Elevating this from another topic. I have two Renogy Lipo batteries that I hope to store in my cabin over the winter. This will mean they are sitting, disconnected, through a couple of very cold winter months, getting down to below zero. Is this potentially damaging? Some info on the web says it’s fine, but Renogy says storage should be above 32 degrees. They also told me the BMS would shut down the battery at low temps? Any info would be appreciated.
Lipo battery winter storage
- Thread starter dcaulton
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TCgreg
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Not sure if you are talking Celsius of Fahrenheit. Their website states that for periods of less than 3 months they can be stored down to 14 degrees F or -10 degrees Celsius. Will it be colder than that? If so I would find a different way to keep them at a more moderate temperature.
MrNatural22
?SW sunshine =⚡️⚡️lit up thru the darkness✌️
They’re pretty cold tolerant to a point but you may want to think about taking them with you for the season. They’re light, safe and easy to transport. That way no expensive batteries to worry about.
Yeah, sadly I fly home so not an option.
Offgrid97
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Any way you could build a black box and put it in the window or where the sun would hit it? That would you think be a way to help build some heat. I have the same situation only I could bring them home. Was toying around with the idea of using an aquarium heater with a temperature gauge that would keep my batteries warm but also be able to charge them if they're above 32 degrees. Or not charge via a temp switch if batteries are below 32. Those heater pads dont take many watts.
Seems to me a heater pad in a well insulated box would do the trick.
Offgrid97
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I would think that you could go days with no sun and still be good to go.
Off Grid Mobile
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kwgrant
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I would dig a hole below the frost line, put the batteries in a box in the hole, and insulate it well.
I'm looking at a battery from Expion360 and they're telling me it can safely be stored down to -40 at a 30-40% state of charge.
yes was thinking about underground storage as well. I also found that theoretically lipo batteries should be able to get VERY cold if not charged or discharged. Renogy seems overcautious. Also, I doubt their claim that the BMS has a thermometer and will shut the battery down if too cold...
MrNatural22
?SW sunshine =⚡️⚡️lit up thru the darkness✌️
I believe what is meant is it won’t accept a charge below freezing, not that it would shut down. It can still be used below 0c or 32f it just can’t be charged because that would cause damage to the battery.
Off Grid Mobile
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The battery in question can go down to only -4 it can only be charged again at 40 degrees or higher use a seedling heater if need be to keep warm just a thought .
kwgrant
New Member
I've done allot of research and for storage every lipo manufacturer or builder spec sheet says to keep the battery above freezing in storage. Maybe this is for liability so nobody accidentally charges the battery below freezing?
In the few mdsd /sds I've found, there is no caution of keeping the battery above freezing.
I would really like to know if a lipo battery can safely be stored down to -40. There are many remote camps that these batteries would work great at, but if you had to bury the batteries or bring them back to town, that makes them less attractive.
When I asked Expion360, they said they're safe to -40 as long as the battery isn't connected to anything and is at a 30-40% state of charge.
In the few mdsd /sds I've found, there is no caution of keeping the battery above freezing.
I would really like to know if a lipo battery can safely be stored down to -40. There are many remote camps that these batteries would work great at, but if you had to bury the batteries or bring them back to town, that makes them less attractive.
When I asked Expion360, they said they're safe to -40 as long as the battery isn't connected to anything and is at a 30-40% state of charge.
Yes this is the question. Many places say cold is good for storage; manufacturers specifically list minimum temps around freezing. People seem to universally say it’s a bad idea to charge the battery when very cold. But I think maybe they’re generalizing the charging caution to storage.
one factor is that the battery isn’t water based so there’s likely nothing magical about 32 f. I bet Renogy would give will access to someone more knowledgeable than tier 1 support to get a better answer?
kwgrant
New Member
Here's a great artical on lithium batteries.
www.solacity.com
How to Find Happiness With LiFePO4 (Lithium-Ion) Batteries – Solacity
By: Rob Beckers You have just sold your first-born into slavery, remortgaged the house, and bought yourself a lithium-ion battery! Now you want to know how to take care of your precious new purchase: How to best charge lithium-iron batteries, how to discharge them, and how to get the maximum...
www.solacity.com
kwgrant
New Member
The Trojan Trillium data sheet says they're safe to store at -40. I know these aren't the batteries the op was asking about, but can there really be that much difference between LiFep04 cells? Maybe it's the BMS CPU that doesn't like the cold weather?
I guarantee no CPU suffers from cold temps. I know solid-state devices and they're happy sitting in a bath of supercooled nitrogen.
PHoganDive
Solar Enthusiast
The performance of most silicon semiconductors improves at colder temperatures.
b.james
New Member
The chip used has an internal temp sensor. I think that's for high heat and low. The chip can turn a mosfet off and that's the battery disconnected . Easily done.
Now if you dug a hole under the cabin and took a styrene box and lined it with some of that green freezer insulation or any good insulation meant for freezers in boats then surely that would be enough? At least a small heater plate would work better there and use less current off the battery. If it drains too much again the BMS would turn off.
The separators do in fact have liquid electrolyte . It is impregnated in there so I guess if it got cold enough it could freeze and expand . Not much room in there for that so it has to do damage.
Now if you dug a hole under the cabin and took a styrene box and lined it with some of that green freezer insulation or any good insulation meant for freezers in boats then surely that would be enough? At least a small heater plate would work better there and use less current off the battery. If it drains too much again the BMS would turn off.
The separators do in fact have liquid electrolyte . It is impregnated in there so I guess if it got cold enough it could freeze and expand . Not much room in there for that so it has to do damage.
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