IEC 61951-1:2017

IEC 61951-1 ®
Edition 4.0 2017-03
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Secondary cells and batteries containing alkaline or other non-acid
electrolytes – Secondary sealed cells and batteries for portable applications –
Part 1: Nickel-cadmium
Accumulateurs alcalins et autres accumulateurs à électrolyte non acide –
Accumulateurs étanches pour applications portables –
Partie 1: Nickel-cadmium
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form
or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from
either IEC or IEC's member National Committee in the country of the requester. If you have any questions about IEC
copyright or have an enquiry about obtaining additional rights to this publication, please contact the address below or
your local IEC member National Committee for further information.

Droits de reproduction réservés. Sauf indication contraire, aucune partie de cette publication ne peut être reproduite
ni utilisée sous quelque forme que ce soit et par aucun procédé, électronique ou mécanique, y compris la photocopie
et les microfilms, sans l'accord écrit de l'IEC ou du Comité national de l'IEC du pays du demandeur. Si vous avez des
questions sur le copyright de l'IEC ou si vous désirez obtenir des droits supplémentaires sur cette publication, utilisez
les coordonnées ci-après ou contactez le Comité national de l'IEC de votre pays de résidence.

IEC Central Office Tel.: +41 22 919 02 11
3, rue de Varembé Fax: +41 22 919 03 00
CH-1211 Geneva 20 info@iec.ch
Switzerland www.iec.ch
About the IEC
The International Electrotechnical Commission (IEC) is the leading global organization that prepares and publishes
International Standards for all electrical, electronic and related technologies.

About IEC publications
The technical content of IEC publications is kept under constant review by the IEC. Please make sure that you have the
latest edition, a corrigenda or an amendment might have been published.

IEC Catalogue - webstore.iec.ch/catalogue Electropedia - www.electropedia.org
The stand-alone application for consulting the entire The world's leading online dictionary of electronic and
bibliographical information on IEC International Standards, electrical terms containing 20 000 terms and definitions in
Technical Specifications, Technical Reports and other English and French, with equivalent terms in 16 additional
documents. Available for PC, Mac OS, Android Tablets and languages. Also known as the International Electrotechnical
iPad. Vocabulary (IEV) online.

IEC publications search - www.iec.ch/searchpub IEC Glossary - std.iec.ch/glossary
The advanced search enables to find IEC publications by a 65 000 electrotechnical terminology entries in English and
variety of criteria (reference number, text, technical French extracted from the Terms and Definitions clause of
committee,…). It also gives information on projects, replaced IEC publications issued since 2002. Some entries have been
and withdrawn publications. collected from earlier publications of IEC TC 37, 77, 86 and

CISPR.
IEC Just Published - webstore.iec.ch/justpublished
Stay up to date on all new IEC publications. Just Published IEC Customer Service Centre - webstore.iec.ch/csc
details all new publications released. Available online and If you wish to give us your feedback on this publication or
also once a month by email. need further assistance, please contact the Customer Service
Centre: csc@iec.ch.
A propos de l'IEC
La Commission Electrotechnique Internationale (IEC) est la première organisation mondiale qui élabore et publie des
Normes internationales pour tout ce qui a trait à l'électricité, à l'électronique et aux technologies apparentées.

A propos des publications IEC
Le contenu technique des publications IEC est constamment revu. Veuillez vous assurer que vous possédez l’édition la
plus récente, un corrigendum ou amendement peut avoir été publié.

Catalogue IEC - webstore.iec.ch/catalogue Electropedia - www.electropedia.org
Application autonome pour consulter tous les renseignements
Le premier dictionnaire en ligne de termes électroniques et
bibliographiques sur les Normes internationales,
électriques. Il contient 20 000 termes et définitions en anglais
Spécifications techniques, Rapports techniques et autres
et en français, ainsi que les termes équivalents dans 16
documents de l'IEC. Disponible pour PC, Mac OS, tablettes
langues additionnelles. Egalement appelé Vocabulaire
Android et iPad.
Electrotechnique International (IEV) en ligne.

