IEC 62933-5-2:2020

Electrical energy storage (EES) systems - Part 5-2: Safety requirements for grid-integrated EES systems - Electrochemical-based systems

IEC 62933-5-2:2020 primarily describes safety aspects for people and, where appropriate, safety matters related to the surroundings and living beings for grid-connected energy storage systems where an electrochemical storage subsystem is used.

Systèmes de stockage de l'énergie électrique (EES) - Partie 5-2: Exigences de sécurité pour les systèmes EES intégrés dans un réseau - Systèmes électrochimiques

L’IEC 62933-5-2:2020 décrit principalement les aspects liés à la sécurité des personnes et, le cas échéant, les questions de sécurité associées à l’environnement et aux êtres vivants pour les systèmes de stockage de l’énergie raccordés à un réseau qui utilisent un sous-système électrochimique de stockage.

General Information

• Status: Published
• Publication Date: 15-Apr-2020
• ICS: 01 - GENERALITIES. TERMINOLOGY. STANDARDIZATION. DOCUMENTATION
• ICS: 13.020.30 - Environmental impact assessment
• ICS: 31.080.01 - Semiconductor devices in general
• Technical Committee: TC 120 - Electrical Energy Storage (EES) systems
• Drafting Committee: WG 5 - TC 120/WG 5
• Current Stage: PPUB - Publication issued
• Start Date: 08-May-2020
• Completion Date: 16-Apr-2020

Standards Content (Sample)

IEC 62933-5-2
®

Edition 1.0 2020-04
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside


Electrical energy storage (EES) systems –
Part 5-2: Safety requirements for grid-integrated EES systems –
Electrochemical-based systems

Systèmes de stockage de l'énergie électrique (EES) –
Partie 5-2: Exigences de sécurité pour les systèmes EES intégrés dans un
réseau – Systèmes électrochimiques

IEC 62933-5-2:2020-04(en-fr)

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IEC 62933-5-2

®


Edition 1.0 2020-04




INTERNATIONAL



STANDARD




NORME



INTERNATIONALE
colour

inside










Electrical energy storage (EES) systems –

Part 5-2: Safety requirements for grid-integrated EES systems –

Electrochemical-based systems




Systèmes de stockage de l'énergie électrique (EES) –

Partie 5-2: Exigences de sécurité pour les systèmes EES intégrés dans un


réseau – Systèmes électrochimiques













INTERNATIONAL

ELECTROTECHNICAL

COMMISSION


COMMISSION

ELECTROTECHNIQUE


INTERNATIONALE




ICS 13.020.30 ISBN 978-2-8322-8146-8




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® Registered trademark of the International Electrotechnical Commission
Marque déposée de la Commission Electrotechnique Internationale

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– 2 – IEC 62933-5-2:2020 © IEC 2020
CONTENTS
FOREWORD . 5
INTRODUCTION . 7
1 Scope . 8
2 Normative references . 8
3 Terms and definitions . 9
4 Basic guidelines for safety of BESS . 11
4.1 General . 11
4.2 Approach to BESS safety . 12
4.3 BESS changes in ownership, control or use . 14
5 Hazard considerations . 14
6 BESS system risk assessment . 15
6.1 BESS structure . 15
6.1.1 General characteristics . 15
6.1.2 Specific characteristics . 16
6.2 Description of BESS conditions . 16
6.3 Risk analysis . 16
6.3.1 General . 16
6.3.2 Hazard identification specific to BESS . 17
6.3.3 Risk consideration . 17
6.3.4 System level risk analysis . 17
6.4 System level risk assessment . 17
7 Requirements necessary to reduce risks . 17
7.1 General measures to reduce risks . 17
7.2 Preventive measures against damage to neighbouring inhabitants . 18
7.3 Preventive measures against physical injury or damage to the health of
workers and residents . 18
7.4 Overcurrent protection design . 18
7.5 BESS disconnection and shutdown . 18
7.6 Operation and maintenance . 18
7.7 Staff training . 18
7.8 Safety design . 19
7.9 General requirements for BESS safety . 19
7.10 Inherently safe design of BESS . 19
7.10.1 Protection from electrical hazards . 19
7.10.2 Protection from mechanical hazards . 20
7.10.3 Protection from explosion . 21
7.10.4 Protection from hazards arising from electric, magnetic, and
electromagnetic fields . 21
7.10.5 Protection from fire hazards . 21
7.10.6 Protection from temperature hazards . 21
7.10.7 Protection from chemical effects . 22
7.10.8 Protection from hazards arising from auxiliary, control and
communication system malfunctions . 22
7.10.9 Protection from hazards arising from environments. 22
7.11 Guards and protective measures. 23
7.11.1 General . 23
7.11.2 BESS disconnection and shutdown . 23

