Reply
 
Thread Tools Display Modes
 
Old 08-03-2016, 11:55 PM   #1
Platinum Member
 
Davydd's Avatar
 
Join Date: Aug 2007
Location: Minnesota
Posts: 4,428
Default LiFeP04 Operating Temperatures

Here is a bit of information Advanced RV mentioned to me. To corroborate I asked Elite Power Solutions about it.

My question:

You say the operating temperature for 200ah GBS batteries is -4F to 149F. What is the effect on the batteries if totally disconnected and stored when temperatures drop lower than -4F. In Minnesota I can expect outside temperatures to drop to around -20F in the winter at times. My 800ah battery bank is not removable in any practical manner. I could face a storage situation when not using my RV where I cannot plug into shore power to utilize my heating pads to keep temperatures above freezing as I normally have done.

Elite Power Solutions' Answer:

Temperatures below -4F (-20C) will cause the electrolyte to freeze which will cause permanent damage to the batteries if it does not kill them entirely. If storage temperatures will go below -4F then you will need to heat the batteries to above -4F to prevent damage to the battery. There is no exception to this.

There you have it. You have to keep your lithium ion batteries above -4F (-20C). Also you can draw power from them at temperatures down to -4F and still be 90% efficient. You cannot charge them below freezing of 32F. Optimally you should keep your batteries stored and above 41F.
__________________

__________________
Davydd
2015 Advanced RV Ocean One Mercedes Benz Sprinter
Previous Class Bs:
2011 Great West Van Legend Sprinter
2005 Pleasure-way Plateau TS Sprinter
Davydd is offline   Reply With Quote
Old 08-04-2016, 12:08 AM   #2
Platinum Member
 
Join Date: Aug 2010
Location: Minnesota
Posts: 7,325
Default

That is an "ouch" for those of us in the frozen north

How are you going to handle that if you wind up without shore power in your winter storage area?
__________________

booster is online now   Reply With Quote
Old 08-04-2016, 01:01 AM   #3
Platinum Member
 
Boxster1971's Avatar
 
Join Date: Mar 2012
Location: Maryland
Posts: 862
Default LiFeP04 Operating Temperatures

Davydd - thanks for posting this information. I was aware that LiFePO4 batteries have some cold temp issues. This is good info from a reliable source, more so than some of the Chinese manufactures questionable information. It also confirms that I made the right choice staying with Lifeline AGM batteries when I did my upgrade. I have been in Minnesota for weeks in February and seen overnight temps at -20F all week. Here is the temperature considerations page from Lifelines manual. A fully charged AGM can handle some very low temps.



- - Mike
2013 Airstream Interstate from 2012 Sprinter 3500 tall & long
__________________
2013 Airstream Interstate Lounge EXT on 2012 Sprinter 3500 170Ext
Formerly: 1973 Dodge B300 DIY pop-top conversion
Boxster1971 is offline   Reply With Quote
Old 08-04-2016, 01:38 AM   #4
Platinum Member
 
Davydd's Avatar
 
Join Date: Aug 2007
Location: Minnesota
Posts: 4,428
Default

Quote:
Originally Posted by booster View Post
That is an "ouch" for those of us in the frozen north

How are you going to handle that if you wind up without shore power in your winter storage area?
This winter it will not be a problem I hope as we don't anticipate moving until March to an HOA development. I'll just stay plugged in as always. Looks like I'll be looking for inside storage with power or temperature control or I will just have to head south in the RV for the winter. We plan to be in the Washington DC area for Christmas.

The winter before last it would not have been much of a problem when the temperature rarely got below 0. In years past we had one time when it got down to -43 in our woods. The official temperature was about a -32. Staying plugged in the batteries stay warm from the heating pads designed to keep the temperature above 41 degrees.

I found a couple of LiFeP04 sources that said temperatures could go down to -22F. That may be true or maybe not. Elite Power Solutions say no.
__________________
Davydd
2015 Advanced RV Ocean One Mercedes Benz Sprinter
Previous Class Bs:
2011 Great West Van Legend Sprinter
2005 Pleasure-way Plateau TS Sprinter
Davydd is offline   Reply With Quote
Old 08-04-2016, 01:40 AM   #5
Site Team
 
avanti's Avatar
 
Join Date: Jul 2013
Posts: 3,133
Default

Interesting.

