IEC 62660-3:2022

Secondary lithium-ion cells for the propulsion of electric road vehicles - Part 3: Safety requirements

IEC 62660-3:2022 is available as IEC 62660-3:2022 RLV which contains the International Standard and its Redline version, showing all changes of the technical content compared to the previous edition.IEC 62660-3:2022 specifies test procedures and acceptance criteria for safety performance of secondary lithium-ion cells and cell blocks used for propulsion of electric vehicles (EV) including battery electric vehicles (BEV) and hybrid electric vehicles (HEV). This document determines the basic safety performance of cells used in a battery pack and system under intended use and reasonably foreseeable misuse or incident, during the normal operation of the EV. The safety requirements of the cell in this document are based on the premise that the cells are properly used in a battery pack and system within the limits for voltage, current and temperature as specified by the cell manufacturer (cell operating region).

Eléments d'accumulateurs lithium-ion pour la propulsion des véhicules routiers électriques - Partie 3: Exigences de sécurité

IEC 62660-3:2022 est disponible sous forme de IEC 62660-3:2022 RLV qui contient la Norme internationale et sa version Redline, illustrant les modifications du contenu technique depuis l'édition précédente.L'IEC 62660-3:2022 spécifie les procédures d'essai et les critères d'acceptation en matière de performance de sécurité des éléments d'accumulateurs lithium-ion et des blocs d'éléments utilisés pour la propulsion des véhicules électriques (VE), y compris les véhicules électriques à batterie (VEB) et les véhicules électriques hybrides (VEH). Le présent document a pour objet de déterminer les performances de sécurité de base des éléments utilisés dans un groupe et système de batteries dans les conditions d'utilisation prévue et les mauvaises utilisations ou incidents raisonnablement prévisibles, pendant le fonctionnement normal du VE. Dans le présent document, les exigences de sécurité de l'élément s'appuient sur l'hypothèse selon laquelle les éléments sont correctement utilisés dans un groupe et système de batteries dans les limites de tension, de courant et de température spécifiées par le fabricant de l'élément (plage de fonctionnement de l'élément).

General Information

• Status: Published
• Publication Date: 28-Feb-2022
• ICS: 29.220.20 - Acid secondary cells and batteries
• ICS: 43.120 - Electric road vehicles
• Technical Committee: TC 21 - Secondary cells and batteries
• Current Stage: PPUB - Publication issued
• Completion Date: 01-Mar-2022

Standards Content (sample)

IEC 62660-3
Edition 2.0 2022-03
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Secondary lithium-ion cells for the propulsion of electric road vehicles –
Part 3: Safety requirements
Éléments d’accumulateurs lithium-ion pour la propulsion des véhicules routiers
électriques –
Partie 3: Exigences de sécurité
IEC 62660-3:2022-03(en-fr)
---------------------- Page: 1 ----------------------
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---------------------- Page: 2 ----------------------
IEC 62660-3
Edition 2.0 2022-03
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Secondary lithium-ion cells for the propulsion of electric road vehicles –
Part 3: Safety requirements
Éléments d’accumulateurs lithium-ion pour la propulsion des véhicules routiers
électriques –
Partie 3: Exigences de sécurité
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 29.220.20; 43.120 ISBN 978-2-8322-1083-3

Warning! Make sure that you obtained this publication from an authorized distributor.

Attention! Veuillez vous assurer que vous avez obtenu cette publication via un distributeur agréé.

® Registered trademark of the International Electrotechnical Commission
Marque déposée de la Commission Electrotechnique Internationale
---------------------- Page: 3 ----------------------
– 2 – IEC 62660-3:2022 © IEC 2022
CONTENTS

FOREWORD ........................................................................................................................... 4

1 Scope .............................................................................................................................. 6

2 Normative references ...................................................................................................... 6

3 Terms and definitions ...................................................................................................... 6

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

4.4 Thermal stabilization ............................................................................................. 10

5 Electrical measurement ................................................................................................. 10

5.1 General charge conditions .................................................................................... 10

5.2 Capacity ............................................................................................................... 11

5.3 SOC adjustment .................................................................................................... 11

6 Safety tests ................................................................................................................... 11

6.1 General ................................................................................................................. 11

6.2 Mechanical tests ................................................................................................... 12

6.2.1 Mechanical shock .......................................................................................... 12

6.2.2 Crush ............................................................................................................ 12

6.3 Thermal test .......................................................................................................... 13

6.3.1 High temperature endurance.......................................................................... 13

6.3.2 Temperature cycling ...................................................................................... 13

6.4 Electrical tests ...................................................................................................... 14

6.4.1 External short-circuit ...................................................................................... 14

6.4.2 Overcharge .................................................................................................... 14

6.4.3 Forced discharge ........................................................................................... 14

6.4.4 Internal short-circuit test ................................................................................ 15

Annex A (informative) Operating region of cells for safe use ................................................ 17

A.1 General ................................................................................................................. 17

