IEC 62660-2:2018
(Main)Secondary lithium-ion cells for the propulsion of electric road vehicles - Part 2: Reliability and abuse testing
Secondary lithium-ion cells for the propulsion of electric road vehicles - Part 2: Reliability and abuse testing
IEC 62660-2:2018 specifies test procedures to observe the reliability and abuse behaviour of secondary lithium-ion cells and cell blocks used for propulsion of electric vehicles including battery electric vehicles (BEV) and hybrid electric vehicles (HEV). This document specifies the standard test procedures and conditions for basic characteristics of lithium-ion cells for use in propulsion of battery and hybrid electric vehicles. The tests are indispensable for obtaining essential data on reliability and abuse behaviour of lithium-ion cells for use in various designs of battery systems and battery packs. This document provides standard classification of description of test results to be used for the design of battery systems or battery packs. IEC 62660-2:2018 cancels and replaces the first edition published in 2010. This edition constitutes a technical revision. This edition includes the following significant technical changes with respect to the previous edition:
a) The procedure of forced discharge test has been clarified (6.4.3.2).
b) "Cell block" has been added to the scope (Clause 1).
c) Option of temperature cycling test with electrical operation has been deleted (6.3.2).
d) The test conditions for overcharge test have been revised (6.4.2.2).
Eléments d'accumulateurs lithium-ion pour la propulsion des véhicules routiers électriques - Partie 2: Essais de fiabilité et de traitement abusif
L'IEC 62660-2:2018 spécifie les procédures d'essai destinées à observer la fiabilité et le comportement sous traitement abusif des éléments et des blocs d’éléments d’accumulateurs lithium-ion utilisés pour la propulsion des véhicules électriques, y compris les véhicules électriques à batterie (BEV) et les véhicules électriques hybrides (HEV). Le présent document spécifie les procédures et les conditions d'essai normalisées pour des caractéristiques fondamentales des éléments lithium-ion utilisés pour la propulsion des véhicules électriques à batterie d’accumulateurs et hybrides. Les essais sont indispensables pour obtenir des données importantes sur la fiabilité et sur le comportement sous traitement abusif des éléments lithium-ion utilisés dans différentes conceptions de systèmes de batteries et de packs de batteries. Le présent document donne une classification normalisée de la description des résultats d'essai à utiliser pour la conception des systèmes de batteries et des packs de batteries. L'IEC 62660-2:2018 annule et remplace la première édition parue en 2010. Cette édition constitue une révision technique. Cette édition inclut les modifications techniques majeures suivantes par rapport à l'édition précédente:
a) La procédure d'essai de décharge forcée a été clarifiée (6.4.3.2).
b) Le concept de "bloc d’éléments" a été ajouté au domaine d’application (Article 1).
c) L’option d’essai de cycles de température avec fonctionnement électrique a été supprimée (6.3.2).
d) Les conditions d’essai relatives à l’essai de surcharge ont été révisées (6.4.2.2).
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IEC 62660-2 ®
Edition 2.0 2018-12
REDLINE VERSION
INTERNATIONAL
STANDARD
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Secondary lithium-ion cells for the propulsion of electric road vehicles –
Part 2: Reliability and abuse testing
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IEC 62660-2 ®
Edition 2.0 2018-12
REDLINE VERSION
INTERNATIONAL
STANDARD
colour
inside
Secondary lithium-ion cells for the propulsion of electric road vehicles –
Part 2: Reliability and abuse testing
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 29.220.20; 43.120 ISBN 978-2-8322-6350-1
– 2 – IEC 62660-2:2018 RLV © IEC 2018
CONTENTS
FOREWORD . 4
INTRODUCTION . 6
1 Scope . 7
2 Normative references . 7
3 Terms and definitions . 8
4 Test conditions . 9
4.1 General . 9
4.2 Measuring instruments . 9
4.2.1 Range of measuring devices . 9
4.2.2 Voltage measurement . 9
4.2.3 Current measurement . 9
4.2.4 Temperature measurements . 9
4.2.5 Other measurements . 10
4.3 Tolerance . 10
Test temperature .
4.4 Thermal stabilization . 11
5 Electrical measurement . 11
5.1 General charge conditions . 11
5.2 Capacity . 11
5.3 SOC adjustment . 11
6 Reliability and abuse tests . 12
6.1 General . 12
6.2 Mechanical test . 12
6.2.1 Vibration . 12
6.2.2 Mechanical shock . 13
6.2.3 Crush . 14
6.3 Thermal test . 15
6.3.1 High temperature endurance. 15
6.3.2 Temperature cycling . 16
6.4 Electrical test . 19
6.4.1 External short circuit . 19
6.4.2 Overcharge . 20
6.4.3 Forced discharge . 21
7 Description of test results . 21
Annex A (informative) Selective test conditions . 22
Bibliography . 23
Figure – BEV current profile for temperature cycling .
Figure – SOC level over all test cycles – BEV application .
Figure – HEV current profile for temperature cycling .
Figure 1 – Example of temperature measurement of cell . 10
Figure 2 – PSD of acceleration vs. plotted against frequency . 13
Figure 3 – Examples of crush test . 15
Table – Temperatures and time duration for temperature cycling .
Table – Test steps and BEV current profile .
Table – Test steps and HEV current profile .
Table 1 – Discharge conditions . 11
Table 2 – Values for PSD and frequency . 13
Table 3 – Mechanical shock test – parameters . 14
Table 4 – Temperatures and time duration for temperature cycling . 16
Table 5 – Test result description . 21
Table A.1 – Capacity test conditions . 22
– 4 – IEC 62660-2:2018 RLV © IEC 2018
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
SECONDARY LITHIUM-ION CELLS FOR
THE PROPULSION OF ELECTRIC ROAD VEHICLES –
Part 2: Reliability and abuse testing
FOREWORD
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This redline version of the official IEC Standard allows the user to identify the changes
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International Standard IEC 62660-2 has been prepared by IEC technical committee 21:
Secondary cells and batteries.
This second edition cancels and replaces the first edition published in 2010. This edition
constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) The procedure of forced discharge test has been clarified (6.4.3.2).
b) "Cell block" has been added to the scope (Clause 1).
c) Option of temperature cycling test with electrical operation has been deleted (6.3.2).
d) The test conditions for overcharge test have been revised (6.4.2.2).
The text of this International Standard is based on the following documents:
FDIS Report on voting
21/976/FDIS 21/986/RVD
Full information on the voting for the approval of this International Standard can be found in
the report on voting indicated in the above table.
This document has been drafted in accordance with the ISO/IEC Directives, Part 2.
A list of all the parts in the IEC 62660 series, published under the general title Secondary
lithium-ion cells for the propulsion of electric road vehicles, can be found on the IEC website.
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under "http://webstore.iec.ch" in the data related to
the specific document. At this date, the document will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
IMPORTANT – The 'colour inside' logo on the cover page of this publication indicates
that it contains colours which are considered to be useful for the correct
understanding of its contents. Users should therefore print this document using a
colour printer.
