IEC TR 62933-3-200:2025

Electrical energy storage (EES) systems – Part 3-200: Planning and performance assessment of electrical energy storage systems<em> – </em>Design principles of electrochemical based EES systems

IEC TR 62933-3-200:2025 presents an overview and design cases of electrochemical based EES systems in power generation side, transmission and distribution side, and customer side. Furthermore, design principles for electrochemical based EES systems such as sizing and selection of subsystem, integration scheme, site and layout, and system safety measures are provided. Furthermore, design principles for electrochemical based EES systems such as sizing and selection of subsystem, integration scheme, site and layout, and system safety measures are provided.

General Information

• Status: Published
• Publication Date: 20-May-2025
• ICS: 13.020.30 - Environmental impact assessment
• Technical Committee: TC 120 - Electrical Energy Storage (EES) systems
• Drafting Committee: WG 3 - TC 120/WG 3
• Current Stage: PPUB - Publication issued
• Start Date: 21-May-2025
• Completion Date: 20-Dec-2024

Overview

IEC TR 62933-3-200:2025 - Technical Report: Electrical energy storage (EES) systems – Part 3-200: Planning and performance assessment of electrical energy storage systems – Design principles of electrochemical based EES systems - provides a comprehensive, application-oriented guide to planning and designing electrochemical energy storage for power generation, transmission & distribution, and customer-side installations. Published by IEC in 2025, this TR combines conceptual overview, subsystem descriptions and multiple real-world design cases to support performance assessment and system engineering.

Key topics and technical requirements

The report focuses on practical design principles for electrochemical based EES systems, covering:

• System overview and architecture
  • Application functions, typical system structures and functions of subsystems.
• Subsystem design
  • Accumulation subsystem (battery chemistry and sizing approaches)
  • Power conversion subsystem (PCS) topology and integration
  • Auxiliary, control, protection, communication and management subsystems
• Sizing and selection
  • Battery sizing and selection guidance for different applications and chemistries
• Integration schemes
  • Primary and auxiliary point-of-connection (POC) schemes for grid integration
• Site & layout
  • Site selection, layout best practices and single-line/plant layout considerations
• System safety measures
  • Fire detection and suppression, lightning protection, earthing and safety architectures
• Performance and operation
  • Planning and performance assessment guidance, EMS/BMS communication and operation modes
• Illustrative design cases
  • Detailed cases such as 30 MW/15 MWh LFP, 15 MW/60 MWh flow battery (FB), 50 MW/300 MWh NAS, and multiple transmission/distribution and customer-side examples that demonstrate integration and layout choices

Practical applications and users

Who benefits from IEC TR 62933-3-200:2025:

• Grid planners, utilities and transmission/distribution engineers
• EES system designers and integrators (EPCs)
• Renewable project developers combining storage with generation (PV, wind)
• Battery manufacturers, PCS vendors and BMS/EMS developers
• Safety, permitting and regulatory authorities evaluating siting and fire protection
• Asset owners performing performance assessment and lifecycle planning

This TR is practical for project-level planning, procurement specifications, and early-stage engineering where electrochemical storage design choices (chemistry, sizing, PCS topology, POC, safety systems) materially affect performance and cost.

Related standards

• Part of the IEC TR 62933 series on electrical energy storage systems - consult other parts of IEC 62933 for complementary guidance and normative standards related to testing, safety and interoperability.

Keywords: IEC TR 62933-3-200:2025, electrical energy storage (EES) systems, electrochemical based EES, design principles, battery sizing, power conversion subsystem, BMS, EMS, site and layout, system safety, grid integration, POC, performance assessment.

