SIST EN 61951-2:2004
(Main)Secondary cells and batteries containing alkaline or other non-acid electrolytes - Portable sealed rechargeable single cells -- Part 2: Nickel-metal hydride
Secondary cells and batteries containing alkaline or other non-acid electrolytes - Portable sealed rechargeable single cells -- Part 2: Nickel-metal hydride
This part of EN 61951 specifies marking, designation, dimensions, tests and require-ments for portable sealed nickel-metal hydride, small prismatic, cylindrical and button rechargeable single cells, suitable for use in any orientation
Akkumulatoren und Batterien mit alkalischem oder anderen nichtsäurehaltigen Elektrolyten - Tragbare wiederaufladbare gasdichte Einzelzellen -- Teil 2: Nickel-Metallhydrid
Accumulateurs alcalins et autres accumulateurs à électrolyte non-acide - Accumulateurs individuels portables étanches -- Partie 2: Nickel-métal hydrure
La présente partie de la EN 61951 spécifie le marquage, la désignation, les dimensions, les essais et les prescriptions applicables aux petits éléments parallélépipédiques, aux éléments cylindriques et aux éléments boutons, individuels, portables, rechargeables, étanches, au nickel-métal hydrure, pouvant être utilisés dans toutes les orientations
Secondary cells and batteries containing alkaline or other non-acid electrolytes - Portable sealed rechargeable single cells - Part 2: Nickel-metal hydride
General Information
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Standards Content (Sample)
SLOVENSKI SIST EN 61951-2:2004
STANDARD
februar 2004
Secondary cells and batteries containing alkaline or other non-acid electrolytes -
Portable sealed rechargeable single cells - Part 2: Nickel-metal hydride
ICS 29.220.30 Referenčna številka
SIST EN 61951-2:2004(en)
© Standard je založil in izdal Slovenski inštitut za standardizacijo. Razmnoževanje ali kopiranje celote ali delov tega dokumenta ni dovoljeno
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EUROPEAN STANDARD EN 61951-2
NORME EUROPÉENNE
EUROPÄISCHE NORM July 2003
ICS 29.220.30 Supersedes EN 61436:1998, EN 61808:2000 & EN 61951-2:2001
English version
Secondary cells and batteries containing
alkaline or other non-acid electrolytes –
Portable sealed rechargeable single cells
Part 2: Nickel-metal hydride
(IEC 61951-2:2003)
Accumulateurs alcalins et autres Akkumulatoren und Batterien mit
accumulateurs à électrolyte non-acide - alkalischem oder anderen
Accumulateurs individuels portables nichtsäurehaltigen Elektrolyten –
étanches Tragbare wiederaufladbare gasdichte
Partie 2: Nickel-métal hydrure Einzelzellen
(CEI 61951-2:2003) Teil 2: Nickel-Metallhydrid
(IEC 61951-2:2003)
This European Standard was approved by CENELEC on 2003-06-01. CENELEC members are bound to
comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European
Standard the status of a national standard without any alteration.
Up-to-date lists and bibliographical references concerning such national standards may be obtained on
application to the Central Secretariat or to any CENELEC member.
This European Standard exists in three official versions (English, French, German). A version in any other
language made by translation under the responsibility of a CENELEC member into its own language and
notified to the Central Secretariat has the same status as the official versions.
CENELEC members are the national electrotechnical committees of Austria, Belgium, Czech Republic,
Denmark, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Luxembourg, Malta,
Netherlands, Norway, Portugal, Slovakia, Spain, Sweden, Switzerland and United Kingdom.
CENELEC
European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung
Central Secretariat: rue de Stassart 35, B - 1050 Brussels
© 2003 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members.
Ref. No. EN 61951-2:2003 E
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EN 61951-2:2003 - 2 -
Foreword
The text of document 21A/374/FDIS, future edition 2 of IEC 61951-2, prepared by SC 21A, Secondary
cells and batteries containing alkaline or other non-acid electrolytes, of IEC TC 21, Secondary cells
and batteries, was submitted to the IEC-CENELEC parallel vote and was approved by CENELEC as
EN 61951-2 on 2003-06-01.
