RV Trip Planning Discussions

Go Back   iRV2 Forums > RV SYSTEMS AND TECHNOLOGIES FORUMS > Going Green
Click Here to Login
Join iRV2 Today

Mission Statement: Supporting thoughtful exchange of knowledge, values and experience among RV enthusiasts.
Reply
  This discussion is proudly sponsored by:
Please support our sponsors and let them know you heard about their products on iRV2
 
Thread Tools Search this Thread Display Modes
 
Old 09-27-2020, 12:04 PM   #15
Senior Member
 
Pappion's Avatar
 
Join Date: May 2018
Location: Benson AZ
Posts: 306
vsheetz, thanks for the link. Battery University was little help. Battle Born recommended 1/2 hour absorption per 100AH. Very little info on bulk charge behavior prior to absorption. Seems like SOC is easier to determine by voltage while charging, but difficult while discharging.

I ordered a Victron SmartSolar 100/50 charge controller.
https://battlebornbatteries.com/prog...ge-controller/


I'm getting cold feet on the LiFeP04 batteries. I don't like how 45c (113f) can damage them. That would cause me storage issues in AZ in summer which has many 35c - 47c days. That's why I put advanced AGM with nano-carbon on my last camper. They got old, so I let them go with the camper. No longer available.
__________________
2017 Winnebago Minne 2201DS TT
2010 Chalet XL1930 A-Frame SOLD
Retired Engineering Technician
Pappion is offline   Reply With Quote
Join the #1 RV Forum Today - It's Totally Free!

iRV2.com RV Community - Are you about to start a new improvement on your RV or need some help with some maintenance? Do you need advice on what products to buy? Or maybe you can give others some advice? No matter where you fit in you'll find that iRV2 is a great community to join. Best of all it's totally FREE!

You are currently viewing our boards as a guest so you have limited access to our community. Please take the time to register and you will gain a lot of great new features including; the ability to participate in discussions, network with other RV owners, see fewer ads, upload photographs, create an RV blog, send private messages and so much, much more!

Old 09-28-2020, 08:47 AM   #16
Senior Member


 
Join Date: Jul 2019
Posts: 306
Quote:
Originally Posted by Pappion View Post
I'm getting cold feet on the LiFeP04 batteries. I don't like how 45c (113f) can damage them. That would cause me storage issues in AZ in summer which has many 35c - 47c days. That's why I put advanced AGM with nano-carbon on my last camper. They got old, so I let them go with the camper. No longer available.

Most mfg datasheets I've seen for LiFePO4 are around the same. The one I pulled to double check my numbers says that you can charge them from 32 to 120 F, operate -4 to 140 F. and store from -4 to 113 F - which I assume means store at a sustained temperature for months on end - something you won't have in your application.
__________________
2015 Keystone Alpine 3730FB, 2019 Ram 3500 HO/AISIN CCLB DRW, 2020 JLUR
Primarily off-grid living w/ 2925W solar and 22.8kWh LiFePO4, 30K 240V multi-split,
a custom bladder/pump/monitor setup so we can use water as we wish, and more
n0arp is offline   Reply With Quote
Old 09-28-2020, 10:59 AM   #17
Senior Member
 
Join Date: Feb 2018
Posts: 872
My Reno days are not as hot as your Arizona days. I have been logging my battery, pass-through storage and outside trailer temperatures since July with my Cerbo GX. My batteries are stored inside under a polycarbonate twin wall cover between my sit and sleep sofa and the wall adjacency to the front pass through storage. They stay at least 10 degrees cooler than the daytime highs and about 10 degrees warmer than the night time lows.

I keep one window on the east side of the trailer open and a bathroom fantastic fan on which is under a 300 watt solar panel which protects it from rain. My daytime highs are about 35-40 degrees warmer than the nighttime lows. The inside trailer temperatures are moderate compared to the outside temperatures.

In the cold months I leave the window and fan closed. The overnight lows inside the trailer keep the batteries from being too low to take a charge in the daytime when the sun is shining on the panels.

My seven 100 amp-hour BattleBornBatteries are not inexpensive but perform very well with my 1440 watts of solar on the roof and my VE Multiplus 3000VA 12 volt inverter/charger. When camping in the summer we run the air conditioner when the sun is shining using solar/battery power to the inverter. We supplement the roof top solar with 640 watts of portable panels. I have enough battery to run the air conditioner until the evening temperatures cool down after sunset.
__________________
Jeff--
Arctic Fox 22G w/1440 watts solar/GMC2500HD Double Cab with Leer Cap w/265 watts solar
astrocamper is online now   Reply With Quote
Old 10-03-2020, 12:42 AM   #18
Senior Member
 
Join Date: Sep 2017
Location: Northern California
Posts: 646
Like LiFePo4 Battery internal info.

