Forgot to mention that battery impedance and internal temperature monitoring are two parametrics oft ignored; and both may explain much weirdness with battery performance.
Brian -----Original Message----- From: Brian O'Connell Sent: Monday, July 30, 2018 10:31 AM To: 'Charlie Blackham'; EMC-PSTC@LISTSERV.IEEE.ORG Subject: RE: Lithium Ion batteries - capacity measurement Not clear what is being asked. Is context safety or purely performance? In any case, data from in vitro tests done with the intended end-use equipment are the 'ultimate' indicator. Should include the full range of rated operating conditions. The SAE, IEEE, IEC, Vulcan Science Academy, and others all have standardized test methods for battery capacity. Test equipment makers (Agilent, et all) have application notes on battery testing. If you use an electronic load to simulate the end-case use, it should use computer-driven profiles - humans tend to make of mess of this stuff where done manually. The nice thing about using electronic loads is that you can have the computer run many "what if?" load profiles. Brian From: Charlie Blackham [mailto:char...@sulisconsultants.com] Sent: Monday, July 30, 2018 9:53 AM To: EMC-PSTC@LISTSERV.IEEE.ORG Subject: [PSES] Lithium Ion batteries - capacity measurement All Client is have a "discussion" with their battery vendor over how capacity of a 3.7V 1000 mAh battery is being measured/demonstrated: Are there any recommendations and/or mandatory requirements for charge/discharge current to be used to demonstrate battery capacity and capacity degradation over multiple cycles? For example: . maximum discharge in the end application normal use is 200 mAh, but the battery manufacturer wants to use 500 mA . one wants to use a "real load", but the other an "electronic load" The different methods appear to be giving different battery voltages for the same remaining capacity, and I would be grateful for any pointers to recommended or best practice Regards Charlie Charlie Blackham Sulis Consultants Ltd Mead House Longwater Road Eversley RG27 0NW UK Tel: +44 (0)7946 624317 Email: char...@sulisconsultants.com Web: www.sulisconsultants.com Registered in England and Wales, number 05466247 - ---------------------------------------------------------------- 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 Attachments are not permitted but the IEEE PSES Online Communities site at http://product-compliance.oc.ieee.org/ can be used for graphics (in well-used formats), large files, etc. 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: Scott Douglas <sdoug...@ieee.org> Mike Cantwell <mcantw...@ieee.org> For policy questions, send mail to: Jim Bacher: <j.bac...@ieee.org> David Heald: <dhe...@gmail.com>
