IEC 62928:2017

Railway applications - Rolling stock - Onboard lithium-ion traction batteries

IEC 62928:2017 specifies the design, operation parameters, safety recommendations, data exchange, routine and type tests, as well as marking and designation for onboard lithium-ion traction batteries for railway applications. Battery systems described in this document are used for the energy storage system (ESS) for the traction power of railway vehicles such as hybrid vehicles as defined in IEC 62864-1:2016.

Applications ferroviaires - Matériel roulant - Batteries d'accumulateurs de traction embarquées au lithium-ion

L'IEC 62928:2017 spécifie la conception, les paramètres d'exploitation, les recommandations de sécurité, l'échange de données, les essais individuels de série et les essais de type, ainsi que le marquage et la désignation, pour batteries d'accumulateurs de traction embarquées au lithium-ion destinées aux applications ferroviaires. Les systèmes de batteries décrits dans le présent document sont utilisés dans le cadre du système de stockage de l'énergie afin de fournir une alimentation de traction aux véhicules ferroviaires tels que les véhicules hybrides définis dans l'IEC 62864-1:2016.

General Information

• Status: Published
• Publication Date: 06-Dec-2017
• ICS: 45.060.01 - Railway rolling stock in general
• Technical Committee: TC 9 - Electrical equipment and systems for railways
• Drafting Committee: PT 62928 - TC 9/PT 62928
• Current Stage: PPUB - Publication issued
• Start Date: 07-Dec-2017
• Completion Date: 08-Dec-2017

Overview

IEC 62928:2017 is an international standard developed by the International Electrotechnical Commission (IEC) specifically for railway applications involving rolling stock equipped with onboard lithium-ion traction batteries. This standard provides comprehensive guidelines covering the design, operational parameters, safety protocols, data exchange, testing requirements, and marking/labeling criteria essential for lithium-ion battery systems used as energy storage solutions in railway vehicles, including hybrid traction systems.

The purpose of IEC 62928:2017 is to ensure the reliability, safety, and efficient operation of lithium-ion traction batteries aboard railway vehicles by harmonizing technical requirements and testing methods. It thus plays a vital role in advancing electric traction technology in modern railway rolling stock.

Key Topics

• Design Configuration
  The standard defines various components and configurations of the battery system including battery pack, modules, battery management system (BMS), and battery thermal management system (BTMS). This hierarchical configuration ensures proper integration and functionality within railway vehicles.

• Operational Conditions
  IEC 62928 specifies mechanical, environmental, electrical, and electromagnetic compatibility (EMC) conditions. It details acceptable temperature ranges, vibration and shock resistance, insulation coordination, and software requirements to ensure battery reliability under railway operating conditions.

• Safety Requirements
  Safety is paramount with specific guidelines on fire protection, isolation for maintenance, and safety signage. The standard emphasizes preventive measures and test protocols to minimize hazards associated with lithium-ion batteries.

• Testing Methods
  A wide range of tests including electrical, mechanical, performance, endurance, dielectric, self-discharge, and operational balancing are prescribed. These tests ensure battery system performance, safety, and longevity comply with railway industry demands.

• Marking and Documentation
  The standard mandates proper designation, nameplates, and marking of battery cells, packs, and components. Adequate documentation supports traceability and operational transparency crucial for maintenance and regulatory compliance.

Applications

IEC 62928:2017 applies to lithium-ion traction battery systems used in railway rolling stock such as:

• Energy storage systems (ESS) in hybrid traction vehicles conforming to IEC 62864-1:2016.
• Electric trains and trams requiring onboard energy storage for traction power.
• Battery modules and packs integrated into hybrid propulsion systems for enhanced energy efficiency and reduced emissions.

This standard supports manufacturers, integrators, and operators striving for safe, efficient, and standardized battery solutions in electric railway transport, enabling consistent performance and interoperability across different railway systems.