Standards Content (Sample)

IEC TR 62933-3-200 ®
Edition 1.0 2025-05
TECHNICAL
REPORT
Electrical energy storage (EES) systems –
Part 3-200: Planning and performance assessment of electrical energy storage
systems – Design principles of electrochemical based EES systems
ICS 13.020.30  ISBN 978-2-8327-0100-3

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– 2 – IEC TR 62933-3-200:2025 © IEC 2025
CONTENTS
FOREWORD . 8
1 Scope . 10
2 Normative references . 10
3 Terms, definitions and abbreviated terms . 10
3.1 Terms and definitions . 10
3.2 Abbreviated terms . 11
4 Overview of electrochemical based EES systems . 12
4.1 General . 12
4.2 Application functions . 12
4.3 System structure . 13
4.4 Functions of subsystems . 13
4.4.1 General . 13
4.4.2 Accumulation subsystem . 13
4.4.3 Power conversion subsystem (PCS) . 14
4.4.4 Auxiliary subsystem . 14
4.4.5 Control subsystem . 14
5 Design cases of electrochemical based EES systems in power generation side . 15
5.1 Case 1: 30 MW/15 MWh LFP EESS . 15
5.1.1 General information . 15
5.1.2 Integration scheme . 15
5.1.3 Site and layout. 17
5.1.4 Design of subsystems . 18
5.2 Case 2: 15 MW/60 MWh FB EESS . 23
5.2.1 General information . 23
5.2.2 Integration scheme . 24
5.2.3 Site and layout. 25
5.2.4 Design of subsystems . 26
5.3 Case 3: 50 MW/300 MWh NAS EESS . 29
5.3.1 General information . 29
5.3.2 Integration scheme . 29
5.3.3 Site and layout. 31
5.3.4 Design of subsystems . 32
5.4 Case 4: 100 MW/400 MWh FB EESS . 35
5.4.1 General information . 35
5.4.2 Integration scheme . 36
5.4.3 Site and layout. 38
5.4.4 Design of subsystems . 38
6 Design cases of electrochemical based EES systems in transmission and
distribution side . 42
6.1 Case 5: 99,8 MW/99,8 MWh LFP/NCM EESS. 42
6.1.1 General information . 42
6.1.2 Integration scheme . 43
6.1.3 Site and layout. 43
6.1.4 Design of subsystems . 45
6.2 Case 6: 7,2 MW/8,6 MWh hybrid EESS . 48
6.2.1 General information . 48
6.2.2 Integration scheme . 49

6.2.3 Site and layout. 50
6.2.4 Design of subsystems . 51
6.3 Case 7: 100 MW/200 MWh LFP EESS . 53
6.3.1 General information . 53
6.3.2 Integration scheme . 54
6.3.3 Site and layout. 54
6.3.4 Design of subsystems . 56
6.4 Case 8: 70 MW/140 MWh LFP EESS . 58
6.4.1 General information . 58
6.4.2 Integration scheme . 59
6.4.3 Site and layout. 59
6.4.4 Design of subsystems . 60
6.5 Case 9: 12 MW/37 MWh NCM EESS . 64
6.5.1 General information . 64
6.5.2 Integration scheme . 65
6.5.3 Site and layout. 67
6.5.4 Design of subsystems . 69
7 Design cases of electrochemical based EES systems in customer side . 77
7.1 Case 10: 1 MW/1 MWh Li-ion EESS with PV in a performance verified
project . 77
7.1.1 General information . 77
7.1.2 Integration scheme . 77
7.1.3 Site and layout. 78
7.1.4 Design of subsystems . 78
7.2 Case 11: 1 MW/3 MWh LC EESS in PV-storage-charging building . 82
7.2.1 General information . 82
7.2.2 Integration scheme . 83
7.2.3 Site and layout. 83
7.2.4 Design of subsystems . 85
7.3 Case 12: 1 MW × 7 h/3 MW × 13,5 s NAS EESS in standby power system. 88
7.3.1 General information . 88
7.3.2 Integration scheme . 89
7.3.3 Site and layout. 90
7.3.4 Design of subsystems . 90
8 Design considerations for electrochemical based EES systems . 92
8.1 Application functions . 92
8.1.1 Application functions in typical scenarios . 92
8.1.2 Priority of application functions in typical scenarios . 92
8.2 Sizing and selection of battery . 93
8.2.1 Battery sizing . 93
8.2.2 Battery selection . 93
8.3 Integration scheme . 95
8.3.1 Primary POC scheme . 95
8.3.2 Auxiliary POC scheme . 95
8.4 Site and layout . 96
8.4.1 Site . 96
8.4.2 Layout . 96
8.5 Subsystem scheme . 97
8.5.1 Accumulation subsystem . 97