A.2 Charging conditions for safe use ........................................................................... 17

A.2.1 General ......................................................................................................... 17

A.2.2 Consideration on charging voltage ................................................................. 17

A.2.3 Consideration on temperature ........................................................................ 18

A.3 Example of operating region ................................................................................. 19

Annex B (informative) Explanation for the internal short-circuit test ...................................... 20

B.1 General concept ................................................................................................... 20

B.2 Internal short-circuit caused by the particle contamination .................................... 20

Annex C (normative) Alternative internal short-circuit test (6.4.4.2.2) ................................... 22

C.1 General ................................................................................................................. 22

C.2 Test preparation and test set-up ........................................................................... 22

C.2.1 Preparation of cell before the test .................................................................. 22

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IEC 62660-3:2022 © IEC 2022 – 3 –

C.2.2 Test setup ..................................................................................................... 24

C.2.3 Preliminary test ............................................................................................. 25

C.3 Test procedure ...................................................................................................... 26

C.4 Acceptance criteria ............................................................................................... 26

Bibliography .......................................................................................................................... 27

Figure 1 – Example of temperature measurement of cell ....................................................... 10

Figure 2 – Example of crush test ........................................................................................... 13

Figure A.1 – An example of operating region for charging of typical lithium-ion cells ............. 19

Figure A.2 – An example of operating region for discharging of typical lithium-ion cells ........ 19

Figure C.1 – Example of case thinning .................................................................................. 22

Figure C.2 – Example of thinning tool ................................................................................... 23

Figure C.3 – Example of removing hard case ........................................................................ 23

Figure C.4 – Example of hard case removal method during cell manufacturing ..................... 23

Figure C.5 – Example of fixation of cell ................................................................................. 24

Figure C.6 – Test setup image for voltage measurement ....................................................... 24

Figure C.7 – Example of abrupt voltage drop ........................................................................ 25

Table B.1 – Examples of the internal short-circuit of cell ....................................................... 20

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– 4 – IEC 62660-3:2022 © IEC 2022
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
SECONDARY LITHIUM-ION CELLS FOR THE PROPULSION
OF ELECTRIC ROAD VEHICLES –
Part 3: Safety requirements
FOREWORD

1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising

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8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is

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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.

IEC 62660-3 has been prepared by IEC technical committee 21: Secondary cells and batteries.

It is an International Standard.

This second edition cancels and replaces the first edition published in 2016. This edition

constitutes a technical revision.

This edition includes the following significant technical changes with respect to the previous

edition:

a) The new method for the internal short-circuit test has been added in 6.4.4.2.2 and Annex C,

as an alternative option to the test in 6.4.4.2.1.
b) The vibration test has been deleted.
c) The test conditions of overcharge (6.4.2.2) have been partially revised.
---------------------- Page: 6 ----------------------
IEC 62660-3:2022 © IEC 2022 – 5 –
The text of this International Standard is based on the following documents:
Draft Report on voting
21/1133/FDIS 21/1137/RVD

Full information on the voting for its approval can be found in the report on voting indicated in

the above table.
The language used for the development of this International Standard is English.

This document was drafted in accordance with ISO/IEC Directives, Part 2, and developed in

accordance with ISO/IEC Directives, Part 1 and ISO/IEC Directives, IEC Supplement, available

at www.iec.ch/members_experts/refdocs. The main document types developed by IEC are

described in greater detail at www.iec.ch/standardsdev/publications.

A list of all 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 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 document 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.

---------------------- Page: 7 ----------------------
– 6 – IEC 62660-3:2022 © IEC 2022
SECONDARY LITHIUM-ION CELLS FOR THE PROPULSION
OF ELECTRIC ROAD VEHICLES –
Part 3: Safety requirements
1 Scope

This part of IEC 62660 specifies test procedures and acceptance criteria for safety performance

of secondary lithium-ion cells and cell blocks used for propulsion of electric vehicles (EV)

including battery electric vehicles (BEV) and hybrid electric vehicles (HEV).

This document determines the basic safety performance of cells used in a battery pack and

system under intended use and reasonably foreseeable misuse or incident, during the normal

operation of the EV. The safety requirements of the cell in this document are based on the

premise that the cells are properly used in a battery pack and system within the limits for voltage,

current and temperature as specified by the cell manufacturer (cell operating region).

The evaluation of the safety of cells during transport and storage is not covered by this

document.

NOTE 1 The safety performance requirements for lithium-ion battery packs and systems are defined in ISO 6469‑1.

The specifications and safety requirements for lithium-ion battery packs and systems of electrically propelled mopeds

and motorcycles are defined in ISO 18243. IEC 62619 covers the safety requirements for the lithium-ion cells and

batteries for industrial applications, including, for example, forklift trucks, golf carts, and automated guided vehicles.

