.2 The capacity of a starter battery is defined for the temperature of 25 °C ± 2 °C. It may be indicated by the manufacturer either as − nominal capacity Cn (Ah), or as − nominal reserve capacity Cr,n (min). The nominal 20 hour capacity Cn is the electric charge (in Ah) that a battery can supply with a current: 20nnCI= (A) to a final voltage Uf = 10,50 V. The effective capacity Ce shall be determined by discharging a battery with constant current In to Uf = 10,50 V (see 5.1). The nominal reserve capacity Cr,n is the time (in minutes) that a battery can maintain a discharge of 25 A to a cut-off voltage Uf = 10,50 V. The effective reserve capacity Cr,e shall be determined by discharging a battery with the constant current I = 25 A to Uf = 10,50 V (see 5.2). NOTE
For the correlation (relationship) of Cn and Cr,n, see Annex B. 3.1.3 The charge acceptance is expressed as the current Ica which a partially discharged battery accepts at 0 °C and a constant voltage of 14,40 V (see 5.4). 3.1.4 Charge retention is measured by the cold cranking performance of the charged and filled battery after storage on open circuit under defined conditions (temperature, time - see 5.5).



- 7 - EN 50342-1:2006 3.1.5 The endurance test consists of two parts 3.1.5.1 Corrosion test represents the ability of a battery to perform repeated overcharge/storage periods (see 5.6 and 5.7). 3.1.5.2 Cycling test represents the ability of a battery to perform repeated discharge/recharge cycles and long rest periods on open circuit. This ability shall be tested by a series of cycles and rest periods under specified conditions after which the cold cranking performance shall be determined (see 5.6 and 5.7). 3.1.6 Water consumption is defined as g/Ah Ce or g/min Cr,e (see 3.1.2 and 5.8). Valve regulated batteries have a very low water consumption and are not intended to receive addition to the electrolyte (see 5.8.2). 3.1.7 Dry-charged battery: A new battery may be designated as dry-charged if it can be activated -ready for service- by filling it with the defined electrolyte (see 1.3 and 1.4) and in accordance with any specific instructions from the manufacturer and if it then conforms to the requirements of 5.11. 3.2 Mechanical characteristics 3.2.1 Vibration resistance represents the ability of a battery to maintain service under acceleration forces. Requirements are verified by the test defined in 5.9. 3.2.2 Electrolyte retention is the ability of a battery to retain electrolyte under specified mechanical conditions (see 5.10). Valve regulated batteries are submitted to a special test (see 5.10.2). 4 General test conditions 4.1 Sampling of batteries All tests shall be carried out on new battery samples. Samples shall be considered as new no later than − 30 days after the acid filling and formation date in the case of filled and charged batteries, − 60 days after shipment date of the manufacturer in the case of dry-charged batteries. 4.2 Preparation of batteries prior to test - Definition of a fully-charged battery All tests, except that in 5.11, shall commence with fully-charged batteries. Batteries shall be considered as fully-charged if they have undergone the charging procedures of 4.2.1 for vented batteries or 4.2.2 for valve regulated batteries. 4.2.1 Charging of vented batteries The battery shall be charged at a voltage of 16,00 V ± 0,10 V for 24 h with the maximum current limited to 5 In (see 3.1.2). The battery temperature shall be maintained in the range 25 °C to 35 °C. If necessary, an appropriate environmental control system shall be used, e.g. a water bath. In the case of recharging after a test for cranking performance (according to 5.3) the charging time may be limited to 16 h.