Recherche de publications IEC - www.iec.ch/searchpub
Glossaire IEC - std.iec.ch/glossary
65 000 entrées terminologiques électrotechniques, en anglais
La recherche avancée permet de trouver des publications IEC
en utilisant différents critères (numéro de référence, texte, et en français, extraites des articles Termes et Définitions des
comité d’études,…). Elle donne aussi des informations sur les publications IEC parues depuis 2002. Plus certaines entrées
projets et les publications remplacées ou retirées. antérieures extraites des publications des CE 37, 77, 86 et

CISPR de l'IEC.
IEC Just Published - webstore.iec.ch/justpublished

Service Clients - webstore.iec.ch/csc
Restez informé sur les nouvelles publications IEC. Just
Published détaille les nouvelles publications parues. Si vous désirez nous donner des commentaires sur cette
Disponible en ligne et aussi une fois par mois par email. publication ou si vous avez des questions contactez-nous:
csc@iec.ch.
IEC 61951-1 ®
Edition 4.0 2017-03
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Secondary cells and batteries containing alkaline or other non-acid

electrolytes – Secondary sealed cells and batteries for portable applications –

Part 1: Nickel-cadmium
Accumulateurs alcalins et autres accumulateurs à électrolyte non acide –

Accumulateurs étanches pour applications portables –

Partie 1: Nickel-cadmium
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 29.220.30 ISBN 978-2-8322-4010-6

– 2 – IEC 61951-1:2017 © IEC 2017
CONTENTS
FOREWORD . 5
1 Scope . 7
2 Normative references . 7
3 Terms and definitions . 7
4 Parameter measurement tolerances . 9
5 Cell and battery designation and marking . 9
5.1 Cell and battery designation . 9
5.1.1 Small prismatic cells and cylindrical cells . 9
5.1.2 Button cells. 11
5.1.3 Batteries . 11
5.2 Cell or battery termination . 11
5.3 Marking . 11
5.3.1 Small prismatic cells and cylindrical cells . 11
5.3.2 Button cells. 12
5.3.3 Batteries . 12
5.4 Exemption of wording. 12
6 Dimensions. 12
6.1 Small prismatic cells and cylindrical cells . 12
6.1.1 General . 12
6.1.2 Small prismatic cells . 13
6.1.3 Cylindrical cells . 13
6.2 Button cells . 15
7 Electrical tests . 16
7.1 General . 16
7.2 Charging procedure for test purposes . 16
7.2.1 Charging procedure for cell. 16
7.2.2 Charging procedure for battery . 16
7.3 Discharge performance . 17
7.3.1 General . 17
7.3.2 Discharge performance at 20 °C . 17
7.3.3 Discharge performance at –18 °C . 19
7.3.4 Discharge performance for rapid charge cells (R cells) . 20
7.4 Charge (capacity) retention . 20
7.5 Endurance . 20
7.5.1 Endurance in cycles. 20
7.5.2 Permanent charge endurance . 24
7.6 Charge acceptance at constant voltage . 28
7.7 Overcharge . 28
7.7.1 Small prismatic cells . 28
7.7.2 L, M, H or X cylindrical and button cells . 29
7.7.3 LT/LU, MT/MU or HT/HU cylindrical cells . 29
7.7.4 J cylindrical cells . 29
7.7.5 JT cylindrical cells . 30
7.7.6 R cylindrical cells . 30
7.8 Safety device operation . 31

7.9 Button cells or batteries storage, small prismatic cells or batteries storage,
cylindrical cells or batteries storage . 31
7.10 Charge acceptance at +55 °C for LT, MT or HT cylindrical cells . 32
7.11 Trickle charge acceptance for JT cylindrical cells . 32
7.12 Internal resistance . 33
7.12.1 General . 33
7.12.2 Measurement of the internal AC resistance . 33
7.12.3 Measurement of the internal DC resistance . 34
8 Mechanical tests . 34
9 Safety requirements . 34
10 Type approval and batch acceptance . 34
10.1 General . 34
10.2 Type approval . 35
10.2.1 Type approval for small prismatic cells . 35
10.2.2 Type approval for cylindrical and button cells . 35
10.2.3 Type approval for batteries . 37
10.3 Batch acceptance . 38
Bibliography . 40

