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LiFePO4 heating pad for cold temperatures

@8milimeter, I wish you had posted larger pictures. I would have liked to zoom in on your build.

The folks I talked to on the phone, that sold me my kit, didn't say it outright but I'm pretty sure they are the OEM supplier for the Battleborn warming pads. The components I see in your pictures look exactly like the ones I have.
 
Are you not compressing your cells? The compression frame limited me to what sides of the battery I could put warming pads on. I didn't think that putting the warming pad between the frame and the battery would be good for the pad.
 
Now that they are installed its hard to measure. They are about 1/4 higher then the edge of the lower battery case. I would say 8.25 to 8.5".
They wrap around 3 sides plus 6". That's 7 + 12.75 + 7 + 6. So approximately 32.75". There web site says 8.5 x 29.5.

Of course they just put there new heated batteries on there web site. Would have been much easier and cheaper if I had waited.
 
Are you not compressing your cells? The compression frame limited me to what sides of the battery I could put warming pads on. I didn't think that putting the warming pad between the frame and the battery would be good for the pad.
I don't think so, they are not tight in my box. The battery ends have a protrusion for the strap 1/4". It touches the foam, but there is plenty of room 1/4" for the pad. Also the foam is soft enough to allow for some expansion. Side to side there is space between each battery.
 
I don't think so, they are not tight in my box. The battery ends have a protrusion for the strap 1/4". It touches the foam, but there is plenty of room 1/4" for the pad. Also the foam is soft enough to allow for some expansion. Side to side there is space between each battery.

Sorry for the confusion. That post was intended for user oldtoad. Those of us creating our batteries from cells need to compress the cell pack for best results.
 
Wanted to mention if you are looking for an insulation product that isn't made of plastic and basically fireproof I picked up some Rockwool/Roxul insulation board on amazon to insulate my battery box. It's being sold as "acoustic mineral wool" but all rockwool/mineral wool has acoustic suppression properties.
 
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Annod Industries, aka Ultra Heat makes a lot of heating pads for the industry.
Battle Born has free shipping
BBG2, BAT825-13v-15w is 8.5" x 25.5
BB10012, BAT830-13v-15w is 8.5" x 29.5"
Tax and shipping can add a LOT to the price.
 
One issue I see with wrapping a Battleborn battery is that the heat from the wrap may get to the BMS long before it heats the battery enough to be on the "safe" side. It depends on where the BMS is getting it's temperature reading from.

If the temperature range that is being used with the warming pad is higher than what I'm using (35° F - 45° F) then I could see that being OK.
 
Posted to illustrate that the Battle Born heaters are made by Annod Ultra.
BMS should be programmable.
Are you not compressing your cells? The compression frame limited me to what sides of the battery I could put warming pads on. I didn't think that putting the warming pad between the frame and the battery would be good for the pad.
Were you referring to my post?
The plan today is plastic straps, like metal bands for shipping.
Posted on this site somewhere.
 
Posted to illustrate that the Battle Born heaters are made by Annod Ultra.
BMS should be programmable.

Were you referring to my post?
The plan today is plastic straps, like metal bands for shipping.
Posted on this site somewhere.

Yes, it was intended for you. If you're using straps then the warming pads should work. I have 3/4" plywood on the ends of my compression frame, so warming pads wouldn't do much good wrapping the ends.
 
Is there a fail-safe that can be added if you use heating pads? I don't particularly like using a heating pad but don't see any other way around it at the moment.. If that is the case I am wondering if there is something that can be done to have backup shutoff in case the temperature controller fails or something.
 
Is there a fail-safe that can be added if you use heating pads? I don't particularly like using a heating pad but don't see any other way around it at the moment.. If that is the case I am wondering if there is something that can be done to have backup shutoff in case the temperature controller fails or something.
Do you have a BMS with temperature shutoff both high and low temperature??
 
@8milimeter, I wish you had posted larger pictures. I would have liked to zoom in on your build.

The folks I talked to on the phone, that sold me my kit, didn't say it outright but I'm pretty sure they are the OEM supplier for the Battleborn warming pads. The components I see in your pictures look exactly like the ones I have.
Larger Pictures !!
Today I finished the Solar installation. Flipped the 200amp switch and everything worked as designed.
I started this Van the end of June. Been working 10-12 hours days ever since. Almost done.
 

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Larger Pictures !!
Today I finished the Solar installation. Flipped the 200amp switch and everything worked as designed.
I started this Van the end of June. Been working 10-12 hours days ever since. Almost done.

Looks good! Isn't it fun working in tight spaces?
 
OK, I got my system running and have some serious questions. Hoping you guys and gals can help me.
I started my system up this morning (24 degrees "F"ambient) The battery temp was 32 degree "F". The Amps immediately went to 3.8, so I figured my two heating pads were working. Then 90 seconds later the current dropped back to .15 amps. (.15 = propane detector and Victron display). So I beat myself up all day trying to figure out why it stopped working. Triple checked everything and all was correct. Then this afternoon it dawned on me that the thermostat is between the battery and the heating pad. It would not take much time for the thermostat to get to 44 degree shut off. The battery was just 32 degree so it would not take much heat to raise it over the 34 degree start point of the pads. Does this make any sense ??
I hope to check it tomorrow morning, but the low ambient for tonight is only 32 and the batteries will most likely be of >34. Looking like it wont get below 32 degrees until December again here in MD.

Also, the more I think about it with the settings at 34 to 44 degrees with the thermostat mounted under the pad it will cycle on and off frequently, but the battery temperature will not get much above 34-36 degrees. Does this make any sense ??

Addition: I jumpered the ground to the pads to verify the Pads were working
 
I put my temperature sensor on top of the battery. The pads are on the two long sides of the battery. According to the manufacturer (Ultra Heat), I won't feel much heat on the back side of the pad as the foam does a decent job of insulating the heating part of the pad.

I don't have a full test of it yet, but I'm hoping that the heating pads radiate heat into the battery and not up into the battery "box". I'm not trying to heat the air, just the battery. If too much heat is radiated up into the box then I'm going to add a small amount of insulation on top of the temperature sensor to try and isolate it from the air. If that still doesn't work, then I'm going to change the activation range from 35° F-45° F to 40° F-50° F.

EDIT: I went back and looked at your install. I don't see why you couldn't put the temp sensor/controller on top of the battery.
 
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I may do that. They sent me an extra temp sensor. It would be easy to have one in two places to see the difference.
I am using 2" foil back fiberglass insulation to cover my batteries.
 
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