– 6 – IEC 62660-2:2018 RLV © IEC 2018
INTRODUCTION
The commercialization of electric road vehicles including battery, hybrid and plug-in hybrid
electric vehicles has been accelerated in the global market, responding to the global concerns
on CO reduction and energy security. This, in turn, has led to rapidly increasing demand for
high-power and high-energy-density traction batteries. Lithium-ion batteries are estimated to
be one of the most promising secondary batteries for the propulsion of electric vehicles. In the
light of rapidly diffusing the rapid spread of hybrid electric vehicles and the emergence of
battery and plug-in hybrid electric vehicles, a standard method for testing reliability and abuse
requirements of lithium-ion batteries is indispensable for securing a basic level of safety and
obtaining essential data for the design of vehicle systems and battery packs.
This document specifies reliability and abuse testing for automobile traction lithium-ion cells
that basically differ from the other cells including those for portable and stationary
applications specified by other IEC standards. For automobile application, it is important to
note the usage specificity; i.e. the design diversity of automobile battery packs and systems,
and specific requirements for cells and batteries corresponding to each of such designs.
Based on these facts, the purpose of this document is to provide a basic test methodology
with general versatility, which serves a function in common primary testing of lithium-ion cells
to be used in a variety of battery systems. For the requirements for cells differ depending on
the system designs of battery pack or vehicle, and should be evaluated by the users, This
document does not provide any pass-fail criteria for the tests, but specifies a standard
classification of descriptions for test results.
This document is associated with ISO 12405-1-and ISO 12405-2 ISO 12405-4 [1] .
IEC 62660-1 [2] specifies the performance testing of lithium-ion cells for electric vehicle
application.
IEC 62660-3 [3] specifies the safety requirements of lithium-ion cells for electric vehicle
application.
___________
Numbers in square brackets refer to the Bibliography.
SECONDARY LITHIUM-ION CELLS FOR
THE PROPULSION OF ELECTRIC ROAD VEHICLES –
Part 2: Reliability and abuse testing
1 Scope
This part of IEC 62660 specifies test procedures to observe the reliability and abuse
behaviour of secondary lithium-ion cells and cell blocks used for propulsion of electric
vehicles including battery electric vehicles (BEV) and hybrid electric vehicles (HEV).
NOTE 1 Secondary lithium-ion cells used for propulsion of plug-in hybrid electric vehicles (PHEV) can be tested
by the procedure either for BEV application or HEV application, according to the battery system design, based on
the agreement between the cell manufacturer and the customer.
This document specifies the standard test procedures and conditions for basic characteristics
of lithium-ion cells for use in propulsion of battery and hybrid electric vehicles. The tests are
indispensable for obtaining essential data on reliability and abuse behaviour of lithium-ion
cells for use in various designs of battery systems and battery packs.
This document provides standard classification of description of test results to be used for the
design of battery systems or battery packs.
NOTE The reliability and abuse tests for the electrically connected lithium-ion cells may be performed with
reference to this standard.
NOTE The test specification for lithium-ion battery packs and systems is defined in ISO 12405-1 and
ISO 12405-2 (under consideration).
NOTE 2 Cell blocks can be used as an alternative to cells according to the agreement between the cell
manufacturer and the customer.
NOTE 3 The safety requirements of lithium-ion cells for electric vehicle application are defined in IEC 62660-3 [3].
2 Normative references
The following documents are referred to in the text in such a way that some or all of their
content constitutes requirements of this document. For dated references, only the edition
cited applies. For undated references, the latest edition of the referenced document (including
any amendments) applies.
IEC 60050-482, International Electrotechnical Vocabulary – Part 482: Primary and secondary
cells and batteries
IEC 60068-2-64, Environmental testing – Part 2-64: Tests – Test Fh: Vibration, broadband
random and guidance
IEC 61434, Secondary cells and batteries containing alkaline or other non-acid electrolytes –
Guide to the designation of current in alkaline secondary cell and battery standards
ISO 16750-3, Road vehicles – Environmental conditions and testing for electrical and
electronic equipment – Part 3: Mechanical loads
ISO 16750-4, Road vehicles – Environmental conditions and testing for electrical and
electronic equipment – Part 4: Climatic loads
– 8 – IEC 62660-2:2018 RLV © IEC 2018
ISO/TR 8713, Electrically propelled road vehicles – Vocabulary
3 Terms and definitions
For the purposes of this document, the terms and definitions given in IEC 60050-482
ISO/TR 8713 and the following apply.
ISO and IEC maintain terminological databases for use in standardization at the following
addresses:
• IEC Electropedia: available at http://www.electropedia.org/
• ISO Online browsing platform: available at http://www.iso.org/obp
3.1
battery electric vehicle
BEV
electric vehicle with only a traction battery as power source for vehicle propulsion
3.2
cell block
group of cells connected together in parallel configuration with or without protective devices,
e.g. fuse or positive temperature coefficient resistor (PTC), not yet fitted with its final housing,
terminal arrangement and electronic control device
3.3
hybrid electric vehicle
HEV
vehicle with both a rechargeable energy storage system and a fuelled power source for
propulsion
3.4
rated capacity
C
n
quantity of electricity C Ah (ampere-hours) for BEV and C Ah for HEV declared by the
3 1
manufacturer
capacity value of a cell in ampere hours (Ah) determined under specified conditions and
declared by the cell manufacturer
Note 1 to entry: n in C is the time base in hours (h). In this document, n = 3 for BEV application and n = 1 for
n
HEV application unless otherwise specified.
3.5
reference test current
I
t
current in amperes which is expressed as
I (A) = C (Ah)/ 1 (h)
t n
where
C is the rated capacity of the cell ;
n
n is the time base (hours).
reference test current in amperes (A) which is expressed as
I = C / 1
t n
Note 1 to entry: 1 has a dimension of time in hours (h).
Note 2 to entry: See IEC 61434:1996 [4], Clause 2.
3.6
room temperature
temperature of 25 °C ± 2 K
3.7
secondary lithium-ion cell
cell
secondary single cell whose electrical energy is derived from the insertion and extraction
reactions of lithium ions between the anode and the cathode
Note 1 to entry: The secondary lithium-ion cell is a basic manufactured unit providing a source of electrical
energy by direct conversion of chemical energy. The cell consists of electrodes, separators, electrolyte, container
and terminals, and is designed to be charged electrically.
NOTE 2 In this standard, cell or secondary cells means the secondary lithium ion cell to be used for the
propulsion of electric road vehicles.
3.8
state of charge
SOC
available capacity in a battery cell expressed as a percentage of rated capacity
4 Test conditions
4.1 General
The details of the instrumentation used shall be provided in any report of results.
NOTE Test and measurement can be conducted under fixing conditions recommended by the cell manufacturer.
4.2 Measuring instruments
4.2.1 Range of measuring devices
The instruments used shall enable the values of voltage and current to be measured. The
range of these instruments and measuring methods shall be chosen so as to ensure the
accuracy specified for each test.
For analogue instruments, this implies that the readings shall be taken in the last third of the
graduated scale.
Any other measuring instruments may be used provided they give an equivalent accuracy.
4.2.2 Voltage measurement
The resistance of the voltmeters used shall be at least 1 MΩ/V.
4.2.3 Current measurement
The entire assembly of ammeter, shunt and leads shall be of an accuracy class of 0,5 or
better.