Figure 1 – Jacketed cylindrical cells . 13
Figure 2 – Jacketed small prismatic cells . 13
Figure 3 – Jacketed cells dimensionally interchangeable with primary cells . 14
Figure 4 – Button cells . 15

Table 1 – Dimensions of jacketed small prismatic cells . 13
Table 2 – Dimensions of jacketed cylindrical cells dimensionally interchangeable with
primary cells . 14
Table 3 – Dimensions of jacketed cylindrical cells not dimensionally interchangeable
with primary cells . 15
Table 4 – Dimensions of button cells. 16
Table 5 – Discharge performance at 20 °C for small prismatic cells and cylindrical cells . 17
Table 6 – Discharge performance at 20 °C for button cells . 18
Table 7 – Discharge performance at 20 °C for batteries . 18
Table 8 – Rated capacity (mAh) compliance test (example) . 19
Table 9 – Discharge performance at –18 °C for small prismatic cells . 19
Table 10 – Discharge performance at –18 °C for cylindrical cells . 19
Table 11 – Discharge performance at –18 °C for button cells . 20
Table 12 – Endurance in cycles for small prismatic cells and cylindrical cells not
dimensionally interchangeable with primary cells . 21
Table 13 – Endurance in cycles for cylindrical cells dimensionally interchangeable with
primary cells . 21
Table 14 – Endurance in cycles for H or X cells . 22
Table 15 – Endurance in cycles for cylindrical X cells . 22
Table 16 – Endurance in cycles for HR or XR cells . 23
Table 17 – Endurance in cycles for button cells . 23
Table 18 – Permanent charge endurance for L, M, J, H or X cylindrical cells. 24

– 4 – IEC 61951-1:2017 © IEC 2017
Table 19 – Permanent charge endurance for button cells . 24
Table 20 – Permanent charge endurance for LT, MT, or HT cylindrical cells . 26
Table 21 – Permanent charge endurance for LU, MU, or HU cylindrical cells . 28
Table 22 – Overcharge at 0 °C . 29
Table 23 – Capacity deterioration due to storage period for cells or batteries . 32
Table 24 – Charge and discharge at +55 °C . 32
Table 25 – Trickle charge acceptance for JT cylindrical cells . 33
Table 26 – Constant discharge currents used for measurement of DC resistance . 34
Table 27 – Sequence of tests for type approval for small prismatic cells . 35
Table 28 – Sequence of tests for type approval for cylindrical cells . 36
Table 29 – Sequence of tests for type approval for button cells . 37
Table 30 – Sequence of tests for type approval for batteries . 38
Table 31 – Recommended test sequence for batch acceptance . 39

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
SECONDARY CELLS AND BATTERIES CONTAINING
ALKALINE OR OTHER NON-ACID ELECTROLYTES –
SECONDARY SEALED CELLS AND BATTERIES
FOR PORTABLE APPLICATIONS –
Part 1: Nickel-cadmium
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.
7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and
members of its technical committees and IEC National Committees for any personal injury, property damage or
other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and
expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC
Publications.
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 61951-1 has been prepared by subcommittee 21A: Secondary
cells and batteries containing alkaline or other non-acid electrolytes, of IEC technical
committee 21: Secondary cells and batteries.
This fourth edition cancels and replaces the third edition published in 2013 of which it
constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
• addition of battery type;
• revision of Figure 3 (6.1.3.1);