This European Standard supersedes EN 61436:1998, EN 61808:2000 and EN 61951-2:2001.
The following dates were fixed:
– latest date by which the EN has to be implemented
at national level by publication of an identical
national standard or by endorsement (dop) 2004-03-01
– latest date by which the national standards conflicting
with the EN have to be withdrawn (dow) 2006-06-01
Annexes designated "normative" are part of the body of the standard.
In this standard, annex ZA is normative.
Annex ZA has been added by CENELEC.
__________
Endorsement notice
The text of the International Standard IEC 61951-2:2003 was approved by CENELEC as a European
Standard without any modification.
In the official version, for Bibliography, the following note has to be added for the standard indicated:
IEC 61434 NOTE Harmonized as EN 61434:1996 (not modified).
__________
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- 3 - EN 61951-2:2003
Annex ZA
(normative)
Normative references to international publications
with their corresponding European publications
This European Standard incorporates by dated or undated reference, provisions from other
publications. These normative references are cited at the appropriate places in the text and the
publications are listed hereafter. For dated references, subsequent amendments to or revisions of any
of these publications apply to this European Standard only when incorporated in it by amendment or
revision. For undated references the latest edition of the publication referred to applies (including
amendments).
NOTE When an international publication has been modified by common modifications, indicated by (mod), the relevant
EN/HD applies.
Publication Year Title EN/HD Year
1)
IEC 60050-486 - International Electrotechnical - -
Vocabulary (IEV)
Chapter 486: Secondary cells and
batteries
IEC 60051 Series Direct acting indicating analogue EN 60051 Series
electrical measuring instruments and
their accessories
IEC 60086 Series Primary batteries EN 60086 Series
1)
IEC 60410 - Sampling plans and procedures for - -
inspection by attributes
1)
IEC 60485 - Digital electronic d.c. voltmeters and - -
d.c. electronic analogue-to-digital
converters
2)
IEC 61959 - Secondary cells and batteries - -
containing alkaline or other non-acid
electrolytes - Mechanical tests for
sealed portable secondary cells and
batteries
1)
Undated reference.
2)
At draft stage.
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NORME CEI
INTERNATIONALE IEC
61951-2
INTERNATIONAL
Deuxième édition
STANDARD
Second edition
2003-04
Accumulateurs alcalins et autres accumulateurs
à électrolyte non acide –
Accumulateurs individuels portables étanches –
Partie 2:
Nickel-métal hydrure
Secondary cells and batteries containing
alkaline or other non-acid electrolytes –
Portable sealed rechargeable single cells –
Part 2:
Nickel-metal hydride
IEC 2003 Droits de reproduction réservés Copyright - all rights reserved
Aucune partie de cette publication ne peut être reproduite ni No part of this publication may be reproduced or utilized in any
utilisée sous quelque forme que ce soit et par aucun procédé, form or by any means, electronic or mechanical, including
électronique ou mécanique, y compris la photocopie et les photocopying and microfilm, without permission in writing from
microfilms, sans l'accord écrit de l'éditeur. the publisher.
