IEC 62813:2025

IEC 62813 ®
Edition 2.0 2025-01
REDLINE VERSION
INTERNATIONAL
STANDARD
colour
inside
Lithium-ion capacitors for use in electric and electronic equipment –
Test methods for electrical characteristics

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IEC 62813 ®
Edition 2.0 2025-01
REDLINE VERSION
INTERNATIONAL
STANDARD
colour
inside
Lithium-ion capacitors for use in electric and electronic equipment –
Test methods for electrical characteristics
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 31.060.99 ISBN 978-2-8327-0150-8

– 2 – IEC 62813:2025 RLV © IEC 2025
CONTENTS
FOREWORD . 3
1 Scope . 5
2 Normative references . 5
3 Terms and definitions . 5
4 Test methods . 8
4.1 Test requirements . 8
4.1.1 Standard atmospheric conditions for tests . 8
4.1.2 Standard atmospheric conditions for measurements . 8
4.1.3 Pre-conditioning . 8
4.2 Measurement . 8
4.2.1 Capacitance, discharge accumulated electric energy, and internal
resistance . 8
4.2.2 Measurement for voltage maintenance rate . 13
4.3 Calculation . 15
4.3.1 Calculation of capacitance and discharge accumulated electric energy . 15
4.3.2 Calculation of internal resistance . 17
4.3.3 Calculation of voltage maintenance rate . 18
Annex A (informative) Endurance test (continuous application of rated voltage at high
temperature) . 19
A.1 General . 19
A.2 Test procedure . 19
A.2.1 Test conditions . 19
A.2.2 Test procedure . 19
A.2.3 Requirements . 19
Annex B (informative) Calculation of the measuring currents based on the propagated
error . 21
B.1 General . 21
B.2 Measurement propagated error and measuring currents . 21
Annex C (informative) Procedures for defining the measuring current of LIC with
uncertain nominal internal resistance . 24
C.1 General . 24
C.2 Defining procedures of measuring current for LIC . 24
Bibliography . 25

Figure 1 – Basic circuit for measuring capacitance, discharge accumulated electric
energy, and internal resistance . 11
Figure 2 – Voltage profile for measuring capacitance, discharge accumulated electric
energy, and internal resistance . 13
Figure 3 – Basic circuit for measuring the voltage maintenance rate . 14
Figure 4 – Voltage profile for measuring voltage maintenance rate . 15
Figure C.1 – Flowchart of current setting procedures . 24

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
LITHIUM-ION CAPACITORS FOR USE
IN ELECTRIC AND ELECTRONIC EQUIPMENT –
TEST METHODS FOR ELECTRICAL CHARACTERISTICS

FOREWORD
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– 4 – IEC 62813:2025 RLV © IEC 2025
IEC 62813 has been prepared by IEC technical committee 40: Capacitors and resistors for
electronic equipment. It is an International Standard.
This second edition cancels and replaces the first edition published in 2015. This edition
constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) The document has been restructured to comply with the ISO/IEC Directives, Part 2.
The text of this International Standard is based on the following documents:
Draft Report on voting
40/3178/FDIS 40/3195/RVD
Full information on the voting for its approval can be found in the report on voting indicated in
the above table.
The language used for the development of this International Standard is English.
This document was drafted in accordance with ISO/IEC Directives, Part 2, and developed in
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• reconfirmed,
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LITHIUM-ION CAPACITORS FOR USE
IN ELECTRIC AND ELECTRONIC EQUIPMENT –
TEST METHODS FOR ELECTRICAL CHARACTERISTICS

