For the fun of it, I took a look at my cell phone. It does not have a safety mark on it and the battery pack does not have a safety mark on it. A cell phone that has been through a third party certification would have the proper battery protection, but would one that has not been through the third party certifcaion have the protection? I suspect that the cell phone that I have probably does not use 94V0 plastic to enclose it in a fire enclosure. It may not have gone through the required shipping tests for the Lithium Ion battery.
Most electrical (ok this is an assumption) inspectors would look for a mark on the AC Power supply that came with it and assume the battery device was safe as it was low voltage and not care about it not having a safety mark. As a result cell phone companies (and others) can get away without having safety certifications on their battery (or low voltage) operated products. Another issue is there are a lot of counterfit batteries on the market. So even if you knew who the cell phone company was, you may still not know who made the battery. As for NiCads they are good fire starters as well, but not as good as Lithium. A AA NiCad will push over 80 amps for a significant amount of time (more than a few seconds). 80 Amps is more than enough to ignite an object. Even a mostly discharged NiCad is a good current source. Jim ________________________________ From: emc-p...@ieee.org [mailto:emc-p...@ieee.org] On Behalf Of Haynes, Tim (SELEX) (UK Capability Green) Sent: Wednesday, January 17, 2007 3:53 AM Hi All Are mobile phones designed with a fuse-link in series wit the battery? I have not examined any phone in detail, but the way mine behave makes me believe that the on/off is an electronic switch and that some power is drawn from the battery all the time for running the clock (no pun intended). What protection is there in a phone design if the case when an electronic component fails with a short? Regards ************************ Tim Haynes A1S77 Electromagnetic Engineering Specialist SELEX Sensors and Airborne Systems 300 Capability Green Luton LU1 3PG ( Tel : +44 (0)1582 886239 7 Fax : +44 (0)1582 795863 ) Mob : +44 (0)7703 559 310 (use in UK only !) * E-mail : tim.hay...@selex-sas.com - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. Website: http://www.ieee-pses.org/ To post a message to the list, send your e-mail to emc-p...@ieee.org Instructions: http://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas emcp...@ptcnh.net Mike Cantwell mcantw...@ieee.org For policy questions, send mail to: Jim Bacher: j.bac...@ieee.org David Heald: emc-p...@daveheald.com All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc ______________________________________________________________________ This email has been scanned by the MessageLabs Email Security System. For more information please visit http://www.messagelabs.com/email ______________________________________________________________________ ______________________________________________________________________ This email has been scanned by the MessageLabs Email Security System. For more information please visit http://www.messagelabs.com/email ______________________________________________________________________
