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Hi, I'm looking for Australian "Bloody Hot" weather advice on batteries.

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Shtonkalot

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Feb 5, 2020
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Hi from Australia. I found these forums from the youtube videos.
Pretty much every video Will seems disappointed by the lack of low temp cut off in a battery BMS and seems to believe that it is a necessary inclusion. Will doesn't live in Australian weather conditions quite obviously.
Where I am, and for most of Australia's residents spread over the country we never see freezing temperatures.
What we do see is a lot of hot weather, stretches of plus 40 degree C , 100 degree F are not unusual in my living circumstances.

I'd very much like to put a lithium battery inside an enclosed metal trailer I have. The trailer will get ventilation and will be covered in solar panels with an airgap underneath. I will monitor temperatures before putting in an expensive battery and will find a way to get them maintainable. I'm considering things like watercooling for batteries :p

What I'd really like to know is more about high temperatures issues and equipment known to tolerate high temp conditions well.
Does anyone here have that info or know where to find it?
 
JC777 said:
Here's another one. http://nordkyndesign.com/practical-characteristics-of-lithium-iron-phosphate-battery-cells/. Could you go underground or does the system need to be mobil?
Click to expand...
Cheers mate. I understand the general info on the chemistry. What I'm really after is some knowledge on how heat affects particular cells I can purchase. Are some better than others in the heat?
And BMS options too, with heat tolerance being a bigger desire than bluetooth ;)

I'm thinking some aluminium cased cells may be easier to keep cool than plastic for example. I just have no experience.

The system does need to be mobile. My new home is a motorhome and has a trailer with me. I already have a solar system in the motorhome but would like a second one in the trailer. I am prepared to modify the trailer to allow for cooling, and I plan to have some sort of temp controlled cooling whether fans or something more extreme.

I guess I want to know where the limits are, how to measure them accurately, how to keep some expensive cells from becoming cheap bricks :p
Hoping to learn from others mistakes before I make my own.
 
Shtonkalot said:
I'm considering things like watercooling for batteries :p
Click to expand...

Many EV packs like Tesla's are already set up (piped) for water-cooling. All you'd have to do is pump water through them. You have to figure out if that would be more efficient than just using a small window AC on a blocked off insulated section of the trailer. Or, if you don't have much rain, look into making a battery cellar.

I've got the same problems in Florida...and I haven't decided on my perfect solution yet.
 
SolarRat said:
Many EV packs like Tesla's are already set up (piped) for water-cooling. All you'd have to do is pump water through them. You have to figure out if that would be more efficient than just using a small window AC on a blocked off insulated section of the trailer.
Click to expand...
Thanks mate, that's an interesting thing to look out for. I think watercooling would be the most efficient method I could use. Only need to run a small pump and fan to make it actively cool and I bet the increased thermal mass and runaway would keep it cooler when not running if done right. I'd love to get away with heatsinks and fans but I think I'd be struggling to cool below ambient before adding battery heat to the system on a hot day.
 
I don't have an answer to keep your cells below 45C.

These engineers might.
. ;) These are Early Sinopoly tests. Note the 45.cal test.....talk about DIY.:cool:
 
Maybe something like having your cells sitting in a tub of silicon oil or glycol - then using a fountain water pump to circulate the fluid through a long copper pipe buried 1.5 meters or so deep. As long as the top vent is kept above the fluid it won't bother the cells any.

Another thought that comes to mind is having the fluid pumped through a copper pipe wrapped in burlap with a soaker hose on top of it.

Cheap and easy active cooling.
 
There is a large amount of folks in OZ using Winston Cells with a lot of success for years. Now I don't know if that is because they are more readily available or if it's because they are just really good for that climate zone. I do know there are LFP made for colder temps but I don't know about hotter temps. Tesla Packs are not like LFP though, bit of a different beast and I can't imagine what they would cost in OZ, certainly not on the cheap side I would think.

One fellow in OZ had a novel approach to the problem, he installed a "Dog House Air Conditioner" just a little 12V one. It was a while ago and I can't remember where I saw the post (not this forum) but it stuck with me as quite a smart idea. https://www.amazon.com/s?k=Dog+house+Air+Conditioner&ref=nb_sb_noss

Every BMS I have seen has Hi Temp cutoff, Low temp hadn't been paid that much attention to until recently, that's why there is so much hubbub about Low Temp cutoff and besides, it's winter up here in the north and when t's -17 outside, you think & grumble about it.
 
Shtonkalot said:
Hi from Australia. I found these forums from the youtube videos.
Pretty much every video Will seems disappointed by the lack of low temp cut off in a battery BMS and seems to believe that it is a necessary inclusion. Will doesn't live in Australian weather conditions quite obviously.
Where I am, and for most of Australia's residents spread over the country we never see freezing temperatures.
What we do see is a lot of hot weather, stretches of plus 40 degree C , 100 degree F are not unusual in my living circumstances.

