IEC 63370:2022

IEC 63370 ®
Edition 1.0 2022-04
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Lithium-ion batteries and charging systems – Safety

Batteries lithium-ion et systèmes de charge – Sécurité

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IEC 63370 ®
Edition 1.0 2022-04
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Lithium-ion batteries and charging systems – Safety

Batteries lithium-ion et systèmes de charge – Sécurité

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 25.140.20 ISBN 978-2-8322-1104-5

– 2 – IEC 63370:2022 © IEC 2022
CONTENTS
FOREWORD . 3
INTRODUCTION . 5
1 Scope . 6
2 Normative references . 7
3 Terms and definitions . 9
4 Void . 13
5 General conditions for the tests . 13
6 Void . 15
7 Void . 15
8 Marking and instructions . 15
9 Protection against electric shock . 20
10 Void . 20
11 Void . 20
12 Heating . 20
13 Resistance to heat and fire . 21
14 Void . 23
15 Void . 23
16 Void . 23
17 Void . 23
18 Abnormal operation . 23
19 Mechanical hazards . 28
20 Mechanical strength . 28
21 Construction . 29
22 Internal wiring . 32
23 Components . 33
24 Supply connection and external flexible cords . 34
25 Void . 35
26 Void . 35
27 Screws and connections . 35
28 Creepage distances, clearances and distances through insulation . 35
Bibliography . 37

Figure 1 – Test fingernail . 31
Figure 2 – Measurement of clearances . 36

Table 1 – Minimum creepage distances and clearances between parts of different
potential . 35

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
LITHIUM-ION BATTERIES AND CHARGING SYSTEMS –
SAFETY
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
in addition to other activities, IEC publishes International Standards, Technical Specifications, Technical Reports,
Publicly Available Specifications (PAS) and Guides (hereafter referred to as "IEC Publication(s)"). Their
preparation is entrusted to technical committees; any IEC National Committee interested in the subject dealt with
may participate in this preparatory work. International, governmental and non-governmental organizations liaising
with the IEC also participate in this preparation. IEC collaborates closely with the International Organization for
Standardization (ISO) in accordance with conditions determined by agreement between the two organizations.
2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
consensus of opinion on the relevant subjects since each technical committee has representation from all
interested IEC National Committees.
3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC
Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any
misinterpretation by any end user.
4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
transparently to the maximum extent possible in their national and regional publications. Any divergence between
any IEC Publication and the corresponding national or regional publication shall be clearly indicated in the latter.
5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity
assessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any
services carried out by independent certification bodies.
6) All users should ensure that they have the latest edition of this publication.
7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and
members of its technical committees and IEC National Committees for any personal injury, property damage or
other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and
expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC
Publications.
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.
IEC 63370 has been prepared by IEC technical committee 116: Safety of motor-operated
electric tools. It is an International Standard.
The text of this International Standard is based on the following documents:
Draft Report on voting
116/579/FDIS 116/588/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.

– 4 – IEC 63370:2022 © IEC 2022
In this document, the following print types are used:
– requirements: in roman type;
– test specification: in italic type;
– notes: in smaller roman type.
– words in bold in the text are defined in Clause 3. When a definition concerns an adjective,
the adjective and the associated noun are also in bold.
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.
INTRODUCTION
This document contains a subset of requirements from IEC 62841-1:2014 that are applicable
for battery charging systems. The battery charging system includes the battery(ies) and its
related charging circuitry. In many cases, the same battery charging system is utilized for a
wide variety of end products. Therefore, the purpose of this document is to provide a means for
evaluating a battery charging system for electric motor-operated hand-held tools,
transportable tools and lawn and garden machinery. This evaluation can then be utilized over
a wide range of products covered by IEC 62841 (all parts), without having to re-evaluate the
battery charging system for each case where the battery charging system is utilized in or
with a product.
NOTE This document is structured in a way that other Technical Committees could reference this document in end
product standards. For example, products outside of the scope of IEC 62841 (all parts) often use the same battery
charging systems as in products covered by IEC 62841 (all parts).
This document has been structured so that the clause and subclause numbers are aligned, as
far as practical, with both the main body and Annex K of IEC 62841-1:2014.
The following is a list of subclauses in IEC 62841-1:2014 that do not need to be repeated for
battery charging systems evaluated to this document during product evaluations:
– 8.2, 8.6, 8.12, 8.14, 8.14.1, 20.2, 21.3, 21.22, 21.23, 21.24, 22.1, 22.4, 22.5, 23.1.4, 23.1.5,
23.1.7, 23.1.8, 23.4, 27.2;
– K.8.3, K.8.14.1.1, K.8.14.2, K.9.1, K.9.3, K.9.5, K.12.201, K.13.2, K.13.2.201, K.18.1,
K.18.201, K.18.202, K.19.202, K.20.1, K.20.3.1, K.20.3.2, K.21.202, K.21.203, K.22.2,
K.23.201, K.23.202, K.28.1.
Subclause K.13.1 of IEC 62841-1:2014 may or may not need to be repeated for battery
charging systems evaluated to this document, depending on the temperature used for the test
of 13.1 of this document and the temperature required by K.13.1 of IEC 62841-1:2014.