Related Standards

• IEC 62864-1:2016 - Defines hybrid traction vehicle requirements relevant to battery system integration.
• IEC 62619:2017 - Safety tests for large-format lithium-ion batteries, referenced for safety testing protocols.
• IEC Technical Committees (e.g., TC 9) - Develop additional rolling stock electrical components standards contributing to coherent railway system design.
• Railway-specific EMC and insulation standards - Complement operational requirements outlined in IEC 62928 to ensure electromagnetic compatibility and electrical safety.

---

For manufacturers, operators, and engineers working in railway electrification and rolling stock design, IEC 62928:2017 is an essential standard to implement onboard lithium-ion traction batteries conforming to global safety, performance, and testing requirements, supporting the advancement of sustainable and reliable railway propulsion technologies.

Standards Content (Sample)

IEC 62928 ®
Edition 1.0 2017-12
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Railway applications – Rolling stock – Onboard lithium-ion traction batteries

Applications ferroviaires – Matériel roulant – Batteries d'accumulateurs de
traction embarquées au lithium-ion
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IEC 62928 ®
Edition 1.0 2017-12
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Railway applications – Rolling stock – Onboard lithium-ion traction batteries

Applications ferroviaires – Matériel roulant – Batteries d'accumulateurs de

traction embarquées au lithium-ion

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 45.060.01 ISBN 978-2-8322-5019-8

– 2 – IEC 62928:2017 © IEC 2017
CONTENTS
FOREWORD . 5
INTRODUCTION . 7
1 Scope . 9
2 Normative references . 9
3 Terms, definitions and abbreviated terms . 10
3.1 Terms and definitions. 10
3.2 Abbreviated terms . 17
4 Configuration of battery system . 17
4.1 Battery system . 17
4.2 Battery pack/module . 18
4.3 Battery management system (BMS) . 19
4.4 Battery thermal management system (BTMS) . 20
5 Parameter measurement tolerances . 20
6 Operational conditions . 20
6.1 General . 20
6.2 Mechanical conditions . 21
6.3 Environmental conditions . 21
6.3.1 General . 21
6.3.2 Ambient temperature . 21
6.3.3 Temperature in battery enclosure . 21
6.3.4 Temperature for life time calculation . 21
6.4 Electrical conditions . 21
6.4.1 Traction circuits . 21
6.4.2 Control circuits . 21
6.4.3 Insulation coordination . 22
6.5 Electromagnetic compatibility (EMC) . 22
6.6 Software . 22
7 Designation and marking . 22
7.1 Nameplate . 22
7.2 Designations for cells and battery system . 22
7.3 Marking . 23
7.3.1 General . 23
7.3.2 Battery pack/module and cells . 23
7.3.3 Other components . 23
7.3.4 Additional information . 23
8 Safety requirements . 23
8.1 General safety consideration . 23
8.2 Safety signs . 24
8.2.1 Outside the battery box. 24
8.2.2 Inside the battery box . 24
8.3 Isolation for maintenance or service . 24
8.4 Fire protection . 25
9 Dimensions . 25
10 Electrical requirements . 25
10.1 Operating voltage range of the battery system . 25

10.2 Ripple current . 25
10.3 Charge and discharge control of the battery system . 25
10.4 Communication . 25
10.5 Starting of disabled battery system . 26
10.6 Insulation status. 26
10.7 Battery management system (BMS) . 26
11 Mechanical requirement . 26
11.1 Mechanical integration . 26
11.2 Shock and vibration . 26
11.3 Degree of protection . 27
12 Performance requirement . 27
12.1 Design energy and power calculation methodology . 27
12.1.1 General . 27
12.1.2 Sizing . 27
12.1.3 Documentation . 28
12.2 Cooling / heating requirement . 28
12.3 End of life performance . 28
13 Storage and transportation conditions. 29
13.1 Transportation . 29
13.2 Storage of battery systems . 29
13.3 Self-discharge . 29
14 Tests . 29
14.1 Kind of tests . 29
14.1.1 General . 29
14.1.2 Test categories . 30
14.2 Electrical tests . 31
14.2.1 Electrical characteristics tests . 31
14.2.2 Battery management system (BMS) tests . 32
14.2.3 Performance test . 33
14.2.4 Endurance in cycles . 34
14.2.5 Dielectric test . 37
14.2.6 Self-discharge test . 37
14.2.7 Operational balancing test . 39
14.3 Mechanical tests . 40
14.3.1 Physical appearance . 40
14.3.2 Mass measurement . 40
14.3.3 Shock and vibration test . 40
14.3.4 Test of the degree of protection . 40
14.4 Safety tests . 40
14.4.1 Safety test according to IEC 62619:2017 . 40
14.4.2 Special tests for rolling stock . 41
Annex A (informative) Examples of battery system configuration . 45
Annex B (informative) Examples of parameter ranges for additional high power cycling
tests . 49
Bibliography . 50

