prEN IEC 61951-1:2026

SLOVENSKI STANDARD
01-marec-2026
Sekundarni členi in baterije z alkalnimi ali drugimi nekislinskimi elektroliti -
Sekundarni hermetični členi in baterije za prenosne naprave - 1. del: Nikelj-kadmij
Secondary cells and batteries containing alkaline or other non-acid electrolytes -
Secondary sealed cells and batteries for portable applications - Part 1: Nickel-Cadmium
Sekundärzellen und -batterien mit alkalischen oder anderen nichtsäurehaltigen
Elektrolyten - Tragbare wiederaufladbare gasdichte Zellen und Batterien - Teil 1: Nickel-
Cadmium
Accumulateurs alcalins et autres accumulateurs à électrolyte non-acide - Accumulateurs
étanches pour applications portables - Partie 1: Nickel-Cadmium
Ta slovenski standard je istoveten z: prEN IEC 61951-1:2026
ICS:
29.220.30 Alkalni sekundarni členi in Alkaline secondary cells and
baterije batteries
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

21A/961/CDV
COMMITTEE DRAFT FOR VOTE (CDV)
PROJECT NUMBER:
IEC 61951-1 ED5
DATE OF CIRCULATION: CLOSING DATE FOR VOTING:
2026-01-30 2026-04-24
SUPERSEDES DOCUMENTS:
21A/920/CD, 21A/950A/CC
IEC SC 21A : SECONDARY CELLS AND BATTERIES CONTAINING ALKALINE OR OTHER NON-ACID ELECTROLYTES
SECRETARIAT: SECRETARY:
France Mr Jean-Marie Bodet
OF INTEREST TO THE FOLLOWING COMMITTEES: HORIZONTAL FUNCTION(S):

TC 35
ASPECTS CONCERNED:
SUBMITTED FOR CENELEC PARALLEL VOTING NOT SUBMITTED FOR CENELEC PARALLEL VOTING
Attention IEC-CENELEC parallel voting
The attention of IEC National Committees, members of
CENELEC, is drawn to the fact that this Committee Draft
for Vote (CDV) is submitted for parallel voting.
The CENELEC members are invited to vote through the
CENELEC online voting system.
This document is still under study and subject to change. It should not be used for reference purposes.
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Recipients of this document are invited to submit, with their comments, notification of any relevant “In Some
Countries” clauses to be included should this proposal proceed. Recipients are reminded that the CDV stage is
the final stage for submitting ISC clauses. (SEE AC/22/2007 OR NEW GUIDANCE DOC).

TITLE:
Secondary cells and batteries containing alkaline or other non-acid electrolytes - Secondary
sealed cells and batteries for portable applications - Part 1: Nickel-Cadmium

PROPOSED STABILITY DATE: 2027
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IEC CDV 61951-1 © IEC 2026
CONTENTS
Contact . 3
CONTENTS . 4
FOREWORD . 7
INTRODUCTION . 9
1 Scope . 10
2 Normative references . 10
3 Terms and definitions . 10
4 Parameter measurement tolerances . 12
5 Cell and battery designation and marking . 12
5.1 Cell and battery designation . 12
5.1.1 Small prismatic cells and cylindrical cells . 12
5.1.2 Button cells . 14
5.1.3 Batteries . 14
5.2 Cell or battery termination . 15
5.3 Marking . 15
5.3.1 Small prismatic cells and cylindrical cells . 15
5.3.2 Button cells . 15
5.3.3 Batteries . 15
5.4 Exemption of wording . 16
6 Dimensions . 16
6.1 Small prismatic cells and cylindrical cells . 16
6.1.1 General . 16
6.1.2 Small prismatic cells . 17
6.1.3 Cylindrical cells . 17
6.2 Button cells . 20
7 Electrical tests . 21
7.1 General . 21
7.2 Charging procedure for test purposes . 21
7.2.1 Charging procedure for cell . 21
7.2.2 Charging procedure for battery . 22
7.3 Discharge performance . 22
7.3.1 General . 22
7.3.2 Discharge performance at 20 °C . 22
7.3.3 Discharge performance at -18 °C . 24
7.3.4 Discharge performance for R cylindrical cells (rapid charge cells) . 25
7.4 Charge (capacity) retention . 26
7.5 Endurance . 26
7.5.1 Endurance in cycles . 26
7.5.2 Permanent charge endurance . 29
7.6 Charge acceptance at constant voltage. 34
7.7 Overcharge . 34
7.7.1 Small prismatic cells . 34
7.7.2 L, M, H or X cylindrical and button cells . 35
7.7.3 LT/LU, MT/MU or HT/HU cylindrical cells . 35
7.7.4 J cylindrical cells . 35
7.7.5 JT cylindrical cells . 36
IEC CDV 61951-1 © IEC 2026
7.7.6 R cylindrical cells (rapid charge cells) . 36
7.8 Button cells or batteries storage, small prismatic cells or batteries storage,
cylindrical cells or batteries storage . 36
7.9 Charge acceptance at +55 °C for LT, MT or HT cylindrical cells . 37
7.10 Trickle charge acceptance for JT cylindrical cells . 38
7.11 Internal resistance . 38
7.11.1 General . 38
7.11.2 Measurement of the internal AC resistance (Impedance) . 39
7.11.3 Measurement of the internal DC resistance . 39
8 Mechanical tests . 40
9 Safety requirements . 40
10 Type approval and batch acceptance . 40
10.1 General . 40
10.2 Type approval . 40
10.2.1 Type approval for small prismatic cells . 40
10.2.2 Type approval for cylindrical and button cells . 41
10.2.3 Type approval for batteries . 45
10.3 Batch acceptance . 45
Bibliography . 47