– 4 – IEC TR 62933-3-200:2025 © IEC 2025
8.5.2 Power conversion subsystem . 97
8.5.3 Auxiliary subsystem . 101
8.5.4 Protection subsystem . 102
8.5.5 Communication subsystem . 103
8.5.6 Management subsystem . 103
8.6 System safety measures . 104
8.6.1 Fire detection and suppression . 104
8.6.2 Lightning protection . 104
8.6.3 Earthing of accumulation subsystem . 105
Annex A (informative) Basic information on electrochemical based EESS cases . 106
Annex B (informative) Primary POC of electrochemical based EESS to the grid . 107
B.1 General . 107
B.2 Primary POC of electrochemical based EESS in power generation side . 107
B.3 Primary POC of electrochemical based EESS in transmission and
distribution side . 107
B.4 Primary POC of electrochemical based EESS in customer side . 108
Annex C (informative) Typical electrochemical based EESS information model . 109
C.1 Logical devices (LD) and Logical nodes (LN) for electrochemical based
EESS . 109
C.2 Data objects for electrochemical based EESS . 109
Bibliography . 112

Figure 1 – Typical architecture of electrochemical based EES system . 13
Figure 2 – Aerial view of Case 1 . 15
Figure 3 – Integration scheme of Case 1 . 16
Figure 4 – Single line diagram of phase A, B and C container . 16
Figure 5 – Single line diagram of EES system . 17
Figure 6 – Layout of Case 1 . 17
Figure 7 – PCS topology . 19
Figure 8 – Architecture of the EMS network . 21
Figure 9 – Actual operation curve recorded by EMS system . 23
Figure 10 – View of Case 2 . 24
Figure 11 – Integration scheme of Case 2 . 25
Figure 12 – Layout of Case 2 . 26
Figure 13 – Performance of active power output . 28
Figure 14 – Aerial view of Case 3 . 29
Figure 15 – Integration scheme of Case 3 . 30
Figure 16 – Single line diagram of EESS unit . 31
Figure 17 – Layout of Case 3 . 32
Figure 18 – Operating modes for the EES system . 35
Figure 19 – Aerial view of Case 4 . 36
Figure 20 – Integration scheme of Case 4 . 37
Figure 21 – Single line diagram of EESS unit . 38
Figure 22 – BMS communication architecture . 40
Figure 23 – Aerial view of Case 5 . 42
Figure 24 – Integration scheme of Case 5 . 43

Figure 25 – Layout of Case 5 . 44
Figure 26 – Front view of transformer and PCS . 44
Figure 27 – The architecture of communication subsystem . 47
Figure 28 – Actual operation curve recorded of typical unit . 48
Figure 29 – Aerial view of Case 6 . 49
Figure 30 – Integration scheme of Case 6 . 50
Figure 31 – Internal layout of containers . 50
Figure 32 – Communication architecture of LTO EESS . 52
Figure 33 – Aerial view of Case 7 . 53
Figure 34 – Integration scheme of Case 7 . 54
Figure 35 – Layout of Case 7 . 55
Figure 36 – Aerial view of Case 8 . 59
Figure 37 – Layout of Case 8 . 60
Figure 38 – Aerial view of Case 9 . 64
Figure 39 – Integration scheme of Case 9 . 65
Figure 40 – BESS interconnection scheme . 66
Figure 41 – View inside the container, power conversion room (left) and battery room
(right) . 67
Figure 42 – Layout of Case 9 . 68
Figure 43 – Congestion management by two levels of intelligent automation using
BESS . 74
Figure 44 – Multi-service test, congestion management in priority against frequency
regulation . 75
Figure 45 – Circuit diagram of the BESS black start test . 75
Figure 46 – Test 1:BESS soft start-up energization . 76
Figure 47 – Test 2: connecting to windfarm, and test 3: grid coupling and switch to grid
following mode . 76
Figure 48 – Integration scheme of Case 10 . 77
Figure 49 – Layout of Case 10 . 78
Figure 50 – The architecture of control and communication subsystem . 80
Figure 51 – The power and SOC of BESS following the AGC signals . 81
Figure 52 – Measured P-Q capability of the PV-BESS plant . 81
Figure 53 – The bus voltages and active power of the PV plant in black start of the PV