International Electrotechnical Commission, 3, rue de Varembé, PO Box 131, CH-1211 Geneva 20, Switzerland
Telephone: +41 22 919 02 11 Telefax: +41 22 919 03 00 E-mail: inmail@iec.ch Web: www.iec.ch
CODE PRIX
U
Commission Electrotechnique Internationale PRICE CODE
International Electrotechnical Commission
Международная Электротехническая Комиссия
Pour prix, voir catalogue en vigueur
For price, see current catalogue
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61951-2 IEC:2003 – 3 –
CONTENTS
FOREWORD . 7
1 Scope .11
2 Normative references.11
3 Definitions .11
4 Parameter measurement tolerances.13
5 Cell designation and marking.15
5.1 Cell designation.15
5.1.1 Small prismatic cells .15
5.1.2 Cylindrical cells.15
5.1.3 Button cells.17
5.2 Cell termination .17
5.3 Marking .17
5.3.1 Small prismatic cells and cylindrical cells.17
5.3.2 Button cells.19
6 Dimensions.19
6.1 Small prismatic cells and cylindrical cells.19
6.1.1 Small prismatic cells .21
6.1.2 Cylindrical cells.21
6.2 Button cells.23
7 Electrical tests .25
7.1 Charging procedure for test purposes .25
7.2 Discharge performance.25
7.2.1 Discharge performance at 20 °C .25
7.2.2 Discharge performance at 0 °C .27
7.2.3 Discharge performance for rapid charge cells (R cells) .29
7.3 Charge (capacity) retention.29
7.4 Endurance .29
7.4.1 Endurance in cycles.29
7.4.2 Permanent charge endurance .35
7.5 Charge acceptance at constant voltage .37
7.6 Overcharge.39
7.6.1 Small prismatic, L, M, H or X cylindrical, and button cells .39
7.6.2 LT, MT or HT cylindrical cells.39
7.6.3 R cylindrical cells.39
7.7 Safety device operation .41
7.8 Storage.41
7.9 Charge acceptance at +55 °C for LT, MT or HT cylindrical cells.43
7.10 Internal resistance .43
7.10.1 Measurement of the internal a.c. resistance.43
7.10.2 Measurement of the internal d.c. resistance.45
8 Mechanical tests.45
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61951-2 IEC:2003 – 5 –
9 Type approval and batch acceptance.47
9.1 Batch approval .47
9.1.1 Type approval for small prismatic cells and button cells .47
9.1.2 Type approval for cylindrical cells .47
9.2 Batch acceptance .49
Bibliography.53
Figure 1 – Jacketed cylindrical cells .19
Figure 2 – Jacketed small prismatic cells .19
Figure 3 – Button cells .23
Table 1 – Dimensions of jacketed small prismatic cells .21
Table 2 – Cylindrical cells dimensionally interchangeable with primary batteries .21
Table 3 – Dimensions of jacketed cylindrical cells not dimensionally interchangeable
with primary batteries.23
Table 4 – Dimensions of button cells.25
Table 5 – Discharge performance at 20 °C for small prismatic cells and cylindrical cells .27
Table 6 – Discharge performance at 20 °C for button cells .27
Table 7 – Discharge performance at 0 °C for small prismatic cells and cylindrical cells .27
Table 8 – Discharge performance at 0 °C for button cells .29
Table 9 – Endurance in cycles for small prismatic, button and cylindrical cells .31
Table 10 – Endurance in cycles for H or X cells .31
Table 11 – Endurance in cycles for X cells .33
Table 12 – Endurance in cycles for HR or XR cells.33
Table 13 – Permanent charge endurance for L, M, H or X cells .35
Table 14 – Permanent charge endurance for LT, MT or HT cells .37
Table 15 – Overcharge at 0 °C .39
Table 16 – Charge and discharge at +55 °C.43
Table 17 – Constant discharge currents used for measurement of d.c. resistance.45
Table 18 – Sequence of tests for type approval for small prismatic cells and
for button cells .47
Table 19 – Sequence of tests for type approval for cylindrical cells .49
Table 20 – Recommended test sequence for batch acceptance.51
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61951-2 IEC:2003 – 7 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
SECONDARY CELLS AND BATTERIES CONTAINING ALKALINE
OR OTHER NON-ACID ELECTROLYTES –
PORTABLE SEALED RECHARGEABLE SINGLE CELLS –
Part 2: Nickel-metal hydride
FOREWORD
1) The IEC (International Electrotechnical Commission) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of the 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, the IEC publishes International Standards. 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. The 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 the 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 National Committees.
3) The documents produced have the form of recommendations for international use and are published in the form
of standards, technical specifications, technical reports or guides and they are accepted by the National
Committees in that sense.
4) In order to promote international unification, IEC National Committees undertake to apply IEC International
Standards transparently to the maximum extent possible in their national and regional standards. Any
divergence between the IEC Standard and the corresponding national or regional standard shall be clearly
indicated in the latter.
5) The IEC provides no marking procedure to indicate its approval and cannot be rendered responsible for any
equipment declared to be in conformity with one of its standards.
6) Attention is drawn to the possibility that some of the elements of this International Standard may be the subject
of patent rights. The IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 61951-2 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 second edition cancels and replaces the first edition published in 2001 of which it
constitutes a technical revision.
