IEC TR 63650:2026

IEC TR 63650 ®
Edition 1.0 2026-06
TECHNICAL
REPORT
Electrochemical capacitor for use in electrical energy storage

ICS 31.060.99  ISBN 978-2-8327-1257-3

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CONTENTS
FOREWORD . 4
1 Scope . 6
2 Normative references . 6
3 Terms, definitions and abbreviated terms . 6
3.1 Terms and definitions . 6
3.2 Abbreviated terms. 7
4 Overview of electrochemical capacitor . 8
4.1 Classification and characteristics of electrochemical capacitor . 8
4.1.1 Classification of electrochemical capacitor . 8
4.1.2 Technical characteristics of electrochemical capacitor . 9
4.2 Development of global electrochemical capacitor market . 9
5 Application of electrochemical capacitor in EES . 10
5.1 General . 10
5.2 Generation side storage . 11
5.2.1 Support the smooth integration of renewable energy into the grid . 11
5.2.2 Coordinate with traditional power generation units for frequency
regulation . 11
5.2.3 Back-up source . 11
5.3 Grid side storage . 12
5.3.1 Substation frequency regulation . 12
5.3.2 Microgrid power support . 12
5.3.3 Distribution terminal back-up power supply . 12
5.4 User side storage . 13
5.5 Typical structure of electrochemical capacitor EES system . 13
6 Testing items of electrochemical capacitor for use in EES . 14
6.1 Testing items of electrochemical capacitor cells for use in EES . 14
6.2 Testing items of electrochemical capacitor modules for use in EES . 14
7 Standardization demand and roadmap for electrochemical capacitor used in EES . 16
7.1 Necessity of developing standards for electrochemical capacitors used in
EES . 16
7.2 Current status of ISO/IEC standards related to electrochemical capacitor . 17
7.2.1 General. 17
7.2.2 Technical procedures for electrochemical capacitor . 17
7.2.3 Testing procedures for electrochemical capacitor . 18
7.2.4 Summary . 19
7.3 Roadmap of electrochemical capacitor standardization for use in EES . 19
7.3.1 Conception of electrochemical capacitor standard structure for use in
EES . 19
7.3.2 The development path of future standards . 20
Annex A (informative) Application case of electrochemical capacitor EES system
coupled with thermal power unit to participate in power frequency regulation . 21
A.1 General . 21
A.2 Introduction of electrochemical capacitor EES system . 21
A.2.1 Technical principle . 21
A.2.2 Composition of electrochemical capacitor EES system . 22
A.2.3 Electrical diagram of energy storage system . 22
A.3 Characteristics of electrochemical capacitor in the project . 23
A.3.1 Charging-discharging characteristic curve, self-discharging
characteristic curve . 23
A.3.2 Cycle life characteristic curve . 25
A.3.3 Energy density measurement . 25
A.3.4 Power density measurement . 26
A.3.5 Safety test . 26
A.4 Application achievement . 27
Annex B (informative) Application case of electrochemical capacitor EES system in
island distributed microgrid . 30
B.1 General . 30
B.2 Introduction of electrochemical capacitor EES system . 30
B.3 Characteristics of electrochemical capacitor in the project . 32
B.3.1 Discharging characteristics curve of 2,7 V, 3 000 F electrochemical
capacitor cells . 32
B.3.2 Discharging characteristics curve of 48 V, 165 F electrochemical
capacitor modules . 32
B.3.3 Charging and discharging characteristics curve of 500 kW×15 s
electrochemical capacitor EES system . 33
B.4 Application achievement . 34
Annex C (informative) Application case of electrochemical capacitor EES system in
brake energy recovery . 35
C.1 General . 35
C.2 Technical principle . 35
C.3 Application achievement . 36
Annex D (informative) Application case of electrochemical capacitor EES system in
back-up source of wind power system . 37
D.1 General . 37
D.2 Technical principle . 37
D.3 Application achievement . 38
Bibliography . 39