OK, so here's a challenge for you "armchair" theoreticians:
If DavyDD started a -20 degree cold spell with his awesome battery completely charged, how long could he run his heating pads at just enough current to keep the batteries above -4 degrees? Don't forget to take into account the battery self-heating under load.
__________________
Formerly: 2005 Airstream Interstate (Sprinter 2500 T1N)
Now!: 2014 Great West Vans Legend SE (Sprinter 3500 NCV3 I4)
avanti is online now   Reply With Quote
Old 08-04-2016, 01:43 AM   #6
Platinum Member
 
Davydd's Avatar
 
Join Date: Aug 2007
Location: Minnesota
Posts: 4,428
Default

Quote:
Originally Posted by Boxster1971 View Post
Davydd - thanks for posting this information. I was aware that LiFePO4 batteries have some cold temp issues. This is good info from a reliable source, more so than some of the Chinese manufactures questionable information. It also confirms that I made the right choice staying with Lifeline AGM batteries when I did my upgrade. I have been in Minnesota for weeks in February and seen overnight temps at -20F all week. Here is the temperature considerations page from Lifelines manual. A fully charged AGM can handle some very low temps.
On the road a fully charged lithium ion battery is not going to be a problem as the 12v heating pads will keep the battery temperatures above 41 degrees and lithium ion batteries charge fast. It is unoccupied storage not plugged into shore power that is the problem. One only needs a 15 amp plug in since the air conditioning won't be needed.
__________________
Davydd
2015 Advanced RV Ocean One Mercedes Benz Sprinter
Previous Class Bs:
2011 Great West Van Legend Sprinter
2005 Pleasure-way Plateau TS Sprinter
Davydd is offline   Reply With Quote
Old 08-04-2016, 02:03 AM   #7
Platinum Member
 
Davydd's Avatar
 
Join Date: Aug 2007
Location: Minnesota
Posts: 4,428
Default

Quote:
Originally Posted by avanti View Post
Interesting.

OK, so here's a challenge for you "armchair" theoreticians:
If DavyDD started a -20 degree cold spell with his awesome battery completely charged, how long could he run his heating pads at just enough current to keep the batteries above -4 degrees? Don't forget to take into account the battery self-heating under load.
No armchair. I have already experienced and monitored it. I will draw 10 amps per hour to keep them above 41 degrees. I have to be well above -4. I have to be above freezing to be able to charge. That can be accommodated easily occupied and on the road with an 800ah battery bank just driving less than an hour or fast idling for one hour. Most of the time when temperatures are somewhere above 20 degrees the internal battery temperature will suffice to keep them above freezing and the heating pads won't come on. At Mike Wendland's Winterfest last January when the temperatures stayed in the mid 20s the heating pads never came on. I camped on the road for a week with temperatures always below freezing day and night and down to 0 F. one night. It was never a problem. Given that the battery temperature will most likely run anywhere from 10-20 degrees hotter than ambient and most daytime temperatures rise above -4 I probably could theoretically get by but only if I am there to monitor it.
__________________
Davydd
2015 Advanced RV Ocean One Mercedes Benz Sprinter
Previous Class Bs:
2011 Great West Van Legend Sprinter
2005 Pleasure-way Plateau TS Sprinter
Davydd is offline   Reply With Quote
Old 08-04-2016, 02:21 AM   #8
Platinum Member
 
Join Date: Nov 2015
Location: CA
Posts: 1,575
Default

Quote:
Originally Posted by Davydd View Post
I found a couple of LiFeP04 sources that said temperatures could go down to -22F. That may be true or maybe not. Elite Power Solutions say no.
Is the LiFeP04 electrolyte freezing point affected by the battery state of charge?
cruising7388 is offline   Reply With Quote
Old 08-04-2016, 02:21 AM   #9
Site Team
 
avanti's Avatar
 
Join Date: Jul 2013
Posts: 3,133
Default

Quote:
Originally Posted by Davydd View Post
No armchair. I have already experienced and monitored it. I will draw 10 amps per hour to keep them above 41 degrees. I have to be well above -4. I have to be above freezing to be able to charge.
You miss my point. I agree with you that when the vehicle is in use there is no issue. I was thinking about storage, and how long of a cold spell you cold weather without shore power. It takes a LOT less energy to keep the batteries at -4 than it does to keep them at +41. My intuition is that we might be surprised how long one could go in cold storage with a properly-designed system. But, only theory will tell the tale.
__________________
Formerly: 2005 Airstream Interstate (Sprinter 2500 T1N)
Now!: 2014 Great West Vans Legend SE (Sprinter 3500 NCV3 I4)
avanti is online now   Reply With Quote
Old 08-04-2016, 03:32 AM   #10
Platinum Member
 
Davydd's Avatar
 
Join Date: Aug 2007
Location: Minnesota
Posts: 4,428
Default

When you take a batteries offline they will eventually and probably quickly equalize out with ambient temperature. Only when in operation do they stay warmer. So unattended offline you have to keep them warm by staying plugged in with heat on them or inside above -4. There's no theory about that. I know.
__________________

__________________
Davydd
2015 Advanced RV Ocean One Mercedes Benz Sprinter
Previous Class Bs:
2011 Great West Van Legend Sprinter
2005 Pleasure-way Plateau TS Sprinter
Davydd is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


» Featured Campgrounds

Reviews provided by

Powered by vBadvanced CMPS v3.2.3

All times are GMT. The time now is 11:30 PM.


Powered by vBulletin® Version 3.8.8 Beta 4
Copyright ©2000 - 2019, vBulletin Solutions, Inc.