IEC 61960-4:2020

Secondary cells and batteries containing alkaline or other non-acid electrolytes - Secondary lithium cells and batteries for portable applications - Part 4: Coin secondary lithium cells, and batteries made from them

IEC 61960-4:2020 specifies performance tests, designations, markings, dimensions and other requirements for coin secondary lithium cells and batteries for portable applications and backup power supply such as memory backup applications.
The objective of this document is to provide the purchasers and users of coin secondary lithium cells and batteries with a set of criteria with which they can assess the performance of coin secondary lithium cells and batteries offered by various manufacturers.
This document defines a minimum required level of performance and a standardized methodology by which testing is performed and the results of this testing reported to the user. Hence, users will be able to establish the viability of commercially available cells and batteries via the declared specification and thus be able to select the cell or battery best suited for their intended application.
This document covers coin secondary lithium cells and batteries with a range of chemistries. Each electrochemical couple has a characteristic voltage range over which, during discharge, it releases its electrical capacity, a characteristic nominal voltage and a characteristic end-of-discharge voltage. Users of coin secondary lithium cells and batteries are requested to consult the manufacturer for advice.
This document also provides guidelines for designers of equipment using lithium batteries.

Accumulateurs alcalins et autres accumulateurs à électrolyte non acide - Accumulateurs au lithium pour applications portables - Partie 4: Éléments et batteries d’accumulateurs boutons au lithium

L'IEC 61960-4:2020 spécifie les essais de performance, les désignations, les marquages, les dimensions et autres exigences pour les éléments et batteries d'accumulateurs boutons au lithium destinés aux applications portables et d'alimentation de secours telles que les applications de sauvegarde de mémoire.
L'objectif du présent document est de fournir aux acheteurs et aux utilisateurs d'éléments et batteries d'accumulateurs boutons au lithium un ensemble de critères au moyen desquels ils peuvent évaluer la performance des différents accumulateurs de ce type proposés par différents fabricants.
Le présent document définit un niveau d'exigence minimale de performance et une méthodologie normalisée par laquelle sont réalisés les essais dont les résultats sont mis à la disposition de l'utilisateur. Les utilisateurs sont alors en mesure d'apprécier par eux-mêmes la viabilité des accumulateurs disponibles dans le commerce au moyen de la spécification déclarée et donc de sélectionner l'élément ou la batterie le ou la mieux adapté(e) à l'application prévue.
Le présent document concerne les éléments et batteries d'accumulateurs boutons au lithium dans une large gamme de couples électrochimiques. Chaque couple électrochimique possède une plage de tension caractéristique dans laquelle il restitue, en décharge, sa capacité emmagasinée, une tension nominale caractéristique et une tension de fin de décharge caractéristique. Il est demandé aux utilisateurs d'éléments et batteries d'accumulateurs boutons au lithium de prendre conseil auprès du fabricant.
Le présent document fournit également des lignes directrices pour les concepteurs d'équipements utilisant des batteries au lithium.

General Information

• Status: Published
• Publication Date: 19-Apr-2020
• ICS: 29.220.99 - Other cells and batteries
• Technical Committee: SC 21A - Secondary cells and batteries containing alkaline or other non-acid electrolytes
• Drafting Committee: WG 3 - TC 21/SC 21A/WG 3
• Current Stage: DELPUB - Deleted Publication
• Start Date: 30-Jul-2024
• Completion Date: 24-Jun-2022

Relations

• Replaces: IEC 61960:2011 - Secondary cells and batteries containing alkaline or other non-acid electrolytes - Secondary lithium cells and batteries for portable applications
• Effective Date: 05-Sep-2023
• Revised: IEC 61960-4:2024 - Secondary cells and batteries containing alkaline or other non-acid electrolytes - Secondary lithium cells and batteries for portable applications - Part 4: Coin secondary lithium cells, and batteries made from them
• Effective Date: 05-Sep-2023