4.2.4 Temperature measurements
The cell temperature shall be measured by use of a surface temperature measuring device
capable of an equivalent scale definition and accuracy of calibration as specified in 4.2.1. The
temperature should be measured at a location which most closely reflects the cell or cell block
temperature. The temperature may be measured at additional appropriate locations, if
necessary.
– 10 – IEC 62660-2:2018 RLV © IEC 2018
The examples for temperature measurement are shown in Figure 1. The instructions for
temperature measurement specified by the cell manufacturer shall be followed.
Prismatic or flat cell Cylindrical cell
Temperature measuring device
Cell
Cell Cell
Insulating material
IEC
Figure 1 – Example of temperature measurement of cell
4.2.5 Other measurements
Other values including capacity and power may be measured by use of a measuring device,
provided that it complies with 4.3.
4.3 Tolerance
The overall accuracy of controlled or measured values, relative to the specified or actual
values, shall be within the following tolerances:
a) ± 0,1 % for voltage;
b) ± 1 % for current;
c) ± 2 K for temperature;
d) ± 0,1 % for time;
e) ± 0,1 % for mass;
f) ± 0,1 % for dimensions.
These tolerances comprise the combined accuracy of the measuring instruments, the
measurement technique used, and all other sources of error in the test procedure.
4.4 Test temperature
If not otherwise defined, before each test the cell shall be stabilized at the test temperature
for a minimum of 12 h. This period can be reduced if thermal stabilization is reached. Thermal
stabilization is considered to be reached if after one interval of 1 h, the change of cell
temperature is lower than 1 K.
Unless otherwise stated in this standard, cells shall be tested at room temperature using the
method declared by the manufacturer.
4.4 Thermal stabilization
For the stablization of cell temperature, the cell shall be soaked to a specified ambient
temperature for a minimum of 12 h. This period may be reduced if thermal stabilization is
reached. Thermal stabilization is considered to be reached if after one interval of 1 h, the
change of cell temperature is lower than 1 K.
5 Electrical measurement
5.1 General charge conditions
Unless otherwise stated in this document, prior to electrical measurement test, the cell shall
be charged as follows.
Prior to charging, the cell shall be discharged at room temperature at a constant current
described in Table 1 down to an end-of-discharge voltage specified by the cell manufacturer.
Then, the cell shall be charged according to the charging method declared by the cell
manufacturer at room temperature.
5.2 Capacity
The capacity of a cell shall be measured in accordance with the following phases.
Phase 1 – The cell shall be charged in accordance with 5.1.
After recharge, the cell temperature shall be stabilized in accordance with 4.4.
Phase 2 – The cell shall be discharged at specified temperature at a constant current I (A) to
t
the end-of-discharge voltage that is provided by the cell manufacturer. The discharge current
and temperatures indicated in Table 1 shall be used.
NOTE In addition to Table 1, specific test conditions may be selected based on the agreement
between the cell manufacturer and the customer. Selective test conditions are provided in
Annex A.
The method of designation of test current I is defined in IEC 61434.
t
Table 1 – Discharge conditions
Discharge current
Cell temperature
A
°C
BEV application HEV application
25 1/3 I 1 I
t t
Phase 3 – Measure the discharge endurance duration until the specified end-of-discharge
voltage is reached. Calculate the capacity of cell expressed in Ah up to three significant
figures, by multiplying the discharge current (A) with the discharge duration (h).
5.3 SOC adjustment
The test cells shall be charged as specified below. The SOC adjustment is the procedure to
be followed for preparing cells to the various SOCs for the tests in this document.
– 12 – IEC 62660-2:2018 RLV © IEC 2018
Phase 1 – The cell shall be charged in accordance with 5.1.
Phase 2 – The cell shall be left at rest at room temperature in accordance with 4.4.
Phase 3 – The cell shall be discharged at a constant current according to Table 1 for
(100 − n)/100 × 3 h for BEV application and (100 − n)/100 × 1 h for HEV application, where n
is SOC (%) to be adjusted for each test.
6 Reliability and abuse tests
6.1 General
For all the tests specified in Clause 6, the test installation shall be reported including fixing
and wiring of the cell. If necessary, to prevent deformation, the cell may be maintained during
the test in a manner that does not violate the test purpose.
Before each test, the cell shall be stabilized at room temperature according to 4.4, unless
otherwise specified.
The value of SOC may be changed according to the agreement between the customer and the
cell manufacturer.
6.2 Mechanical test
6.2.1 Vibration
6.2.1.1 Purpose
This test is performed to characterize cell responses to vibration assumed in the use of a
vehicle.
6.2.1.2 Test
The test shall be performed as follows.
a) Adjust the SOC of the cell to 100 % for BEV application, and to 80 % for HEV application
in accordance with 5.3.
b) Perform the test referring to IEC 60068-2-64 random vibration. Use test duration of 8 h for
each plane of the test cell.
c) The RMS acceleration value shall be 27,8 m/s . The power spectrum density (PSD) vs
plotted against frequency is shown in Figure 2 and Table 2. The maximum frequency shall
be 2 000 Hz.
0,1
0,01
1 10 100 1 000 10 000
Frequency (Hz)
IEC
Figure 2 – PSD of acceleration vs. plotted against frequency
Table 2 – Values for PSD and frequency
Frequency PSD
2 2
Hz (m/s ) /Hz
10 20
55 6,5
180 0,25
300 0,25
360 0,14
1 000 0,14
2 000 0,14
6.2.1.3 Test results
The following shall be measured and recorded as test results:
• cell voltage and capacity at the beginning and at the end of before and after the test;
• condition of the cell at the end of the test in accordance with the description specified in
Clause 7.
6.2.2 Mechanical shock
6.2.2.1 Purpose
This test is performed to characterize cell responses to mechanical shocks assumed in the
use of a vehicle.
2 2
PSD ((m/s ) /Hz)
– 14 – IEC 62660-2:2018 RLV © IEC 2018
6.2.2.2 Test
The test shall be performed as follows.
a) Adjust the SOC of the cell to 100 % for BEV application and to 80 % for HEV application
in accordance with 5.3.
b) Perform the test in accordance with ISO 16750-3 as shown in Table 3. Acceleration from
the shock in the test shall be applied in the same direction as the acceleration of the
shock that occurs in the vehicle. If the direction of the effect is not known, the cell shall be
tested in all six spatial directions.
Table 3 – Mechanical shock test – parameters
Pulse shape half-sinusoidal
Acceleration 500 m/s
Duration 6 ms
Number of shocks 10 per test direction
NOTE If more severe test parameters are requested by any regulation, such test conditions may be applied.
6.2.2.3 Test results
The following shall be measured and recorded as test results:
• cell voltage and capacity at the beginning and at the end of before and after the test;
• condition of the cell at the end of the test in accordance with the description specified in
Clause 7.
6.2.3 Crush
6.2.3.1 Purpose
This test is performed to characterize cell responses to external load forces that may can
cause deformation.
