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Lifpo4 questions for newbie

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JPetronek

New Member
Joined
Dec 2, 2019
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Morning all,

I am reading through a lot of your threads on different lifpo batteries and the question came to mind for someone that camps all year in temps from 80-90 degrees and down into the 5-15 degree nights in winter would lifpo be a good choiceor not with the cold temp cutoff? The problem I could see is typical morning, inverter running at night for tv and electric blanket, get up make pot of coffee and batteries are pretty well dead after that and furnace running all night, now I can’t charge since it’s below freezing??? Would I be better going with a vmax type battery?
 
Jay2020 said:
You could get a military arctic sleeping bag ( at army surplus stores or craigslist) , good for -40sh ( minus fortyish) , plus a little office leg heater that uses 50 watts.

These may cut your electrical usage.
Click to expand...
So in order to not give up the luxuries what your saying is LA, gel or SLA is what I should go with? Currently using LA and it works, just want to upgrade this spring/summer.
 
MisterSandals said:
Can you heat your batteries somehow with this furnace?

The big question is how much power you are actually using with your tv, electric blanket, furnace and coffee maker. That sounds like a LOT of luxury power use for camping.
Click to expand...
They actually aren’t to bad overnight, I have to check it accurately once I get my monitor installed. I know the tv is minimal, blankets typically get turned off half way through the night. I think my furnace is biggest draw, I’m not worried about the usage or capacity so much. Just wanting to upgrade to something I can use it’s full capacity if I need vs. half the capacity. Currently with heavy usage I’m guesstimating I dip into the 60% use area. Plus the way I look at it is I can replace my 3 LA batteries with 2 Lifpo’s and gain 1/3 more useable power with less weight and space.
 
MisterSandals said:
Can you heat your batteries somehow with this furnace?

The big question is how much power you are actually using with your tv, electric blanket, furnace and coffee maker. That sounds like a LOT of luxury power use for camping.
Click to expand...
To answer the question about heating the batteries, I currently could not without a lot of modifications and custom boxes. I never thought about it till you mentioned it, with the lifpo I could mount in the compartment since they don’t gas and keep them above freezing.
 
Jay2020 said:
No, just that there are things that can compliment, enhance, outdo...other things.

If warmth is what the electric blanket gives you, yet it uses electricity and you want to solve this electrical usage idea, then why not get a sleeping bag that is 1) durable/foreverish 2) exceptionally warm ( 2 layers for various coldnesses) 3) uses no electricity.

Just an opinion.

Good luck
Click to expand...
Appreciate the input, usage isn’t my issue as what I have now works well. Especially after I install my additional panels and new controller. Currently I only have one 160 watt panel and a 30 amp PWm that came w the trailer. Winter time I do have to use generator a few times to top off but it’s not the end of the world. I’m mainly looking for better more “durable” batteries over my cheap LA.
 
JPetronek said:
Morning all,

I am reading through a lot of your threads on different lifpo batteries and the question came to mind for someone that camps all year in temps from 80-90 degrees and down into the 5-15 degree nights in winter would lifpo be a good choiceor not with the cold temp cutoff? The problem I could see is typical morning, inverter running at night for tv and electric blanket, get up make pot of coffee and batteries are pretty well dead after that and furnace running all night, now I can’t charge since it’s below freezing??? Would I be better going with a vmax type battery?
Click to expand...

This isn't answering your question about batteries, but...for the sake of electricity reduction...
I was shown a diesel heater by@JeepHammer and this is what I will be installing in my rig - something like this: https://www.ebay.com/itm/4KW-Metal-Shell-12V-Diesel-Air-Heater-Thermostat-RV-Caravan-Trailer-Car-Boats-AA/133280449271?_trkparms=aid=555018&algo=PL.SIM&ao=1&asc=60695&meid=52f6dec96bfa4409a81ebe77a7321f94&pid=100005&rk=3&rkt=4&mehot=co&sd=391968549723&itm=133280449271&pmt=1&noa=0&pg=2047675&_trksid=p2047675.c100005.m1851

Also, have you tried a French Press for coffee? I use one now = no electricity needed, and taste's great! Just boil water with your gas stove which takes a couple minutes. (then wait 4 minutes). Cheers!
 
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All, while I appreciate the ideas on how to reduce my consumption that’s not what I’m looking for. I don’t care so much about my consumption. If my batteries get low I’ll start a generator. We are part timers that boondock a lot while riding in the woods or at the coast. I am starting to get into solar as it’s always intrigued me and fun to experiment with. I like gadgets and having neat stuff and pushing things to limit to know what it can do. I don’t live 24/7 in our trailer and budget doesn’t concern for fuel to run a generator for 4 hrs if need be to re-charge. We like our luxuries while camping because why not if we can. My question was simply about would lifpo batteries work if it was below freezing or should I stay with something else.
 
