A trivially simple, non-costly pressure release mechanism is a piece of .020" or 0.040" GoreTex sheet covering a vent hole (about half an inch diameter). This will be totally waterproof to >4 meters depth (I designed a patented hydrostatic release mechanism used on a popular shipboard EPIRB rescue beacon that uses this very principle). The GoreTex is impermeable to water at reasonable pressures, but easily passes gasses, thus as far as the water is concerned, the housing is sealed; but the battery can vent easily.
Bob Wilson TIR Systems Ltd. Vancouver. -----Original Message----- From: McKinney, Alex [mailto:mckinne...@ems-t.com] Sent: March 14, 2002 11:51 AM To: IEEE EMC-PSTC Forum (E-mail) Subject: IP67 Water Ingress Testing All, We are currently working on a new handheld product that will be tested for IP67 Water Ingress (1 meter submersion for 30 minutes) and we are trying to determine the safety impact of not including the lithium ion battery pack as part of this rating. This product will be UL60950 Listed. One question that has also been asked of me is whether this battery pack needs to be vented. A few lithium ion cell manufactures whom I have researched on this say that the pack should definitely be vented. If vented then the IP67 rating on the battery pack is definitely out of the question without designing some costly pressure release mechanism. I guess my ultimate question is, how safe is a lithium ion battery pack if water is introduced in to the circuit? Any help is greatly appreciated. Regards, Alex McKinney Safety Engineer LXE, Inc. Tel: 770-447-4224 x3606 Fax: 770-447-6928 ------------------------------------------- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://ieeepstc.mindcruiser.com/ Click on "browse" and then "emc-pstc mailing list" ------------------------------------------- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://ieeepstc.mindcruiser.com/ Click on "browse" and then "emc-pstc mailing list"