6.2.3.2 Test
The test shall be performed as follows.
a) Adjust the SOC of the cell to 100 % for BEV application and 80 % for HEV application in
accordance with 5.3.
b) The cell shall be placed on an insulated flat surface and be crushed with a crushing tool
consisting of a round or semicircular bar, or sphere or hemisphere with a 150 mm
diameter. It is recommended to use the round bar to crush a cylindrical cell, and the
sphere for a prismatic cell (see Figure 3). The force for the crushing shall be applied in a
direction nearly perpendicular to a larger side of a layered face of positive and negative
electrodes inside the cell. The crushing tool shall be selected so that the cell is deformed
nearly in proportion to the increase of crushing force.
c) The force shall be released when an abrupt voltage drop of one-third of the original cell
voltage occurs, or a deformation of 15 % or more of the initial cell dimension occurs, or the
force of 1 000 times the weight of the cell is applied. The cells remain on test for 24 h or
until the case temperature declines by 20 % of the maximum temperature rise, whichever
is the sooner.
Example A Example B
Crushing tool:
Crushing tool:
Hemisphere
Semicircular bar
Cylindrical cell Prismatic cell
: Crushing direction
IEC
Figure 3 – Examples of crush test
6.2.3.3 Test results
The following shall be measured and recorded as test results:
• form of crushing tool;
• crushing speed;
• cell voltage during the test;
• cell temperature during the test;
• condition of the cell at the end of the test in accordance with the description specified in
Clause 7.
6.3 Thermal test
6.3.1 High temperature endurance
6.3.1.1 Purpose
This test is performed to characterize cell responses to high-temperature environment.
6.3.1.2 Test
The test shall be performed as follows.
a) Adjust the SOC of the cell to 100 % for BEV application, and to 80 % for HEV application
in accordance with 5.3.
b) The cell, stabilized at room temperature, shall be placed in a gravity or circulating air-
convection oven. The oven temperature shall be raised at a rate of 5 K/min to a
temperature of 130 °C ± 2 K. The cell shall remain at this temperature for 30 min before
the test is discontinued.
NOTE If necessary, to prevent deformation, the cell may be maintained during the test in a
manner that does not violate the test purpose. The manner to prevent deformation should
be representative of cells inside battery systems and battery packs.
6.3.1.3 Test results
The following shall be measured and recorded as test results:
– 16 – IEC 62660-2:2018 RLV © IEC 2018
• condition of the cell at the end of the test in accordance with the description specified in
Clause 7.
It is recommended to measure the cell temperature and voltage, and oven temperature during
the test.
6.3.2 Temperature cycling
6.3.2.1 Purpose
This test is performed to characterize thermal durability of a cell by exposing at low and high
temperature environment alternately to cause expansion and contraction of cell components.
6.3.2.2 Test
Either of the test procedures specified in 6.2.2.1.1 or 6.2.2.1.2 shall be performed according
to the agreement between the customer and the manufacturer.
6.2.2.1.1 Test without electrical operation
The test shall be performed as follows.
a) Adjust the SOC of the cell to 100 % for BEV application, and to 80 % for HEV application
in accordance with 5.3.
b) Perform the temperature cycling in accordance with ISO 16750-4 as shown in Table 4.
The minimum operating temperature shall be −40 °C or T specified by the cell
min
manufacturer and the maximum operating temperature shall be 85 °C or T specified by
max
the cell manufacturer. Perform 30 test cycles as specified.
Table 4 – Temperatures and time duration for temperature cycling
Cumulative time Temperature
min °C
0 25 20
60 T
min
150 T
min
210 25 20
300 T
max
410 T
max
480 25 20
6.2.2.1.2 Test with electrical operation
The test shall be performed as follows.
a) Adjust the SOC of cell to 80 % for BEV application, and to 60 % for HEV application in
accordance with 5.3.
b) Perform the temperature cycling in accordance with ISO 16750-4 as shown in Table 5.
The minimum operating temperature shall be –20 °C and the maximum operating
temperature shall be 65 °C.
c) Perform the following current profiles during each temperature cycle:
– BEV current profile in accordance with Figure 4 and Table 6;
– HEV current profile in accordance with Figure 6 and Table 7.
d) Perform 30 test cycles as specified.
Table 5 – Temperatures and time duration for temperature cycling
Cumulative time Temperature
min °C
0 25
60 –20
150 –20
210 25
300 65
410 65
480 25
100 3
2,5
SOC
1,5
Discharge Temperature
0,5
30 C-rate
Charge
–0,5
–1
0 30
60 90 120 150 180 210 240 270 300 330 360 390 420 450 480
–10
–1,5
–20
–30 –2
Time (min)
IEC 2879/10
Figure 4 – BEV current profile for temperature cycling
SOC (%), T (°C)
C-rate
– 18 – IEC 62660-2:2018 RLV © IEC 2018
Table 6 – Test steps and BEV current profile
BEV current profile Background information
Step time Cumulative time Delta SOC SOC
Step C-rate Example
min min % %
0 0 0 80
1 145 145 0 0 80
2 1 146 1 –1,67 78,33 1 min driving
3 64 210 0
4 12 222 0,5 –10 68,33 12 min driving
5 1 223 0
6 39 262 –0,2 13 81,33 charging
7 138 400 0
8 3 403 0,5 –2,5 78,83 3 min driving
9 77 480 0 78,83
SOC
BEV: all 30 test cycles
0 30 60 90 120 150 180 210 240
Time (min)
IEC 2880/10
Figure 5 – SOC level over all test cycles – BEV application
Figure 5 shows the SOC level over the cumulative test time for a BEV application.
SOC (%)
SOC (%)
T (°C)
Discharge
10 C-rate
5 000 10 000 20 000 25 000
15 000
–10
Charge
–30
Time (s)
IEC 2881/10
Figure 6 – HEV current profile for temperature cycling
Table 7 – Test steps and HEV current profile
HEV current profile Background information
Step time Cumulative time Delta SOC SOC
Step C-rate Example
s s % %
0 0 0 60
1 8 700 8 700 0 60
2 5 8 705 10 –1,39 58,61 5 s cold start
3 5 695 14 400 0
4 10 14 410 –10 2,78 61,39 10 s recuperation
5 590 15 000 0
6 120 15 120 –5 16,7 78,09 2 min charging
7 480 15 600 0
8 120 15 720 5 –16,7 61,39 2 min driving
9 8 580 24 300 0
10 5 24 305 10 –1,39 60 5 s hot start
11 4 495 28 800 0 60
6.3.2.3 Test results
The following shall be measured and recorded as test results:
• cell voltage and capacity at the beginning and at the end of the test;
• condition of the cell at the end of the test in accordance with the description specified in
Clause 7;
• cell voltage, current and temperature shall be continuously recorded during each cycle.
6.4 Electrical test
NOTE If necessary, to prevent deformation, the cell may be maintained during the test in a manner that does not
violate the test purpose.
6.4.1 External short circuit
6.4.1.1 Purpose
This test is performed to characterize cell responses to external short circuit.
– 20 – IEC 62660-2:2018 RLV © IEC 2018
6.4.1.2 Test
The test shall be performed as follows.
a) Adjust the SOC of the cell to 100 % in accordance with 5.3.
b) The cell adjusted as in a) shall be stored at room temperature, and then be short-circuited
by connecting the positive and negative terminals with an external resistance for 10 min.
The total external resistance shall be equal to or less than 5 mΩ as agreed between the
customer and the cell manufacturer.