plant with BESS . 82
Figure 54 – Integration scheme of Case 11 . 83
Figure 55 – Layout of the accumulation subsystem in Case 11 . 84
Figure 56 – Layout scheme of the PCS in Case 11 . 85
Figure 57 – View of Case 12 . 88
Figure 58 – Integration scheme of Case 12 . 90
Figure 59 – Layout of Case 12 . 90
Figure 60 – Topology of single-stage conversion . 98
Figure 61 – Topology of single-stage conversion with expansion . 98
Figure 62 – Topology of two-stage conversion . 99
Figure 63 – Topology of two-stage conversion with DC-common connection . 99
Figure 64 – Topology of two-stage conversion with AC-common connection . 100

– 6 – IEC TR 62933-3-200:2025 © IEC 2025
Figure 65 – Cascaded topology . 100
Figure B.1 – Typical primary POC of electrochemical based EESS in power
generation side . 107
Figure B.2 – Typical primary POC of electrochemical based EESS in transmission and
distribution side . 108
Figure B.3 – Typical primary POC of electrochemical based EESS in customer side . 108
Figure C.1 – Overview: Logical Devices (LD) and Logical Nodes (LN) for
electrochemical based EESS . 109

Table 1 – Application functions of electrochemical based EESS in typical scenarios . 12
Table 2 – Parameters of LFP battery cell . 18
Table 3 – Parameters of battery pack . 18
Table 4 – Parameters of battery cluster . 18
Table 5 – Parameters of 5MW PCS . 19
Table 6 – Parameters of FB EESS . 27
Table 7 – Main Parameters of PCS . 27
Table 8 – Verified control modes . 28
Table 9 – Parameters of NAS battery cell . 33
Table 10 – Parameters of battery module . 33
Table 11 – Parameters of battery container. 33
Table 12 – Main technical parameters of PCS . 34
Table 13 – Parameters of flow battery . 39
Table 14 – Parameters of NCM battery cell . 45
Table 15 – Parameters of LFP battery cell . 45
Table 16 – Parameters of the PCS and transformer . 46
Table 17 – Parameters of LTO module . 51
Table 18 – Parameters of the PCS and transformer . 51
Table 19 – Main electrical parameters of LFP battery cell . 56
Table 20 – Main electrical parameters of battery module . 56
Table 21 – Main electrical parameters of battery container . 56
Table 22 – Main electrical parameters of the PCS . 57
Table 23 – Air-cooled accumulation subsystem parameters . 61
Table 24 – Liquid-cooled accumulation subsystem parameters . 61
Table 25 – Air-cooled PCS technical parameters . 61
Table 26 – Liquid-cooled PCS technical parameters . 62
Table 27 – Fire detector types of fire detection and alarm system . 64
Table 28 – Parameters of BESS. 70
Table 29 – Parameters of PCS and transformer . 71
Table 30 – Parameters of HV/MV transformer . 72
Table 31 – Main technical parameters of the PCS . 79
Table 32 – Protection configuration of the PCS . 79
Table 33 – Main technical parameters of the lead-carbon battery . 86
Table 34 – Main technical parameters of the PCS . 86
Table 35 – EES system specification . 89