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IEC 62933-5-2:2020 © IEC 2020 – 3 –
7.11.3 Other guards and protective functions of BESS . 24
7.12 Information for end users . 28
7.13 Life cycle safety management . 28
7.13.1 Operation and maintenance . 28
7.13.2 Partial system change . 31
7.13.3 Design revision . 32
7.13.4 End of service life management . 33
7.13.5 Measures for validating life cycle safety management . 33
8 System validation and testing . 33
8.1 General . 33
8.2 Validation and testing of BESS . 36
8.2.1 Electrical hazards . 36
8.2.2 Mechanical hazards . 38
8.2.3 Explosion . 38
8.2.4 Hazards arising from electric, magnetic, and electromagnetic fields . 39
8.2.5 Fire hazards (propagation) . 39
8.2.6 Temperature hazards. 40
8.2.7 Chemical effects . 41
8.2.8 Hazards arising from auxiliary, control and communication system
malfunctions . 42
8.2.9 Hazards arising from environments . 42
8.2.10 IP rating of BESS enclosure and protective guards . 43
9 Guidelines and manuals . 43
Annex A (informative) Ownership models of BESS . 44
Annex B (informative) BESS hazards and risks . 45
B.1 General introduction . 45
B.2 Hazard concerns . 51
B.2.1 General . 51
B.2.2 Fire hazards . 51
B.2.3 Chemical hazards . 51
B.2.4 Electrical hazards . 51
B.2.5 Energy hazards . 52
B.2.6 Physical hazards . 52
B.2.7 High-pressure hazards . 52
B.3 Hazard considerations under normal operating conditions . 52
B.3.1 Fire and explosive hazards . 52
B.3.2 Chemical hazards . 52
B.3.3 Electrical hazards . 53
B.3.4 Physical hazards . 53
B.4 Hazard considerations under emergency/abnormal conditions . 54
B.4.1 Fire hazards . 54
B.4.2 Chemical hazards . 54
B.4.3 Electrical hazards . 55
B.4.4 Physical hazards . 56
B.5 Commercially available battery technologies . 56
B.5.1 Lithium ion (Li-ion) batteries (C-A) . 56
B.5.2 Lead-acid batteries (C-B) . 57
B.5.3 Nickel batteries (C-B) . 58
B.5.4 High-temperature sodium batteries (C-C). 60

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B.5.5 Flow batteries (C-D) . 61
B.5.6 Lithium metal solid state batteries (C-Z) . 63
B.6 Other technologies . 63
Annex C (informative) Large-scale fire testing on BESS . 64
Annex D (informative) Test methods for protection from hazards arising from
environments . 65
D.1 General . 65
D.2 Outdoor installations subject to moisture exposure . 65
D.3 Outdoor installation near marine environments . 65
Annex E (informative)  Information for validation of BESS life cycle safety
management . 66
E.1 Overview . 66
E.2 General introduction . 66
E.3 Operation and maintenance process . 66
E.4 Preventive maintenance . 66
E.5 Measuring and monitoring of system soundness . 67
E.6 Staff training . 67
E.7 Partial system change . 67
E.8 Design revision . 67
Annex F (informative) BESS safety signage . 68
Annex G (informative) Example of testing for verification of thermal control operation . 69
Bibliography . 70

Figure 1 – General description for risk assessment and reduction of BESS . 11
Figure 2 – An example of BESS architecture. 15
Figure 3 – Example of isolated condition (whole isolation of BESS) . 24
Figure 4 – Incompatibility of capacity and/or usage in a BESS . 32