NOTE 2 Lithium cells, modules, battery packs, and battery systems are regulated by International Air Transport

Association (IATA) and International Maritime Organization (IMO) for air and sea transport, and, regionally, by other

authorities, mainly for land transport. Refer to IEC 62281 for additional information.

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 62619:— , Secondary cells and batteries containing alkaline or other non-acid electrolytes

– Safety requirements for secondary lithium cells and batteries, for use in industrial applications

IEC 62660-2:2018, Secondary lithium-ion cells for the propulsion of electric road vehicles –

Part 2: Reliability and abuse testing
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.
___________

Second edition under preparation. Stage at the time of publication: IEC FDIS 62619:2021.

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IEC 62660-3:2022 © IEC 2022 – 7 –

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
BEV
battery electric vehicle

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)) and not yet fitted with its final

housing, terminal arrangement or electronic control device
3.3
cylindrical cell

cell with a cylindrical shape in which the overall height is equal to or greater than the diameter

[SOURCE: IEC 60050-482:2004, 482-02-39]
3.4
explosion

failure that occurs when a cell container opens violently and its solid contents are forcibly

expelled
3.5
fire
emission of flames from a cell or cell block for more than 1 s
Note 1 to entry: Sparks and arcing are not considered as flames.
3.6
HEV
hybrid electric vehicle

vehicle with both a rechargeable energy storage system and a fuelled power source for

propulsion
3.7
internal short-circuit

unintentional electrical connection between the negative and positive electrodes inside a cell

3.8
leakage

visible escape of liquid electrolyte from a part, except for a vent, such as the case, sealing part,

and/or terminals of the cell
3.9
nominal voltage
suitable approximate value of the voltage used to designate or identify a cell
[SOURCE: IEC 60050-482:2004, 482-03-31, modified – Deletion of "a battery or an
electrochemical system" at the end of the definition.]
---------------------- Page: 9 ----------------------
– 8 – IEC 62660-3:2022 © IEC 2022
3.10
pouch cell

cell having the shape of a parallelepiped whose faces are rectangular and with a prismatic

flexible laminate film case
3.11
prismatic cell

cell having the shape of a parallelepiped whose faces are rectangular and with a prismatic hard

case

[SOURCE: IEC 60050-482:2004, 482-02-38, modified − The word "cell" has been added to the

term, "qualifies a cell or a battery" has been replaced with "cell" in the definition, and "and with

a prismatic hard case housing" has been added.]
3.12
rated capacity

capacity value of a cell in ampere hours (Ah) determined under specified conditions and

declared by the cell manufacturer

Note 1 to entry: The subscript n in C is the time base in hours (h). In this document, n = 3 for BEV application and

n = 1 for HEV application unless otherwise specified.
Note 2 to entry: Term and definition based on IEC 60050-482:2004, 482-03-15.
3.13
reference test current
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, Clause 2.
3.14
rupture

mechanical failure of a container case of a cell induced by an internal or external cause,

resulting in exposure or spillage but not ejection of materials
3.15
secondary lithium-ion cell

secondary single cell whose electrical energy is derived from the insertion/extraction reactions

of lithium-ions between the negative electrode and the positive electrode

Note 1 to entry: A secondary cell is a manufactured unit providing a source of electrical energy by direct conversion

of chemical energy. The cell consists of electrodes, electrolyte, container, terminals and, if any, separators. The

electrode can be monopolar or bipolar; the current collector of the former has active material of single polarity and

the latter has positive and negative electrode active materials. The electrolyte includes an ionic conductive liquid or

solid, or a mixture of them. The cell is designed to be charged electrically.

Note 2 to entry: Where the term "cell" is used alone in this document, it refers to a secondary lithium-ion cell.

3.16
SOC
state of charge

quantity of electricity stored in a cell expressed as a percentage of rated capacity

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IEC 62660-3:2022 © IEC 2022 – 9 –
3.17
upper limit charging voltage

highest charging voltage in the cell operating region, which is specified by the cell manufacturer

Note 1 to entry: Information on the cell operating region is provided in Annex A.

[SOURCE: IEC 62133-2:2017, 3.19, modified − Note to entry added.]
3.18
venting

release of excessive internal pressure from a cell in a manner intended by design to preclude

rupture or explosion
4 Test conditions
4.1 General

Unless otherwise stated in this document, cells shall be tested at room temperature. For the

purposes of this document, room temperature is 25 °C ± 2 K.

The details of the instrumentation used shall be provided in any report of results.

Cell blocks can be tested as an alternative to cells in accordance with the agreement between

the cell manufacturer and the customer.

Concerning the cell for plug-in hybrid electric vehicles (PHEV), the cell manufacturer can select

either the test condition of BEV application or of HEV application.

NOTE Test and measurement can be conducted in a fixture as 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.
---------------------- Page: 11 ----------------------
– 10 – IEC 62660-3:2022 © IEC 2022

The examples for temperature measurement are shown in Figure 1. The instructions for

temperature measurement specified by the cell manufacturer shall be followed.
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 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 stabilization 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 l
...