The text of this standard is based on the following documents:
FDIS Report on voting
21A/374/FDIS 21A/380/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.
IEC 61951 series, published under the general title Secondary cells and batteries containing
alkaline or other non-acid electrolytes – Portable sealed rechargeable single cells, consists of
the following parts:
• Part 1: Nickel-cadmium
• Part 2: Nickel-metal hydride.
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61951-2 IEC:2003 – 9 –
The committee has decided that the contents of this publication will remain unchanged until
2008-06. At this date, the publication will be
• reconfirmed;
• withdrawn;
• replaced by a revised edition, or
• amended.
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61951-2 IEC:2003 – 11 –
SECONDARY CELLS AND BATTERIES CONTAINING ALKALINE
OR OTHER NON-ACID ELECTROLYTES –
PORTABLE SEALED RECHARGEABLE SINGLE CELLS –
Part 2: Nickel-metal hydride
1 Scope
This part of IEC 61951 specifies marking, designation, dimensions, tests and requirements for
portable sealed nickel-metal hydride, small prismatic, cylindrical and button rechargeable
single cells, suitable for use in any orientation.
2 Normative references
The following referenced documents are indispensable for the application 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 60050-486, International Electrotechnical Vocabulary – Chapter 486: Secondary cells and
batteries
IEC 60051 (all parts), Direct acting indicating analogue electrical measuring instruments and
their accessories
lEC 60086 (all parts), Primary batteries
IEC 60410, Sampling plans and procedures for inspection by attributes
IEC 60485, Digital electronic d.c. voltmeters and d.c. electronic analogue-to-digital converters
IEC 61959, Secondary cells and batteries containing alkaline or other non-acid electrolytes –
1
Mechanical tests for sealed portable secondary cells and batteries
3 Definitions
For the purposes of this document, the definitions contained in IEC 60050-486 and the
following apply:
3.3.1
small prismatic cell
cell in the form of a rectangular parallelepiped whose width and thickness dimensions are not
more than 25 mm
———————
1
To be published.
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61951-2 IEC:2003 – 13 –
3.3.2
cylindrical cell
cell of circular cross-section in which the overall height is equal to, or greater than the overall
diameter
3.3.3
button cell
cell of circular cross-section in which the overall height is less than the overall diameter
3.3.4
nickel-metal hydride cell
cell containing a nickel hydroxide compound for the positive electrode and a hydrogen
absorbing alloy for the negative electrode
3.3.5
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. The cell is equipped with a
safety device to prevent dangerously high internal pressure. The cell does not require addition
to the electrolyte and is designed to operate during its life in its original sealed state
NOTE The nickel-metal hydride cell, however, may release gas towards the end of its life due to the accumulation
of hydrogen in the cell.
3.3.6
nominal voltage
nominal voltage of a sealed nickel-metal hydride rechargeable single cell: 1,2 V
3.3.7
portable cell
cell designed mainly for use in an easily hand-carried battery
3.3.8
rated capacity
quantity of electricity C Ah (ampere-hours) declared by the manufacturer which a single cell
5
can deliver during a 5 h period when charging, storing and discharging under the conditions
specified in 7.2.1
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.
These tolerances comprise the combined accuracy of the measuring instruments, the
measurement techniques used and all other sources of error in the test procedure.
For assistance in selecting instrumentation, see the IEC 60051 series for analogue
instruments and IEC 60485 for digital instruments. The details of the instrumentation used
shall be provided in each report of results.
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61951-2 IEC:2003 – 15 –
5 Cell designation and marking
5.1 Cell designation
5.1.1 Small prismatic cells
Sealed nickel-metal hydride small prismatic rechargeable single cells shall be designated by
the letters "HF" 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 HF 18/07/49 designation identifies a small prismatic cell, with a maximum width of
18 mm, a maximum thickness of 7 mm and a maximum height of 49 mm.
5.1.2 Cylindrical cells
Sealed nickel-metal hydride cylindrical rechargeable single cells shall be designated by the
letters "HR" followed by a letter L, M, H or X which signifies:
• low rate of discharge (L);
• medium rate of discharge (M);
• high rate of discharge (H);
• very high rate of discharge (X).