Figure 1 – Jacketed cylindrical cells . 16
Figure 2 – Jacketed small prismatic cells . 17
Figure 3 – Jacketed cells dimensionally interchangeable with primary cells . 19
Figure 4 – Button cells . 21

Table 1 – Dimensions of jacketed small prismatic cells . 17
Table 2 – Dimensions of jacketed cylindrical cells dimensionally interchangeable with
primary cells . 18
Table 3 – An example of dimensions of jacketed cylindrical cells not dimensionally
interchangeable with primary cells . 19
Table 4 – Dimensions of button cells . 21
Table 5 – Discharge performance at 20 °C for small prismatic cells . 22
Table 6 – Discharge performance at 20 °C for cylindrical cells . 23
Table 7 – Discharge performance at 20 °C for button cells . 23
Table 8 – Discharge performance at 20 °C for batteries . 24
Table 9 – Rated capacity (mAh) compliance test (example) . 24
Table 10 – Discharge performance at -18 °C for small prismatic cells . 25
Table 11 – Discharge performance at -18 °C for cylindrical cells . 25
Table 12 – Discharge performance at -18 °C for button cells . 25
Table 13 – Endurance in cycles for small prismatic cells and cylindrical cells not
dimensionally interchangeable with primary cells . 26
Table 14 – Endurance in cycles for cylindrical cells dimensionally interchangeable with
primary cells . 27
Table 15 – Endurance in cycles for H or X cells . 28
Table 16 – Endurance in cycles for cylindrical X cells . 28
Table 17 – Endurance in cycles for HR or XR cells . 29
IEC CDV 61951-1 © IEC 2026
Table 18 – Endurance in cycles for button cells . 29
Table 19 – Permanent charge endurance for L, M, J, H or X cylindrical cells . 30
Table 20 – Permanent charge endurance for L, M, or H button cells . 30
Table 21 – Permanent charge endurance for LT, MT, or HT cylindrical cells . 31
Table 22 – Permanent charge endurance for LU, MU, or HU cylindrical cells . 33
Table 23 – Overcharge for LT/LU, MT/MU, or HT/HU cylindrical cells at 0 °C . 35
Table 24 – Capacity deterioration due to storage period for cells or batteries. 37
Table 25 – Charge and discharge at +55 °C . 38
Table 26 – Trickle charge acceptance for JT cylindrical cells . 38
Table 27 – Constant discharge currents used for measurement of DC resistance . 40
Table 28 – Sequence of tests for type approval for small prismatic cells . 41
Table 29 – Sequence of tests for type approval for cylindrical cells . 42
Table 30 – Sequence of tests for type approval for button cells. 42
Table 31 – Sequence of tests for type approval for cylindrical cells (Not assume
permanent charge usage) . 43
Table 32 – Sequence of tests for type approval for button cells (Not assume permanent
charge usage) . 44
Table 33 – Sequence of tests for type approval for batteries . 45
Table 34 – Recommended test sequence for batch acceptance . 46