1 Scope
This International Standard specifies the electrical characteristics (capacitance, internal
resistance, discharge accumulated electric energy, and voltage maintenance rate) test methods
of lithium-ion capacitors (LIC) for use in electric and electronic equipment.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies.
For undated references, the latest edition of the referenced document (including any
amendments) applies.
IEC 60068-1:2013, Environmental testing – Part 1: General and guidance
3 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
NOTE The terms printed in italics are those which are defined in this Clause 3.
3.1
upper category temperature
highest ambient temperature including internal heating in which a LIC is designed to operate
continuously
[SOURCE: IEC 62576:2009, 3.3, modified IEC 61881-3:2012, 3.17, modified – The note to entry
has been deleted.]
3.2
rated voltage
U
R
maximum direct current (DC) voltage that may be applied continuously for a certain time under
the upper category temperature (3.1) to a LIC so that it can exhibit specified demand
characteristics
Note 1 to entry: This voltage is the setting voltage in LIC design.
Note 2 to entry: The endurance test using the rated voltage is described in Annex A.
[SOURCE: IEC 62576:2009, 3.6, modified IEC 62576:2018, 3.20, modified – The word
"capacitor" has been replaced by "LIC".]

– 6 – IEC 62813:2025 RLV © IEC 2025
3.3
rated lower limit voltage
U
L
minimum DC voltage such that a LIC can exhibit specified demand characteristics
Note 1 to entry: The rated lower limit voltage is designated by manufacturer.
3.4
charging current
current required to charge a LIC
3.5
discharging current
current required to discharge a LIC
3.6
discharge accumulated electric energy
amount of discharged energy of a LIC accumulated from the discharge start time (3.7) to the
time to reach rated lower limit voltage (3.10)
3.7
discharge start time
T
time when discharge of a LIC starts
Note 1 to entry: It is the basis time for the calculation start time (3.8) and the time to reach rated lower limit voltage
(3.10).
3.8
calculation start time
T
time at a selected start point used to calculate the capacitance (3.12) and the internal resistance
(3.14) during discharge of a LIC
Note 1 to entry: The calculation start time is expressed as elapsed time since the discharge start time (3.7).
3.9
calculation end time
T
time at a selected end point used to calculate the capacitance (3.12) and the internal resistance
(3.14) during discharge of a LIC
Note 1 to entry: The calculation end time is expressed as elapsed time since the discharge start time (3.7).
3.10
time to reach rated lower limit voltage
T
L
time when the voltage reaches the rated lower limit voltage (3.3) during discharge of a LIC
Note 1 to entry: The time to reach rated lower limit voltage is expressed as elapsed time since the discharge start
time (3.7).
3.11
instant drop voltage at discharge
U
voltage at the discharge start time (3.7) of a least-squares regression line over the time period
calculation start time (3.8) to the calculation end time (3.9) for the voltage drop
from the
characteristic of a LIC during discharge

3.12
capacitance
ability of a LIC to store electrical charge (F)
[SOURCE: IEC 62576:20092018, 3.5, modified – The word “capacitor” has been replaced by
“LIC”.]
3.13
nominal capacitance
C
N
designated capacitance value designated by manufacturer, usually indicated on a LIC
[SOURCE: IEC 62576:2009, 3.15, modified IEC 62391-1:2022, 3.21, modified – The words "on
the capacitor" have been replaced by "on a LIC".]
3.14
internal resistance
resistance component in an equivalent series circuit of capacitance and resistance of a LIC
[SOURCE: IEC 62391-1:2006, 2.2.20, modified IEC 62391-1:2022, 3.10, modified – The words
"resistance of a capacitor" have been replaced by "resistance of a LIC".]
3.15
nominal internal resistance
R
N
internal resistance value designated by manufacturer, usually indicated on a LIC
[SOURCE: IEC 62576:2009, 3.17, modified]
nominal value of the internal resistance to be used in design and measurement condition
setting, generally at the ambient temperature
[SOURCE: IEC 62576:2018, 3.17, modified – The information given between parentheses
"(R )" and "(Ω)" have been removed from the descriptive statement.]
N
3.16
constant voltage charging
method of charging a LIC at specified constant voltage
charging during which the voltage is maintained at a constant value regardless of charge current
or temperature
[SOURCE: IEC 62576:20092018, 3.18, modified 3.9]
3.17
constant current charging
method of charging a LIC with specified constant current
3.18
constant current discharging
method of discharging a LIC with specified constant current
3.19
pre-conditioning
charging and discharging and storage of a LIC under specified atmospheric ambient conditions
(temperature, humidity, and air pressure) before testing