Standards Content (Sample)

IEC 61960-4 ®
Edition 1.0 2020-04
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Secondary cells and batteries containing alkaline or other non-acid electrolytes –
Secondary lithium cells and batteries for portable applications –
Part 4: Coin secondary lithium cells, and batteries made from them

Accumulateurs alcalins et autres accumulateurs à électrolyte non acide –
Accumulateurs au lithium pour applications portables –
Partie 4: Éléments et batteries d'accumulateurs boutons au lithium

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IEC 61960-4 ®
Edition 1.0 2020-04
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Secondary cells and batteries containing alkaline or other non-acid electrolytes –

Secondary lithium cells and batteries for portable applications –

Part 4: Coin secondary lithium cells, and batteries made from them

Accumulateurs alcalins et autres accumulateurs à électrolyte non acide –

Accumulateurs au lithium pour applications portables –

Partie 4: Éléments et batteries d'accumulateurs boutons au lithium

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 29.220.99 ISBN 978-2-8322-8069-0

– 2 – IEC 61960-4:2020 © IEC 2020
CONTENTS
FOREWORD . 3
1 Scope . 5
2 Normative references . 5
3 Terms and definitions . 5
4 Parameter measurement tolerances . 7
5 Cell designation and marking . 7
5.1 Cell designation . 7
5.2 Marking . 9
5.2.1 General . 9
5.2.2 Small cells or batteries . 9
6 Electrical tests . 9
6.1 General . 9
6.2 Charging procedure for test purposes . 10
6.3 Discharge performance . 11
6.4 Charge (capacity) recovery after long-term storage . 12
6.5 Endurance in cycles . 12
6.6 Cell or battery internal resistance (AC resistance) . 13
6.6.1 General . 13
6.6.2 Test – General . 13
6.6.3 Measurement . 13
6.6.4 Acceptance criterion . 14
7 Differentiation . 14
Annex A (informative) Guidelines for designers of equipment using lithium batteries . 15
Bibliography . 16

Figure 1 – Dimensional characteristics . 8
Figure 2 – Sample sizes and sequence of tests . 10

Table 1 – Electrochemical systems in current practical use . 8
Table 2 – Examples of recommended upper limit charge voltage . 11
Table 3 – Recommended end-of-discharge voltage limit . 11
Table 4 – Minimum number of cycles . 13
Table A.1 – Equipment design guidelines . 15

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
SECONDARY CELLS AND BATTERIES CONTAINING ALKALINE OR
OTHER NON-ACID ELECTROLYTES – SECONDARY LITHIUM CELLS
AND BATTERIES FOR PORTABLE APPLICATIONS –

Part 4: Coin secondary lithium cells, and batteries made from them

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 this end and
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rights. IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 61960-4 has been prepared by subcommittee 21A: Secondary cells
and batteries containing alkaline or other non-acid electrolytes, of IEC technical committee 21:
Secondary cells and batteries.
The text of this International Standard is based on the following documents:
FDIS Report on voting
21A/725/FDIS 21A/726/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.

– 4 – IEC 61960-4:2020 © IEC 2020
A list of all parts in the IEC 61960 series, published under the general title Secondary cells and
batteries containing alkaline or other non-acid electrolytes – Secondary lithium cells and
batteries for portable applications, 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.
SECONDARY CELLS AND BATTERIES CONTAINING ALKALINE OR
OTHER NON-ACID ELECTROLYTES – SECONDARY LITHIUM CELLS
AND BATTERIES FOR PORTABLE APPLICATIONS –