– 6 – IEC 61951-1:2017 © IEC 2017
• addition of “Optional pip” note to positive contact;
• changed leader line position from pip to flats of positive contact (B and G).
The text of this standard is based on the following documents:
FDIS Report on voting
21A/622/FDIS 21A/630/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.
A list of all parts of the IEC 61951 series can be found, under the general title Secondary cells
and batteries containing alkaline or other non-acid electrolytes – Secondary sealed cells and
batteries for portable applications, on the IEC website.
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.
SECONDARY CELLS AND BATTERIES CONTAINING
ALKALINE OR OTHER NON-ACID ELECTROLYTES –
SECONDARY SEALED CELLS AND BATTERIES
FOR PORTABLE APPLICATIONS –
Part 1: Nickel-cadmium
1 Scope
This part of IEC 61951 specifies marking, designation, dimensions, tests and requirements for
secondary sealed nickel-cadmium small prismatic, cylindrical and button cells and batteries,
suitable for use in any orientation, for portable applications.
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 60050-482:2004, International Electrotechnical Vocabulary (IEV) – Part 482: Primary and
secondary cells and batteries
IEC 60086-1, Primary batteries – Part 1: General
IEC 60086-2, Primary batteries – Part 2: Physical and electrical specifications
IEC 61959, Secondary cells and batteries containing alkaline or other non-acid electrolytes –
Mechanical tests for sealed portable secondary cells and batteries
IEC 62133-1, Secondary cells and batteries containing alkaline or other non-acid electrolytes
– Safety requirements for portable sealed secondary cells and for batteries made from them,
for use in portable applications – Part 1: Nickel systems
3 Terms and definitions
For the purposes of this document, the terms and definitions given in IEC 60050-482 and the
following apply.
ISO and IEC maintain terminological databases for use in standardization at the following
addresses:
• IEC Electropedia: available at http://www.electropedia.org/
• ISO Online browsing platform: available at http://www.iso.org/obp
3.1
nominal voltage
suitable approximate value of voltage used to designate or identify a cell or a battery
Note 1 to entry: The nominal voltage of a sealed nickel-cadmium rechargeable single cell: 1,2 V.