Figure 1 – Hierarchy of standards related to IEC 62928 . 8
Figure 2 – Functional block of battery system . 18

– 4 – IEC 62928:2017 © IEC 2017
Figure 3 – Illustration of definitions for cell, cell block and battery pack/module . 19
Figure 4 – Illustration of self-discharge test . 38
Figure A.1 – Example of configuration for contactor inside of the battery box . 45
Figure A.2 – Examples of battery box configurations with the contactor outside battery box . 47
Figure A.3 – Example of configuration of a BTMS outside of battery box . 48
Figure A.4 – Example of configuration of a BMS and a BTMS included in another
system outside of battery box . 48

Table 1 – List of tests . 30
Table B.1 – Examples of parameter ranges for additional high power cycling tests . 49

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
RAILWAY APPLICATIONS – ROLLING STOCK –
ONBOARD LITHIUM-ION TRACTION BATTERIES

FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote
international co-operation on all questions concerning standardization in the electrical and electronic fields. To
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8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of
patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 62928 has been prepared by IEC technical committee 9: Electrical
equipment and systems for railways.
The text of this standard is based on the following documents:
FDIS Report on voting
9/2317/FDIS 9/2329/RVD
Full information on the voting for the approval of this standard can be found in the report on
voting indicated in the above table.
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.

– 6 – IEC 62928:2017 © IEC 2017
The committee has decided that the contents of this publication will remain unchanged until
the stability date indicated on the IEC web site under "http://webstore.iec.ch" in the data
related to the specific publication. At this date, the publication will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
INTRODUCTION
In the 90s the market started developing mainly portable lithium technology batteries. Existing
standards for lithium-ion batteries currently focus on small portable batteries:
• IEC 61960-3:2017, 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.
These above mentioned documents do not cover large cells and batteries for industrial and
railway applications, which are non-portable and weigh hundreds of kilograms.
TC 21 and SC 21A decided to start work on large capacity lithium cells and batteries:
• IEC 62619:2017, Secondary cells and batteries containing alkaline or other non-acid
electrolytes – Safety requirements for secondary lithium cells and batteries for use in
industrial applications,
• IEC 62620:2014, Secondary cells and batteries containing alkaline or other non-acid
electrolytes – Secondary lithium cells and batteries for use in industrial applications.
The documents are often generic and mention railway applications only as an example.
Therefore, this document is developed for specifying the requirements for railway traction
applications.
In addition, TC 9 has developed the following document:
• IEC 62864-1:2016, Railway applications – Rolling stock – Power supply with onboard
energy storage system – Part 1: Series hybrid system
IEC 62864-1:2016 specifies the general requirements for the onboard energy storage system
as a system level. The hierarchy of standards is shown in Figure 1 of IEC 62864-1:2016.
It is part of a series of standards, referring to each other. The hierarchy of the standards used
in the railway specific area related to IEC 62928 is as follows:

– 8 – IEC 62928:2017 © IEC 2017
Overview of the technical framework
IEC 61133
- Level 1: vehicle/system interface
Railway applications – Rolling stock – Testing of
rolling stock on completion of construction and
before entry into service
IEC 62864-1
Railway applications – Rolling stock – Power
supply with onboard energy storage system –
Part 1: Series hybrid system
IEC 61377
Railway applications – Rolling stock – Combined
- Level 2: System and interfaces
test method for traction systems
- Level 3: Components
IEC 61287-1 IEC 60349 (all parts)
Railway applications – Power converters
Electrical traction – Rotating electrical machines
installed on board rolling stock – for rail and road vehicles
Part 1: Characteristics and test methods
- Level 4: Subcomponents
IEC 61881-3
IEC 62928
Railway applications – Rolling stock equipment –
Railway applications – Rolling stock equipment –
Capacitors for power electronics –
Onboard lithium-ion traction batteries
Part 3: Electric double-layer capacitors

IEC
Figure 1 – Hierarchy of standards related to IEC 62928
The standards listed in Figure 1 are not exhaustive.