6.4.1.3 Test results
The following shall be measured and recorded as test results; the sample rate for voltage and
current recording shall be ≤ 10 ms:
– cell voltage during the test;
– cell current during the test. If the accuracy deviates from the requirements of 4.3, it shall
be reported;
– cell temperature during the test;
– total external resistance value;
– condition of the cell at the end of the test in accordance with the description specified in
Clause 7.
6.4.2 Overcharge
6.4.2.1 Purpose
This test is performed to characterize cell responses to overcharge.
6.4.2.2 Test
The test shall be performed as follows.
a) Adjust the SOC of the cell to 100 % in accordance with 5.3.
b) Continue charging the cell beyond the 100 % SOC with charging current 1 I for BEV
t
application and 5 I for HEV application at room temperature using a power supply
t
sufficient to provide the constant charging current. The overcharge test shall be
discontinued when the voltage of cell reaches twice the maximum voltage specified by the
manufacturer, or the quantity of electricity applied to the cell reaches 200 % SOC
equivalent.
Continue charging the cell beyond the 100 % SOC with a charging current agreed by the
customer and the cell manufacturer at room temperature using a power supply sufficient to
provide the constant charging current. The overcharge test shall be discontinued when the
applied voltage reaches a value agreed between the customer and the supplier, or until
charging is disabled by the cell protective device, if any, or until the cell fails.
6.4.2.3 Test results
The following shall be measured and recorded as test results:
– cell voltage during the test;
– cell current during the test;
– cell temperature during the test;
– condition of the cell at the end of the test in accordance with the description specified in
Clause 7.
6.4.3 Forced discharge
6.4.3.1 Purpose
This test is performed to characterize cell responses to over discharge.
6.4.3.2 Test
Discharge a fully discharged cell at 1I A for 90 min.
t
The test shall be performed as follows.
a) Adjust the SOC of the cell to 0 % in accordance with 5.3.
b) Continue discharging the cell beyond the 0 % SOC at 1 I (A) for 90 min at room
t
temperature.
6.4.3.3 Test results
The following shall be measured and recorded as test results:
– cell voltage during the test;
– cell current during the test;
– cell temperature during the test;
– condition of the cell at the end of the test in accordance with the description specified in
Clause 7.
7 Description of test results
The results of tests specified in this document shall be recorded with the descriptions
in Table 5. Each test result may include multiple descriptions. The test results may be
described with relevant materials such as photos.
Table 5 – Test result description
Description Effect
No effect No effect. No change in appearance.
Deformation Change or deformation in appearance including swelling.
Escape of liquid electrolyte from vent or venting with mist release.
Venting
NOTE For the pouch cell, the intended venting mechanism can be a controlled opening of
the cell casing.
Visible escape of liquid electrolyte from a part except vent, such as casing, sealing part
Leakage
and/or terminals.
Smoking Release of fumes, including possible soot particles, from vent.
Mechanical failure of the container case of the cell induced by an internal or external
Rupture cause, resulting in exposure or spillage but not ejection of materials. Including smoking at
the rupture
Emission of flames from a cell or cell block for more than 1 s.
Fire
NOTE Sparks and arcing are not considered as flames.
Failure that occurs when a cell container opens violently and major components are
Explosion
forcibly expelled.
– 22 – IEC 62660-2:2018 RLV © IEC 2018
Annex A
(informative)
Selective test conditions
Annex A provides additional and selective conditions for the capacity test specified in 5.2. The
test conditions "r" in Table A.1 are specified in this doc
...
IEC 62660-2 ®
Edition 2.0 2018-12
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Secondary lithium-ion cells for the propulsion of electric road vehicles –
Part 2: Reliability and abuse testing
Éléments d’accumulateurs lithium-ion pour la propulsion des véhicules routiers
électriques –
Partie 2: Essais de fiabilité et de traitement abusif
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IEC 62660-2 ®
Edition 2.0 2018-12
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Secondary lithium-ion cells for the propulsion of electric road vehicles –
Part 2: Reliability and abuse testing
Éléments d’accumulateurs lithium-ion pour la propulsion des véhicules routiers
électriques –
Partie 2: Essais de fiabilité et de traitement abusif
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 29.220.20; 43.120 ISBN 978-2-8322-6289-4
– 2 – IEC 62660-2:2018 © IEC 2018
CONTENTS
FOREWORD . 3
INTRODUCTION . 5
1 Scope . 6
2 Normative references . 6
3 Terms and definitions . 6
4 Test conditions . 8
4.1 General . 8
4.2 Measuring instruments . 8
4.2.1 Range of measuring devices . 8
4.2.2 Voltage measurement . 8
4.2.3 Current measurement . 8
4.2.4 Temperature measurements . 8
4.2.5 Other measurements . 9
4.3 Tolerance . 9
4.4 Thermal stabilization . 9
5 Electrical measurement . 9
5.1 General charge conditions . 9
5.2 Capacity . 10
5.3 SOC adjustment . 10
6 Reliability and abuse tests . 10
6.1 General . 10
6.2 Mechanical test . 11
6.2.1 Vibration . 11
6.2.2 Mechanical shock . 12
6.2.3 Crush . 13
6.3 Thermal test . 14
6.3.1 High temperature endurance. 14
6.3.2 Temperature cycling . 14
6.4 Electrical test . 15
6.4.1 External short circuit . 15
6.4.2 Overcharge . 16
6.4.3 Forced discharge . 16
7 Description of test results . 16
Annex A (informative) Selective test conditions . 18
Bibliography . 19
Figure 1 – Example of temperature measurement of cell . 9
Figure 2 – PSD of acceleration plotted against frequency . 11
Figure 3 – Examples of crush test . 13
Table 1 – Discharge conditions . 10
Table 2 – Values for PSD and frequency . 12
Table 3 – Mechanical shock test – parameters . 12
Table 4 – Temperatures and time duration for temperature cycling . 15
Table 5 – Test result description . 17
Table A.1 – Capacity test conditions . 18
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
SECONDARY LITHIUM-ION CELLS FOR
THE PROPULSION OF ELECTRIC ROAD VEHICLES –
Part 2: Reliability and abuse testing
FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote
international co-operation on all questions concerning standardization in the electrical and electronic fields. To
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6) All users should ensure that they have the latest edition of this publication.
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8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of
patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 62660-2 has been prepared by IEC technical committee 21:
Secondary cells and batteries.
This second edition cancels and replaces the first edition published in 2010. This edition
constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) The procedure of forced discharge test has been clarified (6.4.3.2).
b) "Cell block" has been added to the scope (Clause 1).
c) Option of temperature cycling test with electrical operation has been deleted (6.3.2).
d) The test conditions for overcharge test have been revised (6.4.2.2).
– 4 – IEC 62660-2:2018 © IEC 2018
The text of this International Standard is based on the following documents:
FDIS Report on voting
21/976/FDIS 21/986/RVD
Full information on the voting for the approval of this International Standard can be found in
the report on voting indicated in the above table.
This document has been drafted in accordance with the ISO/IEC Directives, Part 2.
A list of all the parts in the IEC 62660 series, published under the general title Secondary
lithium-ion cells for the propulsion of electric road vehicles, can be found on the IEC website.
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under "http://webstore.iec.ch" in the data related to
the specific document. At this date, the document will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
IMPORTANT – The 'colour inside' logo on the cover page of this publication indicates
that it contains colours which are considered to be useful for the correct
understanding of its contents. Users should therefore print this document using a
colour printer.