– 8 – IEC 61951-1:2017 © IEC 2017
Note 2 to entry: The nominal voltage of a battery of n series connected cells is equal to n times the nominal
voltage of a single cell.
[SOURCE: IEC 60050-482:2004, 482-03-31, modified – Addition of Notes 1 and 2 to entry.]
3.2
rated capacity
capacity value of a cell or a battery determined under specified conditions and declared by
the manufacturer
Note 1 to entry: The rated capacity is the quantity of electricity C Ah (ampere-hours) declared by the
manufacturer which a single cell can deliver during a 5 h period when charging, storing and discharging under the
conditions specified in 7.3.2.
Note 2 to entry: The capacity of a battery is the quantity of electricity C Ah (ampere-hours) declared by the
manufacturer which a battery can deliver during a 5 h period, when charged, stored and discharged under the
conditions specified in 7.3.2.
[SOURCE: IEC 60050-482:2004, 482-03-15, modified – Addition of Notes 1 and 2 to entry.]
3.3
small prismatic cell
cell in the form of a rectangular parallelepiped whose width and thickness dimensions are not
more than 25 mm
3.4
cylindrical cell
cell of circular cross-section in which the overall height is equal to, or greater than, the overall
diameter
3.5
button cell
cell of a circular cross-section in which the overall height is less than the overall diameter
3.6
nickel-cadmium cell
cell containing a nickel hydroxide compound for the positive electrode, a cadmium compound
for the negative electrode, and potassium hydroxide or other alkaline solution as electrolyte
Note 1 to entry: Positive electrodes are isolated from negative electrodes by a separator.
3.7
nickel- cadmium battery
assembly of secondary cell(s) as a source of electrical energy characterized by its voltage,
size, terminal arrangement, capacity and rate capability
3.8
sealed cell
cell which remains closed and does not release either gas or liquid when operated within the
limits of charge and temperature specified by the manufacturer
Note 1 to entry: The cell is equipped with a safety device to prevent dangerously high internal pressure.
Note 2 to entry: The cell does not require addition to the electrolyte and is designed to operate during its life in its
original sealed state.
[SOURCE: IEC 60050-482:2004, 482-05-17, modified – The existing note has been developed
into Notes 1 and 2 to entry.]
3.9
portable cell
cell designed mainly for use in an easily hand-carried battery
3.10
battery for portable applications
battery for use in device or appliance which is conveniently hand-carried
4 Parameter measurement tolerances
The overall accuracy of controlled or measured values, relative to the specified or actual
values, shall be within the following tolerances:
a) ±1 % for voltage;
b) ±1 % for current;
c) ±1 % for capacity;
d) ±2 °C for temperature;
e) ±0,1 % for time;
f) ±0,1 mm for dimensions;
g) ±5 % for humidity.
These tolerances comprise the combined accuracy of the measuring instruments, the
measurement techniques used and all other sources of error in the test procedure.
The details of the instrumentation used shall be provided in each report of results.
5 Cell and battery designation and marking
5.1 Cell and battery designation
5.1.1 Small prismatic cells and cylindrical cells
5.1.1.1 General
Sealed nickel-cadmium small prismatic rechargeable single cells and cylindrical rechargeable
single cells shall be designated by a letter L, M, J, H or X which signifies:
• low rate of discharge (L);
• medium rate of discharge (M);
• medium high rate of discharge (J);
• high rate of discharge (H);
• very high rate of discharge (X).
NOTE 1 These cells are typically but not exclusively used for the following discharge rates:
• L up to 0,5 I A;
t
• M up to 3,5 I A;
t
• J up to 5,0 I A;
t
• H up to 7,0 I A;
t
• X up to and above 15 I A.
t
NOTE 2 These currents are expressed as multiples of I A, where I A = C Ah/1 h (see IEC 61434).
t t 5
– 10 – IEC 61951-1:2017 © IEC 2017
When a cell is intended for permanent charge at elevated temperatures, typically higher than
40 °C, a letter "T" is placed after the letter L, M, J, H or X.
When a cell is intended for permanent charge at elevated temperatures, typically higher than
50 °C, a letter "U" is placed after the letter L, M, J, H or X.
A, a letter “R” is placed after the
When a cell is intended for rapid charge, typically at 1,0 I
t
letter L, M, J, H or X.
5.1.1.2 Small prismatic cells
Sealed nickel-cadmium small prismatic rechargeable single cells shall be designated by the
letters “KF” followed by a letter L, M, J, H or X followed by three groups of figures, each one
separated by a solidus:
a) the two figures to the left of the first solidus shall indicate the maximum width specified for
the cell, expressed in millimetres, rounded up to the next whole number;
b) the two figures in the middle shall indicate the maximum thickness specified for the cell,
expressed in millimetres, rounded up to the next whole number;
c) the two figures to the right of the second solidus shall indicate the maximum height
specified for the cell, expressed in millimetres, rounded up to the next whole number.
EXAMPLE KFL 18/07/49 designation identifies a small prismatic cell of low discharge rate capability, with a
maximum width of 18 mm, a maximum thickness of 7 mm and a maximum height of 49 mm.
5.1.1.3 Cylindrical cells
Sealed nickel-cadmium cylindrical rechargeable single cells shall be designated by the letters
“KR” followed by a letter L, M, J, H or X followed by two groups of figures, each one
separated by a solidus:
a) the two figures to the left of the solidus shall indicate the maximum diameter specified for
the cell, expressed in millimetres, rounded up to the next whole number;
b) the two figures to the right of the solidus shall indicate the maximum height specified for
the cell, expressed in millimetres, rounded up to the next whole number.
When a manufacturer designs a cell with dimensions and tolerances which make it
interchangeable with a primary cell, the designation of Table 2 shall also be marked
on the cell.
EXAMPLE 1 KRL 33/62 designation identifies a cylindrical cell of low discharge rate capability, with a maximum
diameter of 33 mm and a maximum height of 61,5 mm.
EXAMPLE 2 KRLT 33/62 designation identifies a cylindrical cell of low discharge rate capability, intended for
permanent charge at elevated temperatures, with a maximum diameter of 33 mm and a maximum height of
61,5 mm.
EXAMPLE 3 KRHR 23/43 designation identifies a cylindrical cell of high discharge rate capability, intended for
rapid charge, with a maximum diameter of 23 mm and a maximum height of 43 mm.
For cells dimensionally interchangeable with primary cells, the following single or double
figures following the letter L, M or R may indicate:
• 20- size D;
• 14- size C;
• 6- size AA;
• 03- size AAA.
EXAMPLE 4 KRMR03 designation identifies a sealed nickel-cadmium cylindrical rechargeable single cell, of
medium discharge rate capability, also intended for rapid charge, dimensionally interchangeable with primary cell
and whose type designation is AAA.

