Hi Amanda, Lots of good ideas from the list.
I have successfully employed an LFP strategy that used seedling mat heaters and electronic temperature controllers. I found that 60-80W of heating with a temp controller would easily keep most smallish battery banks above 50º in unheated battery areas here in Colorado- and it gets cold here too. Like others, I was worried about the reliability of inexpensive heater mats purchased on Amazon, so I started using wifi temperature controllers that could connect to a customer wifi network and push temperature data and alerts to my phone. With many heated lithium systems in the field for years now, I have yet to have a heating system failure, and I’m surprised at how little energy it seems to take to keep batteries at a safe temperature over the winter. There are viable site-engineered options for the situation you describe. Having said all that, I have stopped building battery heater systems due to the appearance on the market of many LFP batteries with pre-engineered cell heating systems. If you have the option to purchase batteries with integral heaters, I’d recommend that as a first choice. Luke Christy Renewable energy consultant NABCEP Certified PV Installation Professional™: Solar Gain Services, LLC PO Box 531 Monte Vista, CO 81144 719.588.3044 [email protected] > On Nov 25, 2025, at 12:58 PM, Amanda Potter via RE-wrenches > <[email protected]> wrote: > > Hello all, > I’ve been reading past posts regarding Battery Box Heating & am trying to > find a simple way to heat an OSB insulated box for various LFP type batteries. > > One Battery Company’s tech support said he uses (at his own home) a 110vac > incandescent bulb plugged in to a thermostat (inexpensive) that lets him heat > between 32 & 50 degrees F. > > I had somebody suggest the same thing with some Christmas lights. > The box & inverter & C.C. are in an un- heated garage on the Canadian border > of NY. ( It can, & does get pretty cold up here.) > > Any suggestions? > > It’s Off-Grid & the owners want their Starlink & Security Cameras to be on > year round. > > Thanks ahead of time! > And, Happy Turkey Day! > > Amanda Potter > Energy Storage Systems > NABCEP PVIP > Adirondack Battery & Solar, LLC > (315) 212-2114 > _______________________________________________ > List sponsored by Redwood Alliance > > Pay optional member dues here: http://re-wrenches.org > > List Address: [email protected] > > Change listserver email address & settings: > http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org > > There are two list archives for searching. When one doesn't work, try the > other: > https://www.mail-archive.com/[email protected]/ > http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org > > List rules & etiquette: > http://www.re-wrenches.org/etiquette.htm > > Check out or update participant bios: > http://www.members.re-wrenches.org >
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