Figure 1 – Classification of electrochemical capacitors . 8
Figure 2 – Application of CESS in thermal power plant . 11
Figure 3 – Application of CESS in substation . 12
Figure 4 – Schematic diagram of household light storage system . 13
Figure 5 – Schematic diagram of CESS . 13
Figure 6 – Link between CESS and users' needs . 16
Figure A.1 – CESS project of thermal power plant . 21
Figure A.2 – Technical principle of CESS coupled with thermal power unit to participate
in power frequency regulation . 22
Figure A.3 – Structure diagram of electrochemical capacitor bank . 22
Figure A.4 – Electrical diagram of CESS . 23
Figure A.5 – Typical charging-discharging characteristics curve of 4 V/15 000 F hybrid
electrochemical capacitor . 24
Figure A.6 – Typical self-discharging characteristics curve of 4 V/15 000 F hybrid
electrochemical capacitor . 25
Figure A.7 – Cycle life characteristic curve of 4 V/15 000 F hybrid electrochemical
capacitor . 25
Figure A.8 – Safety test of 4 V/15 000 F hybrid electrochemical capacitor . 27
Figure A.9 – Schematic diagram of frequency regulation performance improvement
after CESS investment . 28
Figure A.10 – Temperature difference between banks . 29
Figure B.1 – CESS project of island distributed microgrid . 30
Figure B.2 – 500 kW × 15 s CESS schematic . 31
Figure B.3 – Structure diagram of CESS . 32
Figure B.4 – Discharging curve of 2,7 V, 3 000 F EDLC cells . 32
Figure B.5 – Discharging curve of 48 V, 165 F EDLC modules . 33
Figure B.6 – Discharging curve of branch 1 in 500 kW × 15 s CESS . 33
Figure B.7 – Charging curve of branch 1 in 500 kW × 15 s CESS . 34
Figure C.1 – Schematic diagram of CESS braking energy recovery system . 35
Figure D.1 – Topology diagram of wind turbine pitch control system with
electrochemical capacitor energy storage as back-up source . 38

Table 1 – Parameters of EDLCs and hybrid electrochemical capacitors . 9
Table 2 – Testing items of electrochemical capacitor cells . 14
Table 3 – Testing items of electrochemical capacitor modules . 15
Table 4 – Electrochemical capacitor standard structure . 19
Table 5 – Standard system of electrochemical capacitors for use in EES. 20
Table A.1 – Energy density measurement results of 4 V/15 000 F hybrid
electrochemical capacitor . 26
Table A.2 – Power density measurement results of 4 V/15 000 F hybrid
electrochemical capacitor . 26
Table A.3 – Energy conversion efficiency test of CESS . 28
Table A.4 – Energy conversion efficiency test of LIB EES system . 28

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
Electrochemical capacitor for use in electrical energy storage

FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for
standardization comprising all national electrotechnical committees (IEC National Committees).
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IEC 63650 has been prepared by IEC technical committee 40: Capacitors and resistors for
electronic equipment. It is a Technical Report.
The text of this Technical Report is based on the following documents:
Draft Report on voting
40/3294/DTR 40/3312/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.
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.
1 Scope
This technical report investigates the primary technological approaches, current applications,
and development prospects of electrochemical capacitors (supercapacitors). In particular, this
document also analyses the technical solutions and characteristics of electrochemical capacitor
applications in the field of Electrical Energy Storage (EES) and provides representative
application cases. Then, the testing items of the electrochemical capacitors for use in EES are
introduced for the cells and modules, respectively.
By collecting the existing standards of electrochemical capacitor , this document identifies the
gap between the existing IEC and ISO standards and the actual needs of electrochemical
capacitors used in EES and proposes descriptions and a roadmap for future standardization of
electrochemical capacitors in the field of EES. This work will promote the rapid progress and
broader applications of electrochemical capacitors in the field of EES.
2 Normative references
There are no normative references in this document.
3 Terms, definitions and abbreviated terms
3.1 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminology 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
electrochemical capacitor
supercapacitor
device that stores electrical energy using a double layer in an electrochemical cell
Note 1 to entry: An electrochemical capacitor, at least one electrode primarily stores energy through a double-layer
capacitance formed at the electrode and electrolyte interface. The relationship curve between time and voltage during
constant current charging or discharging is usually approximately linear.
Note 2 to entry: The electrochemical capacitor is not to be confused with electrolytic capacitors (IEC 60050-
114:2014 [1], 114-03-04).
[SOURCE: IEC 60050-114:2014 [1], 114-03-03, modified — Note 1 to entry has been added.]
3.1.2
electric double-layer capacitor
device that stores electrical energy using a double layer in an electrochemical cell, and whose
positive and negative electrodes are of the same material
Note 1 to entry: The electrolytic capacitor is not included in capacitor of this document.
[SOURCE: IEC 62576:2018 [2], 3.13]
3.1.3
hybrid electrochemical capacitor
capacitor that uses an electric double-layer on one electrode and a Faradaic reaction on the
other to store electrical energy
Note 1 to entry: A faradaic reaction is an electrochemical reaction involving the transfer of electrons including redox
reaction and doping and undoping reaction.
3.1.4
energy efficiency
ratio of discharging energy to charging energy of an electrochemical capacitor under specified
test conditions and test methods, expressed as a percentage
3.1.5
retention rate of energy
ratio (%) of charging energy and discharging energy to its initial charging energy and initial
discharging energy of an electrochemical capacitor respectively, under specified test conditions
and test methods
3.1.6
recovery rate of energy
ratio (%) of the charging energy and discharging energy to the initial charging energy and initial
discharging energy after storage or open-circuit standing of an electrochemical capacitor,
respectively, under specified test conditions and test methods
3.1.7
range
measure of variability in statistical data, which is the difference between the maximum and
minimum values, i.e., the numerical result obtained by subtracting the minimum value from the
maximum value
3.1.8
fire
continuous combustion lasting more than 1 s that occurs in any part of the electrochemical
capacitor
Note 1 to entry: Sparks and arcs are not considered combustion.
3.1.9
explosion
rupture of the electrochemical capacitor casing with a loud noise and is accompanied by the
ejection of solid materials, including its main components (excluding the normal opening of
safety valves)
3.1.10
leakage
unplanned escape of electrolyte, gas or other material from a cell or electrochemical capacitor
3.2 Abbreviated terms
For the purposes of this document, the following abbreviated terms apply.
AGC Automatic generation control
CESS Capacitor energy storage system
CMS Capacitor management system
DOD Depth of discharge
EDLC Electric double-layer capacitor
EES Electrical energy storage
EMS Energy management system
LIB Lithium-ion battery
LIC Lithium-ion capacitor
PCS Power conversion system
SIC Sodium-ion capacitor
SOC State of charge
4 Overview of electrochemical capacitor
4.1 Classification and characteristics of electrochemical capacitor
4.1.1 Classification of electrochemical capacitor
Electrochemical capacitor is an electrochemical energy storage capacitor, at least one
electrode primarily stores energy through a double-layer capacitance formed at the electrode
and electrolyte interface. The relationship curve between time and voltage during constant
current charging or discharging is usually approximately linear.
According to energy storage mechanisms, electrochemical capacitors can be categorized as
EDLCs and hybrid electrochemical capacitor, as shown in Figure 1.
EDLCs store electrical energy using a double layer in an electrochemical cell, and whose
positive and negative electrodes are of the same material. EDLCs are primarily composed of
carbon materials such as activated carbon, graphene, and carbon nanotubes as electrode
materials, without Faraday reaction, and are widely used in wind turbine pitch control system,
transportation, energy recovery, consumer electronics and power fluctuation suppression, etc.
Hybrid electrochemical capacitors use an electric double-layer on one electrode and a Faradaic
reaction on the other to store electrical energy. Hybrid electrochemical capacitors primarily
include LICs and SICs, among which LICs have been widely used in large-capacity energy
storage scenarios such as rail transit, primary power frequency regulation, secondary power
frequency regulation, etc.
Figure 1 – Classification of electrochemical capacitors
4.1.2 Technical characteristics of electrochemical capacitor
