The standard requires that the battery charging circuit must terminate the charge if the temperature of the cell (measured as per the cell manufacturer’s instructions, usually a thermocouple on the negative terminal IIRC) exceeds the manufacturers specifications.
If the cells are in a thermally homogeneous part of the equipment then perhaps sensing just one cell could be considered adequate. Temperature testing would give you this answer. What happens if the internal resistance of the cell goes up, or the design is non thermally homogenous? In this case two thermistors might be sensible. If your charging circuit only has one thermistor trip input then perhaps you could use a comparator of some kind to monitor temperature of the second cell. All the best James James Pawson Managing Director & EMC Problem Solver Unit 3 Compliance Ltd EMC : Environmental & Vibration : Electrical Safety : CE & UKCA : Consultancy <http://www.unit3compliance.co.uk/> www.unit3compliance.co.uk | <mailto:ja...@unit3compliance.co.uk> ja...@unit3compliance.co.uk +44(0)1274 911747 | +44(0)7811 139957 2 Wellington Business Park, New Lane, Bradford, BD4 8AL Registered in England and Wales # 10574298 Office hours: Every morning my full attention is on consultancy, testing, and troubleshooting activities for our customers’ projects. I’m contactable between 1300h to 1730h from Monday to Friday. For inquiries, bookings, and testing updates please send us an email on he...@unit3compliance.co.uk <mailto:he...@unit3compliance.co.uk> or call 01274 911747. Our lead times for testing and consultancy are typically 4-5 weeks. From: sgbrody <sgbr...@comcast.net> Sent: Friday, April 14, 2023 10:48 PM To: EMC-PSTC@LISTSERV.IEEE.ORG Subject: [PSES] 62368 Battery question I have a product that uses 2 rechargeable C cell LiPo batteries that are not in a single package. Does or should each have a monitored NTC? I believe yes bit seeking other thoughts. Thanks, Sent from my T-Mobile 5G Device - ---------------------------------------------------------------- This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to <emc-p...@ieee.org <mailto:emc-p...@ieee.org> > All emc-pstc postings are archived and searchable on the web at: http://www.ieee-pses.org/emc-pstc.html Website: http://www.ieee-pses.org/ Instructions: http://www.ieee-pses.org/list.html (including how to unsubscribe) <http://www.ieee-pses.org/list.html> List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Mike Cantwell <mcantw...@ieee.org <mailto:mcantw...@ieee.org> > For policy questions, send mail to: Jim Bacher <j.bac...@ieee.org <mailto:j.bac...@ieee.org> > David Heald <dhe...@gmail.com <mailto:dhe...@gmail.com> > _____ To unsubscribe from the EMC-PSTC list, click the following link: https://listserv.ieee.org/cgi-bin/wa?SUBED1=EMC-PSTC <https://listserv.ieee.org/cgi-bin/wa?SUBED1=EMC-PSTC&A=1> &A=1 - ---------------------------------------------------------------- This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to <emc-p...@ieee.org> All emc-pstc postings are archived and searchable on the web at: http://www.ieee-pses.org/emc-pstc.html Website: http://www.ieee-pses.org/ Instructions: http://www.ieee-pses.org/list.html (including how to unsubscribe) List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Mike Cantwell <mcantw...@ieee.org> For policy questions, send mail to: Jim Bacher: <j.bac...@ieee.org> David Heald: <dhe...@gmail.com> _________________________________________________ To unsubscribe from the EMC-PSTC list, click the following link: https://listserv.ieee.org/cgi-bin/wa?SUBED1=EMC-PSTC&A=1