Part 4: Coin secondary lithium cells, and batteries made from them

1 Scope
This part of IEC 61960 specifies performance tests, designations, markings, dimensions and
other requirements for coin secondary lithium cells and batteries for portable applications and
backup power supply such as memory backup applications.
The objective of this document is to provide the purchasers and users of coin secondary lithium
cells and batteries with a set of criteria with which they can assess the performance of coin
secondary lithium cells and batteries offered by various manufacturers.
This document defines a minimum required level of performance and a standardized
methodology by which testing is performed and the results of this testing reported to the user.
Hence, users will be able to establish the viability of commercially available cells and batteries
via the declared specification and thus be able to select the cell or battery best suited for their
intended application.
This document covers coin secondary lithium cells and batteries with a range of chemistries.
Each electrochemical couple has a characteristic voltage range over which, during discharge,
it releases its electrical capacity, a characteristic nominal voltage and a characteristic end-of-
discharge voltage. Users of coin secondary lithium cells and batteries are requested to consult
the manufacturer for advice.
This document also provides guidelines for designers of equipment using lithium batteries (see
Annex A).
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 60050-482:2004, International Electrotechnical Vocabulary (IEV) – Part 482: Primary and
secondary cells and batteries
IEC 62133-2:2017, Secondary cells and batteries containing alkaline or other non-acid
electrolytes – Safety requirements for portable sealed secondary cells, and for batteries made
from them, for use in portable applications – Part 2: Lithium systems
3 Terms and definitions
For the purposes of this document, the terms and definitions given in IEC 60050-482 and the
following apply.
– 6 – IEC 61960-4:2020 © IEC 2020
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
charge recovery
capacity recovery
capacity that a cell or battery can deliver with subsequent recharge, after storage at a specific
temperature, for a specific time, as a percentage of the rated capacity
3.2
coin cell
coin battery
small round cell or battery where the overall height is less than the diameter, containing
non-aqueous electrolyte
3.3
end-of-discharge voltage
specified closed circuit voltage at which a discharge of a cell or battery is terminated
[SOURCE: IEC 60050-482:2004, 482-03-30, modified – The synonyms "final voltage", "cut-off
voltage", and "end-point voltage" have been omitted and the words "closed circuit" and "cell"
have been added to the definition.]
3.4
nominal voltage
suitable approximate value of voltage used to designate or identify a cell, or a battery
Note 1 to entry: The nominal voltages of coin secondary lithium cells are shown in Table 1.
[SOURCE: IEC 60050-482:2004, 482-03-31, modified – "electrochemical system" has been
omitted from the definition and the note has been added.]
3.5
rated capacity
quantity of electricity mAh (milliampere-hours) that a single cell or battery can deliver, when
charged, stored and discharged under specified conditions and declared by the manufacturer
3.6
secondary lithium battery
unit which incorporates one or more secondary lithium cells and which is ready for use
Note 1 to entry: This unit incorporates adequate housing and a terminal arrangement and may have electronic
control devices.
3.7
secondary lithium cell
secondary cell whose electrical energy is derived from oxidation and the reduction of lithium
Note 1 to entry: This cell is not ready for use in an application because it is not yet fitted with its final housing,
terminal arrangement and electronic control device.

4 Parameter measurement tolerances
The overall accuracy of controlled or measured values, relative to the specified or actual values,
shall be within the following tolerances:
a) ±1 % for voltage;
b) ±1 % for current;
c) ±1 % for capacity;
d) ±2 °C for temperature;
e) ±0,1 % for time;
f) ±0,1 mm for dimensions.
These tolerances comprise the combined accuracy of the measuring instruments, the
measurement techniques used, and all other sources of error in the test procedure.
The details of the instrumentation used shall be provided in any report of results.
5 Cell designation and marking
5.1 Cell designation
Cells shall be designated with the following form:
A A DDHH
1 2
where
A designates the positive electrode system in which:
C or U is lithium cobalt oxide
M is lithium manganese oxide
NB is niobium oxide
V is vanadium oxide
T is lithium titanium oxide
A designates the negative electrode system in which:
C is carbon
L is lithium aluminium alloy
S is lithium silicon oxide/alloy
T or TL is lithium titanium oxide
DD designates the diameter in mm
HH designates the height in 1/10 of mm
The requirements concerning code letters on electrochemical systems are given in Table 1.