Compared to conventional secondary batteries, the technical characteristics of electrochemical
capacitor have the following advantages.
a) High power density. Electrochemical capacitors enable rapid energy storage and release,
with power outputs of up to 10 kW/kg or more, because the energy storage process in
electrochemical capacitors occurs at the surface of the electrode material and is less
constrained by the rate of ion diffusion.
b) Fast charging and discharging speed. Electrochemical capacitors can usually be charged
and discharged to more than 95 % of their rated capacity in 10 s to 10 min, due to the
charging and discharging process of electrochemical capacitors is basically a surface
electrochemical process.
c) Long cycle life. EDLCs have excellent reversibility of charging and discharging because they
5 6
do not involve Faradaic reactions, and their cycle life can reach 5 × 10 times to 1 × 10
5 6
times. Hybrid electrochemical capacitors can also have a cycle life of 5 × 10 to 1 × 10
times.
d) Large working voltage range. The operating voltage of the electrochemical capacitors can
be arbitrarily changed within its rated voltage range.
e) Wide operating temperature range. Electrochemical capacitors can be used normally at
ambient temperatures of −40 °C to 70 °C, and have excellent low temperature
characteristics, which can achieve low maintenance by reducing the number of auxiliary
devices such as temperature control equipment.
The main technical parameters of EDLCs and hybrid electrochemical capacitors are shown in
Table 1.
Table 1 – Parameters of EDLCs and hybrid electrochemical capacitors
Parameters EDLC Hybrid electrochemical capacitor
Energy density 1,5 Wh/kg to 8 Wh/kg 20 Wh/kg to 80 Wh/kg
Power density 5 kW/kg to 50 kW/kg 5 kW/kg to 50 kW/kg
Temperature range -40 °C to +70 °C -40 °C to +70 °C
5 6 6
Charging and discharging cycles
5 × 10 to 1 × 10 5 × 10⁵ to 1 × 10
Lifetime >10 years
＞10 years
4.2 Development of global electrochemical capacitor market
In recent years, the global electrochemical capacitor market has shown rapid growth. According
to incomplete statistics from the Supercapacitor Industry Alliance, the global electrochemical
capacitor market size (taking components as the statistical object) was USD 1,38 ×10 in 2020.
In 2021, the global electrochemical capacitor market size (measured by components) reached
USD 1,59 ×10 , representing a year-on-year growth of 15,2 %. The increasing demand in
sectors such as wind power generation, consumer electronics, EES and industrial applications
is the main driver of the growth in the electrochemical capacitor market.
Electrochemical capacitors are widely used in various fields such as new energy, grid
equipment, transportation, consumer electronics, and industry, etc. In 2021, the highest market
share for electrochemical capacitors was in the new energy sector, accounting for
approximately 35,2 %. Transportation and industrial markets followed with shares of 18,8 %
and 14,6 %, respectively. Grid equipment and consumer electronics also had significant market
shares at 10,5 % and 8,5 %, respectively. The combined share of other application areas was
13,4 %.
Undoubtedly, the strong demand for component products will drive significant growth across
the entire industry chain, including electrode materials, electrolytes, separators, current
collectors, auxiliary materials, various manufacturing equipment and control systems, analysis
and testing instruments, safety equipment, system integration, and power management and
other technology development and basic research, as well as software, patents, analysis,
testing, and standardization, industry analysis, investment services and other technical service
system.
In addition, with the continuous deepening of the transformation of green and low-carbon
energy, the proportion of renewable energy connected to the grid is constantly increasing, and
the demand for the regulating of power quality is growing day by day. Electrochemical
capacitors, as short-term high-power energy storage devices, are very suitable for power grid
frequency regulation. In 2021, the sales of electrochemical capacitors in the power field began
to grow more than 5 times. However, the current application of megawatt-level electrochemical
capacitor systems applied in the power industry, such as independent energy storage frequency
regulation project, grid-forming energy storage project, still have a competitive disadvantage in
terms of cost compared to other high-power energy storage technologies. The industry still
needs to make continuous efforts in technology, market, and other aspects.
5 Application of electrochemical capacitor in EES
5.1 General
Electrochemical capacitors have become an indispensable energy storage technology in EES
due to their outstanding electrical characteristics, ultra-long cycling life, good environmental
adaptability, and high levels of safety and stability compared to conventional secondary
batteries.
According to differentiation of energy storage time, EDLCs primarily undertake power
compensation tasks in the range of seconds to 5 min, which is mainly used in the application of
backup power, primary frequency regulation and instantaneous power fluctuation suppression,
etc. The hybrid electrochemical capacitor mainly undertake power compensation tasks in the
range of 5 min to 15 min, which is mainly used in primary and secondary frequency regulation
and other applications.
According to the operation form, the electrochemical CESS includes two types: coupling form
and independent form. The independent form mainly refers to the independent energy storage
power station used for power frequency regulation or power quality improvement or refers to
the independent back-up power supply (such as wind turbine pitch control system, etc.) used
to improve the power supply reliability of important equipment. The coupling form mainly refers
to the CESS to assist the power coordination of the generator unit to achieve power frequency
regulation or power quality improvement.
On the generation side, electrochemical capacitors are mainly used to cooperate with traditional
energy sources, participate in power frequency regulation and smooth the fluctuation of
renewable energy output. On the grid side, electrochemical capacitors are used for power
compensation, thereby enhancing grid reliability. On the user side, the electrochemical
capacitors can be used as back-up source to provide emergency power supply and reduce the
cost of electricity consumption.