EN 50342-1:2006 - 8 - 4.2.2 Charging of valve regulated batteries Unless otherwise recommended by the manufacturer, the battery shall be charged − at a constant voltage of 14,40 V ± 0,01 V for 20 h with the maximum current limited to 5 In (see 3.1.2), and − then with a constant current of 0,5 In for 4 h. The temperature shall be maintained in the range 25 °C to 35 °C. If necessary an appropriate environmental control system shall be used, e.g. a water bath. 4.3 Activation of dry-charged batteries Dry-charged batteries shall be filled with the defined electrolyte (according to 1.4) to the maximum level indicated by internal or external marks or according to the manufacturer's activation instructions. Any additional manufacturer's recommended activation instructions shall be complied with. 4.4 Measuring instruments 4.4.1 Electrical measuring instruments The range of instruments used shall be appropriate for the magnitude of the voltage or current to be measured. – Voltage measurement The instruments used for measuring voltages shall be digital voltmeters having an accuracy of ± 0,04 V or better.
– Current measurement The instruments used for current measurement shall be digital ammeters having an accuracy of 1,0 % or better. The assembly of ammeter, shunt and leads shall have an overall accuracy of 1,0 % or better. 4.4.2 Temperature measurement The thermometers used for measuring temperatures shall have an appropriate range, and the value of each scale division shall not be greater than 1 K. The accuracy of the calibration of the instruments shall be not less than 0,5 K. 4.4.3 Density measurement The density of the electrolyte shall be measured with hydrometers furnished with a graduated scale, the value of each division of which is equal at most to 0,005 kg/l. The accuracy of calibration shall be to 0,005 kg/l or better. 4.4.4 Time measurement The instruments used for measuring time shall be graduated in hours, minutes and seconds. They shall have an accuracy of at least ± 1 %.



- 9 - EN 50342-1:2006 4.5 Test sequence 4.5.1 Batteries filled and charged Initially the batteries are subjected to the following series of tests: 1st
Ce or Cr,e check, 1st
cranking performance test; 2nd
Ce or Cr,e check, 2nd
cranking performance test; 3rd
Ce or Cr,e check, 3rd
cranking performance test. For Ce or Cr,e and the cranking performance the specified values shall be met in at least one of the relevant discharges above. NOTE
It is not necessary to complete the sequence if the specified values are achieved on the first or second test other than for batteries that will subsequently be tested for charge acceptance. If, and only if, the initial capacity and cranking tests are successful, the batteries shall be tested in accordance with the remainder of the test sequence given in Table 1. These tests shall commence not later than one week after completion of the initial tests. Table 1 – Test sequence Battery Subclause 1 2 3 4 5 6 1st Ce or Cr,e 5.1 or 5.2 X X X X X X 1st cranking performance test 5.3 X X X X X X 2nd Ce or Cr,e 5.1 or 5.2 (X) (X) (X) X (X) (X) 2nd cranking performance test 5.3 (X) (X) (X) X (X) (X) 3rd Ce or Cr,e 5.1 or 5.2 (X) (X) (X) X (X) (X) 3rd cranking performance test 5.3 (X) (X) (X) X (X) (X) Endurance
Corrosion 5.6 or 5.7 X
Endurance
Cycling 5.6 or 5.7
X
Charge retention 5.5
X
Charge acceptance 5.4
X
Electrolyte retention 5.10
X
Vibration resistance 5.9
X
Water consumption a 5.8
X a The test for water consumption should be applied only to “low water loss” and “very low water loss” vented batteries according to 2.3 and to valve regulated batteries. NOTE (X) denotes that this test needs to be carried out if the previous same test did not achieve the required levels.