– 8 – IEC 62813:2025 RLV © IEC 2025
Note 1 to entry: Generally, pre-conditioning implies that the LIC is stored until its inner temperature attains thermal
equilibrium with the surrounding temperature, before its electrical characteristics are measured.
[SOURCE: IEC 62576:20092018, 3.19, modified – The word "capacitor" has been replaced by
"LIC" in the definition and in the note.]]
3.20
voltage maintenance rate
A
ratio of the voltage at the open-ended terminals to the charge voltage after a specified time
period subsequent to the charging of a LIC
[SOURCE: IEC 62576:20092018, 3.25, modified – The word "capacitor" has been replaced by
"LIC".]
4 Test methods
4.1 Test requirements
4.1.1 Standard atmospheric conditions for tests
Unless otherwise specified in the detail specification, all tests shall be made under standard
atmospheric conditions for tests as given in IEC 60068-1:2013, 4.3:
– temperature: 15 °C to 35 °C;
– relative humidity: 25 % to 75 %;
– air pressure: 86 kPa to 106 kPa.
If any question about determining measurement value arises under the atmospheric conditions
or if it is requested, 4.1.2 is applied.
If it is difficult to perform measurements under the standard atmospheric conditions and if no
question about determining measurement value arises, tests and measurements may be
performed under other conditions than the standard atmospheric conditions.
4.1.2 Standard atmospheric conditions for measurements
Unless otherwise specified in the detail specification, all measurements shall be made under
standard atmospheric conditions for measurements testing as given in IEC 60068-1:2013, 4.3,
with the following details:
– temperature: 25 °C ± 2 °C;
– relative humidity: 45 % to 55 %;
– air pressure: 86 kPa to 106 kPa.
4.1.3 Pre-conditioning
Unless otherwise specified in the detail specification, the LIC shall be charged with a constant
current and constant voltage power supply, the voltage of which is set to the rated voltage, for
30 min then discharged to the lower limit voltage with a proper discharging device.
4.2 Measurement
4.2.1 Capacitance, discharge accumulated electric energy, and internal resistance
4.2.1.1 Test equipment
The test equipment shall be capable of constant current charging, constant voltage charging,
and constant current discharging with current specified in 4.2.1.2, and continuous measurement

of current and voltage at specified sampling interval specified in 4.2.1.2 f) 1). The basic circuit
is shown in Figure 1.
a) DC power supply
The DC power supply shall be capable of charging the LIC at specified constant current
specified in 4.2.1.2 c) and specified constant voltage specified in 4.2.1.2 d) for duration
specified in 4.2.1.2 d).
b) Constant current load
The constant current load shall be capable of discharging the LIC at specified constant
current specified in 4.2.1.2 e) and its current rise time at discharge start shall be 50 ms or
less.
c) DC voltage recorder
The DC voltage recorder shall be capable of conducting measurements and recording with
1 mV resolution and sampling interval of 100 ms.
d) Changeover switch
The changeover switch shall not cause chattering which may affect the result of voltage-
time recording.
– 10 – IEC 62813:2025 RLV © IEC 2025

Power supply
A
I
CC
S
+
constant current charging
V C
x
U
CV
constant voltage charging
IEC
Key
I constant-current
CC
U constant-voltage
CV
A
D.C. ammeter
V
D.C. voltage recorder
S changeover switch
C LIC under test
x
constant current power supply
constant voltage power supply
constant current load
Key
I constant-current
CC
U constant-voltage
CV
A
DC ammeter
DC voltage recorder
V
S changeover switch
C LIC under test
x
constant current power supply
constant voltage power supply
constant current load
Figure 1 – Basic circuit for measuring capacitance, discharge
accumulated electric energy, and internal resistance
4.2.1.2 Measurement procedure and conditions
The measurement procedure and conditions shall be as follows. The voltage profile between
the LIC terminals in the measurement shall be as shown in Figure 2.
a) Before setting sample
The LIC shall be left in the standard atmospheric condition as defined in 4.1.1 for 2 h to 6 h.
b) Sample setting
Connect the LIC terminals to the circuit.
c) Constant current charging
Charge the LIC to the rated voltage U with DC power supply specified in 4.2.1.1 and with
R
specified current I calculated by Formula (1).
1 27 26
I= 1+ −
(1)
30R 5CR ++1 10CR 1
N NN NN
where
I is the charging current (A). It is also used to specify the discharging current;