5.1.2 Button cells
Sealed nickel-cadmium button rechargeable single cells shall be designated by the letters
“KB” followed by a letter L, M or H which signifies:
• low rate of discharge (L);
• medium rate of discharge (M);
• high rate of discharge (H).
The group of three letters shall then be followed by two groups of figures separated by a
solidus:
a) the three figures to the left of the solidus shall indicate the maximum diameter specified
for the cell, expressed in tenths of millimetres, rounded up to the next whole number;
b) the three figures to the right of the solidus shall indicate the maximum height specified
for the cell, expressed in tenths of millimetres, rounded up to the next whole number.
EXAMPLE KBL 116/055 designation identifies a button cell of low discharge rate capability, with a maximum
diameter of 11,6 mm and a maximum height of 5,5 mm.
5.1.3 Batteries
Sealed nickel-cadmium rechargeable batteries shall be designated with the following form:
N1 single cell designation -N2
where
N1 is the number of series connected cells in the battery;
N2 is the number of parallel connected cells if 2 or greater (not shown if value is 1).
Sealed nickel-cadmium battery designation will be identified based on single cells within the
series and not the battery as a whole.
• Small prismatic cells in batteries
EXAMPLE 1 2KFL 18/07/49 designation identifies a small prismatic cell of low discharge rate capability, with
a maximum width of 18 mm, a maximum thickness of 7 mm and a maximum height of 49 mm with two series
connected cells.
• Cylindrical cells in batteries
EXAMPLE 2 3KRL 33/62 designation identifies a cylindrical cell of low discharge rate capability, with a
maximum diameter of 33 mm and a maximum height of 61,5 mm with three series connected cells
• Cells interchangeable with primary cells in batteries
EXAMPLE 3 KRMR03-3 designation identifies a sealed nickel-cadmium cylindrical rechargeable single cell, of
medium discharge rate capability, also intended for rapid charge, dimensionally interchangeable with primary
cell whose type designation is AAA with three parallel connected cells.
• Button cells in batteries
EXAMPLE 4 KB116/055-3 designation identifies a button cell, with a maximum diameter of 11,6 mm and a
maximum height of 5,5 mm with three parallel connected cells.
5.2 Cell or battery termination
This standard does not specify cell or battery termination.
5.3 Marking
5.3.1 Small prismatic cells and cylindrical cells
Each jacketed cell supplied without connections shall carry durable markings giving the
following minimum information:
• sealed rechargeable nickel-cadmium or Ni-Cd;

– 12 – IEC 61951-1:2017 © IEC 2017
• rated capacity;
• nominal voltage;
• polarity (+ and –);
• date of manufacture (which may be in code);
• name or identification of manufacturer or supplier;
• mark for promoting useful use of cell resources.
NOTE 1 This mark is applied where a recycling programme is available.
NOTE 2 In general, sealed nickel-cadmium rechargeable single cells with connection tabs need no labels if they
form an integral part of a battery, in which case, the battery itself is marked with the above information.
5.3.2 Button cells
Each button cell supplied without connection shall carry durable markings giving the following
minimum information:
• designation as specified in 5.1;
• polarity (+ and –);
• date of manufacture (which may be in code);
• name or identification of manufacturer or supplier.
5.3.3 Batteries
Each battery shall carry durable markings giving the following minimum information:
• sealed rechargeable nickel- cadmium or Ni-Cd;
• rated capacity;
• nominal voltage;
• date of manufacture (which may be in code).
5.4 Exemption of wording
Each cell or battery shall include minimum information on the label as specified in 5.3.1/ 5.3.3.
Therefore, additional information such as safety cautions should be included in the form of a
manual not on the cell or battery label.
Each cell or battery shall include minimum information on the label as specified in 5.3.1/ 5.3.3.
Therefore, cells or batteries encased in soft or hard plastic with the safety cautions printed on
the outside, should not include caution details on the cell or battery label.
6 Dimensions
6.1 Small prismatic cells and cylindrical cells
6.1.1 General
Figure 1 and Figure 2 show the shape of the cells.