Table 36 – Main parameters of PCS . 91
Table 37 – Performances and parameters of energy storage batteries . 94
Table 38 – Typical primary POC voltage level for electrochemical based EESS . 95
Table 39 – Typical auxiliary POC scheme for electrochemical based EESS . 96
Table 40 – Comparison of PCS topology . 101
Table 41 – Typical auxiliary power supply scheme . 102
Table 42 – Examples of fire detection sensors for each type of battery . 104
Table 43 – Examples of fire extinguishing agents for each type of battery . 104
Table A.1 – Basic information on electrochemical based EESS cases . 106
Table C.1 – Example of information of management system for accumulation
subsystem . 110
Table C.2 – Example of information of management system for power conversion
subsystem . 111

– 8 – IEC TR 62933-3-200:2025 © IEC 2025
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
ELECTRICAL ENERGY STORAGE (EES) SYSTEMS –

Part 3-200: Planning and performance assessment
of electrical energy storage systems – Design principles
of electrochemical based EES systems

FOREWORD
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IEC TR 62933-3-200 has been prepared by IEC technical committee TC 120: Electrical Energy
Storage (EES) Systems. It is a Technical Report.
The text of this Technical Report is based on the following documents:
Draft Report on voting
120/381/DTR 120/399/RVDTR
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 Technical Report 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/publications.
A list of all parts in the IEC 62833 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 webstore.iec.ch in the data related to the
specific document. At this date, the document will be
• reconfirmed,
• withdrawn, or
• revised.
IMPORTANT – The "colour inside" logo on the cover page of this document indicates
that it contains colours which are considered to be useful for the correct understanding
of its contents. Users should therefore print this document using a colour printer.

– 10 – IEC TR 62933-3-200:2025 © IEC 2025
ELECTRICAL ENERGY STORAGE (EES) SYSTEMS –

Part 3-200: Planning and performance assessment
of electrical energy storage systems – Design principles
of electrochemical based EES systems

1 Scope
This part of IEC 62933, which is a Technical Report, presents an overview and design cases of
electrochemical based EES systems in power generation side, transmission and distribution
side, and customer side. Furthermore, design principles for electrochemical based EES
systems such as sizing and selection of subsystem, integration scheme, site and layout, and
system safety measures are provided.
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 62933-1:2024, Electrical energy storage (EES) systems – Part 1: Vocabulary
IEC TS 62933-3-2:2023, Electrical energy storage (EES) systems – Part 3-2: Planning and
performance assessment of electrical energy storage systems – Additional requirements for
power intensive and renewable energy sources integration related applications
IEC TS 62933-3-3, Electrical energy storage (EES) systems – Part 3-3: Planning and
performance assessment of electrical energy storage systems – Additional requirements for
energy intensive and backup power applications
3 Terms, definitions and abbreviated terms
3.1 Terms and definitions
For the purposes of this document, the terms and definitions given in IEC 62933-1, IEC TS
62933-3-2 and IEC TS 62933-3-3 and the following apply.
ISO and IEC maintain terminological databases for use in standardization at the following
addresses:
• IEC Electropedia: available at https://www.electropedia.org/
• ISO Online browsing platform: available at https://www.iso.org/obp
3.1.1
cascaded PCS
power conversion system or subsystem (PCS) consisting of the same submodules in a cascade
connection which perform electrical energy accumulation and AC/DC conversion
Note 1 to entry: The PCS commonly consists of three-phase arms with star or delta connection. Each phase arm
consists of an inductor and a certain number of submodules in series.
Note 2 to entry: Half-bridge or full-bridge topology is commonly adopted in single submodule.