INTRODUCTION
The commercialization of electric road vehicles including battery, hybrid and plug-in hybrid
electric vehicles has been accelerated in the global market, responding to the global concerns
on CO reduction and energy security. This, in turn, has led to rapidly increasing demand for
high-power and high-energy-density traction batteries. Lithium-ion batteries are estimated to
be one of the most promising secondary batteries for the propulsion of electric vehicles. In the
light of the rapid spread of hybrid electric vehicles and the emergence of battery and plug-in
hybrid electric vehicles, a standard method for testing reliability and abuse requirements of
lithium-ion batteries is indispensable for securing a basic level of safety and obtaining
essential data for the design of vehicle systems and battery packs.
This document specifies reliability and abuse testing for automobile traction lithium-ion cells
that basically differ from the other cells including those for portable and stationary
applications specified by other IEC standards. For automobile application, it is important to
note the usage specificity; i.e. the design diversity of automobile battery packs and systems,
and specific requirements for cells and batteries corresponding to each of such designs.
Based on these facts, the purpose of this document is to provide a basic test methodology
with general versatility, which serves a function in common primary testing of lithium-ion cells
to be used in a variety of battery systems. This document does not provide any pass-fail
criteria for the tests, but specifies a standard classification of descriptions for test results.
This document is associated with ISO 12405-4 [1] .
IEC 62660-1 [2] specifies the performance testing of lithium-ion cells for electric vehicle
application.
IEC 62660-3 [3] specifies the safety requirements of lithium-ion cells for electric vehicle
application.
___________
Numbers in square brackets refer to the Bibliography.
– 6 – IEC 62660-2:2018 © IEC 2018
SECONDARY LITHIUM-ION CELLS FOR
THE PROPULSION OF ELECTRIC ROAD VEHICLES –
Part 2: Reliability and abuse testing
1 Scope
This part of IEC 62660 specifies test procedures to observe the reliability and abuse
behaviour of secondary lithium-ion cells and cell blocks used for propulsion of electric
vehicles including battery electric vehicles (BEV) and hybrid electric vehicles (HEV).
NOTE 1 Secondary lithium-ion cells used for propulsion of plug-in hybrid electric vehicles (PHEV) can be tested
by the procedure either for BEV application or HEV application, according to the battery system design, based on
the agreement between the cell manufacturer and the customer.
This document specifies the standard test procedures and conditions for basic characteristics
of lithium-ion cells for use in propulsion of battery and hybrid electric vehicles. The tests are
indispensable for obtaining essential data on reliability and abuse behaviour of lithium-ion
cells for use in various designs of battery systems and battery packs.
This document provides standard classification of description of test results to be used for the
design of battery systems or battery packs.
NOTE 2 Cell blocks can be used as an alternative to cells according to the agreement between the cell
manufacturer and the customer.
NOTE 3 The safety requirements of lithium-ion cells for electric vehicle application are defined in IEC 62660-3 [3].
2 Normative references
The following documents are referred to in the text in such a way that some or all of their
content constitutes requirements of this document. For dated references, only the edition
cited applies. For undated references, the latest edition of the referenced document (including
any amendments) applies.
IEC 60068-2-64, Environmental testing – Part 2-64: Tests – Test Fh: Vibration, broadband
random and guidance
ISO 16750-3, Road vehicles – Environmental conditions and testing for electrical and
electronic equipment – Part 3: Mechanical loads
Road vehicles – Environmental conditions and testing for electrical and
ISO 16750-4,
electronic equipment – Part 4: Climatic loads
ISO/TR 8713, Electrically propelled road vehicles – Vocabulary
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO/TR 8713 and the
following apply.
ISO and IEC maintain terminological databases for use in standardization at the following
addresses:
• IEC Electropedia: available at http://www.electropedia.org/
• ISO Online browsing platform: available at http://www.iso.org/obp
3.1
battery electric vehicle
BEV
electric vehicle with only a traction battery as power source for vehicle propulsion
3.2
cell block
group of cells connected together in parallel configuration with or without protective devices,
e.g. fuse or positive temperature coefficient resistor (PTC), not yet fitted with its final housing,
terminal arrangement and electronic control device
3.3
hybrid electric vehicle
HEV
vehicle with both a rechargeable energy storage system and a fuelled power source for
propulsion
3.4
rated capacity
C
n
capacity value of a cell in ampere hours (Ah) determined under specified conditions and
declared by the cell manufacturer
Note 1 to entry: n in C is the time base in hours (h). In this document, n = 3 for BEV application and n = 1 for
n
HEV application unless otherwise specified.
3.5
I
t
reference test current in amperes (A) which is expressed as
I = C / 1
t n
Note 1 to entry: 1 has a dimension of time in hours (h).
Note 2 to entry: See IEC 61434:1996 [4], Clause 2.
3.6
room temperature
temperature of 25 °C ± 2 K
3.7
secondary lithium-ion cell
cell
secondary single cell whose electric energy is derived from the insertion and extraction
reactions of lithium ions between the anode and the cathode
Note 1 to entry: The secondary lithium-ion cell is a basic manufactured unit providing a source of electric energy
by direct conversion of chemical energy. The cell consists of electrodes, separators, electrolyte, container and
terminals, and is designed to be charged electrically.
3.8
state of charge
SOC
capacity in a cell expressed as a percentage of rated capacity
– 8 – IEC 62660-2:2018 © IEC 2018
4 Test conditions
4.1 General
The details of the instrumentation used shall be provided in any report of results.
NOTE Test and measurement can be conducted under fixing conditions recommended by the cell manufacturer.
4.2 Measuring instruments
4.2.1 Range of measuring devices
The instruments used shall enable the values of voltage and current to be measured. The
range of these instruments and measuring methods shall be chosen so as to ensure the
accuracy specified for each test.
For analogue instruments, this implies that the readings shall be taken in the last third of the
graduated scale.
Any other measuring instruments may be used provided they give an equivalent accuracy.
4.2.2 Voltage measurement
The resistance of the voltmeters used shall be at least 1 MΩ/V.
4.2.3 Current measurement
The entire assembly of ammeter, shunt and leads shall be of an accuracy class of 0,5 or
better.
4.2.4 Temperature measurements
The cell temperature shall be measured by use of a surface temperature measuring device
capable of an equivalent scale definition and accuracy of calibration as specified in 4.2.1. The
temperature should be measured at a location which most closely reflects the cell or cell block
temperature. The temperature may be measured at additional appropriate locations, if
necessary.
The examples for temperature measurement are shown in Figure 1. The instructions for
temperature measurement specified by the cell manufacturer shall be followed.
Prismatic or flat cell Cylindrical cell
Temperature measuring device
Cell
Cell Cell
Insulating material
IEC
Figure 1 – Example of temperature measurement of cell
4.2.5 Other measurements
Other values may be measured by use of a measuring device, provided that it complies with
4.3.
4.3 Tolerance
The overall accuracy of controlled or measured values, relative to the specified or actual
values, shall be within the following tolerances:
a) ± 0,1 % for voltage;
b) ± 1 % for current;
c) ± 2 K for temperature;
d) ± 0,1 % for time;
e) ± 0,1 % for mass;
f) ± 0,1 % for dimensions.