Diameter Thickness
Width
(+) (+)
(–)
(–)
IEC IEC
Figure 1 – Jacketed cylindrical cells Figure 2 – Jacketed small prismatic cells
6.1.2 Small prismatic cells
Table 1 shows the dimensions for jacketed small prismatic cells.
Table 1 – Dimensions of jacketed small prismatic cells
Width Thickness Height
Cell designation
mm mm mm
KF 18/07/41 17,3 6,1 40,2
KF 18/07/49 17,3 6,1 48,2 0
–1,0
KF 18/09/49 17,3 8,3 48,2
–0,7
KF 18/07/68 17,3 6,1 67,3
KF 18/09/68 17,3 –1,0
8,3 67,3
KF 18/11/68 17,3 10,5 67,3
–1,5
KF 18/18/68 17,3 17,3 67,3
–1,0
KF 23/15/68 23,0 14,7 67,3
6.1.3 Cylindrical cells
6.1.3.1 Cells dimensionally interchangeable with primary cells
Table 2 and Figure 3 give the requirements relative to the dimensions for jacketed cylindrical
cells which are dimensionally interchangeable with primary cells.

Height
Height
– 14 – IEC 61951-1:2017 © IEC 2017
Table 2 – Dimensions of jacketed cylindrical cells
dimensionally interchangeable with primary cells
Dimensions
Type
Cell Corresponding
Nominal
mm
designation
designation primary cell
voltage
(reference)
d
A B C D E F G Φ ΦP
a c
V
b
Max Min Min - Max Max Min Min Max Min Max
R03
KR03 AAA 44,5 (43,3) 4,3 0,5 3,8 (2,0) 0,8 10,5 9,5 0,4
LR03
R6
KR6 AA 50,5 (49,2) 7,0 0,5 5,5 (4,2) 1,0 14,5 13,5 0,5
LR6
1,2
R14
KR14 C 50,0 (48,6) 13,0 0,9 7,5 (5,5) 1,5 26,2 24,9 1,0
LR14
R20
KR20 D 61,5 (59,5) 18,0 1,0 9,5 (7,8) 1,5 34,2 32,3 1,0
LR20
NOTE Figures in parentheses are reference values.
a
Cell designations shall be in accordance with the nomenclature rules given in IEC 60086-1.
b
In some countries these cell types are also known as AAA (R 03); AA (R 6); C (R 14); D (R 20).
c
Carbon zinc cells (R) and alkaline primary cells (LR) shall be compliant with the provisions of IEC 60086-2, respectively.
d
There is no specification for the value “D” for sealed nickel-cadmium cylindrical rechargeable single cells interchangeable with
primary cells.
Key
Optional pip
F
A maximum overall height of the cell
B minimum distance between the flats of the positive and the
negative contacts
C minimum outer diameter of the negative flat contact surface
D maximum inner diameter of the negative flat contact surface
E maximum recess of the negative flat contact surface
F maximum diameter of the positive contact within the
specified projection height
G minimum projection of the flat positive contact
D
∅ maximum and minimum diameters of the cell
C
∅P concentricity of the positive contact
ø
IEC
Figure 3 – Jacketed cells dimensionally interchangeable with primary cells
6.1.3.2 Cells not dimensionally interchangeable with primary cells
Table 3 shows the dimensions for jacketed cylindrical cells which are not dimensionally
interchangeable with primary cells.