Table 1 – BESS categories . 13
Table 2 – Examples of BESS use. 14
Table 3 – Examples of components within subsystems of a BESS . 16
Table 4 – Examples of incompatibilities that can arise from system changes . 32
Table 5 – Overview of validation and testing for BESS . 35
Table B.1 – Hazards of BESS in common . 47
Table B.2 – Hazards of BESS using non-aqueous electrolyte battery (category "C-A") . 48
Table B.3 – Hazards of BESS using aqueous electrolyte battery (category "C-B") . 49
Table B.4 – Hazards of BESS using high temperature battery (category "C-C") . 50
Table B.5 – Hazards of BESS using flow battery (category "C-D") . 51

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IEC 62933-5-2:2020 © IEC 2020 – 5 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________

ELECTRICAL ENERGY STORAGE (EES) SYSTEMS –

Part 5-2: Safety requirements for grid-integrated EES systems –
Electrochemical-based systems

FOREWORD
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rights. IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 62933-5-2 has been prepared by IEC technical committee 120:
Electrical Energy Storage (EES) Systems.
This International Standard is to be used in conjunction with IEC TS 62933-5-1:2017.
The text of this International Standard is based on the following documents:
FDIS Report on voting
120/173/FDIS 120/182/RVD

Full information on the voting for the approval of this International Standard can be found in the
report on voting indicated in the above table.
This document has been drafted in accordance with the ISO/IEC Directives, Part 2.

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– 6 – IEC 62933-5-2:2020 © IEC 2020
A list of all parts in the IEC 62933 series, published under the general title Electrical energy
storage (EES) systems, can be found on the IEC website.
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under "http://webstore.iec.ch" in the data related to
the specific document. At this date, the document will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.

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IEC 62933-5-2:2020 © IEC 2020 – 7 –
INTRODUCTION
All the electrical energy storage systems (EESS) follow the general safety requirements as
described in IEC TS 62933-5-1, which is based on a systems approach. IEC 62933-5-2 follows
the same structure as IEC TS 62933-5-1 and provides additional requirements for battery
energy storage systems (BESS). The additional requirements are provided for the following
reasons:
a) BESS can be integrated into a significant range of electrical grids.
b) The level of safety requirements awareness can vary between utilities, system integrators,
operators and end-users.
c) Although the safety of individual subsystems is generally covered by international standards
at ISO and IEC levels, the safety matters that arise due to the combination of
electrochemical accumulation subsystems and any electrical subsystems are not always
considered. BESS are complex at the systems level due to the variety of potential battery
options and configurations, including the combination of subsystems (e.g. control systems
for electrochemical accumulation subsystems, electrochemical accumulation subsystems,
power conversion subsystems and auxiliary subsystems). Compliance with standards and
related material produced specifically for the safety of subsystems cannot be sufficient to
reach an acceptable level of safety for the overall system.
d) BESS can have additional safety hazards, due, for example, to the presence of chemicals,
the emission of toxic gases, chemicals spilt around the electrochemical accumulation
subsystems and to events critical for safety from electrochemical accumulation subsystems
that cause safety issues for the entire BESS. They can cause loss of power at any part of
the systems and buildings that can result in additional threats to safety. From a systems
perspective, these individual hazards can have a system wide impact.

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– 8 – IEC 62933-5-2:2020 © IEC 2020
ELECTRICAL ENERGY STORAGE (EES) SYSTEMS –

Part 5-2: Safety requirements for grid-integrated EES systems –
Electrochemical-based systems



1 Scope
This part of IEC 62933 primarily describes safety aspects for people and, where appropriate,
safety matters related to the surroundings and living beings for grid-connected energy storage
systems where an electrochemical storage subsystem is used.
This safety standard is applicable to the entire life cycle of BESS (from design to end of service
life management).
This document provides further safety provisions that arise due to the use of an electrochemical
storage subsystem (e.g. battery system) in energy storage systems that are beyond the general
safety considerations described in IEC TS 62933-5-1.
This document specifies the safety requirements of an “electrochemical” energy storage system
as a "system" to reduce the risk of harm or damage caused by the hazards of an electrochemical
energy storage system due to interactions between the subsystems as presently understood.
2 Normative references
The following documents are referred to in the text in such a way that some or all of the
...