3.1.2
peak shifting
reduction of the power consumption from the power grid by providing the power exceeding the
limit value from other active power sources
3.2 Abbreviated terms
AGC automatic generation control
AVC automatic voltage control
BAMS battery array management system
BCMU battery cluster management unit
BESS battery energy storage system
BMS battery management system
BMU battery management unit
CGI controllable grid interface
DCS distributed control system
DER distributed energy resource
EES electrical energy storage
EESS electrical energy storage system
EMS energy management system
FB flow battery
FFR fast frequency response
FSS fire suppression system
HV high voltage
LA lead acid
LC lead carbon
LFP lithium iron phosphate
LTO lithium titanium oxide
NAS sodium sulfur
NCA nickel cobalt aluminum
NCM nickel cobalt manganese
PCS power conversion subsystem / power conversion system
PH potential of hydrogen
POC point of connection
POD power oscillation damping
PV photovoltaic
RTU remote terminal unit
SCADA supervisory control and data acquisition
SOC state of charge
SOE state of energy
SPS standby power system
TSO transmission system operator
UPS uninterrupted power supply
V2G vehicle to grid
VCB vacuum circuit-breaker
VOC volatile organic compounds

– 12 – IEC TR 62933-3-200:2025 © IEC 2025
4 Overview of electrochemical based EES systems
4.1 General
Electrochemical based EES systems are designed to provide different functions in various
application scenarios. Therefore, it is important to specify the structure of electrochemical
based EES systems and the functions of each subsystem.
Twelve design cases of electrochemical based EES systems in power generation side,
transmission and distribution side and customer side are shown in Clause 5 to Clause 7 as
examples to illustrate the structure and functions of electrochemical based EES systems. Brief
information on 12 cases is included in Annex A.
4.2 Application functions
The application functions of electrochemical based EES systems differ according to their
purposes and locations, which form typical scenarios. The application functions of
electrochemical based EES systems in typical scenarios are shown in Table 1. In power
generation side with traditional thermal power units, EESS can provide frequency regulation,
peak shaving, black start, etc. EESS can offer output power smoothing, output power firming
and peak shifting in the typical scenario of renewable energy sources integration such as wind
or solar power generation. In transmission and distribution side, EESS can perform functions
of frequency regulation, peak shaving, reactive voltage support and backup power supply, etc.
In customer side, EESS can provide various application functions such as voltage sag mitigation,
peak shifting, backup power supply, etc. In microgrid with DER side, EESS can offer additional
functions of output power smoothing, output power firming, power oscillation damping and black
start compared to the customer side.
Table 1 – Application functions of electrochemical based EESS in typical scenarios
Typical scenarios
Renewable Power Transmission
Application functions
Customer Microgrid
energy sources generation and distribution
side with DER
integration side side
Frequency regulation     
Reactive voltage support     
Voltage sag mitigation   
Output power smoothing   
 
Output power firming
Power oscillation
   
damping
Peak shaving   
Peak shifting   
 
Black start
Backup power supply    
NOTE 1 Table 1 is based on IEC TS 62933-3-2:2023.
NOTE 2 The contents of frequency regulation, output power smoothing or output power firming, voltage sag
mitigation, power oscillation damping and reactive voltage support are specified in IEC TS 62933-3-2:2023.
NOTE 3 The contents of peak shaving or peak shifting and backup power supply are specified in IEC 62933-2-1.
TM
NOTE 4 The content of black start is specified in IEEE Std 2030.2.1 .

Normally, an electrochemical based EES system can perform more than one application
function in practical projects. For example, the application functions of both frequency
regulation and black start can be provided by an electrochemical based EES system.
4.3 System structure
The typical architecture of an electrochemical based EES system is shown in Figure 1.

NOTE 1 IEC 62933-1:2024, Figure 6, is used with revision on accumulation subsystem.
NOTE 2 The auxiliary subsystem connection shown here represents a typical connection, but there are other ways
to feed the auxiliary subsystem as discussed in 8.3.2.
Figure 1 – Typical architecture of electrochemical based EES system
An electrochemical based EES system includes the accumulation subsystem, the power
conversion subsystem, the auxiliary subsystem and the control subsystem. The boundary
between the electrochemica
...