øP
B
E G
E
A
Table 3 – Dimensions of jacketed cylindrical cells
not dimensionally interchangeable with primary cells
Diameter Height
a
Cell designation
mm mm
KR 8/43 7,8     42,5
KR 11/16 10,5     16,0
KR 11/45 10,5     44,5
KR 12/30 12,0     30,0
KR 15/18 14,5     17,5
KR 15/29 14,5     28,7
KR 15/30 14,5     30,0
KR 15/43 14,5     43,0
KR 15/48 14,5     48,0
–0,7
KR 15/49 14,5     49,0
KR 15/51 14,5     50,5
–1,5
KR 15/65 14,5     65,0
KR 17/18 17,0     17,5
KR 17/29 17,0     28,5
KR 17/43 17,0     43,0
KR 17/50 17,0     50,0
KR 17/66 17,0     66,0
KR 17/67 17,0     67,0
KR 23/27 23,0     26,5
KR 23/34 23,0     34,0
KR 23/43 23,0     43,0
KR 23/50 23,0     50,0
KR 26/31 25,8     31,0
–1,0
KR 26/50 25,8     50,0
KR 33/36 32,1     36,3
–2,0
KR 33/44 33,0     44,0
KR 33/60 33,0 60,0
KR 33/62 33,0     61,5
KR 33/91 33,0     91,0
KR 44/71 43,5 0     71,0
–2,5
–2,5
KR 44/91 43,5     91,0
KR 44/146 43,5    146,0
a
The letters KR to be followed by L, M, J, H or X and T, U and/or R as appropriate (see 5.1.1.3).

6.2 Button cells
Dimensions of cells, shown in Figure 4, are given in Table 4.
Cells shall be constructed as design I or II.
Design I Design II
–
+
d
d
IEC
IEC
NOTE The polarity of design I is not standardized.
Figure 4 – Button cells
Table 4 shows the dimensions for sealed nickel-cadmium button rechargeable single cells.

h
h
– 16 – IEC 61951-1:2017 © IEC 2017
Table 4 – Dimensions of button cells
Diameter, d Height, h
a
Cell designation
mm mm
b
KB 116/055 11,6 5,5
KB 156/048 15,6 4,8
KB 156/061 15,6 6,1
KB 222/050 22,2 5,0
–0,3
KB 229/055 22,9 5,5  0
–0,6
KB 232/030 23,2 3,0
KB 232/055 23,2 5,5
KB 232/067 23,2 6,7
KB 252/064 25,2 6,4
KB 252/077 25,2 7,7
–1,0
KB 252/095 25,2 9,5
–0,4
KB 346/055 34,6 5,5
–0,6
KB 346/098 34,6 9,8
KB 432/081 43,2 8,1
–1,0
KB 505/105 50,5 10,5
a
The letters KB shall be followed by L, M or H as appropriate (see 5.1.2).
b
KB 116/055 may be interchangeable with primary cell R 44.

7 Electrical tests
7.1 General
Charge and discharge currents for the tests in accordance with this Clause 7 and with
Clause 5 shall be based on the rated capacity (C Ah). These currents are expressed as
multiples of I A, where I A = C Ah/1 h.
t t 5
In all tests, except where noted, no leakage of electrolyte in liquid form shall be observed.
7.2 Charging procedure for test purposes
7.2.1 Charging procedure for cell
Prior to charging, the cell shall have been discharged in an ambient temperature
of 20 °C ± 5 °C, at a constant current of 0,2 I A, down to a final voltage of 1,0 V.
t
Unless otherwise stated in this document, the charging procedure for test purposes shall be
carried out in an ambient temperature of 20 °C ± 5 °C and a relative humidity of 65 % ± 20 %,
at a constant current of 0,1 I A for 16 h. The tests shall be performed within 2 months of the
t
manufacture date. Manufacture date is determined by the manufacturer.
...