IEC CDV 61951-1 © IEC 2026
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,
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2) The formal decisions or agreements of IEC on technical matters express, as nearly as
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3) IEC Publications have the form of recommendations for international use and are accepted
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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
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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) IEC draws attention to the possibility that the implementation of this document may involve
the use of (a) patent(s). IEC takes no position concerning the evidence, validity or applicability
IEC CDV 61951-1 © IEC 2026
of any claimed patent rights in respect thereof. As of the date of publication of this document,
IEC [had/had not] received notice of (a) patent(s), which may be required to implement this
document. However, implementers are cautioned that this may not represent the latest
information, which may be obtained from the patent database available at https://patents.iec.ch.
IEC shall not be held responsible for identifying any or all such patent rights.
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. It is an International Standard.
This fifth edition cancels and replaces the fourth edition published in 2017 and its amendment
1 published in 2022 of which it constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
– addition of application examples as performance reference test in scope;
– addition of manufacture period indication options;
– revision of dimensions of jacketed cylindrical cells dimensionally interchangeable with
primary cells (ϕP: reference value);
– addition of criteria of R cylindrical cells in charge retention (7.4);
– revision of charge endurance test objects (7.5.2.1);
– revision of type approval test table (10.2) which harmonized with revision of charge
endurance test objects.
The text of this International Standard is based on the following documents:
Draft Report on voting
21A/XX/FDIS 21A/XX/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 [change
language if necessary].
This document was drafted in accordance with ISO/IEC Directives, Part 2, and developed in
accordance with ISO/IEC Directives, Part 1 and ISO/IEC Directives, IEC Supplement, available
at www.iec.ch/members_experts/refdocs. The main document types developed by IEC are
described in greater detail at www.iec.ch/publications.
A list of all parts 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 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.
IEC CDV 61951-1 © IEC 2026
INTRODUCTION
Note from IEC: The following items were listed in the bibliography but not cited in the text.
Please find a suitable place to cite them to justify their inclusion in the bibliography:
IEC 60051 (all parts), Direct acting indicating analogue electrical measuring instruments and
their accessoriesIEC 60051 (all parts) [1]
IEC 60086 (all parts), Primary batteriesIEC 60086 (all parts) [2]
IEC 60485, Digital electronic d.c. voltmeters and d.c. electronic analogue-to-digital
convertorsIEC 60485 [3]
___________
This document was withdrawn.
IEC CDV 61951-1 © IEC 2026
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
which are conveniently hand-carried, suitable use for portable applications.
Examples of portable applications are remote controllers, flashlights, toys, electric toothbrush,
power tools and similar equipment.
This standard also covers portable cells and batteries for the following applications as a
performance reference standard (specific standards or regulations take precedence):
a) Fixed application: in-vehicle accessories, emergency lights and similar equipment, and
b) Personal mobility application: mobility scooters or electric bicycles that are not required to
be registered for use on the road, and similar equipment.
NOTE The cell is not limited to specific products indicated in examples, if there is agreement between supplier and
purchaser.
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
IEC 62902, Secondary cells and batteries - Marking symbols for identification of their chemistry
3 Terms and definitions
For the purposes of this document, the terms and definitions given in IEC 60050-482:2004 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
IEC CDV 61951-1 © IEC 2026
Note 1 to entry: The nominal voltage of a nickel-cadmium rechargeable single cell: 1,2 V.
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 NOTE 1 and NOTE 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 NOTE 1 and NOTE 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 NOTE 1 and NOTE 2 to entry.]
IEC CDV 61951-1 © IEC 2026
3.9
trickle charge
method of charge applied to a battery wherein the state of charge is maintained by a continuous,
long term, regulated small electric current
Note 1 to entry: The trickle charge compensates self-discharge effects and maintains the battery in an
approximately fully charged state.
Note 2 to entry: The trickle charge is not suitable for cells and batteries that are designed with overcharge
protection.
Note 3 to entry: The trickle charge is performed with the cell or battery disconnected from the load.
[SOURCE: IEC 60050-482:2004, 482-05-17, modified - Replace secondary battery type not
suitable for trickle charge to cells and batteries that are designed with overcharge protection
and add NOTE 3 to entry.]
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 according to discharge rate characteristics 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
IEC CDV 61951-1 © IEC 2026
– J up to 5,0 I A;
t
– H up to 7,0 I A;
t
– X over 7,0 I A.
t
NOTE 2 These currents are expressed as multiples of I A, where
t
𝐼 A=𝐶 Ah/1 h (see IEC 61434 [4]).
t 5
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.
When a cell is intended for rapid charge, typically at 1,0 I A, a letter "R" is placed after the
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, and where applicable, followed by a letter T,U
and/or R, 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, and where applicable, followed by a letter T,U and/or
R, 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.
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, typically higher than 40 °C, 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 typically at 1,0 I A, with a maximum diameter of 23 mm and a maximum height of 43 mm.
t
For cells dimensionally interchangeable with primary cells, the following single or double figures
following the letter L or M, J, H or X, and where applicable, following the letter R may indicate:
– 20- size D;
– 14- size C;
– 6- size AA;
– 03- size AAA.
IEC CDV 61951-1 © IEC 2026
For the purpose of this explanation, an example is given below.
EXAMPLE 4 KRMR03 designation identifies a sealed nickel-cadmium cylindrical rechargeable single cell, of
medium discharge rate capability, also intended for rapid charge typically at 1,0 I A, dimensionally interchangeable
t
with primary cell and whose type designation is AAA.
When a manufacturer designs a cell with dimensions and tolerances which make it
interchangeable with a primary cell, the designations in Table 2 shall also be marked on the
cell.
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 (1)
where
N1 is the number of series connected cells greater than or equal to 2 in the battery;
N2 is the number of parallel connected cells greater than or equal to 2 in the battery.
N1 and/or N2 is not shown if its 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 typically at 1.0 I A, dimensionally interchangeable
t
with primary cell whose type designation is AAA with three parallel connected cells.
IEC CDV 61951-1 © IEC 2026
– Button cells in batteries
EXAMPLE 4 KBL116/055-3 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 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, nickel-cadmium or Ni-Cd;
– rated capacity;
– nominal voltage;
– polarity (+ and -);
– date of manufacture (which may be in code);
– name, identification, or registered trademark 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.
NOTE 3 If manufacturer and purchaser agree to omit date indication from date of manufacture, they can indicate
year and month or week of manufacture on the cell. The method of indicating the manufacturing period may be
determined by the agreement. The first date rule of month or week is based on ISO 8601.
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, identification, or registered trademark of manufacturer or supplier.
NOTE If manufacturer and purchaser agree to omit date indication from date of manufacture, they can indicate year
and month or week of manufacture on the cell. The method of indicating the manufacturing period may be determined
by the agreement. The first date rule of month or week is based on ISO 8601.
5.3.3 Batteries
Each battery shall carry durable markings giving the following minimum information:
– sealed rechargeable nickel-cadmium battery, nickel-cadmium battery or Ni-Cd;
– rated capacity;
– nominal voltage;
– date of manufacture (which may be in code);
– marking symbols (identification of the chemistry according to IEC 62902).
NOTE If manufacturer and purchaser agree to omit date indication from date of manufacture, they can indicate year
and month or week of manufacture on the battery. The method of indicating the manufacturing period may be
determined by the agreement. The first date rule of month or week is based on ISO 8601.
IEC CDV 61951-1 © IEC 2026
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.
In addition, 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 jacketed cells.