EN 50342-1:2006 - 10 - 4.5.2 Dry-charged batteries − Initial cranking performance after activation (see 5.11). − Capacity test (see 5.1) or reserve capacity test (see 5.2). − Subsequent testing following the sequence defined in 4.5.1. 5 Tests/methods and requirements 5.1 20 hour capacity check Ce 5.1.1 Throughout the duration of the tests, the battery shall be placed in a water bath maintained at a temperature of 25 °C ± 2 °C. The terminal base of the battery shall be at least 15 mm but not more than 25 mm above the level of the water. If several batteries are in the same water bath then the distance between them and also the distance to the walls of the bath shall be at least 25 mm. 5.1.2 The battery shall be discharged with the current In (calculated according to 3.1.2) kept constant at ± 2 % of the nominal value until the terminal voltage falls to 10,50 V ± 0,05 V. The duration t (h) of this discharge shall be recorded. The beginning of the discharge shall take place within a period of 1 h to 5 h from the time of the end of charging. 5.1.3 The capacity Ce is Ce = t x In (Ah). 5.2 Reserve capacity check Cr,e 5.2.1 The battery shall be placed in a water bath according to 5.1.1. 5.2.2 Within a 1 h to 5 h period after the end of charging according to 4.2, the battery shall be discharged with a current of 25 A ± 1 % until the terminal voltage falls to 10,50 V ± 0,05 V. The duration t(min) of the discharge shall be recorded. 5.2.3 The reserve capacity Cr,e is Cr,e = t (min). 5.3 Cranking performance test 5.3.1 After a rest period of up to 24 h after preparation according to 4.2, the battery shall be placed in a cooling chamber with (forced) air circulation at a temperature of -18 °C ± 1 °C until the temperature of the middle cells has reached -18 °C ± 1 °C. NOTE
It is generally accepted that the required temperature will be achieved after a minimum period of 24 h in the cooling chamber. 5.3.2 The battery shall then be discharged, either within or outside the cooling chamber, within 2 min after the end of the cooling period with a current Icc (see 3.1.1). This current shall be kept constant to within ± 0,5 % during the discharge. 5.3.3 After 10 s discharge, the terminal voltage Uf shall be recorded and the current shall be cut off. The voltage Uf shall be not less than 7,50 V. NOTE
Subclauses 5.3.1 to 5.3.3 comprise stage 1 of the cranking performance test. 5.3.4 The test shall be continued after a rest time of 10 s ± 1 s.



- 11 - EN 50342-1:2006 5.3.5 The battery shall then be discharged at 0,6 Icc. The current shall be kept constant to within ± 0,5 % during the discharge. The discharge shall be terminated when the battery voltage reaches 6 V. The discharge time (t'6v) at 0,6 Icc to 6 V shall be recorded in seconds. NOTE
Subclause 5.3.5 comprises stage 2 of the test. 5.3.6 The discharge time (t'6v) may be used to define the cold cranking capacity (C'cc) in stage 2 in ampere hours in the following equation: CCVCCIxtC6,03600''6= The total cold cranking capacity Ccc given by stage 1 plus stage 2 is given by the following equation: CCCCCCCIC'360010+×= i.e. ()VCCCCtIC6'6,0103600+= 5.3.7 t6v is defined as the duration of the second stage (t’6v) plus the equivalent duration of the first stage discharge if run at 0,6 Icc, i.e. it is given, in seconds, by the following equation: 17'6,010'666+=+=vvvttt 5.3.8 According to battery use, the battery shall comply with the following, as applicable: Requirement 1 t6v ≥ 90 s. Requirement 2 The cold cranking capacity Ccc (see 5.3.6) shall be ≥ 0,2 Cn (alternatively ≥ 0,12 Cr,n). NOTE
This requirement is regarded as fulfilled for batteries giving a discharge time t6v ≥ 150 s. 5.4 Charge acceptance test 5.4.1 The battery shall be discharged at a temperature of 25 °C ± 2 °C at a current IO for 5 h where: 10eoCI= (A) The value Ce shall − either be taken as the maximum value Ce of the previous discharges according to 5.1; − or be calculated from the maximum value Cr,n of the previous discharge(s) according to 5.2 using the correlation formula in Annex B.