– 12 – IEC 62813:2025 RLV © IEC 2025
R is the nominal internal resistance of the LIC under test (Ω);
N
C is the nominal capacitance of the LIC under test (F).
N
NOTE The current calculated by Formula (1) is assumed as the current by which the resultant measurement
error of the internal resistance is limited within ± 3 % (see Annex B). When the nominal value of internal
resistance is uncertain, the current for the measurement can be set according to the advisable procedures
described in Annex C.
d) Constant voltage charging
When voltage between the LIC terminals is reached to the rated voltage U , switch to
R
constant voltage charging then apply the rated voltage U for 30 min.
R
e) Constant current discharging
Turn changeover switch from the power supply to the constant current load and discharge
with the specified constant current as follows:
1) For internal resistance measurement, set the discharge current: I calculated by
Formula (1).
2) For discharge accumulated electric energy and capacitance measurement, set the
discharge current: I , tenth of I calculated by Formula (1).
cap
f) Test, measurement and recording
Measure and record the voltage-time characteristics between the LIC terminals:
1) Sampling and recording interval ∆T shall be set to 100 ms 0,1 s.
s
2) Sampling and recording shall be conducted continuously from charge start time to the
time to reach rated lower limit voltage U .
L
Key
T discharge start time (s)
T calculation start time, which is set to C R (s)
1 N N
T calculation end time, which is set to 2 C R (s)
2 N N
T time to reach rated lower limit voltage (s)
L
T duration of constant voltage charging (s)
CV
U rated voltage (V)
R
U rated lower limit voltage (V)
L
U instant drop voltage at discharge (V)
Figure 2 – Voltage profile for measuring capacitance, discharge
accumulated electric energy, and internal resistance
4.2.2 Measurement for voltage maintenance rate
4.2.2.1 Test equipment
The basic circuit is shown in Figure 3. The DC voltmeters V and V shall have a resolution of
1 2
5 mV or less for voltage measurement. The input impedance shall be sufficiently high so that
measurement errors are negligible.

– 14 – IEC 62813:2025 RLV © IEC 2025
Power supply
I
CC
S
+
constant current charging
V C V
x
1 2
U
CV
constant voltage charging
IEC
Key
V V
1 2 D.C. voltmeter
Key
V V
2 1
DC voltmeter
Figure 3 – Basic circuit for measuring the voltage maintenance rate
4.2.2.2 Measurement procedure and conditions
The measurement procedure and conditions shall be as follows. The voltage profile between
the LIC terminals in the measurement shall be as shown in Figure 4.
a) Before setting sample
The LIC shall be left in the standard atmospheric condition as defined in 4.1.1 for 2 h to 6 h.

b) Sample setting
Connect the LIC terminals to the circuit.
c) Constant current charging
Charge the LIC to the rated voltage U with DC power supply specified in 4.2.1.1 and with
R
specified current I calculated by Formula (1).
d) Constant voltage charging
When voltage between the LIC terminals is reached to the rated voltage U , switch to the
R
constant voltage charging then apply the rated voltage U for 24 h.
R
e) Terminal opening
Disconnect the LIC terminals from the circuit.
f) Measurement
Measure voltage between the LIC terminals when the leaving time after terminal opening
T is 72 h (see Figure 4).
OC
Key
T duration of measurement, which is set to 72 h (h)
oc
U voltage between the LIC terminals at T (V)
end oc
Figure 4 – Voltage profile for measuring voltage maintenance rate
4.3 Calculation
4.3.1 Calculation of capacitance and discharge accumulated electric energy
The capacitance and the discharge accumulated electric energy are calculated by using the
energy conversion method described in a). When agreed between manufacturer and customer,
simplified method described in b) can be used instead.
a) Calculation of capacitance and accumulated electric energy by energy conversion method
shall be calculated by Formula (2) and the discharge accumulated
The capacitance C
x
electric energy W shall be calculated by Formula (3) (see Figure 2).

