Lithium ion capacitors for use in electric and electronic equipment - Test methods for electrical characteristics

IEC 62813:2015 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.

Condensateurs au lithium-ion destinés à être utilisés dans les équipements électriques et électroniques - Méthodes d'essai relatives aux caractéristiques électriques

L'IEC 62813:2015 précise les méthodes d'essai applicables aux caractéristiques électriques (capacité, résistance interne, énergie électrique cumulée de décharge et taux de maintien de la tension) des condensateurs au lithium-ion (LIC - Lithium-Ion Capacitor) destinés à être utilisés dans les équipements électriques et électroniques.

General Information

Status
Published
Publication Date
07-Jan-2015
Current Stage
PPUB - Publication issued
Start Date
08-Jan-2015
Completion Date
08-Jan-2015
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IEC 62813
Edition 1.0 2015-01
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
IEC 62813:2015-01(en-fr)
---------------------- Page: 1 ----------------------
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---------------------- Page: 2 ----------------------
IEC 62813
Edition 1.0 2015-01
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
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 31.060.99 ISBN 978-2-8322-2196-9

Warning! Make sure that you obtained this publication from an authorized distributor.

Attention! Veuillez vous assurer que vous avez obtenu cette publication via un distributeur agréé.

® Registered trademark of the International Electrotechnical Commission
Marque déposée de la Commission Electrotechnique Internationale
---------------------- Page: 3 ----------------------
– 2 – IEC 62813:2015 © IEC 2015
CONTENTS

FOREWORD ......................................................................................................................... 3

1 Scope ............................................................................................................................ 5

2 Normative references..................................................................................................... 5

3 Terms and definitions .................................................................................................... 5

4 Test methods ................................................................................................................. 7

4.1 Test requirements ................................................................................................. 7

4.1.1 Standard atmospheric conditions for tests ...................................................... 7

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 .......................................................................................................... 12

4.3.1 Calculation of capacitance and discharge accumulated electric energy .......... 12

4.3.2 Calculation of internal resistance .................................................................. 13

4.3.3 Calculation of voltage maintenance rate ....................................................... 13

Annex A (informative) Endurance test (continuous application of rated voltage at high

temperature) ....................................................................................................................... 14

A.1 General ............................................................................................................... 14

A.2 Test procedure .................................................................................................... 14

A.2.1 Test conditions ............................................................................................ 14

A.2.2 Test procedure ............................................................................................. 14

A.2.3 Requirements .............................................................................................. 14

Annex B (informative) Calculation of the measuring currents based on the propagated

error ................................................................................................................................... 15

B.1 General ............................................................................................................... 15

B.2 Measurement propagated error and measuring currents ....................................... 15

Annex C (informative) Procedures for defining the measuring current of LIC with

uncertain nominal internal resistance .................................................................................. 17

C.1 General ............................................................................................................... 17

C.2 Defining procedures of measuring current for LIC ................................................ 17

Bibliography ....................................................................................................................... 18

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 ........................................................................................... 10

Figure 3 – Basic circuit for measuring the voltage maintenance rate .................................... 11

Figure 4 – Voltage profile for measuring voltage maintenance rate ....................................... 12

Figure C.1 – Flowchart of current setting procedures ........................................................... 17

---------------------- Page: 4 ----------------------
IEC 62813:2015 © IEC 2015 – 3 –
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 Reports, Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC

Publication(s)”). Their preparation is entrusted to technical committees; any IEC National Committee interested

in the subject dealt with may participate in this preparatory work. International, governmental and non-

governmental organizations liaising with the IEC also participate in this preparation. IEC collaborates closely

with the International Organization for Standardization (ISO) in accordance with conditions determined by

agreement between the two organizations.

2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international

consensus of opinion on the relevant subjects since each technical committee has representation from all

interested IEC National Committees.

3) IEC Publications have the form of recommendations for international use and are accepted by IEC National

Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC

Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any

misinterpretation by any end user.

4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications

transparently to the maximum extent possible in their national and regional publications. Any divergence

between any IEC Publication and the corresponding national or regional publication shall be clearly indicated in

the latter.

5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity

assessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any

services carried out by independent certification bodies.

6) All users should ensure that they have the latest edition of this publication.

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members of its technical committees and IEC National Committees for any personal injury, property damage or

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8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is

indispensable for the correct application of this publication.

9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of

patent rights. IEC shall not be held responsible for identifying any or all such patent rights.

International Standard IEC 62813 has been prepared by IEC technical committee 40:

Capacitors and resistors for electronic equipment.
The text of this standard is based on the following documents:
FDIS Report on voting
40/2322/FDIS 40/2341/RVD

Full information on the voting for the approval of this standard can be found in the report on

voting indicated in the above table.

This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.