– 8 – IEC 61960-4:2020 © IEC 2020
Table 1 – Electrochemical systems in current practical use
Nominal
voltage
Positive electrode Electrolyte Negative electrode
Code letters
(V)
Lithium cobalt oxide Carbon 3,7 UC
Lithium cobalt oxide Lithium titanium oxide 3,0 UT
Vanadium oxide Lithium aluminium alloy 3,0 VL
Lithium manganese oxide Lithium aluminium alloy 3,0 ML
Lithium manganese oxide Lithium silicon oxide/alloy 3,0 MS
Non-aqueous
Lithium cobalt oxide solution with Lithium titanium oxide 2,3 CTL
lithium salt
Niobium oxide Lithium aluminium alloy 2,0 NBL
Lithium manganese oxide Lithium titanium oxide 1,5 MT
Lithium titanium oxide Lithium-carbon compound 1,5 TC
Lithium titanium oxide Lithium aluminium alloy 1,5 TL
Lithium titanium oxide Lithium silicon oxide 1,5 TS
The above code letters are given as examples. Each positive electrode and negative electrode shall be designated with
one or two letters. Any code letter can be decided on by agreement between the manufacturer and user when there is a
same chemistry which has different nominal voltages.

Key
h overall height of the cell
d diameter of the cell
Figure 1 – Dimensional characteristics
Coin secondary lithium cells complying with this document shall be designated by the following
system consisting of code letters and numbers. For the electrochemical systems, the code
letters shall be expressed using two letters (a maximum of three letters), followed by diameter
and height expressed in that order. See Figure 1.
EXAMPLE                                   ML 1220

Electrochemical systems code letters
Dimensions: d in millimetres
Dimensions: h in 1/10 of millimetres
NOTE Notwithstanding the above specification, other designations can be used according to an agreement between
manufacturer and user.
5.2 Marking
5.2.1 General
With the exception of small cells or batteries (see 5.2.2), each cell or battery shall be marked
with the following information:
a) cell designation, IEC or common;
b) the year and month or week of manufacture (may be given in code);
c) polarity of the positive (+) terminal;
d) nominal voltage;
e) name or trade mark of the manufacturer or supplier;
f) cautionary advice;
g) caution for ingestion of swallowable cells and batteries (see IEC 60086-4);
h) combination of "secondary (rechargeable)" and "Li", or "secondary (rechargeable)" and "Li-
ion".
5.2.2 Small cells or batteries
For cells or batteries that fit entirely within the ingestion gauge (Figure 3 in IEC 62133-2:2017),
the designation specified in 5.2.1 a) and the polarity specified in 5.2.1 c) shall be marked on
the cell or battery.
For cells or batteries with an internal AC resistance less than or equal to 3 Ω, intended to be
user replaceable or not contained in the equipment, the additional marking of 5.2.1 h) shall be
marked on the cell or battery.
All other information shown in 5.2.1 should be given in the specification sheet, or in the
instruction manual or on the immediate package instead of on the cell or battery.
6 Electrical tests
6.1 General
Only cell or battery samples which are less than two months (60 days) old from the date of
manufacture shall be used for the tests specified in this document.
Unless otherwise stated in this document, the following tests shall be done in an ambient
temperature of 20 °C ± 5 °C.
Tested cells or batteries should not exceed the upper limit charge voltage or end-of-discharge
voltage limit during the test.
Coin secondary lithium cells or batteries have different characteristics and features in terms of
voltage, discharge performance, capacity recovery after storage, and cycling depending on their
chemistries. Therefore, conditions specified by the manufacturer shall be used in order to make
the most of cell or battery characteristics.
The sample sizes and the sequence of the tests are described in Figure 2.