– 16 – IEC 62813:2025 RLV © IEC 2025
2W
C =
(2)
x
2 2
U −U
0 L
n−1
I
W = (V +V )
(3)
k+1 k
∑
k=0
2W
C =
(2)
x
UU−
0L
ITΔ
cap s n−1
(3)
W VV+
( )
∑ kk+1
k=0
where
C is the capacitance of the LIC (F) ;
x
W is the discharge accumulated electric energy, which is time integral of the electric
power on all sampling points from discharge start sampling point (k = 0) to discharge
end sampling point (k = n);
U is the instant drop voltage at discharge (V);
U is the rated lower limit voltage (V);
L
I is the discharge current (A): tenth of I calculated by Formula (1);
cap
∆T is the sampling and recording interval (s): set to 0,1 s;
s
V is the measured voltage at sampling point k (V).
k
The discharge accumulated electric energy represented in watt-hour notation is calculated
by dividing W by 3 600.
b) Calculation of capacitance and accumulated electric energy by simplified method
The capacitance C shall be calculated by Formula (4) and the discharge accumulated
x
electric energy W shall be calculated by Formula (5) (see Figure 2).

=
I(T −T )
L 0
C = (4)
x
10(U −U )
0 L
2 2
C (U −U )
x 0 L
W = (5)
IT()−T
L0
C =
(4)
x
10(UU− )
0L
CU()−U
x0 L
(5)
W =
where
C is the capacitance of the LIC (F);
x
I is the discharge current (A);

T is the time to reach rated lower limit voltage (s);
L
T is the discharge start time (s);
U is the instant drop voltage at discharge (V);
U is the rated lower limit voltage (V);
L
W is the discharge accumulated electric energy (J).
The discharge accumulated electric energy represented in watt-hour notation is calculated
by dividing W by 3 600.
4.3.2 Calculation of internal resistance
The internal resistance R is calculated by Formula (6) (see Figure 2).
x
UU−
R 0
R = (6)
x
I
where
R is the internal resistance of the LIC (Ω);
x
U is the rated voltage of the LIC (V);
R
U is the instant drop voltage at discharge (V);
I is the discharge current (A).

– 18 – IEC 62813:2025 RLV © IEC 2025
4.3.3 Calculation of voltage maintenance rate
The voltage maintenance rate A is calculated by Formula (7) (see Figure 4).
U
end
A ×100
(7)
U
R
where
A is the voltage maintenance rate of the LIC (%);
U is the voltage between the LIC terminals at T (V);
end oc
U is the rated voltage of the LIC (V).
R
=
Annex A
(informative)
Endurance test (continuous application
of rated voltage at high temperature)
A.1 General
This Annex A describes the endurance test for continuous application of rated voltage at high
temperature to determine the rated voltage defined in 3.2.
A.2 Test procedure
A.2.1 Test conditions
Unless otherwise given in the relevant specification, the test conditions should be as follows:
– temperature: upper category temperature;
– voltage: rated voltage;
– duration 1 000 h.
A.2.2 Test procedure
The test procedure should be as follows.
a) Initial measurements
Measure and calculate capacitance and internal resistance by the measurement procedure
described in 4.2.1 and the calculation method described in 4.3.1 and 4.3.2.
b) Testing
Place the LIC in a chamber at the upper category temperature and charge it up to the rated
voltage with current calculated by Formula (1) then keep the voltage for specified duration.
c) Final measurements
Measure and calculate capacitance and internal resistance as described in a). The rates of
change can be obtained in comparison to their initially measured values.
A.2.3 Requirements
Unless otherwise agreed between manufacturer and customer, the capacitance change ∆C and
internal resistance change ∆R should meet the following values.