Figure 1 – Jacketed cylindrical cells
IEC CDV 61951-1 © IEC 2026
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
a Width Tolerance Thickness Tolerance Height Tolerance
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 (4)
−1,0
KF 18/09/49 17,3 8,3 (3) 48,2
−7,0
KF 18/07/68 17,3 6,1 67,3
(2)
−1,0
KF 18/09/68 17,3 8,3 67,3
KF 18/11/68 17,3 10,5 67,3 (5)
−1,5
KF 18/18/68 17,3 17,3 67,3
(6)
−1,0
KF 23/15/68 23,0 14,7 67,3
a
Cell designations shall be in accordance with the nomenclature rules given in 5.1.1.2.
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.
IEC CDV 61951-1 © IEC 2026
Table 2 – Dimensions of jacketed cylindrical cells dimensionally interchangeable with
primary cells
Cell Type Correspon Nomi Dimensions
designati designati ding nal
mm
a on primary voltag
on
(referenc c e V
cell A B C D E F G ϕ ϕP
b
e)
d
Ma Mi Mi - Ma Ma Mi Mi Ma Mi Ma
x n n x x n n x n x
KR03 AAA R03 1,2 44, 43, 4,3 0,5 3,8 2, 0, 10, 9,8 -

5 5 0 8 5
LR03
KR6 AA R6 50, 49, 7,0 0,5 5,5 4, 1, 14, 13, -

5 5 2 0 5 7
LR6
KR14 C R14 50, 48, 13, 0,9 7,5 5, 1, 26, 24, -

0 6 0 5 5 2 9
LR14
KR20 D R20 61, 59, 18, 1,0 9,5 7, 1, 34, 32, -

5 5 0 8 5 2 3
LR20
NOTE Figures in parentheses are reference values.
a
Cell designations shall be in accordance with the nomenclature rules given in 5.1.1.3.
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.
IEC CDV 61951-1 © IEC 2026
concentricity of the positive contact

Key
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
∅ maximum and minimum diameters of the cell
∅P concentricity of the positive contact
Figure 3 – Jacketed cells dimensionally interchangeable with primary cells
6.1.3.2 Cells not dimensionally interchangeable with primary cells
There is no dimension requirement for cells not dimensionally interchangeable with primary
cells. Table 3 shows an example of the dimensions for jacketed cylindrical cells which are not
dimensionally interchangeable with primary cells.
T
...