– 10 – IEC 61960-4:2020 © IEC 2020

Figure 2 – Sample sizes and sequence of tests
6.2 Charging procedure for test purposes
There are two different charging methods for the coin secondary lithium cells or batteries:
constant voltage charge and constant current charge. The charge method and conditions
specified by the manufacturer shall be used. When such information is not available, the charge
voltage shall be in accordance with Table 2.

Table 2 – Examples of recommended upper limit charge voltage
Recommended upper limit
Code letters
charge voltage
UC 4,25 V
UT 3,2 V
VL 3,55 V
ML 3,2 V
MS 3,3 V
CTL 2,7 V
NBL 2,5 V
MT 2,6 V
TC 3,15 V
TL 1,7 V
TS 3,0 V
6.3 Discharge performance
This test verifies the rated capacity of a cell or battery at 20 °C.
Step 1: The cell or battery shall be charged in accordance with 6.2.
Step 2: The cell or battery shall be stored in an ambient temperature of 20 °C ± 5 °C, for not
less than 1 h and not more than 4 h.
Step 3: The cell or battery shall be discharged, in an ambient temperature of 20 °C ± 5 °C, at a
constant current or constant resistance to the end-of-discharge voltage specified by the
manufacturer. When such information is not available, the recommended end-of-discharge
voltage limits are shown in Table 3.
Step 4: The capacity (mAh) delivered during step 3 shall be not less than the rated capacity
declared by the manufacturer.
Table 3 – Recommended end-of-discharge voltage limit
Recommended end-of-discharge
Code letters
voltage limit
UC 2,5 V
UT 2,0 V
VL 2,5 V
ML 2,0 V
MS 2,0 V
CTL 2,0 V
NBL 1,0 V
MT 1,0 V
TC 0,5 V
TL 0,8 V
TS 1,0 V
– 12 – IEC 61960-4:2020 © IEC 2020
6.4 Charge (capacity) recovery after long-term storage
This test verifies the capacity of a cell or battery after extended storage at 100 % state of charge,
followed by a subsequent charge.
Step 1: The cell or battery shall be charged in accordance with the specific conditions specified
by the manufacturer.
Step 2: The cell or battery shall be stored at 60 °C for 20 days.
Step 3: The cell or battery shall be stored, in an ambient temperature of 20 °C ± 5 °C, for not
less than 1 h and not more than 4 h.
Step 4: The cell or battery shall be discharged in an ambient temperature of 20 °C ± 5 °C, at
the discharge conditions specified by manufacturer, until its voltage is equal to the
manufacturer's specified end-of-discharge voltage. The cell or battery shall be charged before
discharge by the specific condition by the manufacturer.
Step 5: The capacity (mAh) delivered during step 4 shall be more than 50 % of its rated capacity.
6.5 Endurance in cycles
This test verifies the ability of charge-discharge cycle.
Step 1: The cell or battery shall be discharged, in an ambient temperature of 20 °C ± 5 °C, using
the method declared by the manufacturer.
Step 2: The cell or battery shall be continuously charged and discharged, in an ambient
temperature of 20 °C ± 5 °C.
The cell or battery shall be charged until its voltage is equal to the specified end-of-charge
voltage, or it shall be charged for the specified amount of time after its voltage is equal to the
specified end-of-charge voltage, using the method and conditions declared by the manufacturer.
The cell or battery shall be discharged in an ambient temperature of 20 °C ± 5 °C, until its
voltage is equal to the specified end-of-discharge voltage, or it shall be discharged for the
specified amount of time, using the method declared by the manufacturer.
The test shall be terminated when the discharge capacity reaches 50 % of its first cycle. The
result shall satisfy the minimum number of cycles in Table 4.