– 6 – IEC 63370:2022 © IEC 2022
LITHIUM-ION BATTERIES AND CHARGING SYSTEMS –
SAFETY
1 Scope
This document applies to the safety of lithium-ion batteries and charging systems for use in
rechargeable battery-powered motor-operated or magnetically driven
– hand-held tools (IEC 62841-2),
– transportable tools (IEC 62841-3), and
– lawn and garden machinery (IEC 62841-4).
The above listed categories are hereinafter referred to as "products".
NOTE 1 This document is structured in a way that other Technical Committees could reference this document in
end product standards. For example, products outside of the scope of IEC 62841 (all parts) often use the same
battery charging systems as in products covered by IEC 62841 (all parts).
The maximum nominal voltage assigned by the manufacturer for battery packs is 75 V DC.
Electric shock hazard is considered to exist only between parts of opposite polarity, except for
cases where batteries are charged by a non-isolated charger.
Battery packs covered under this document intended to be charged by a non-isolated charger
are evaluated by this document and to the requirements for protection against electric shock
specified in IEC 62841-1:2014. When evaluating a battery pack for protection against electric
shock, creepage distances, clearances and distances through insulation, the battery pack is
fitted to the intended charger.
Since battery packs covered under this document are submitted to different use patterns (such
as rough use, high charging and discharging currents), their safety can be evaluated only by
this document or by IEC 62841-1:2014 and not by using other standards for battery packs,
such as IEC 62133-2:2017, unless otherwise indicated in this document. All relevant aspects
related to the safety of batteries are addressed in this document, such that the requirements
of IEC 62133-2:2017 need not be separately applied.
For integral batteries, this document only applies to the integral battery when in combination
with the product.
When evaluating the risk of fire associated with batteries, consideration has been given to the
fact that these batteries are unattended energy sources and have been evaluated as such in
this document. Requirements in other documents regarding the risk of fire due to the charging
of these batteries are therefore considered to be fulfilled.
The following is considered within the context of these requirements.
– These requirements address the risk of fire or explosion of these batteries and not any
possible hazards associated with toxicity nor potential hazards associated with
transportation or disposal.
NOTE 2 IEC 62281:2019 covers the safety aspects of lithium-ion batteries during transport.
– Batteries and charging systems covered by these requirements are not intended to be
serviced by the end user.
– This document is intended to provide an evaluation of the combination of a battery(ies) and
its corresponding charging system(s).

– This document addresses the safety of lithium-ion batteries and charging systems during
storage, use and charging. These requirements are only considered to be supplementary
requirements in regards to battery charger fire and electric shock.
– This document refers to and requires parameters supplied in reference to the cells that
establish conditions for safe use of those cells. Those parameters form the basis of
acceptance criteria for a number of tests contained herein. This document does not
independently evaluate the safety of cells. These parameters, taken as a set, constitute the
"specified operating region" for a cell. There may be several sets of specified operating
region(s).
This document is not intended to apply to general purpose batteries.
This document does not apply to the safety of battery chargers themselves. However, this
document covers the safe functioning of lithium-ion batteries and charging systems.
For a battery(ies) intended to be charged by stand-alone battery chargers, the risks
associated with a mains connection is addressed by the relevant battery charger standard. For
products that incorporate power conversion circuitry for the purposes of providing an energy
source for charging, the protection against the risks associated with a mains is addressed in
the relevant product standard.
NOTE 3 IEC 60335-2-29:2016 and IEC 60335-2-29:2016/AMD1:2019 cover a variety of stand-alone chargers.
This document does not include safety requirements for the battery when incorporated into the
product with respect to heating and mechanical strength. It is possible additional testing needs
to be conducted in accordance with the relevant end product standard.
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 60068-2-75:1997, Environmental testing – Part 2-75: Tests – Test Eh: Hammer tests
IEC TR 60083, Plugs and socket-outlets for domestic and similar general use standardized in
member countries of IEC
IEC 60127 (all parts), Miniature fuses
IEC 60320 (all parts), Appliance couplers for household and similar general purposes
IEC 60320-1, Appliance couplers for household and similar general purposes – Part 1: General
requirements
IEC 60384-14, Fixed capacitors for use in electronic equipment – Part 14: Sectional
specification – Fixed capacitors for electromagnetic interference suppression and connection
to the supply mains
IEC 60417, Graphical symbols for use on equipment (available at http://www.graphical-
symbols.info/equipment)
IEC 60664-1, Insulation coordination for equipment within low-voltage systems – Part 1:
Principles, requirements and tests