I like having the BT from the LiFePo4 BMS. It pretty much tells me all I want to know and helps ensure my $$$$$ batteries are being treated well. It gives me important bits like battery internal temperature, SOC, balance, charge/discharge current, etc. It even tells me that my solar is working as it should by looking at the battery current and looking around at my loads and where the sun is. I check the readouts on the three solar controllers only rarely and as an occasional check to be sure they are working as they should since the battery only tells me the total of the three. As others have mentioned, battery internal temperature never gets as low as the ambient or as high as the ambient. That's very useful information with LiFePo4.
__________________
2020 GMC Denali 2500HD Crew 4X4 Gas 6.6L Rockwood 8280WS (30' 5th)
1000W solar; 322AH LFP battery,
900W PSW inverter, NovaKool RFU9000 fridge
hclarkx is offline   Reply With Quote
Old 10-16-2020, 05:01 PM   #19
Senior Member
 
Pappion's Avatar
 
Join Date: May 2018
Location: Benson AZ
Posts: 306
OP posting... I bought the Victron Smart Solar 100/50 with bluetooth. Installed 4 days ago. Adaptive Absorption and Tail Current exit are great features for AGM (lead acid) charging. The logs are great for evaluating charge and use patterns.

I concluded that the 2x 100AH AGM batteries this TT came with won't be enough for me this winter. Furnace blower is 7.5A, Laptop is 4-7A, TV/DVD about 7A.

I am looking at a 200AH LiFeP04 to start with. No rush, they seem to get cheaper as I wait. Right now I am plugged in and simulating boon docking by shutting off the breaker to the converter.
__________________
2017 Winnebago Minne 2201DS TT
2010 Chalet XL1930 A-Frame SOLD
Retired Engineering Technician
Pappion is offline   Reply With Quote
Old 10-17-2020, 12:19 AM   #20
Senior Member
 
Join Date: Sep 2017
Location: Northern California
Posts: 646
Quote:
Originally Posted by Pappion View Post
OP posting... I bought the Victron Smart Solar 100/50 with bluetooth. Installed 4 days ago. Adaptive Absorption and Tail Current exit are great features for AGM (lead acid) charging. The logs are great for evaluating charge and use patterns.

I concluded that the 2x 100AH AGM batteries this TT came with won't be enough for me this winter. Furnace blower is 7.5A, Laptop is 4-7A, TV/DVD about 7A.

I am looking at a 200AH LiFeP04 to start with. No rush, they seem to get cheaper as I wait. Right now I am plugged in and simulating boon docking by shutting off the breaker to the converter.
Neat. I have a load calculation spreadsheet if you are interested. It will tell you how much battery you need to get through the night with a given SOC remaining as a cushion. You enter the load current and the day and night hours of use (or fraction of an hour). Below is the Winter side of the load list.

It also estimates solar required for locations you might visit using 50 years of solar data.

Did you see LoveYourRV's test and tear-down of a $620 SOK 100 AH LFP? I was impressed. It holds up considerably better than Battleborn below 15% SOC. It can be dismantled!! Cells and BMS can be replaced.

Click image for larger version

Name:	Load Calc image.JPG
Views:	3
Size:	152.5 KB
ID:	305015
__________________
2020 GMC Denali 2500HD Crew 4X4 Gas 6.6L Rockwood 8280WS (30' 5th)
1000W solar; 322AH LFP battery,
900W PSW inverter, NovaKool RFU9000 fridge
hclarkx is offline   Reply With Quote
Reply

Tags
lifepo4, solar



Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools Search this Thread
Search this Thread:

Advanced Search
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


Similar Threads
Thread Thread Starter Forum Replies Last Post
And from the solar panels to the solar charge controller...... Rvlegaleagle Going Green 10 10-20-2017 02:57 PM
Adding inverter, faster charge, solar, LiFePO4 battery K6NCX RV Systems & Appliances 8 06-15-2017 10:40 PM
Why so few LIFEPo4 batteries in RV? Loic Technology: Internet, TV, Satellite, Cell Phones, etc. 49 09-21-2015 10:43 PM
Travato LiFePO4 Battery Install wincrasher Class B Motorhome Discussions 1 07-28-2015 09:35 PM


All times are GMT -6. The time now is 09:22 AM.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2020, vBulletin Solutions, Inc.