NOTE 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
• H up to 7,0 I A;
t
• X up to and above 7,0 I A.
t
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, 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, H or X.
The group of three (or four) letters shall then be followed by two groups of figures 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 battery, the designation of Table 2 shall also be marked
on the cell.
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61951-2 IEC:2003 – 17 –
EXAMPLE 1 HRL 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 HRLT 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 HRXR 23/43 designation identifies a cylindrical cell of very high discharge rate
capability, which is also intended for rapid charge, with a maximum diameter of 23 mm and a
maximum height of 43 mm.
5.1.3 Button cells
Sealed nickel-metal hydride button rechargeable single cells shall be designated by the letters
"HB" 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 HB 116/054 designation identifies a button cell, with a maximum diameter of 11,6
mm and a maximum height of 5,4 mm.
5.2 Cell termination
This standard does not specify cell 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-metal hydride or Ni-MH;
• designation as specified in 5.1 (in addition, it is permissible for a manufacturer to use his
own type designation);
• rated capacity;
• nominal voltage;
• recommended charge rate and time or permanent charge current for "T" cells;
• polarity;
• date of manufacture (which may be in code);
• name or identification of manufacturer or supplier.
NOTE In general, sealed nickel-metal hydride 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.
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61951-2 IEC:2003 – 19 –
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;
• date of manufacture (which may be in code);
• name or identification of manufacturer or supplier.
6 Dimensions
6.1 Small prismatic cells and cylindrical cells
Thickness
Width
Diameter
(+) (+)
(–)
(–)
IEC 1140/03 IEC 1141/03
Figure 1 – Jacketed cylindrical cells Figure 2 – Jacketed small
prismatic cells
Height
Height
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61951-2 IEC:2003 – 21 –
6.1.1 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
HF 15/08/49 14,5 7,4 48,2
HF 15/09/49 14,5 8,3 48,2
HF 18/07/36 17,3 6,1 35,7 0
0 –1,0
HF 18/07/49 17,3 6,1 48,2
–0,7
HF 18/09/49 17,3 8,3 48,2
0
HF 18/07/68 17,3 6,1 67,3
–1,0
HF 18/11/68 17,3 10,7 67,3
HF 18/18/68 17,3 17,3 67,3 0
0 –1,5
HF 23/11/68 22,7 10,7 67,3
–1,0
HF 23/15/68 22,7 14,5 67,3
6.1.2 Cylindrical cells
6.1.2.1 Cells dimensionally interchangeable with primary batteries
Table 2 gives the requirements relative to the dimensions for jacketed cylindrical cells which
are dimensionally interchangeable with primary batteries.
Table 2 – Cylindrical cells dimensionally interchangeable with primary batteries
Corresponding
a b
Cell designation primary battery Dimensions
IEC 60086
HR 03 R 03 All dimensions shall be
in accordance
HR 6 R 6 with IEC 60086-2
HR 14 R 14
HR 20 R 20
a
Cell designations shall be in accordance with the nomenclature rules given in IEC 60086-1.
b
In some countries these are also known as AAA (R 03); AA (R 6); C (R 14); D (R 20).
6.1.2.2 Cells not dimensionally interchangeable with primary batteries
Table 3 shows the dimensions for jacketed cylindrical cells which are not dimensionally
interchangeable with primary batteries.
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61951-2 IEC:2003 – 23 –
Table 3 – Dimensions of jacketed cylindrical cells not dimensionally
interchangeable with primary batteries
Diameter Height
a
Cell designation
mm mm
HR 11/45 10,5 44,5
HR 11/51 10,5 50,5
HR 11/67 10,5 67,0
HR 15/43 14,5 43,0
0
HR 15/49 14,5 49,0
–1,5
0
HR 15/51 14,5 –0,7 50,5
HR 17/29 17,0 28,5
HR 17/43 17,0 43,0
HR 17/50 17,0 50,0
0
–2,0
HR 17/67 17,0 67,0
HR 23/34 23,0 34,0
0
...
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