IEC TR 61431:2020

IEC TR 61431 ®
Edition 2.0 2020-09
TECHNICAL
REPORT
Guidelines for the use of monitor systems for lead-acid traction batteries

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IEC TR 61431 ®
Edition 2.0 2020-09
TECHNICAL
REPORT
Guidelines for the use of monitor systems for lead-acid traction batteries

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 29.220.20 ISBN 978-2-8322-8854-2

– 2 – IEC TR 61431:2020  IEC 2020
CONTENTS
FOREWORD . 4
1 Scope . 6
2 Normative references . 6
3 Terms and definitions . 6
4 Desirable characteristics and features . 6
4.1 General . 6
4.2 Physical location of the monitoring device . 6
4.3 State of charge indication or "fuel gauge" . 7
4.4 Battery temperature information . 7
4.5 High battery temperature warning . 7
4.6 Low temperature warning . 7
4.7 Electrolyte level indication . 7
4.8 Electrolyte level maintenance log . 7
4.9 Uniformity of cell properties in a battery . 8
4.10 Battery commissioning date . 8
4.11 Battery configuration . 8
5 Evaluation and analysis . 8
5.1 State of charge indication or "fuel gauge" . 8
5.2 Battery temperature information . 8
5.3 Water consumption . 9
5.4 Uniformity of cell properties . 10
5.5 Electrolyte density . 10
5.6 Capacity throughput . 11
5.7 Battery age . 11
5.8 Battery data sheet . 11
5.9 Communication interfaces . 12
5.10 Ground faults . 12
5.11 Human factors . 12
6 Data monitoring – Recommended list of parameters to be monitored . 13
7 Analysis and evaluation of gathered battery data . 14
7.1 Data flow . 14
7.2 Prediction of residual operational life . 14
Annex A (informative) Example determination of the residual service life of lead-acid
traction batteries . 15
A.1 General . 15
A.2 Lost capacity due to stress factors . 15
A.2.1 Evaluation of the impact of a deep discharge . 15
A.2.2 Evaluation of impact of the battery temperature . 16
A.2.3 Evaluation of the impact of very high discharge currents. 17
A.2.4 Evaluation of the impact of the battery being in idle state . 17
A.2.5 Calculation of the residual capacity. 17
A.2.6 Residual number of cycles . 18

Figure 1 – Potential data flow in a monitor system . 14
Figure A.1 – Example of interrelation between discharge voltages and discharge
currents indicating a deep discharge condition . 16

Table 1 – Residence times and related temperature ranges . 9
Table 2 – Temperature warning levels . 9
Table 3 – Units and value resolution of measured characteristics . 13
Table A.1 – Derating factor due to ageing on standby and idling . 17

– 4 – IEC TR 61431:2020  IEC 2020
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
GUIDELINES FOR THE USE OF MONITOR SYSTEMS
FOR LEAD-ACID TRACTION BATTERIES

FOREWORD
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The main task of IEC technical committees is to prepare International Standards. However, a
technical committee may propose the publication of a technical report when it has collected
data of a different kind from that which is normally published as an International Standard, for
example "state of the art".
IEC TR 61431, which is a Technical Report, has been prepared by IEC technical
committee 21: Secondary cells and batteries.
This second edition cancels and replaces the first edition, published in 1995. This edition
constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) The guidelines have been streamlined in terms of technical content and focussed for
automatic monitoring systems.
The text of this Technical Report is based on the following documents:
Enquiry draft Report on voting
21/1044/DTR 21/1053A/RVDTR
Full information on the voting for the approval of this Technical Report can be found in the
report on voting indicated in the above table.
This document has been drafted in accordance with the ISO/IEC Directives, Part 2.
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under "http://webstore.iec.ch" in the data related to
the specific document. At this date, the document will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
– 6 – IEC TR 61431:2020  IEC 2020
GUIDELINES FOR THE USE OF MONITOR SYSTEMS
FOR LEAD-ACID TRACTION BATTERIES

1 Scope
This document is an informative document relating to aspects of automatic monitor systems
as utilized in lead-acid traction battery applications. It lists the characteristics and features
that need to be monitored and evaluated to properly assess the operative status of a traction
battery. Guidance concerning the accuracy and reliability of the generated information is also
provided.
2 Normative references
There are no normative references in this document.
3 Terms and definitions
No terms and definitions are listed in this document.
...