– 8 – IEC 63370:2022 © IEC 2022
IEC 60695-2-11:2000, Fire hazard testing – Part 2-11: Glowing/hot-wire based test methods –
Glow-wire flammability test method for end-products (GWEPT)
IEC 60695-2-13:2010, Fire hazard testing – Part 2-13: Glowing/hot-wire based test methods –
Glow-wire ignition temperature (GWIT) test method for materials
IEC 60695-10-2:2003, Fire hazard testing – Part 10-2: Abnormal heat – Ball pressure test
method
IEC 60695-11-10:2013, Fire hazard testing – Part 11-10: Test flames – 50 W horizontal and
vertical flame test methods
IEC 60730-1:2010, Automatic electrical controls – Part 1: General requirements
IEC 60884 (all parts), Plugs and socket-outlets for household and similar purposes
IEC 60906-1, IEC system of plugs and socket-outlets for household and similar purposes –
Part 1: Plugs and socket-outlets 16 A 250 V a.c.
IEC 61000-4-2:2008, Electromagnetic compatibility (EMC) – Part 4-2: Testing and
measurement techniques – Electrostatic discharge immunity test
IEC 61000-4-3:2006, Electromagnetic compatibility (EMC) – Part 4-3: Testing and
measurement techniques – Radiated, radio-frequency, electromagnetic field immunity test
IEC 61000-4-3:2006/AMD1:2007
IEC 61000-4-3:2006/AMD2:2010
IEC 61032:1997, Protection of persons and equipment by enclosures – Probes for verification
IEC 61558-1, Safety of transformers, reactors, power supply units and combinations thereof –
Part 1: General requirements and tests
IEC 61558-2-4, Safety of transformers, reactors, power supply units and similar products for
supply voltages up to 1 100 V – Part 2-4: Particular requirements and tests for isolating
transformers and power supply units incorporating isolating transformers
IEC 61558-2-6, Safety of transformers, reactors, power supply units and similar products for
supply voltages up to 1 100 V – Part 2-6: Particular requirements and tests for safety isolating
transformers and power supply units incorporating safety isolating transformers
____________
This publication has been withdrawn.
This publication has been withdrawn.
This publication has been withdrawn.
This publication has been withdrawn.
This publication has been withdrawn.
This publication has been withdrawn.
This publication has been withdrawn.

IEC 61558-2-16, Safety of transformers, reactors, power supply units and similar products for
supply voltages up to 1 100 V – Part 2-16: Particular requirements and tests for switch mode
power supply units and transformers for switch mode power supply units
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 61960-4, 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 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
IEC 62841-1:2014, Electric motor-operated hand-held tools, transportable tools and lawn and
garden machinery – Safety – Part 1: General requirements
ISO 2768-1, General tolerances – Part 1: Tolerances for linear and angular dimensions without
individual tolerance indications
ISO 3864-2, Graphical symbols – Safety colours and safety signs – Part 2: Design principles
for product safety labels
ISO 7000, Graphical symbols for use on equipment (available at http://www.graphical-
symbols.info/equipment)
ISO 7010, Graphical symbols – Safety colours and safety signs – Registered safety signs
(available at https://www.iso.org/obp)
ISO 13849-1, Safety of machinery – Safety-related parts of control systems – Part 1: General
principles for design
UL 969, Standard for marking and labeling systems
3 Terms and definitions
For the purposes of this document, the following terms and definitions 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
accessible part
conductive part or surface of insulating materials that can be touched by means of the test
probe B of IEC 61032:1997
____________
This publication has been withdrawn.

