Cold weather

Where I am in northeast Ohio we don't get COLD like the Canadians who live in a block of ice for 4 months a year. We DO get into the low 30s in November, then the ow 20s in December, then the teens to single digits in January. When we get down into the area where I need to worry I will just take it out of the trailer and bring it in. But DID have a thought. What would be the hard of putting the battery inside a thermal cooler? If it keeps cold stuff cold, it will also keep stuff from GETTING cold. Mount terminal posts on the cooler, connect the battery to the terminals posts..... the battery stays insulated form the cold. What are your yeas and nays on that idea?

A cooler may slow the rate of change, but won't stop the cold.

On the other side, if you put ice in a cooler and leave it in 90* weather, how long before it's all melted and 80*? May take awhile, but it still gets warm.

I have had blue ice packs in the cooler for 14 hours and they were still cold. No longer frozen, but still cold. I am going to test this with a thermometer tomorrow night. I have to go buy an accurate one. "For science!!"

So Eddie how about making a solar dump load device to heat some water in the cooler that would extend its time being warm

Craig said:

So Eddie how about making a solar dump load device to heat some water in the cooler that would extend its time being warm

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Hmmm...... That is interesting. Right now for giggles I have a quilt wrapped around it. Just with the logic of some is better than none and based on how that quilt keeps ME warm. My thought process is that it is equally as much about keeping cold out as keeping warm in. Maybe line the cooler with denim insulation. (Never fiberglass. I have an animal in that trailer!) Cold is a lot about wind speed as actual temperature too, and inside a trailer there is no wind. (Well..... after Taco Bell.) So just like getting out of the wind makes a cold day a little warmer, this is something to study. I brought in my clock face type thermometer from outside to warm it up the the 66 degrees that the house stays at and when it get there I put it in the cooler and put that into the trailer. Before I got to bed I will check that thermometer against the outside temp. In a cooler, in the trailer, that seals so tight that when you close the door from inside your ears almost pop.

Because we want to know. For science!!

eddie1261 said:

Just with the logic of some is better than none and based on how that quilt keeps ME warm.

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It doesn't. The human body generates as much heat as a 100watt bulb. The quilt traps some of that heat from escaping.

But press on with your experiment......

I agree with Rider ..... insulation slows heat loss but doesn't stop heat loss. In order to maintain a temp inside the cooler at VERY cold temperatures over a long period of time you will need a heat source.

eddie1261 said:

Cold is a lot about wind speed as actual temperature too, and inside a trailer there is no wind. (Well..... after Taco Bell.) So just like getting out of the wind makes a cold day a little warmer,

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Not really. Wind feels colder because of evaporation of moisture off your skin. When you step out of the wind, evaporation lessens, and only appears warmer. The temp never changed. The temp of a battery in or out of the wind will not change the apparent temp as there is no skin and no moisture. That's what 'wind chill' is all about.

Rider said:

Not really. Wind feels colder because of evaporation of moisture off your skin. When you step out of the wind, evaporation lessens, and only appears warmer. The temp never changed. The temp of a battery in or out of the wind will not change the apparent temp as there is no skin and no moisture. That's what 'wind chill' is all about.

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However, wind does play a part in sapping heat from a box. Still wind acclimates temp slower than fast wind.
Also, fiberglass batts with wind blowing through them do practically nothing, sealed from the wind, they slow heat transfer much better.

Supervstech said:

However, wind does play a part in sapping heat from a box. Still wind acclimates temp slower than fast wind.
Also, fiberglass batts with wind blowing through them do practically nothing, sealed from the wind, they slow heat transfer much better.

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Agreed. Not much heat to sap, but I agree with that.

Well, first, when it gets cold enough that really is in caps, my battery will be inside in my office quietly resting on a desk. Second, when it gets cold enough that really is in caps, I am also inside. My lithium battery will never see anything below 30 degrees. As the trailer sits in the driveway it is plugged into shore power so I can put a heater in there if I want to. I prefer to just pull the battery out.