5.2 Generation side storage
5.2.1 Support the smooth integration of renewable energy into the grid
To improve inertia response in photovoltaic and wind power grid connection, electrochemical
capacitors can be used as short-time energy storage devices to smooth power fluctuations
caused by wind and solar energy. Taking the wind power system with electrochemical
capacitors as an example, the electrochemical capacitors are connected in parallel to the DC
bus. When the power is greater than the specified output power, the electrochemical capacitors
are charged. When the power is less than the specified power, the power difference is
supplemented by the energy storage device, and the electrochemical capacitors are
discharged. Electrochemical capacitors can provide additional virtual inertia for photovoltaic
and wind turbines, allowing them to smoothly output and connect to the grid, reducing the impact
of the randomness, intermittency, and volatility of renewable energy generation.
5.2.2 Coordinate with traditional power generation units for frequency regulation
The traditional method of power frequency regulation aims at adjusting the power of the
generator unit according to the demands of the power system to maintain the stability of the
system frequency. However, due to the large thermal inertia of the generator set, the power
regulation often faces problems such as slow frequency regulation speed, lag in response to
frequency fluctuations and grid dispatch instructions, and poor regulation accuracy, which
cannot meet the requirements of the power frequency regulation. The CESS can quickly and
accurately control power output and have superior frequency regulation performance. By adding
CESS to traditional thermal power units, thermal power units and energy storage capacitors are
respectively the basic units and the rapid supplementary units in response to the frequency
regulation instructions, utilizing the ability of the energy storage capacitor to quickly regulate
the output power to achieve the purpose of improving the frequency regulation response speed
and accuracy of the units. At present, the global large-scale CESS demonstration applications
are mainly based on the frequency regulation of traditional thermal generating units (as shown
in Figure 2), to ensure the safety, reliability, environmental friendliness, economy and
sustainability of power supply in the future power grid of high proportion renewable energy
generation. The typical application case is shown in Annex A.