Table 4 – Minimum number of cycles
Code letters Minimum number of cycles
UC 100
UT 100
VL 5
ML 5
MS 50
CTL 100
NBL 5
MT 100
TC 100
TL 5
TS 50
The test procedure in 6.5 is a representative and unified accelerated method
to cover various electrochemical systems, and actual charge-discharge
conditions may be different depending on each application. The above
minimum numbers of cycles are values tested according to the procedure in
6.5. This accelerated test method might result in a fewer number of cycles
than in actual use.
6.6 Cell or battery internal resistance (AC resistance)
6.6.1 General
Internal AC resistance measurement is necessary to evaluate cell performance. When internal
AC resistance is smaller than 3 Ω, the safety standard of IEC 62133-2:2017, Annex D is
applicable.
6.6.2 Test – General
This test verifies the internal resistance of a secondary lithium cell or battery by the alternating
current (AC) method.
The internal resistance shall be measured at conditions (e.g. voltage, temperature) specified
by the manufacturer.
6.6.3 Measurement
The alternating RMS voltage, U , shall be measured while applying an alternating RMS current,
a
I , at the frequency of 1,0 kHz ± 0,1 kHz, to the cell or battery, for a period of 1 s to 5 s.
a
All voltage measurements shall be made at the terminals of the cell or battery independently of
the contacts used to carry current.
The internal AC resistance, R , is given by:
ac
U
a
R = (Ω)
ac
I
a
where
U is the alternating RMS voltage;
a
I is the alternating RMS current.
a
– 14 – IEC 61960-4:2020 © IEC 2020
The alternating current should be selected so that the peak voltage stays below 20 mV.
NOTE This method will in fact measure the impedance which, at the frequency specified, is approximately equal to
the resistance.
6.6.4 Acceptance criterion
The internal AC resistance of the cell or battery shall be not greater than the value of R ,
ac
declared by the manufacturer.
7 Differentiation
Technical consideration shall be taken to prevent coin secondary lithium cells and batteries
from being confused with primary lithium cells and batteries which are similar in appearance
and size. (For example, construction of an attached terminal in such a way that the terminal
cannot be replaced, affixing a note of caution, etc.)
The required information shall be marked on coin secondary lithium cells or batteries in
accordance with 5.2.
Annex A
(informative)
Guidelines for designers of equipment using lithium batteries
Table A.1 – Equipment design guidelines
Possible consequences if the
recommendations are not
Item Sub-item Recommendations
observed
(1) Battery holder and battery a) Battery compartments should Unless protection is provided
compartment be designed so that if a battery against battery reversal, damage
is reversed, open circuit is to equipment can occur from
achieved. Battery resultant electrolyte leakage,
compartments should be overheating, rupture, explosion or
clearly and permanently fire
marked to show the correct
orientation of batteries
b Battery compartments should Equipment might be damaged or
be designed so that batteries of might not operate
sizes other than that specified
cannot be inserted and make
contact
c) Battery compartments should Battery compartments might be
be designed to allow generated damaged when internal pressure
gases to escape of the battery becomes too high
due to gas generation
d) Battery compartments should
be designed to be waterproof
e) Battery compartments should
be designed to be explosion-
proof when tightly sealed
f) Battery compartments should Battery might be deformed and
be isolated from heat leak electrolyte due to excessive
generated by the equipment heat
g) Battery compartments should Children might remove batteries
be designed so that they from the compartment and
cannot easily be opened by swallow them
children
a) Material and shape of contacts Heat might generate at the
(2) Contacts and terminals
and terminals should be contact due to insufficient
selected so that effective connection
electric contact is maintained
b) Auxiliary circuit should be Equipment might be damaged or
designed to prevent reverse might not operate
installation of batteries
c) Contacts and terminals should Equipment might be damaged.
be designed to prevent reverse Battery might cause electrolyte
installation of batteries leakage, overheating, rupture,
explosion or fire
d) Direct soldering or welding to a Battery might leak, overheat,
battery should be avoided rupture, explode or catch fire