– 10 – IEC 63370:2022 © IEC 2022
3.2
battery
assembly of one or more cells intended to provide electrical current to the product
3.3
cell
basic functional electrochemical unit containing an assembly of electrodes, electrolyte,
container, terminals, and usually separators, which is a source of electrical energy by direct
conversion of chemical energy
3.4
charger
part or all of the charging system contained in a separate enclosure
Note 1 to entry: Not all charging systems include a separate charger as in the case where a tool may be charged
utilizing a mains supply cord or may incorporate a plug for attachment to a mains receptacle. As a minimum, the
charger includes some of the power conversion circuitry.
3.5
charging system
combination of circuitry intended to charge, balance and/or maintain the state of charge of the
battery
3.6
charring
condition in which untreated 100 % medical gauze is blackened by combustion
Note 1 to entry: Discolouration of untreated 100 % medical gauze caused by smoke is not considered to be
charring.
3.7
clearance
shortest distance between two conductive parts, or between a conductive part and the outer
surface of the enclosure, considered as though metal foil were pressed into contact with
accessible surfaces of insulating material, measured through air
Note 1 to entry: Examples of clearances are given in Annex A of IEC 62841-1:2014.
3.8
creepage distance
shortest path between two conductive parts, or between a conductive part and the outer surface
of the enclosure, considered as though metal foil were pressed into contact with accessible
surfaces of insulating material, measured along the surface of the insulating material
Note 1 to entry: Examples of creepage distances are given in Annex A of IEC 62841-1:2014.
3.9
C rate
current, in amperes, which a cell or battery can be discharged at for 5 h to the voltage cut-off
point specified by the cell manufacturer
3.10
detachable battery pack
battery which is contained in a separate enclosure from the product and is intended to be
removed from the product for charging purposes

3.11
detachable part
part which can be removed or opened without the aid of a tool, or a part which is removed in
accordance with the instruction for use, except externally accessible brush caps, even if
removal requires the use of a tool
Note 1 to entry: A non-detachable part is covered by the requirements of 21.22.
3.12
electronic circuit
circuit incorporating at least one electronic component
3.13
electronic component
part in which conduction is achieved principally by electrons moving through a vacuum, gas or
semiconductor, with the exclusion of neon indicators
Note 1 to entry: Examples of electronic components are diodes, transistors, triacs and monolithic integrated
circuits. Resistors, capacitors and inductors are not considered electronic components.
3.14
explosion
failure that occurs when an enclosure opens violently and major components are forcibly
expelled in a manner that could result in injury
3.15
fire
emission of flames from a battery
3.16
fully charged
cell or battery charged to the maximum state of charge permitted by the battery charging
system intended for use with the product
3.17
fully discharged
battery or cell that has been discharged at C rate until one of the following conditions occurs:
discharge terminates due to protective circuitry or the battery (or cell) reaches a total voltage
with an average voltage per cell equal to the end-of-discharge voltage unless a different end-
of-discharge voltage is specified by the manufacturer
Note 1 to entry: The end-of-discharge voltage for lithium-ion cells is provided in 5.30.
3.18
general purpose
batteries and cells available from a variety of manufacturers, through a variety of outlets
intended for a variety of different manufacturers’ products
Note 1 to entry: 12 V automotive batteries and AA, C and D alkaline cells are examples of general purpose.
3.19
hazardous voltage
voltage between parts having an average value exceeding 60 V DC or exceeding 42,4 V peak
when the peak-to-peak ripple exceeds 10 % of the average value
3.20
integral battery
battery which is contained within the product and is not removed from the product for charging
purposes
– 12 – IEC 63370:2022 © IEC 2022
3.21
lawn and garden machinery
product for garden maintenance
3.22
maximum charging current
highest current that a lithium-ion cell is permitted to pass during charging for a specified range
of temperatures as specified by the cell manufacturer and evaluated in accordance with
IEC 62133-2:2017
3.23
mean time to dangerous failure
MTTF
d
expectation of the mean time to dangerous failure
3.24
normal operation
conditions under which the product or charging system is operated in normal use when it is
connected to the power supply
3.25
normal use
use of a product or charging system for which it is designed, taking into account the
manufacturer’s instructions
3.26
product
electrical device that is powered by a battery
3.27
protective impedance
impedance connected between energized parts and accessible conductive parts, and of a value
so that the current is limited to a safe value
3.28
separable battery pack
battery which is contained in a separate enclosure from the product and is connected to the
product by a cord
3.29
specified operating region
range of permissible operation of lithium-ion cells, expressed by cell parameter limits
3.30
specified operating region for charging
conditions for voltage and current during charging in which the lithium-ion cell is permitted to
operate as specified by the cell manufacturer and evaluated in accordance with
IEC 62133‑2:2017
3.31
temperature limiter
non-self-resetting temperature-sensing device, the operating temperature of which may be
either fixed or adjustable, and which, during normal operation, operates by opening or closing
a circuit when the temperature of the controlled part reaches a predetermined value