RAILWAY APPLICATIONS – ROLLING STOCK –
ONBOARD LITHIUM-ION TRACTION BATTERIES

1 Scope
This document applies to onboard lithium-ion traction batteries for railway applications.
This document specifies the design, operation parameters, safety recommendations, data
exchange, routine and type tests, as well as marking and designation.
Battery systems described in this document are used for the energy storage system (ESS) for
the traction power of railway vehicles such as hybrid vehicles as defined in IEC 62864-1:2016.
Auxiliary batteries to supply power only to the auxiliary equipment are excluded.
Subcomponents within the battery systems, e.g. battery management system (BMS) and
battery thermal management system (BTMS), are also covered in this document.
Power conversion equipment (e.g. chopper, converter, etc.), inductors, capacitors and
switchgear are excluded from the scope of this document.
General requirements for onboard ESS are described in IEC 62864-1:2016.
This document specifies the lithium-ion battery technology but does not prevent the use of
battery technologies other than lithium-ion technology for application as traction batteries.
A hybrid energy storage system, which uses two or more energy storage technologies
combined, e.g. a traction battery and double layer capacitors, is not covered in this document.
However, if different technologies of energy storage systems are used on the same railway
vehicle and managed independently, each independent energy storage system is covered by
its own document.
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 – Part 482: Primary and
secondary cells and batteries
IEC 60050-811:2017, International Electrotechnical Vocabulary – Chapter 811: Electric
traction
IEC 60051 (all parts), Direct acting indicating analogue electrical measuring instruments and
their accessories
IEC 60077-1, Railway applications – Electric equipment for rolling stock – Part 1: General
service conditions and general rules
IEC 60077-5, Railway applications – Electric equipment for rolling stock – Part 5:
Electrotechnical components – Rules for HV fuses

– 10 – IEC 62928:2017 © IEC 2017
IEC 60529, Degrees of protection provided by enclosures (IP Code)
IEC 60571, Railway applications – Electronic equipment used on rolling stock
IEC 60850, Railway applications – Supply voltages of traction systems
IEC 61373, Railway applications – Rolling stock equipment – Shock and vibration tests
IEC 61991, Railway applications – Rolling stock – Protective provisions against electrical
hazards
IEC 62236-3-2, Railway applications – Electromagnetic compatibility – Part 3-2: Rolling stock
– Apparatus
IEC 62278:2002, Railway applications – Specification and demonstration of reliability,
availability, maintainability and safety (RAMS)
IEC 62279, Railway applications – Communications, signalling and processing systems –
Software for railway control and protection systems
IEC 62497-1, Railway application – Insulation coordination – Part 1: Basic requirements –
Clearances and creepage distances for all electrical and electronic equipment
IEC 62498-1:2010, Railway applications – Environmental conditions for equipment – Part 1:
Equipment on board rolling stock
IEC 62619:2017, Secondary cells and batteries containing alkaline or other non-acid
electrolytes – Safety requirements secondary lithium cells and batteries for use in industrial
applications
IEC 62620:2014, Secondary cells and batteries containing alkaline or other non-acid
electrolytes – Secondary lithium cells and batteries for use in industrial applications
IEC 62864-1:2016, Railway applications – Rolling stock – Power supply with onboard energy
storage system – Part 1: Series hybrid system
ISO/IEC Guide 51: 2014, Safety aspects – Guidelines for their inclusion in standards
ISO 7010, Graphical symbols – Safety colours and safety signs – Registered safety signs
3 Terms, definitions and abbreviated terms
3.1 Terms and definitions
For the purposes of this document, the terms and definitions given in IEC 60050-482,
IEC 60050-811 and ISO/IEC Guide 51, as well as the following apply.
ISO and IEC maintain terminological databases for use in standardization at the following
addresses:
• IEC Electropedia: available at http://www.electropedia.org/
• ISO Online browsing platform: available at http://www.iso.org/obp