– 16 – IEC 61960-4:2020 © IEC 2020
Bibliography
IEC 60051 (all parts), Direct acting indicating analogue electrical measuring instruments and
their accessories
IEC 60086-1, Primary batteries – Part 1: General
IEC 60086-2, Primary batteries – Part 2: Physical and electrical specifications
IEC 60086-3, Primary batteries – Part 3: Watch batteries
IEC 60086-4:2019, Primary batteries – Part 4: Safety of lithium batteries
IEC 60485, Digital electronic d.c. voltmeters and d.c. electronic analogue-to-digital convertors
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
IEC 61959, Secondary cells and batteries containing alkaline or other non-acid electrolytes –
Mechanical tests for sealed portable secondary cells and batteries
IEC 61960-3, Secondary cells and batteries containing alkaline or other non-acid electrolytes –
Secondary lithium cells and batteries for portable applications – Part 3 – Prismatic and
cylindrical lithium secondary cells, and batteries made from them
IEC 62133 (all parts), Secondary cells and batteries containing alkaline or other non-acid
electrolytes – Safety requirements for portable sealed secondary cells, and for batteries made
from them, for use in portable applications
IEC 62281, Safety of primary and secondary lithium cells and batteries during transport
IEC 62368-1, Audio/video, information and communication technology equipment – Part 1:
Safety requirements
___________
____________
Withdrawn publication
– 18 – IEC 61960-4:2020 © IEC 2020
SOMMAIRE
AVANT-PROPOS . 19
1 Domaine d'application . 21
2 Références normatives . 21
3 Termes et définitions . 22
4 Tolérances de mesure relatives aux paramètres . 23
5 Désignation et marquage des éléments . 23
5.1 Désignation des éléments . 23
5.2 Marquage . 25
5.2.1 Généralités . 25
5.2.2 Éléments ou batteries de petite taille . 25
6 Essais électriques . 25
6.1 Généralités . 25
6.2 Procédure de charge pour les besoins des essais . 26
6.3 Caractéristiques de décharge . 27
6.4 Récupération de charge (capacité) après un stockage de longue durée . 28
6.5 Endurance en cycles . 28
6.6 Résistance interne (résistance en courant alternatif) d'un élément ou d'une
batterie . 29
6.6.1 Généralités . 29
6.6.2 Essai – Généralités . 29
6.6.3 Mesurage . 29
6.6.4 Critère d'acceptation . 30
7 Différenciation . 30
Annexe A (informative) Lignes directrices pour les concepteurs d'équipements
utilisant des batteries au lithium . 31
Bibliographie . 32

Figure 1 – Caractéristiques dimensionnelles . 24
Figure 2 – Taille des échantillons et séquence d'essais . 26

Tableau 1 – Systèmes électrochimiques en utilisation pratique courante . 24
Tableau 2 – Exemples de limite supérieure de la tension de charge recommandée . 27
Tableau 3 – Limite recommandée de la tension de fin de décharge . 27
Tableau 4 – Nombre minimal de cycles . 29
Tableau A.1 – Lignes directrices pour la conception des équipements . 31

COMMISSION ÉLECTROTECHNIQUE INTERNATIONALE
____________
ACCUMULATEURS ALCALINS ET AUTRES ACCUMULATEURS
À ÉLECTROLYTE NON ACIDE – ACCUMULATEURS AU LITHIUM
POUR APPLICATIONS PORTABLES –
Partie 4: Éléments et batteries d'accumulateurs boutons au lithium