– 20 – IEC 62813:2025 RLV © IEC 2025
CC−
fi
ΔC ×≤100% 20%
C
i
where
∆C is the capacitance change;
C is the initial capacitance before the test (F);
i
C is the capacitance after the test (F).
f
RR−
f i
ΔR ×100%≤ 50%
R
i
where
∆R is the internal resistance change;
R is the initial internal resistance before the test (Ω);
i
R is the internal resistance after the test (Ω).
f
=
=
Annex B
(informative)
Calculation of the measuring currents based on the propagated error
B.1 General
This Annex B describes the calculation of the measuring currents provided in 4.2.1.2,
Formula (1).
B.2 Measurement propagated error and measuring currents
The internal resistance R is calculated from Formula (B.1):
()UU−
R 0
(B.1)
R =
I
where
R is the internal resistance (Ω);
U is the rated voltage (V);
R
U is the instant drop voltage at discharge (V);
I is the discharge current (A).
From the formula of propagated error, the relative error of R is expressed as follows:
δU +δU
δR  δI 
R0
+
(B.2)
   
RI
   
()UU−
R 0
where
R is the internal resistance (Ω);
δ R is the error of the internal resistance (Ω);
U is the rated voltage (V);
R
δ U is the error of the charge voltage (V);
R
U is the instant drop voltage at discharge (V);
δ U is the error of the instant drop voltage at discharge (V);
I is the discharge current (A);
δI is the error of the discharge current (A).
δI /I is small enough to be ignorable. When the measuring voltage corresponding to
explanatory variable t at each sampling point is random variable, U is expressed as follows
i 0
from the formula of propagated error of least-square method as follows.

=
– 22 – IEC 62813:2025 RLV © IEC 2025
t
∑
i
δU =δU (B.3)
N t − ()t
∑∑i i
where
δ U is the error of the instant drop voltage at discharge (V);
δ U are the voltage measurement errors at each sampling point (V);
N is a number of sampling points;
t is a time of each sampling point;
i
δ U is also assumed to be equal to δ U.
R
N is a number of sampling points. The voltage measurement errors at each sampling point are
assumed to be equal to δU at each sampling point. And δU is also assumed to be equal to
R
δU
.
When Δt is the sampling interval, the following formula applies:
t= ()T−ΔΔt+it
(B.4)
i1
where
t is a time of each sampling point;
i
T is the calculation start time, which is set to C R (s);
1 N N
∆t is the sampling interval (s);
i is the number of sampling times for each.
Assigning this to Formula (B.3) gives:
13 2T
δU δU + +−N 1 (B.5)
0 
NtΔ
NN( −1) 
where
δ U is the error of the instant drop voltage at discharge (V);
δ U are the voltage measurement errors at each sampling point (V);
N is a number of sampling points;
t is a time of each sampling point;
i
∆t is the sampling interval (s).
By assigning Formula (B.5) to Formula (B.2) and by the condition that the relative error δR /R
of internal resistance is limited within ±3 %, Formula (B.6) is given.
Formula (1) is obtained by Formulas (B.6). and (B.7), using to 0,1 s and δU = 1 mV.
Δt
=
δU 13 2T

(B.6)
IN11++ +−

0,03RN Δt
NN( −1) 
(TT− )
2 1
N +1 (B.7)
Δt
where
δ U are the voltage measurement errors at each sampling point (V);
R is the internal resistance (Ω);
N is a number of sampling points;
is the calculation start time, which is set to C R (s);
T
1 N N
T is the calculation end time, which is set to 2 C R (s);
2 N N
∆t is the sampling interval (s).