3.1.1
charge retention
capacity retention
ability of battery system to retain capacity on open circuit under specified conditions
Note 1 to entry: See also self-discharge.
[SOURCE: IEC 60050-482:2004, 482-03-35, modified – “a cell or battery” has been changed
to “battery system”]
3.1.2
self-discharge
phenomenon by which a cell or battery system loses energy in other ways than by discharge
into an external circuit
Note 1 to entry: See also charge retention.
[SOURCE: IEC 60050-482:2004, 482-03-27, modified – “battery” has been changed to
“battery system”.]
3.1.3
final voltage
end-of-discharge voltage
specified closed circuit voltage at which a discharge of a cell or battery system is terminated
[SOURCE: IEC 62620:2014, 3.3 modified – “battery” has been changed to “battery system”.]
3.1.4
nominal voltage
suitable approximate value of voltage used to designate or identify the voltage of a cell or
battery system
Note 1 to entry: The cell and/ or battery system manufacturer may provide the nominal voltage.
Note 2 to entry: The nominal voltage of a battery system of n series connected cells is equal to n times the
nominal voltage of a single cell.
[SOURCE: IEC 62620:2014, 3.4, modified – “identify a cell” has been changed to ”identify
the voltage of a cell” and “battery” is changed to “battery system”.]
3.1.5
rated capacity
capacity value of a cell or battery system determined under specified conditions and declared
by the manufacturer
Note 1 to entry: The rated capacity is the quantity of electricity C Ah (ampere-hours) declared by the
n
manufacturer which a single cell or battery can deliver during a n h period when charging, storing and discharging
under the conditions specified in 6.3.1 of IEC 62620:2014. n is 5 for an E, M and H discharge rate type cell or
battery.
[SOURCE: IEC 60050-482:2004, 482-03-15, modified – “battery” has been changed to
“battery system” and Note 1 to entry has been added.]
3.1.6
state of charge
SOC
remaining capacity to be discharged, normally expressed as a percentage of full capacity by
selected expression as defined in Annex A of IEC 62864-1:2016

– 12 – IEC 62928:2017 © IEC 2017
[SOURCE: IEC 62864-1:2016, 3.1.13, modified – “as expressed in relevant standards” has
been changed to ”by selected expression as defined in Annex A of IEC 62864-1:2016” and
Note 1 to entry has been deleted.]
3.1.7
cell
secondary lithium cell
secondary cell where electrical energy is derived from the insertion/extraction reactions of
lithium-ions or oxidation/reduction reaction of lithium between the negative electrode and the
positive electrode
Note 1 to entry: The cell typically has an electrolyte that consists of a lithium salt and organic solvent compound
in liquid, gel or solid form and has a metal or a laminate film casing. It is not ready for use in an application
because it is not yet fitted with its final housing, terminal arrangement and electronic control device.
[SOURCE: IEC 62620:2014, 3.6]
3.1.8
cell block
group of cells connected together in parallel configuration with or without protective devices
(e.g. fuse or PTC) and monitoring circuitry
Note 1 to entry: It is not ready for use in an application because it is not yet fitted with its final housing, terminal
arrangement and electronic control device.
[SOURCE: IEC 62620:2014, 3.7]
3.1.9
battery pack/module
energy storage device, which is comprised of one or more cells electrically connected
Note 1 to entry: In this document a module is same as a battery pack.
Note 2 to entry: It incorporates a protective housing and be provided with terminals or other interconnection
arrangement.
Note 3 to entry: It includes at least monitoring circuitry, which provides information (e.g. cell voltage,
temperature) to a battery system.
Note 4 to entry: It may include a protective device and control circuitry.
[SOURCE: IEC 62620:2014, 3.9, modified – “/module” has been added in the term and ”or
module” has been deleted in the definition. Note 1 to entry has been divided into Note 2 to
entry to Note 4 to entry and Note 1 to entry has been added.]
3.1.10
battery branch
group of battery packs/modules connected together either in a series and/or parallel
configuration, which has the voltage equal to that of the battery system and is the smallest
electrically isolatable subsystem
Note 1 to entry: Electrical isolation is done by means of disconnecting devices, e.g. contactors, switchgears,
circuit breakers, etc.
Note 2 to entry: A battery branch may be contained in a single enclosure or multiple enclosures.
3.1.11
battery system
system which incorporates one or more cells, modules or battery packs including battery
management system and thermal management system as well as disconnecting and/ or
isolating devices, e.g. contactors, disconnectors, fuses, etc.

