Note about Electric Blanket Thermostats. The Electric Blankets I have taken apart have no sensor in the blanket itself. Only the controller.
So there really is no closed loop thermal control since the room temperature and the people in bed are not linked. They are linked from the cold room to the blanket, but not the reverse. IE, as the room gets colder, the duty cycle to the blanket increases, but there is no feedback from the warmth under the blanket back to the control. So think of the controller more of as a 0-10 duty cycle adjuster and not much else. Bob, WB4aPR -----Original Message----- From: EV [mailto:[email protected]] On Behalf Of brucedp5 via EV Sent: Friday, February 20, 2015 5:46 PM To: [email protected] Subject: [EVDL] Heating a pack: Cold Charging Lithium Experiences A quick and cheap way to warm a pack is with an inexpensive electric-blanket. These are produced in such high volumes the cost is fairly low, are easy to obtain, and. these come with a thermocouple heat-control, so you will have a little more control over maintaining a steady pre-heating of your pack than a heating source with no thermal control. Years ago (the conversion days), the night before a rally, drivers would pre-warm their PbSO4 packs to 100F by putting an electric-blanket over the top of their wet-cell pack. Since heat rises, if it were possible to place the folded blanket under the pack, that might better utilize the heat provided. {brucedp.150m.com} - electric-vehicle-discussion-list.413529.n4.nabble.com/Cold-Charging-Lithiu m-Experiences-tp4667675p4673895.html Danpatgal Feb 20, 2015; 12:25pm Re: Cold Charging Lithium Experiences Reviving this thread as we're having another very cold stretch here in the Eastern US. My batteries (SE130 CALBs) are still going, but boy do they sag when it's cold like this. It's annoying. I've been charging when my BMS sensors (atop each cell) are over 0C, which they have generally remained over the past few weeks despite the cold (thankfully my garage generally stays above 0C). But, my follow-up question on all this is if the BMS measurement is good enough. For example, I guess there is resistive heat that gets generated upon charge/discharge/shunting that probably make the sensors read higher than the cells themselves. How much, I don't know. Does anybody have any thoughts, experience on this? We've gotten down to -20C with a HIGH today of only -10C ... yet I'm charging. I didn't really want to do it, but I was dragging so much on the road with low SOC%, I had to, or risk having to really limp home. Dan Gallagher http://www.evalbum.com/3854 - -- View this message in context: http://electric-vehicle-discussion-list.413529.n4.nabble.com/Cold-Charging -Lithium-Experiences-tp4667675p4673898.html Sent from the Electric Vehicle Discussion List mailing list archive at Nabble.com. _______________________________________________ UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub http://lists.evdl.org/listinfo.cgi/ev-evdl.org For EV drag racing discussion, please use NEDRA (http://groups.yahoo.com/group/NEDRA) _______________________________________________ UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub http://lists.evdl.org/listinfo.cgi/ev-evdl.org For EV drag racing discussion, please use NEDRA (http://groups.yahoo.com/group/NEDRA)