3.32
thermal cut-out
device which, during abnormal operation, limits the temperature of the controlled part by
automatically opening the circuit, or by reducing the current, the setting of which cannot be
altered by the user
3.33
thermal link
thermal cut-out which operates only once, and then requires partial or complete replacement
3.34
upper limit charging voltage
highest voltage that a lithium-ion cell is permitted to attain during normal charging for a
specified range of temperatures as specified by the cell manufacturer and evaluated in
accordance with IEC 62133-2:2017
3.35
venting
condition that occurs when a cell releases excessive internal pressure intended by design to
preclude explosion
3.36
working voltage
highest measured RMS value of the AC or DC voltage, without the effect of transient voltages,
across any insulation or between any parts of different potential
Note 1 to entry: Working voltage takes resonant voltages into account.
4 Void
5 General conditions for the tests
5.1 Tests according to this document are type tests. General test conditions in Clause 5 apply
unless otherwise specified in this document.
5.2 The tests are made on separate samples. However, at the manufacturer’s discretion, fewer
samples may be used.
The cumulative stress resulting from successive tests on electronic circuits is to be avoided.
It may be necessary to replace components or to use additional samples.
If several tests are conducted on a single sample, then the results shall not be affected by
previous tests.
5.3 If it is evident from the construction of the battery and/or charging system that a
particular test is not applicable, the test is not made.
5.4 The tests are carried out with the battery and/or charging system, and/or any movable
part of either, placed in the most unfavourable position that may occur in normal use.
5.5 Batteries and charging systems provided with controls or switching devices are tested
with these controls or devices adjusted to their most unfavourable settings, if the setting can be
altered by the user.
5.6 The tests are made in a draught-free location and at an ambient temperature of (20 ± 5) °C.

– 14 – IEC 63370:2022 © IEC 2022
If the temperature attained by any part is limited by a temperature sensitive device, the ambient
temperature is, in case of doubt, maintained at (23 ± 2) °C.
5.7 to 5.11 Void
5.12 When testing electronic circuits, the supply shall be free from those perturbations from
external sources that can influence the results of the tests.
5.13 to 5.17 Void
5.18 If linear and angular dimensions are specified without a tolerance, ISO 2768-1, class "c"
is applicable.
5.19 All electrical measurements shall be made with a maximum measurement error of 5 %.
Instruments for measuring voltage shall have an input resistance of at least 1 MΩ with a
maximum parallel capacitance of 150 pF.
5.20 Void
5.21 When measuring voltage, the peak value of any superimposed ripple exceeding 10 % of
the average value shall be included. Transient voltages are ignored, such as a temporary
increase of voltage, for example after the battery pack is removed from the charger.
5.22 Measurements of cell voltages during the tests of lithium-ion systems shall be made
using a single pole resistive-capacitive low pass filter with a cut-off frequency of
(5 000 ± 500) Hz. If charging voltage limits have been exceeded, the peak value of the voltage
measured after this network shall be used. The measurement shall have a tolerance within ±1 %.
5.23 Some of the tests may result in fire or explosion. It is therefore important that personnel
be protected from the flying fragments, explosive force, sudden release of heat, chemical burns,
intense light and noise that may result from such explosions. The test area shall be well
ventilated to protect personnel from possible harmful fumes or gases.
5.24 Unless otherwise specified, all batteries shall be fully conditioned as follows: batteries
shall be fully discharged and then charged in accordance with the manufacturer’s instructions.
The sequence shall be repeated one more time with an interval of at least two hours after each
discharge.
5.25 The location of thermocouples for lithium-ion cell temperature measurements shall be on
the outer surface, half way along the longest dimension, of the cell that results in the highest
temperature.
5.26 Currents measured during battery charging shall be average currents with an averaging
period of 1 s to 5 s.
5.27 If not otherwise specified, a fully charged battery shall be used. After removal from the
charging system and before starting a test, the fully charged battery shall be allowed to rest
for at least 2 h but no more than 6 h at an ambient temperature of (20 ± 5) °C.
5.28 When a battery comprised of a single cell is employed, instructions in this document
referring to special preparations of a cell in a series configuration shall be ignored.
5.29 For battery designs where there is a series arrangement of parallel clusters of cells, the
cluster shall be treated as a single cell for those tests that require altering the amount of charge
on a single cell prior to conducting the test.

