IEC 63370:2022

Lithium-ion batteries and charging systems - Safety

IEC 63370:2022 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.
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).

Batteries lithium-ion et systèmes de charge – Sécurité

IEC 63370:2022 Le présent document inclut un sous-ensemble des exigences de l'IEC 62841-1:2014 qui s'appliquent aux systèmes de charge de batteries. Le système de charge de batterie se compose d'une ou de plusieurs batteries, ainsi que de leurs circuits de charge associés. Dans de nombreux cas, le même système de charge de batterie est utilisé pour une vaste gamme de produits finaux. Par conséquent, l'objet du présent document est de fournir un moyen d'évaluer le système de charge de batterie destiné aux outils électroportatifs à moteur, aux outils portables, ainsi qu'aux machines pour jardins et pelouses. Cette évaluation pourra alors être appliquée à une vaste gamme de produits traités par l'IEC 62841 (toutes les parties) sans nécessiter une réévaluation du système de charge de batterie pour chaque cas où celui-ci est utilisé dans ou avec un produit. Le présent document s'applique à la sécurité des batteries lithium-ion et des systèmes de charge associés qui sont destinés à être utilisés dans les produits à entraînement magnétique ou à moteur alimentés par des batteries rechargeables, tels que les:
outils électroportatifs (IEC 62841-2);
outils portables (IEC 62841-3);
machines pour jardins et pelouses (IEC 62841-4).

General Information

• Status: Published
• Publication Date: 25-Apr-2022
• ICS: 25.140.20 - Electric tools
• Technical Committee: TC 116 - Safety of motor-operated electric tools
• Current Stage: PPUB - Publication issued
• Completion Date: 26-Apr-2022

Standards Content (sample)

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
IEC 63370:2022-04(en-fr)
---------------------- Page: 1 ----------------------
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---------------------- Page: 2 ----------------------
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

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 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

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IEC 63370:2022 © IEC 2022 – 3 –
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,

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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

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

indispensable for the correct application of this publication.

9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of patent

rights. IEC shall not be held responsible for identifying any or all such patent rights.

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.
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– 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.
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IEC 63370:2022 © IEC 2022 – 5 –
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.

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– 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).
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IEC 63370:2022 © IEC 2022 – 7 –

– 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
---------------------- Page: 9 ----------------------
– 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.
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IEC 63370:2022 © IEC 2022 – 9 –

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.
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– 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 c
...