EN 50342-1:2006 - 12 - 5.4.2 Within 10 min after the discharge, the battery shall be placed in a cooling chamber with (forced) air circulation at a temperature of 0 °C ± 1 °C until the temperature of the middle cells is 0 °C ± 1 °C. NOTE
It is generally accepted that the required temperature will be achieved after a minimum period of 15 h in the cooling chamber. 5.4.3 At this temperature, the battery shall be charged at a constant voltage of 14,40 V ± 0,05 V. After 10 min, the charging current Ica shall be recorded. 5.4.4 Ica shall be: vented batteries: ≥ 2 I0 valve regulated batteries: requirement 1 ≥ Io
requirement 2 ≥ 2 Io 5.5 Charge retention test 5.5.1 Requirement for "normal water loss" vented batteries 5.5.1.1 A fully-charged battery (according to 4.2) with its vent plugs firmly in place and with clean and dry surfaces shall be stored in a dry atmosphere at 40 °C ± 2 °C for 21 days on open circuit. No connecting clamps or cables shall be attached to the terminals. 5.5.1.2 After this storage period the battery shall be submitted, without recharge, to a cold cranking performance test according to 5.3.1 and 5.3.5. The voltage after 30 s of discharge shall be not less than 8,00 V. 5.5.2 Requirements for "low water loss" and "very low water loss" vented batteries and valve regulated batteries Under the same conditions as in 5.5.1 the voltage after 30 s of discharge shall be not less than 8,50 V. 5.6 Endurance tests for vented batteries 5.6.1 Batteries shall be tested in accordance with 5.6.2, 5.6.3 or 5.6.4, as applicable according to the intended battery use. 5.6.2 Requirement 1 5.6.2.1 Corrosion test 5.6.2.1.1 The test shall be carried out on fully charged batteries in accordance with 4.2.1. 5.6.2.1.2 The battery shall be placed in a water bath maintained at a temperature of 60 °C ± 2 °C. The terminal base of the battery shall be at least 15 mm but not more than 25 mm above the level of the water. If several batteries are in the same water bath then the distance between them and also the distance to the walls of the bath shall be at least 25 mm.
5.6.2.1.3 The battery, maintained at 60 °C ± 2 °C, shall be charged at a constant voltage of
14,00 V ± 0,10 V, for a period of 13 days. 5.6.2.1.4 The battery shall be stored on open circuit, still at 60 °C ± 2 °C, for a period of 13 days. No connecting clamps or cables shall be attached to the terminals.



- 13 - EN 50342-1:2006 5.6.2.1.5 The battery shall be cooled to reach 25 °C ± 2 °C. Purified water shall be added as necessary to maintain electrolyte level in accordance with the manufacturer’s recommendations.
5.6.2.1.6 The battery shall then be recharged in accordance with 4.2.1. 5.6.2.1.7 The battery shall be discharged with a current of 0,6 Icc at 25 °C ± 2 °C. 5.6.2.1.8 The sequence 5.6.2.1.1 to 5.6.2.1.7 constitutes one corrosion test unit. 5.6.2.1.9 The whole sequence 5.6.2.1.1 to 5.6.2.1.7 shall be repeated and the test shall be terminated when the battery voltage reaches 6 V in less than 30 s with a current of 0,6 Icc in cranking test at 25 °C ± 2 °C. 5.6.2.1.10 The required number of corrosion test units is four. 5.6.2.2 Cycling test 5.6.2.2.1 The tests shall be carried out on fully charged batteries in accordance with 4.2.1. 5.6.2.2.2 Throughout the whole test period, with the exception of the rapid discharge test at the temperature of -18 °C ± 1 °C, the battery shall be placed in a water bath at a temperature of 25° C ± 2 °C. The terminal base of the battery shall be at least 15 mm but not more than 25 mm above the level of the water. If several batteries are in the same water bath then the distance between them and also the distance to the walls of the bath shall be at least 25 mm. 5.6.2.2.3 Purified water shall be added to the battery as necessary during the test to maintain the electrolyte level in accordance with the manufacturer’s recommendations except for "low water loss" and "very low water loss" batteries. 5.6.2.2.4 The batteries shall be connected to a device where they undergo a series of 180 cycles, each cycle comprising: a) a discharge for 1 h at a current in amperes of I = 5 In
b) immediately followed by a recharge – for 2 h and 55 min at a constant voltage of 14,80 V ± 0,05 V, the maximum current in amperes being limited to Imax = 10 In, and
– for 5 min at a current of 2,5 In. 5.6.2.2.5 The test shall be terminated when the battery voltage drops below 10,50 V during the discharge prior to completion of 180 cycles. 5.6.2.2.6 When the cycling is over, the battery shall be placed in a cooling chamber with (forced) air circulation at a temperature of -18 °C ± 1 °C for a minimum of 20 h or until the temperature in one of the middle
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