Figure 2 – Application of CESS in thermal power plant
5.2.3 Back-up source
CESS is an ideal choice for back-up source of important equipment. Among them, the most
widely used case is the back-up source for wind turbine pitch control system, which plays a
crucial role in the safety of wind turbine operation. The typical application case is shown in
Annex D.
5.3 Grid side storage
5.3.1 Substation frequency regulation
The application of electrochemical capacitor energy storage in substations can shorten the lag
time of primary frequency regulation to ms level, eliminate excessive harmonic currents of the
grid, compensate for temporary voltage dips in the power grid, fundamentally suppress voltage
flicker, and significantly improve power quality and supply reliability. Taking the CESS put into
operation at a 110 kV power station as an example (Figure 3), the system mainly consists of
electrochemical capacitor modules, power electronic converters, and fast power controller. The
fast power controller can complete frequency detection within 10 ms, and the power electronic
converter can realize the fast and accurate support of active power within 2 ms. If there is a
frequency drop caused by large fluctuations in the power grid, the CESS can enter a frequency
regulation mode within 12 ms. At the same time, the qualification rate of the power supply
voltage of the substation maintains at 100 %, and the harmonic content is reduced by 15,6 %.

Figure 3 – Application of CESS in substation
5.3.2 Microgrid power support
In the distributed microgrid dominated by renewable energy, the power fluctuations caused by
the intermittency of solar and wind power generation seriously affect the stability of power
supply and power quality. The CESS can quickly compensate for the active and reactive power
required by the system, smooth power fluctuations quickly, achieve energy balance and stable
control, support reliable operation and smooth switching in grid connected or islanded modes,
and improve the power quality of the distributed microgrid. The typical application case is shown
in Annex B.
5.3.3 Distribution terminal back-up power supply
Electrochemical capacitors used as distribution terminal back-up power supply can improve the
self-healing reliability of the power grid and reduce maintenance costs. The back-up power
supply for distribution automation terminals has changed from lithium-ion batteries to
electrochemical capacitors. The high-power density, long lifespan, and maintenance-free of
electrochemical capacitors can improve the self-healing reliability of the distribution automation
terminal and reduced maintenance costs. When power line failure occurs, electrochemical
capacitors can provide uninterrupted power supply for distribution automation terminals and
switchgears, so that the distribution terminals can still work for a period in the event of line
failure, to save time for a series of operations such as fault detection, protection tripping,
reclosing self-healing, and status reporting to the main station. In this way, the fault zone can
be isolated, and the power supply can be restored in the non-fault zone, to minimize the fault
power outage area.
5.4 User side storage
The main groups of CESS on the user side are industrial and commercial enterprises and
household users. Generally, the energy storage capacity of industrial and commercial
enterprises is in the range of hundreds of kilowatt hours to megawatt hours, and the energy
storage capacity of household users is in the range of hundreds of kilwatt hours to megawatt
hours. A typical application case is brake energy recovery. See Annex C. The CESS is
connected to the user side for off-peak power consumption and power cost reduction, as shown
in Figure 4, and can reduce the peak of electricity consumption and improve electricity stability.
It can also be used as a back-up power source for the grid, providing emergency power supply.
CESS of user side is an important component of integration of generation-grid-load-storage.

Figure 4 – Schematic diagram of household light storage system
5.5 Typical structure of electrochemical capacitor EES system
The CESS mainly includes the electrochemical capacitor bank, the energy storage PCS and
the distribution unit, as shown in Figure 5. Among them, the electrochemical capacitor bank is
the key component of the electrical energy storage system, which is composed of the
electrochemical capacitor modules through the series and parallel form, and the
electrochemical capacitor modules are composed of the electrochemical capacitor cells through
the series and parallel form. The electrochemical capacitor bank converts direct current to
alternating current through the energy storage PCS and then connects to the generator or the
power grid after passing through the distribution unit. In addition, the energy storage system
also includes CMS, EMS, cooling system, fire protection system and other auxiliary systems.

Figure 5 – Schematic diagram of CESS
Obviously, the electrochemical capacitor cells and modules are the basic elements of the CESS,
and their working performance directly determines whether the energy storage system can meet
the users' demands.
6 Testing items of electrochemical capacitor for use in EES
6.1 Testing items of electrochemical capacitor cells for use in EES
The testing items of electrochemical capacitor cells for use in EES projects are shown in Table 2.
Table 2 – Testing items of electrochemical capacitor cells
No. Testing category Testing items Testing or checking parameters
1 Appearance Observe for deformation, cracks, bur, dirt, label, etc.
Basic
2 Dimensions and mass Dimensions, mass.
Characteristics
3 Polarity Terminal polarity mark.
4 Initial charging and Initial charging energy, initial discharging energy,
discharging performance energy efficiency, range.
5 Rate charging and Charging energy, discharging energy, charging time,
discharging performance discharging time, energy efficiency.
6 High temperature charging Charging energy, discharging energy, charging time,
Charging and
and discharging discharging time, energy efficiency.
discharging
performance
characteristics
7 Low temperature Charging Charging energy, discharging energy, charging time,
and Discharging discharging time, energy efficiency.
Performance
Energy retention and
8 Retention rate of energy, recovery rate of energy.
resilience
9 Cycle Cycle performance Record charging energy, discharging energy,
performance charging time, discharging time at the end of the
cycle. Draw a graph of the retention rate of charging
energy, the retention rate of discharging energy and
energy efficiency with the number of cycles.
10 Overcharge Observe for expansion, leakage, smoke, fire and
explosion.
11 Over-discharge Observe for expansion, leakage, smoke, fire and
explosion.
12 Short circuit Observe for expansion, leakage, smoke, fire and
explosion.
13 Drop Observe for expansion, leakage, smoke, fire and
explosion.
Safety
14 Extrusion Observe for expansion, leakage, smoke, fire and
performance
explosion.
15 Heating Observe for expansion, leakage, smoke, fire and
explosion.
16 Pin prick Observe for expansion, smoke, fire and explosion.
17 Low pressure Observe for expansion, leakage, smoke, fire and
explosion.
18 Thermal runaway Observe for fire and explosion when the thermal
runaway condition is reached.
6.2 Testing items of electrochemical capacitor modules for use in EES
The testing items of electrochemical capacitor modules for use in EES projects are shown in
Table 3.
Table 3 – Testing items of electrochemical capacitor modules
No. Testing Testing items Testing/checking parameters
category
1 Appearance Observe for deformation, cracks, bur, dirt,
arra
...