These tolerances comprise the combined accuracy of the measuring instruments, the
measurement technique used, and all other sources of error in the test procedure.
4.4 Thermal stabilization
For the stablization of cell temperature, the cell shall be soaked to a specified ambient
temperature for a minimum of 12 h. This period may be reduced if thermal stabilization is
reached. Thermal stabilization is considered to be reached if after one interval of 1 h, the
change of cell temperature is lower than 1 K.
5 Electrical measurement
5.1 General charge conditions
Unless otherwise stated in this document, prior to electrical measurement test, the cell shall
be charged as follows.
– 10 – IEC 62660-2:2018 © IEC 2018
Prior to charging, the cell shall be discharged at room temperature at a constant current
described in Table 1 down to an end-of-discharge voltage specified by the cell manufacturer.
Then, the cell shall be charged according to the charging method declared by the cell
manufacturer at room temperature.
5.2 Capacity
The capacity of a cell shall be measured in accordance with the following phases.
Phase 1 – The cell shall be charged in accordance with 5.1.
After recharge, the cell temperature shall be stabilized in accordance with 4.4.
Phase 2 – The cell shall be discharged at specified temperature at a constant current I (A) to
t
the end-of-discharge voltage that is provided by the cell manufacturer. The discharge current
and temperatures indicated in Table 1 shall be used.
In addition to Table 1, specific test conditions may be selected based on the agreement
between the cell manufacturer and the customer. Selective test conditions are provided in
Annex A.
Table 1 – Discharge conditions
Discharge current
Cell temperature
A
°C
BEV application HEV application
25 1/3 I 1 I
t t
Phase 3 – Measure the discharge duration until the specified end-of-discharge voltage is
reached. Calculate the capacity of cell expressed in Ah up to three significant figures, by
multiplying the discharge current (A) with the discharge duration (h).
5.3 SOC adjustment
The test cells shall be charged as specified below. The SOC adjustment is the procedure to
be followed for preparing cells to the various SOCs for the tests in this document.
Phase 1 – The cell shall be charged in accordance with 5.1.
Phase 2 – The cell shall be left at rest at room temperature in accordance with 4.4.
Phase 3 – The cell shall be discharged at a constant current according to Table 1 for
(100 − n)/100 × 3 h for BEV application and (100 − n)/100 × 1 h for HEV application, where n
is SOC (%) to be adjusted for each test.
6 Reliability and abuse tests
6.1 General
For all the tests specified in Clause 6, the test installation shall be reported including fixing
and wiring of the cell. If necessary, to prevent deformation, the cell may be maintained during
the test in a manner that does not violate the test purpose.
Before each test, the cell shall be stabilized at room temperature according to 4.4, unless
otherwise specified.
The value of SOC may be changed according to the agreement between the customer and the
cell manufacturer.
6.2 Mechanical test
6.2.1 Vibration
6.2.1.1 Purpose
This test is performed to characterize cell responses to vibration assumed in the use of a
vehicle.
6.2.1.2 Test
The test shall be performed as follows.
a) Adjust the SOC of the cell to 100 % for BEV application, and to 80 % for HEV application
in accordance with 5.3.
b) Perform the test referring to IEC 60068-2-64 random vibration. Use test duration of 8 h for
each plane of the test cell.
. The power spectrum density (PSD)
c) The RMS acceleration value shall be 27,8 m/s
plotted against frequency is shown in Figure 2 and Table 2. The maximum frequency shall
be 2 000 Hz.
0,1
0,01
1 10 100 1 000 10 000
Frequency (Hz)
IEC
Figure 2 – PSD of acceleration plotted against frequency
2 2
PSD ((m/s ) /Hz)
– 12 – IEC 62660-2:2018 © IEC 2018
Table 2 – Values for PSD and frequency
Frequency PSD
2 2
Hz (m/s ) /Hz
10 20
55 6,5
180 0,25
300 0,25
360 0,14
1 000 0,14
2 000 0,14
6.2.1.3 Test results
The following shall be measured and recorded as test results:
• cell voltage and capacity before and after the test;
• condition of the cell at the end of the test in accordance with the description specified in
Clause 7.
6.2.2 Mechanical shock
6.2.2.1 Purpose
This test is performed to characterize cell responses to mechanical shocks assumed in the
use of a vehicle.
6.2.2.2 Test
The test shall be performed as follows.
a) Adjust the SOC of the cell to 100 % for BEV application and to 80 % for HEV application
in accordance with 5.3.
b) Perform the test in accordance with ISO 16750-3 as shown in Table 3. Acceleration from
the shock in the test shall be applied in the same direction as the acceleration of the
shock that occurs in the vehicle. If the direction of the effect is not known, the cell shall be
tested in all six spatial directions.
Table 3 – Mechanical shock test – parameters
Pulse shape half-sinusoidal
Acceleration 500 m/s
Duration 6 ms
Number of shocks 10 per test direction
6.2.2.3 Test results
The following shall be measured and recorded as test results:
• cell voltage and capacity before and after the test;
• condition of the cell at the end of the test in accordance with the description specified in
Clause 7.
6.2.3 Crush
6.2.3.1 Purpose
This test is performed to characterize cell responses to external load forces that can cause
deformation.
6.2.3.2 Test
The test shall be performed as follows.
a) Adjust the SOC of the cell to 100 % for BEV application and 80 % for HEV application in
accordance with 5.3.
b) The cell shall be placed on an insulated flat surface and be crushed with a crushing tool
consisting of a round or semicircular bar, or sphere or hemisphere with a 150 mm
diameter. It is recommended to use the round bar to crush a cylindrical cell, and the
sphere for a prismatic cell (see Figure 3). The force for the crushing shall be applied in a
direction nearly perpendicular to a larger side of a layered face of positive and negative
electrodes inside the cell. The crushing tool shall be selected so that the cell is deformed
nearly in proportion to the increase of crushing force.
c) The force shall be released when an abrupt voltage drop of one-third of the original cell
voltage occurs, or a deformation of 15 % or more of the initial cell dimension occurs, or the
force of 1 000 times the weight of the cell is applied. The cells remain on test for 24 h or
until the case temperature declines by 20 % of the maximum temperature rise, whichever
is the sooner.
Example A Example B
Crushing tool:
Crushing tool:
Hemisphere
Semicircular bar
Cylindrical cell Prismatic cell
: Crushing direction
IEC
Figure 3 – Examples of crush test
6.2.3.3 Test results
The following shall be measured and recorded as test results:
• form of crushing tool;
• crushing speed;
• cell voltage during the test;
• cell temperature during the test;
• condition of the cell at the end of the test in accordance with the description specified in
Clause 7.
– 14 – IEC 62660-2:2018 © IEC 2018
6.3 Thermal test
6.3.1 High temperature endurance
6.3.1.1 Purpose
This test is performed to characterize cell responses to high-temperature environment.
6.3.1.2 Test
The test shall be performed as follows.
a) Adjust the SOC of the cell to 100 % for BEV application, and to 80 % for HEV application
in accordance with 5.3.
b) The cell, stabilized at room temperature, shall be placed in a gravity or circulating air-
convection oven. The oven temperature shall be raised at a rate of 5 K/min to a
temperature of 130 °C. The cell shall remain at this temperature for 30 min before the test
is discontinued. If necessary, to prevent deformation, the cell may be maintained during
the test in a manner that does not violate the test purpose. The manner to prevent
deformation should be representative of cells inside battery systems and battery packs.