=
=
– 24 – IEC 62813:2025 RLV © IEC 2025
Annex C
(informative)
Procedures for defining the measuring current
of LIC with uncertain nominal internal resistance
C.1 General
This Annex C describes the defining procedures of measuring current provided in Annex B for
the LIC which has uncertain nominal internal resistance.
C.2 Defining procedures of measuring current for LIC
When the nominal value of internal resistance of the LIC is uncertain, the current for the
measurement of the LIC can be set according to the following procedures (see Figure C.1):
a) Using an estimated value of internal resistance (R ), measure and calculate internal
est
resistance by the measurement procedure described in 4.2.1 and the calculation method
described in 4.3.2.
b) Using the resultant internal resistance (R ) calculated in a) as a new estimated value,
res
repeat the process described in a).
c) Repeat b) until the difference between R and R becomes less than 10 % of R .
est res est
However, when the instant drop voltage at discharge U becomes less or equal to the rated
lower limit voltage U , try procedures from a) to c) again with smaller current. When R
L res
indicates a negative value, try from a) to c) again with larger current.

Figure C.1 – Flowchart of current setting procedures

Bibliography
IEC 61881-3:2012, Railway applications – Rolling stock equipment – Capacitors for power
electronics – Part 3: Electric double-layer capacitors
IEC 62391-1:20062022, Fixed electric double-layer capacitors for use in electric and electronic
equipment – Part 1: Generic specification
IEC 62576:20092018, Electric double-layer capacitors for use in hybrid electric vehicles – Test
methods for electrical characteristics

___________
IEC 62813 ®
Edition 2.0 2025-01
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Lithium-ion capacitors for use in electric and electronic equipment –
Test methods for electrical characteristics

Condensateurs au lithium-ion destinés à être utilisés dans les équipements
électriques et électroniques – Méthodes d'essai relatives aux caractéristiques
électriques
– 2 – IEC 62813:2025 © IEC 2025
CONTENTS
FOREWORD . 3
1 Scope . 5
2 Normative references . 5
3 Terms and definitions . 5
4 Test methods . 8
4.1 Test requirements . 8
4.1.1 Standard atmospheric conditions for tests . 8
4.1.2 Standard atmospheric conditions for measurements . 8
4.1.3 Pre-conditioning . 8
4.2 Measurement . 8
4.2.1 Capacitance, discharge accumulated electric energy, and internal
resistance . 8
4.2.2 Measurement for voltage maintenance rate . 11
4.3 Calculation . 13
4.3.1 Calculation of capacitance and discharge accumulated electric energy . 13
4.3.2 Calculation of internal resistance . 14
4.3.3 Calculation of voltage maintenance rate . 15
Annex A (informative) Endurance test (continuous application of rated voltage at high
temperature) . 16
A.1 General . 16
A.2 Test procedure . 16
A.2.1 Test conditions . 16
A.2.2 Test procedure . 16
A.2.3 Requirements . 16
Annex B (informative) Calculation of the measuring currents based on the propagated
error . 18
B.1 General . 18
B.2 Measurement propagated error and measuring currents . 18
Annex C (informative) Procedures for defining the measuring current of LIC with
uncertain nominal internal resistance . 21
C.1 General . 21
C.2 Defining procedures of measuring current for LIC . 21
Bibliography . 22

Figure 1 – Basic circuit for measuring capacitance, discharge accumulated electric
energy, and internal resistance . 9
Figure 2 – Voltage profile for measuring capacitance, discharge accumulated electric
energy, and internal resistance . 11
Figure 3 – Basic circuit for measuring the voltage maintenance rate . 12
Figure 4 – Voltage profile for measuring voltage maintenance rate . 13
Figure C.1 – Flowchart of current setting procedures . 21

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
LITHIUM-ION CAPACITORS FOR USE
IN ELECTRIC AND ELECTRONIC EQUIPMENT –
TEST METHODS FOR ELECTRICAL CHARACTERISTICS

FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote international
co-operation on all questions concerning standardization in the electrical and electronic fields. To this end and
in addition to other activities, IEC publishes International Standards, Technical Specifications, Technical Re
...