Now, to stay in "smart ass" character that you have come to know of me, let me ask this. In terms of the earlier half in jest comment that the blanket kept me warm, I don't know to measure this, but there has to be some property of an insulating blanket keeping cold out as much as it keeps heat in. I put the thermostat in the cooler (or in this case, warmer, though it doesn't really warm) into the trailer at 8:30. I will check it at 11 and see how far from 66 it has fallen.

I don't know why this kind of minutia interests me.....

If you want to go down the rabbit hole...

Having an insulated box would definitely be step one, and a cooler is a pretty good starting point especially if you find one that isn't overkill for the battery you're putting inside. Thinking in terms of space, but also energy used to sustain set temperature. Applying gentle warmth evenly to a dense hunk of battery... the holy grail.

If you have some low voltage disconnect in place you could run a 12v heat source Lots to be had from China in pretty much any dimension/wattage you like. Less selection if you buy from within the states. Search '12v 3d printer heat pad' if interested, or 'silicone 12v heat pad 3m'. Should get you on the right track. Incubator heaters if found in a low enough wattage are also an option.

Around $8 will get you a DC thermostat type deal with a probe. Set temperature, operates heater to desired temperature with hysteresis so you don't get constant on/off cycles. Battery keeps itself warm, low voltage disconnect prevents it from killing itself. This option is cheap, reliable, and requires a small screwdriver at most. But from the recent weeks I've spent testing battery heating options, insulate the box itself (or start with a cooler) and apply heat below/above/around the battery. Otherwise you're applying a heat source in direct contact with the batteries and you're stuck trying to not exceed crazy temps at your heat source, while still trying to keep everything else at an acceptable temperature.

Pretty cost effective, and effective, if done right. Having space to play with will make it a lot easier while also increasing the area to keep warm, gotta find that balance.

You also have a ton of options if you want to use wall current to maintain a set temperature, that's a pretty standard automotive item.

eddie1261 said:

Now, to stay in "smart ass" character that you have come to know of me, let me ask this. In terms of the earlier half in jest comment that the blanket kept me warm, I don't know to measure this, but there has to be some property of an insulating blanket keeping cold out as much as it keeps heat in. I put the thermostat in the cooler (or in this case, warmer, though it doesn't really warm) into the trailer at 8:30. I will check it at 11 and see how far from 66 it has fallen.

I don't know why this kind of minutia interests me.....

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a recent thread on insulating battery boxes and effectiveness. luthj has some uhh... in depth stuff that was over my head.

As we have this discussion, and it has been very good so far, remember that my trailer is 121 cubic feet of space, so if I put a ceramic heater in there with the thermostat set at 50 degrees it will keep the inside warm enough to not allow freezing temps inside and not kick on that often. For perspective, it was 88 degrees outside and humid when I was in there working on wiring. I turned the AC on at the lowest setting, and in 5 minutes I had to turn it off because ot was cold in there.

eddie1261 said:

As we have this discussion, and it has been very good so far, remember that my trailer is 121 cubic feet of space, so if I put a ceramic heater in there with the thermostat set at 50 degrees it will keep the inside warm enough to not allow freezing temps inside and not kick on that often. For perspective, it was 88 degrees outside and humid when I was in there working on wiring. I turned the AC on at the lowest setting, and in 5 minutes I had to turn it off because ot was cold in there.

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121CUBIC feet? My freezer is bigger than that...

Supervstech said:

121CUBIC feet? My freezer is bigger than that...

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4 wide, 8 long, 42" high at the ends, 46" high in the middle. It's is a hotel room on wheels. Not an RV in any way. Did you watch the video when I posted it?

And actually, it is 117, not 121. Recalculated.

I was trying to be funny... van life all the way man.

eddie1261 said:

4 wide, 8 long, 42" high at the ends, 46" high in the middle. It's is a hotel room on wheels. Not an RV in any way. Did you watch the video when I posted it?

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Where’s the video?

Heck, just take the battery to bed with you.

Supervstech said:

Where’s the video?

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