6.3.1.3 Test results
The following shall be recorded as test results:
• condition of the cell at the end of the test in accordance with the description specified in
Clause 7.
It is recommended to measure the cell temperature and voltage, and oven temperature during
the test.
6.3.2 Temperature cycling
6.3.2.1 Purpose
This test is performed to characterize thermal durability of a cell by exposing at low and high
temperature environment alternately to cause expansion and contraction of cell components.
6.3.2.2 Test
The test shall be performed as follows.
a) Adjust the SOC of the cell to 100 % for BEV application, and to 80 % for HEV application
in accordance with 5.3.
b) Perform the temperature cycling in accordance with ISO 16750-4 as shown in Table 4.
The minimum operating temperature shall be −40 °C or T specified by the cell
min
manufacturer and the maximum operating temperature shall be 85 °C or T specified by
max
the cell manufacturer. Perform 30 test cycles as specified.
Table 4 – Temperatures and time duration for temperature cycling
Cumulative time Temperature
min °C
0 20
60 T
min
150 T
min
210 20
300 T
max
410 T
max
480 20
6.3.2.3 Test results
The following shall be measured and recorded as test results:
• cell voltage and capacity at the beginning and at the end of the test;
• condition of the cell at the end of the test in accordance with the description specified in
Clause 7;
• cell voltage and temperature shall be continuously recorded during each cycle.
6.4 Electrical test
6.4.1 External short circuit
6.4.1.1 Purpose
This test is performed to characterize cell responses to external short circuit.
6.4.1.2 Test
The test shall be performed as follows.
a) Adjust the SOC of the cell to 100 % in accordance with 5.3.
b) The cell adjusted as in a) shall be stored at room temperature, and then be short-circuited
by connecting the positive and negative terminals with an external resistance for 10 min.
The total external resistance shall be equal to or less than 5 mΩ as agreed between the
customer and the cell manufacturer.
6.4.1.3 Test results
The following shall be measured and recorded as test results; the sample rate for voltage and
current recording shall be ≤ 10 ms:
– cell voltage during the test;
– cell current during the test. If the accuracy deviates from the requirements of 4.3, it shall
be reported;
– cell temperature during the test;
– total external resistance value;
– condition of the cell at the end of the test in accordance with the description specified in
Clause 7.
– 16 – IEC 62660-2:2018 © IEC 2018
6.4.2 Overcharge
6.4.2.1 Purpose
This test is performed to characterize cell responses to overcharge.
6.4.2.2 Test
The test shall be performed as follows.
a) Adjust the SOC of the cell to 100 % in accordance with 5.3.
b) Continue charging the cell beyond the 100 % SOC with a charging current agreed by the
customer and the cell manufacturer at room temperature using a power supply sufficient to
provide the constant charging current. The overcharge test shall be discontinued when the
applied voltage reaches a value agreed between the customer and the supplier, or until
charging is disabled by the cell protective device, if any, or until the cell fails.
6.4.2.3 Test results
The following shall be measured and recorded as test results:
– cell voltage during the test;
– cell current during the test;
– cell temperature during the test;
– condition of the cell at the end of the test in accordance with the description specified in
Clause 7.
6.4.3 Forced discharge
6.4.3.1 Purpose
This test is performed to characterize cell responses to over discharge.
6.4.3.2 Test
The test shall be performed as follows.
a) Adjust the SOC of the cell to 0 % in accordance with 5.3.
b) Continue discharging the cell beyond the 0 % SOC at 1 I (A) for 90 min at room
t
temperature.
6.4.3.3 Test results
The following shall be measured and recorded as test results:
– cell voltage during the test;
– cell current during the test;
– cell temperature during the test;
– condition of the cell at the end of the test in accordance with the description specified in
Clause 7.
7 Description of test results
The results of tests specified in this document shall be recorded with the descriptions
in Table 5. Each test result may include multiple descriptions. The test results may be
described with relevant materials such as photos.
Table 5 – Test result description
Description Effect
No effect No effect. No change in appearance.
Deformation Change or deformation in appearance including swelling.
Escape of liquid electrolyte from vent or venting with mist release.
Venting
NOTE For the pouch cell, the intended venting mechanism can be a controlled opening of
the cell casing.
Visible escape of liquid electrolyte from a part except vent, such as casing, sealing part
Leakage
and/or terminals.
Smoking Release of fumes, including possible soot particles, from vent.
Mechanical failure of the container case of the cell induced by an internal or external
Rupture
cause, resulting in exposure or spillage but not ejection of materials.
Emission of flames from a cell or cell block for more than 1 s.
Fire
NOTE Sparks and arcing are not considered as flames.
Failure that occurs when a cell container opens violently and major components are
Explosion
forcibly expelled.
– 18 – IEC 62660-2:2018 © IEC 2018
Annex A
(informative)
Selective test conditions
Annex A provides additional and selective conditions for the capacity test specified in 5.2. The
test conditions "r" in Table A.1 are specified in this document. In addition, the test conditions
"a" may be selected based on the agreement between the cell manufacturer and the customer.
Table A.1 – Capacity test conditions
Cell temperature
Discharge
Application
current
−20 °C 0 °C 25 °C 45 °C
0,2 I a a a a
t
1/3 I a r r r
t
BEV
1 I a a a a
t
5 I a a a a
t
0,2 I a a a a
t
1/3 I a a a a
t
HEV 1 I a r r r
t
10 I a a a a
t
I a a a a
dmax
Bibliography
[1] ISO 12405-4, Electrically propelled road vehicles – Test specification for lithium-ion
traction battery packs and systems – Part 4: Performance testing
[2] IEC 62660-1, Secondary lithium-ion cells for the propulsion of electric road vehicles –
Part 1: Performance testing
[3] IEC 62660-3, Secondary lithium-ion cells for the propulsion of electric road vehicles –
Part 3: Safety requirements
[4] IEC 61434:1996, Secondary cells and batteries containing alkaline or other non-acid
electrolytes – Guide to the designation of current in alkaline secondary cell and battery
standards
___________
– 20 – IEC 62660-2:2018 © IEC 2018
SOMMAIRE
AVANT-PROPOS . 21
INTRODUCTION . 23
1 Domaine d’application . 24
2 Références normatives . 24
3 Termes et définitions . 24
4 Conditions d'essai . 26
4.1 Généralités . 26
4.2 Instruments de mesure . 26
4.2.1 Amplitude des dispositifs de mesure . 26
4.2.2 Mesure de la tension . 26
4.2.3 Mesure du courant . 26
4.2.4 Mesure de la température . 26
4.2.5 Autres mesures . 27
4.3 Tolérance . 27
4.4 Stabilisation thermique. 27
5 Mesures électriques . 27
5.1 Conditions générales de charge . 27
5.2 Capacité . 28
5.3 Ajustement de l'état de charge (SOC) . 28
6 Essais de fiabilité et de traitement abusif . 28
6.1 Généralités . 28
6.2 Essais mécaniques . 29
6.2.1 Vibrations .
...
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