AVANT-PROPOS
1) La Commission Electrotechnique Internationale (IEC) est une organisation mondiale de normalisation composée
de l'ensemble des comités électrotechniques nationaux (Comités nationaux de l'IEC). L'IEC a pour objet de
favoriser la coopération internationale pour toutes les questions de normalisation dans les domaines de
l'électricité et de l'électronique. À cet effet, l'IEC – entre autres activités – publie des Normes internationales,
des Spécifications techniques, des Rapports techniques, des Spécifications accessibles au public (PAS) et des
Guides (ci-après dénommés "Publication(s) de l'IEC"). Leur élaboration est confiée à des comités d'études, aux
travaux desquels tout Comité national intéressé par le sujet traité peut participer. Les organisations
internationales, gouvernementales et non gouvernementales, en liaison avec l'IEC, participent également aux
travaux. L'IEC collabore étroitement avec l'Organisation Internationale de Normalisation (ISO), selon des
conditions fixées par accord entre les deux organisations.
2) Les décisions ou accords officiels de l'IEC concernant les questions techniques représentent, dans la mesure du
possible, un accord international sur les sujets étudiés, étant donné que les Comités nationaux de l'IEC intéressés
sont représentés dans chaque comité d'études.
3) Les Publications de l'IEC se présentent sous la forme de recommandations internationales et sont agréées
comme telles par les Comités nationaux de l'IEC. Tous les efforts raisonnables sont entrepris afin que l'IEC
s'assure de l'exactitude du contenu technique de ses publications; l'IEC ne peut pas être tenue responsable de
l'éventuelle mauvaise utilisation ou interprétation qui en est faite par un quelconque utilisateur final.
4) Dans le but d'encourager l'uniformité internationale, les Comités nationaux de l'IEC s'engagent, dans toute la
mesure possible, à appliquer de façon transparente les Publications de l'IEC dans leurs publications nationales
et régionales. Toutes divergences entre toutes Publications de l'IEC et toutes publications nationales ou
régionales correspondantes doivent être indiquées en termes clairs dans ces dernières.
5) L'IEC elle-même ne fournit aucune attestation de conformité. Des organismes de certification indépendants
fournissent des services d'évaluation de conformité et, dans certains secteurs, accèdent aux marques de
conformité de l'IEC. L'IEC n'est responsable d'aucun des services effectués par les organismes de certification
indépendants.
6) Tous les utilisateurs doivent s'assurer qu'ils sont en possession de la dernière édition de cette publication.
7) Aucune responsabilité ne doit être imputée à l'IEC, à ses administrateurs, employés, auxiliaires ou mandataires,
y compris ses experts particuliers et les membres de ses comités d'études et des Comités nationaux de l'IEC,
pour tout préjudice causé en cas de dommages corporels et matériels, ou de tout autre dommage de quelque
nature que ce soit, directe ou indirecte, ou pour supporter les coûts (y compris les frais de justice) et les dépenses
découlant de la publication ou de l'utilisation de cette Publication de l'IEC ou de toute autre Publication de l'IEC,
ou au crédit qui lui est accordé.
8) L'attention est attirée sur les références normatives citées dans cette publication. L'utilisation de publications
référencées est obligatoire pour une application correcte de la présente publication.
9) L'attention est attirée sur le fait que certains des éléments de la présente Publication de l'IEC peuvent faire l'objet
de droits de brevet. L'IEC ne saurait être tenue pour responsable de ne pas avoir identifié de tels droits de
brevets et de ne pas avoir signalé leur existence.
La Norme internationale IEC 61960-4 a été établie par le sous-comité 21A: Accumulateurs
alcalins et autres accumulateurs à électrolyte non acide, du comité d'études 21 de l'IEC:
Accumulateurs.
– 20 – IEC 61960-4:2020 © IEC 2020
Le texte de cette Norme internationale est issu des documents suivants:
FDIS Rapport de vote
21A/725/FDIS 21A/726/RVD
Le rapport de vote indiqué dans le tableau ci-dessus donne toute information sur le vote ayant
abouti à l'approbation de cette Norme internationale.
Ce document a été rédigé selon les Directives ISO/IEC, Partie 2.
Une liste de toutes les parties de la série IEC 61960, publiées sous le titre général
Accumulateurs alcalins et autres accumulateurs à électrolyte non acide – Accumulateurs au
lithium pour applications portables, peut être consultée sur le si
...