Note 1 to entry: Refer to Figure 2, Figure 3 and Figure A.1 to Figure A.4.
[SOURCE: IEC 62620:2014, 3.10, modified – Definition after “battery packs” has been
changed. Note 1 to entry has been replaced.]
3.1.12
hybrid vehicle
vehicle that can store energy in an onboard ESS and is driven by using the stored energy as
well as electric power from a generator or overhead lines
[SOURCE: IEC 62864-1:2016, 3.1.14]
3.1.13
safety
freedom from risk which is not tolerable
[SOURCE: ISO/IEC Guide 51:2014, 3.14]
3.1.14
hazard
potential source of harm
[SOURCE: IEC 60050-903:2013, 903-01-02, modified – Note 1 to entry, Note 2 to entry and
Note 3 to entry have been deleted.]
3.1.15
intended use
use in accordance with information provided with a product or system, or, in the absence of
such information, by generally understood patterns of usage
Note 1 to entry: Intended use can include load profile agreed between the integrator and the battery system
manufacturer.
[SOURCE: ISO/IEC Guide 51:2014, 3.6, modified – Note 1 to entry has been added.]
3.1.16
leakage
visible escape of liquid electrolyte
[SOURCE: IEC 62619:2017, 3.13]
3.1.17
venting
release of excessive internal pressure from a cell, module, battery pack, or battery system in
a manner intended by design to preclude rupture or explosion
[SOURCE: IEC 62619:2017, 3.14]
3.1.18
rupture
mechanical failure of a cell container or battery case induced by an internal or external cause,
resulting in exposure or spillage but not ejection of materials
[SOURCE: IEC 62619:2017, 3.15]