I'd very much like to put a lithium battery inside an enclosed metal trailer I have. The trailer will get ventilation and will be covered in solar panels with an airgap underneath. I will monitor temperatures before putting in an expensive battery and will find a way to get them maintainable. I'm considering things like watercooling for batteries :p

What I'd really like to know is more about high temperatures issues and equipment known to tolerate high temp conditions well.
Does anyone here have that info or know where to find it?
Click to expand...
I would like to ask that you send the heat here, but I suspect that "bloody hot", means that it is unpleasant, possibly life threatening and oppressive to the point of curtailing any outdoor activities and forcing people into shade and air conditioning.
 
offgriddle said:
I would like to ask that you send the heat here, but I suspect that "bloody hot", means that it is unpleasant, possibly life threatening and oppressive to the point of curtailing any outdoor activities and forcing people into shade and air conditioning.
Click to expand...
That is a fairly good description of the weather.
Fire tornadoes are a bigger thing this year.
www.abc.net.au

This is how a bushfire can flip a fire truck

The science behind rotating fire systems is still being worked out, but there is no denying they are incredibly dangerous.
www.abc.net.au www.abc.net.au
 
Shtonkalot said:
That is a fairly good description of the weather.
Fire tornadoes are a bigger thing this year.
www.abc.net.au

This is how a bushfire can flip a fire truck

The science behind rotating fire systems is still being worked out, but there is no denying they are incredibly dangerous.
www.abc.net.au www.abc.net.au
Click to expand...
I had no idea that Australia struggles so with so many deadly fires, I'm so sorry.
Shtonkalot said:
That is a fairly good description of the weather.
Fire tornadoes are a bigger thing this year.
www.abc.net.au

This is how a bushfire can flip a fire truck

The science behind rotating fire systems is still being worked out, but there is no denying they are incredibly dangerous.
www.abc.net.au www.abc.net.au
Click to expand...
I had no idea that Australia struggled with frequent, quick spreading, dangerous wildfires, I am sorry to hear this. ?
 
Conditions have worsened over the past few years drastically. The public awareness of the dangers has always been high in Australia.
This season has been hard with over 20 lives and approx 2000 homes lost.

I lost my home and everything I owned. In fact that is why I am here looking for solar advice. This is my last solar rig..

IMG_20191017_092547.jpg
IMG_20191017_092507.jpg

In the first pic is a 24v 60a solar / 30a AC charger with 3000w inverter and 6 190ah AGM batteries.
Just installed a few months before the fire went through.
 
Steve_S said:
Every BMS I have seen has Hi Temp cutoff, Low temp hadn't been paid that much attention to until recently, that's why there is so much hubbub about Low Temp cutoff and besides, it's winter up here in the north and when t's -17 outside, you think & grumble about it.
Click to expand...

Same. On my first install I actually designed my own low temp cut-off since it was not available.

Back in topic: don't you have excess solar so you could just run a small airco? I do the opposite here up north: I have my batteries in an insulated enclosure and have a small heating element to keep them warm in winter. You only need a little bit of power if you keep the box insulated. This would work the opposite way as well. You could even use thermoelectric cooling and some thermal mass (gel for example) so you would even keep them cool for some time without power.
 
O think you guys are really over thinking some of these solutions .... so Shtonkalot ... i work in the oil industry in South Texas -- its the middle of winter here -- our temp yesterday was 84F / 29C .. HEAT is our number one concern ... BUT with that said -- Lithium is very forgiving up to about 150F / 65C ... Our summers here will easily get in the 115F / 46C .. our batteries are typically enclosed in some metal container that turns into a oven space quickly ...

For our smaller 200 / 280 aH 3.2V LiFePO4 Aluminum sided batteries all we do is put a small spacer between them and ensure that all four sides of no batteries are touching ... we also mount some high speed "computer" fans attached to a thermostat that kicks on when the battery temp reaches 100F ... the fan is NOT designed to cool the battery BUT to dissipate heat ... Theoretically - or practically - since LFP loves 72F as its favourite temp I guess you could have it kick on at 72 but for us that would mean they would run ALL the fricking time ...

As long as the area you have the LFPs are ventilated to allow heat exchange (air movement) then the fan concept is cheap and highly effective ... At about 150 degrees we have our LFPs disconnect unless its on Emergency equipment - which of course I'm just going to melt them down in that case ..

But as long as you can push air through and around the batteries you will be fine ... We actually use those inexpensive Chinese temperature controls off Ebay and Alibaba BUT make sure you get some good solid computer fans - the metal ball bearings type --

BUT with that said -- we have seen our battery compartments be 135F and the LFPs are just smiling ... I think for our batteries the magic NO GO number is 157 F ... Check your batteries for specific numbers though
 
ghostwriter66 said:
For our smaller 200 / 280 aH 3.2V LiFePO4 Aluminum sided batteries all we do is put a small spacer between them and ensure that all four sides of no batteries are touching ... we also mount some high speed "computer" fans attached to a thermostat that kicks on when the battery temp reaches 100F ... the fan is NOT designed to cool the battery BUT to dissipate heat ... Theoretically - or practically - since LFP loves 72F as its favourite temp I guess you could have it kick on at 72 but for us that would mean they would run ALL the fricking time ...
Click to expand...
How long have they been in service?
 
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