---------------------- Page: 5 ----------------------
– 4 – IEC 62813:2015 © IEC 2015

The committee has decided that the contents of this publication will remain unchanged until

the stability date indicated on the IEC website under "http://webstore.iec.ch" in the data

related to the specific publication. At this date, the publication will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
---------------------- Page: 6 ----------------------
IEC 62813:2015 © IEC 2015 – 5 –
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, in whole or in part, are normatively referenced in this document and

are indispensable for its application. 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.
NOTE The terms printed in italics are those which are defined in this Clause 3.
3.1
upper category temperature
highest ambient temperature that a LIC is designed to operate continuously
[SOURCE: IEC 62576:2009, 3.3, modified]
3.2
rated voltage

maximum direct current (d.c.) 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]
3.3
rated lower limit voltage

minimum d.c. 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
---------------------- Page: 7 ----------------------
– 6 – IEC 62813:2015 © IEC 2015
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
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

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

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

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

voltage at the discharge start time (3.7) of a least-squares regression line over the time period

from the calculation start time (3.8) to the calculation end time (3.9) for the voltage drop

characteristic of a LIC during discharge
3.12
capacitance
ability of a LIC to store electrical charge
[SOURCE: IEC 62576:2009, 3.14, modified]
3.13
nominal capacitance
capacitance value designated by manufacturer, usually indicated on a LIC
[SOURCE: IEC 62576:2009, 3.15, modified]
---------------------- Page: 8 ----------------------
IEC 62813:2015 © IEC 2015 – 7 –
3.14
internal resistance

resistance component expressed in the equivalent series circuit of capacitance and resistance

of a LIC
[SOURCE: IEC 62391-1:2006, 2.2.20, modified]
3.15
nominal internal resistance
internal resistance value designated by manufacturer, usually indicated on a LIC
[SOURCE: IEC 62576:2009, 3.17, modified]
3.16
constant voltage charging
method of charging a LIC at specified constant voltage
[SOURCE: IEC 62576:2009, 3.18, modified]
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

charge, discharge, and storage of a LIC under specified atmospheric conditions (temperature,

humidity, and air pressure) before tests

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 62576:2009, 3.19, modified]
3.20
voltage maintenance rate

ratio of the voltage at the open-ended terminals to the charging voltage after a specified time

period subsequent to the charging of a LIC
[SOURCE: IEC 62576:2009, 3.26, modified]
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 %;
---------------------- Page: 9 ----------------------
– 8 – IEC 62813:2015 © IEC 2015
– 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 as given in IEC 60068-1:2013, 4.2, 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. The basic circuit is shown

in Figure 1.
a) D.C. power supply

The d.c. power supply shall be capable of charging the LIC at specified constant current

and specified constant voltage for specified duration.
b) Constant current load

The constant current load shall be capable of discharging the LIC at specified constant

current and its current rise time at discharge start shall be 50 ms or less.
c) D.C. voltage recorder

The d.c. 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.
---------------------- Page: 10 ----------------------
IEC 62813:2015 © IEC 2015 – 9 –
Power supply
constant current charging
V C
constant voltage charging
IEC
Key
I constant-current
U constant-voltage
D.C. ammeter
D.C. voltage recorder
S changeover switch
C LIC under test
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 d.c. power supply specified in 4.2.1.1 and with

specified current I calculated by Formula (1).
1 27 26
(1)
I = 1 + −
30R 5C R + 1 10C R + 1
N N N N N
where
---------------------- Page: 11 ----------------------
– 10 – IEC 62813:2015 © IEC 2015

I is the charging current (A). It is also used to specify the discharging current;

R is the nominal internal resistance of the LIC under test (Ω);
C is the nominal capacitance of the LIC under test (F).

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

constant voltage charging then apply the rated voltage U for 30 min.
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: tenth of I calculated by Formula (1).
f) Test, measurement and recording
Measure and record the voltage-time characteristics between the LIC terminals
1) Sampling and recording interval shall be set to 100 ms.

2) Sampling and recording shall be conducted continuously from charge start time to the

time to reach rated lower limit voltage U .
T T T
0 1 L
Time
IEC
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)
T duration of constant voltage charging (s)
U rated voltage (V)
U rated lower limit voltage (V)
U instant drop voltage at discharge (V)
Figure 2 – Voltage profile for measuring capacitance, discharge
accumulated electric energy, and internal resistance
Voltage
---------------------- Page: 12 ----------------------
IEC 62813:2015 © IEC 2015 – 11 –
4.2.2 Measurement for voltage maintenance rate
4.2.2.1 Test equipment

The basic circuit is shown in Figure 3. The d.c. 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.
Power supply
constant current charging
V V
1 x 2
constant voltage charging
IEC
Key
V V
1 2 D.C. 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 d.c. power supply specified in 4.2.1.1 and with

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

constant voltage charging then apply the rated voltage U for 24 h.
e) Terminal opening
Disconnect the LIC terminals from the circuit.
f) Measurement
Measure voltage between the LIC terminals when T is 72 h (see Figure 4).
---------------------- Page: 13 ----------------------
– 12 – IEC 62813:2015 © IEC 2015
end
oc Time
IEC
Key
T duration of measurement, which is set to 72 h (h)
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

The capacitance C shall be calculated by Formula (2) and the discharge accumulated

electric energy W shall be calculated by Formula (3) (see Figure 2).
C = (2)
2 2
U −U
0 L
n−1
W = (V + V ) (3)
k+1 k
200
k=0
where
C is the capacitance (F) of the LIC;

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);
V is the measured voltage at sampling point k (V).

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 simplifie
...

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