– 14 – IEC 62928:2017 © IEC 2017
3.1.19
explosion
failure that occurs when a cell container or battery case opens violently and solid components
are forcibly expelled
Note 1 to entry: Releasing liquid, gas, and/ or smoke is not explosion.
[SOURCE: IEC 62619:2017, 3.16, modified – Note 1 to entry has been modified.]
3.1.20
fire
emission of flames from a cell, battery pack/module or battery system
[SOURCE: IEC 62619:2017, 3.17, modified – “module, battery pack,” has been changed to
“battery pack/module”.]
3.1.21
upper limit charging voltage of cell
highest charging voltage in the cell operating region from a safety stand point specified by the
cell manufacturer
[SOURCE: IEC 62619:2017, 3.19, modified – “from a safety stand point” has been added
before “by the cell”.]
3.1.22
maximum voltage of the battery system
highest voltage of the battery system in which the maximum voltage of any individual cell is
below the upper limit charging voltage of cell as defined in 3.1.21 and any components
operate in its specified/ permissible operating range under all operating conditions
3.1.23
lower limit discharging voltage of cell
lowest discharging voltage in the cell operating region from a safety stand point specified by
the cell manufacturer
[SOURCE: IEC 62619:2017, 3.22, modified – “in the cell … stand point” has been added.]
3.1.24
minimum voltage of battery system
lowest voltage of the battery system in which the minimum voltage of any individual cell is
above the lower limit discharging voltage of cell as defined in 3.1.23 and any components
operate in its specified/ permissible operating range under all operating conditions
3.1.25
maximum charging current
highest current for charging in the cell operating region from a safety stand point specified by
the cell manufacturer
[SOURCE: IEC 62619:2017, 3.20, modified – “maximum” has been replaced with “highest”,
“which is” has been changed to “from a safety stand point”.]
3.1.26
maximum discharging current
highest current for discharging in the cell operating region from a safety stand point specified
by the cell manufacturer
3.1.27
energy storage system
ESS
physical system which consists of one or more ESUs and the other equipment required to
connect to the DC link such as converters, control and monitoring systems, inductors,
protection devices, cooling systems, etc.
[SOURCE: IEC 62864-1:2016, 3.1.22]
3.1.28
energy storage unit
ESU
physical equipment which is comprised of an energy storage technology, especially lithium-
ion traction battery system in the context of this document
Note 1 to entry: Balancing the traction power among ESUs is a function of the upper system level.
[SOURCE: IEC 62864-1:2016, 3.1.20, modified – “technology” is specified to “lithium-ion
traction battery system”, “standard” has been replaced with “document” and Note 1 to entry
has been changed.]
3.1.29
battery management system
BMS
system associated with a battery pack which monitors and/or manages its state, disconnects
or isolates the battery pack, calculates secondary data, communicates data outside of the
battery system and/or controls its environment to influence the battery’s safety, performance
and/or service life
Note 1 to entry: The function of the BMS can be assigned to the battery pack or to equipment that uses the
battery pack.
Note 2 to entry: Its functions include thermal control.
[SOURCE: IEC 62620:2014, 3.11, modified – “electronic” has been deleted, “disconnect or
isolate the battery pack,” has been added, “reports that data” has been replaced with
“communicates data outside of the battery system” and “and has the functions to cut …” has
been deleted. Note 2 to entry has been replaced.]
3.1.30
battery thermal management system
BTMS
system associated with a battery pack which monitors and/or manages its thermal behaviour
in order to maintain the temperature of the battery pack in the intended range for load profile
agreed between the integrator and the battery system manufacturers
3.1.31
user
organization which operates the traction system including ESS
Note 1 to entry: The user is normally an organization which operates the vehicle equipped with the traction
system, unless the responsibility is delegated to a main contractor or consultant.
[SOURCE: IEC 61377:2016, 3.4, modified – “(see Figure 3)” has been deleted and “including
ESS” has been added.]
3.1.32
integrator
organization which has the technical responsibility of the complete traction system including
ESS
– 16 – IEC 62928:2017 © IEC 2017
Note 1 to entry: The integrator can be the user or the train builder or the manufacturer of a traction system, or
none of them.
3.1.33
manufacturer
organization which has the technical responsibility for its scope of supply
Note 1 to entry: The manufacturer can be the train builder or the system integrator of a traction system, a cell
manufacturer, etc. If necessary to explicitly distinguish, “traction system manufacturer”, “battery system
manufacturer” or “cell manufacturer” is expressed.
3.1.34
operational pattern
definition by the user and/or the manufacturers in order to fulfil the needs of operations
including auxiliaries, e.g. duty cycle, auxiliary loads, safety margin of energy content,
degraded mode, etc.
Note 1 to entry: For the purposes of this document, operational pattern is considered at the vehicle level.
[SOURCE: IEC 62864-1:2016, 3.1.19 modified – Note 1 to entry has been added.]
3.1.35
load profile
electric power against time of occurrence to illustrate the variance in a load during a given
time interval
Note 1 to entry: For the purposes of this document, the load profile is defined at the terminals of the battery
system.
[SOURCE: IEC 60050-617:2009, 617-04-05 modified – “curve representing supplied” has
been deleted. Note 1 to entry has been added. ]
3.1.36
end of life
EOL
point at which the battery system cannot fulfil the required functionality or operational pattern
as initially agreed among the user/ the integrator and the manufacturers
Note 1 to entry: The internal resistance or capacity may be used as a parameter of the end of life.
[SOURCE: IEC 62864-1:2016, 3.1.15, modified – “the user” has been replaced with “the
user/ the integrator”. Note 1 to ent
...