5.30 The end-of-discharge voltage is 2,5 V/cell for lithium-ion batteries.
5.31 For integral batteries, the tests are conducted with the integral battery(ies) installed
in the product.
6 Void
7 Void
8 Marking and instructions
8.1 Void
8.2
NOTE In Canada and the United States of America, the following requirements apply.
Detachable battery packs and separable battery packs must be marked with a safety warning in one of the
following versions:
– " WARNING – To reduce the risk of injury, user must read instruction manual", or
– symbol M002:2011-05 of ISO 7010.
If used, the word "WARNING" must be in capital letters not less than 2,4 mm high and must not be separated from
either the cautionary statement or the symbol ISO 7000-0434A:2004-01 or ISO 7000-0434B:2004-01.
If used, the statement must be verbatim except the term "operator’s manual" or "user guide" may be used for the
term "instruction manual".
If additional symbols are used, they must be in accordance with ISO 7010 or be designed in accordance with
ISO 3864-2 or ISO 3864-3.
Cautionary statements having the same signal word such as " WARNING" may be combined into one paragraph
under one signal word.
Compliance is checked by inspection and by measurement.
8.3 Detachable battery packs and separable battery packs shall be marked with additional
information as follows:
– the business name and address of the manufacturer and, where applicable, his authorised
representative. Any address shall be sufficient to ensure contact. Country or state, city and
postal code (if any) are deemed sufficient for this purpose;
– designation of series or type, allowing the technical identification of the detachable battery
pack and separable battery pack. This may be achieved by a combination of letters and/or
numbers and may be combined with a designation of the detachable battery pack and
separable battery pack.
NOTE 1 The term "designation of series or type" is also known as model number.
Separable battery packs and detachable battery packs shall also be marked with additional
information as follows:
– the capacity assigned by the manufacturer in Ah or mAh, based on the rated capacity of the
cells determined in accordance with IEC 61960-3 or IEC 61960-4;
– the type of battery, i.e. Li-Ion.
NOTE 2 In Canada and the United States of America, the following additional requirements apply.
A detachable battery pack, a separable battery pack, or a battery product provided with an integral battery must
be marked "For use only with ___ charger", or the equivalent, where the underlined space is completed with the
manufacturer's name or trademark, a catalog number, a series identification, or the equivalent, of the charger.

– 16 – IEC 63370:2022 © IEC 2022
Alternatively, the statement "See instruction manual for additional chargers," or the equivalent may be employed in
addition to at least one charger referenced by catalog number.
If additional markings are used, they shall not give rise to misunderstanding.
Compliance is checked by inspection.
8.4 to 8.5 Void
8.6 For units, the following shall be used:
V volts
A amperes
Ah ampere-hours
W watts
Wh watt-hours
kW kilowatts
F farads
μF microfarads
l litres
g grams
kg kilograms
bar bars
Pa pascals
h hours
min minutes
s seconds
For symbols, the following shall be used:
(symbol IEC 60417-5031:2002-10)
or DC
direct current
(symbol IEC 60417-5032:2002-10)
or AC
alternating current
A rated current of the appropriate fuse-link in amperes

x
time-lag miniature fuse-link where X is the symbol for the time/current

characteristic, as given in IEC 60127 (all parts)
(symbol ISO 7000-0434A:2004-01 or ISO 7000-0434B:2004-01)
caution
(symbol M002 of ISO 7010:2011-05)
read the instructions
(symbol IEC 60417-5012:2002-10)
lamp
NOTE The rated wattage of the lamp can be indicated in association with this symbol.
Li-Ion lithium-ion battery
If additional symbols are used, they shall not give rise to misunderstanding and be explained in
the instructions.
When other units are used, the units and their symbols shall be those of the international
standardized system.
Compliance is checked by inspection.
8.7 to 8.11 Void
8.12 Markings required by this document shall be legible and durable. Signs shall be in
contrast such as colour, texture, or relief, to their background such that the information or
instructions provided by the signs are clearly legible when viewed with normal vision from a
distance of (500 + 50) mm. Signs are not r
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