If power is available to charge the battery then the product could also employ a battery strip heater thermostatically controlled to bring the temp up to minimum.
I have a low voltage low power strip heater on the battery in my listed outdoor gate opener controller. It happens to be a sealed lead acid battery but something similar should work for Li. The heater sits flush on the entire side of the battery, a few mm thick. -Dave -----Original Message----- From: Brian O'Connell [mailto:[email protected]] Sent: Tuesday, April 17, 2018 12:54 PM To: [email protected] Subject: Re: [PSES] EN50131-1 Battery spec vs. Environmental class Depends on Security Grade requirements and where the battery is stored. Li batteries can be used in discharge mode to -20C. Have only done one project for this, where the battery temperature was monitored by the charger, and shut down charge current when outside rated temperature range, but allowed discharge to -20C. Brian From: Amund Westin [mailto:[email protected]] Sent: Monday, April 16, 2018 11:42 PM To: [email protected] Subject: [PSES] EN50131-1 Battery spec vs. Environmental class EN50131-1: Alarm systems - Intrusion and hold-up systems -- Part 1: System requirements >From the standard: Environmental Class II: Indoor General (-10º to +40º) Li-Ion batteries may have this spec: Charging: 0º C to 45º C Discharge/standby: -20ºC to +50º C: As I understand the Li-Ion tech, the batteries should not be charged when temperature is below 0º C and that means it's not possible to qualify for Environmental Class II (-10º to +40º) Indoor General. Unless you monitor the temperature and prevents charging when temperature is under 0º C, but that may lead you into other trouble if temperature remains low over a long period. Any others who has considered the same case and agree? Best regards Amund - ---------------------------------------------------------------- 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 <[email protected]> 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 <[email protected]> Mike Cantwell <[email protected]> For policy questions, send mail to: Jim Bacher: <[email protected]> David Heald: <[email protected]> - ---------------------------------------------------------------- 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 <[email protected]> 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 <[email protected]> Mike Cantwell <[email protected]> For policy questions, send mail to: Jim Bacher: <[email protected]> David Heald: <[email protected]>