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Just size your batteries big enough to have enough reserve to run a battery heating pad for 2 hours before sun rise, maybe put it on a timer. I don't think you'll have to run it all night, just enough to get them warm internally before charging. Maybe install the batts in an insulated cooler so a small heater like those handlebar grip things can easily do the job and barely need to run. Or just stick with the LAs.
 
Jay2020 said:
I guess with all the " keep batteries warm"...one should create and sell a low wattage, heated fridgeish container.
Click to expand...

An old cooler makes a good cheap battery box. I've used them for boat batteries, with a small fan, to protect from the hot sun, but adding a simple heater would be easy for you northerners.
 
Jay2020 said:
I guess with all the " keep batteries warm"...one should create and sell a low wattage, heated fridgeish container.
Click to expand...

Amazon.com: ROCKPALS Car Fridge Electric Cooler and Warmer for Car, 32Quart Mini Fridge for Car and Home with Wheel&Pull Out Handle,12V DC 40Cans Portable Car Coolers for Road Trip, Camping,Truck Driver,Office,RV: Automotive

Buy ROCKPALS Car Fridge Electric Cooler and Warmer for Car, 32Quart Mini Fridge for Car and Home with Wheel&Pull Out Handle, 12V DC 40Cans Portable Car Coolers for Road Trip, Camping, Truck Driver, Office, RV: Coolers & Refrigerators - Amazon.com ✓ FREE DELIVERY possible on eligible purchases
www.amazon.com
 
I just bought a heated vest to wear that can double for battery warmers if NECESSARY that has a small battery itself. I just got one, so no actual hands-on experience with using it on batteries. I love dual-duty items. I don't plan on a lot of cold weather, but like to be prepared. Just throwing it out there. It is 50% off now.
 
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MisterSandals said:

Amazon.com: ROCKPALS Car Fridge Electric Cooler and Warmer for Car, 32Quart Mini Fridge for Car and Home with Wheel&Pull Out Handle,12V DC 40Cans Portable Car Coolers for Road Trip, Camping,Truck Driver,Office,RV: Automotive

Buy ROCKPALS Car Fridge Electric Cooler and Warmer for Car, 32Quart Mini Fridge for Car and Home with Wheel&Pull Out Handle, 12V DC 40Cans Portable Car Coolers for Road Trip, Camping, Truck Driver, Office, RV: Coolers & Refrigerators - Amazon.com ✓ FREE DELIVERY possible on eligible purchases
www.amazon.com
Click to expand...
Ha! The vest I was talking about is by the same maker, but I ordered direct.
 
Easy Option: Put your batteries in the heated space of your RV (This was mentioned earlier in the thread)

Unusual but still easy option:
Check the battery specs. Some of them allow charging down to 25F. Some are rated as low as 20 F. (The BattleBorn are rated for charging down to 25F) If that is what you have, throw one of these (Unfrozen) in an ice chest (Insulated box) with your batteries.
https://www.engelcoolers.com/engel-32-hard-shell-cooler-pak-large.html

1577043539435.png
If the inside of the ice chest gets to 32 deg, the freezer pack will start freezing. The phase change energy that is released as it freezes is quite large. Unless you are camping in very extreme cold, It would easily keep the chest at 32 deg or above over night.

Passive, easy, cheap and does not use up your battery.

Also, since you are using the heater, electric blankets, etc, the batteries are generating heat that would keep your insulated box warm. This makes it even less likely the batteries would ever get to their no-charge temp.
 
SolarRat said:
An old cooler makes a good cheap battery box. I've used them for boat batteries, with a small fan, to protect from the hot sun, but adding a simple heater would be easy for you northerners.
Click to expand...
Would you cut a hole in the lid for a fan like a computer fan? What kind of heater?
 
Santa said:
Would you cut a hole in the lid for a fan like a computer fan? What kind of heater?
Click to expand...
It seems to me that cutting a hole in the box defeats the purpose of using an insulated box. Furthermore, wouldn't you need two holes: Intake and exhaust. That would pretty much destroy the value of the insulation. However, you make a very good point. If the weather starts getting hot, do you need to worry about over-temp for the batteries? LiFePo4 can function at a fairly high temp (120F) so unless you are driving your batteries hard you may be ok in normal conditions. However, cooler is better so it is probably best to leave the ice chest open unless you are likely to get into freezing conditions.

If you do decide to cut holes in the box, at least do some kind of flapper vents to limit the air flow when the fan is not running. Ideally, the vent holes would have insulated covers that automagically deploy in when it starts getting too cool. That feels more complicated than I like, but it might be a fun project.
 
Santa said:
This isn't answering your question about batteries, but...for the sake of electricity reduction...
I was shown a diesel heater by@JeepHammer and this is what I will be installing in my rig - something like this: https://www.ebay.com/itm/4KW-Metal-Shell-12V-Diesel-Air-Heater-Thermostat-RV-Caravan-Trailer-Car-Boats-AA/133280449271?_trkparms=aid=555018&algo=PL.SIM&ao=1&asc=60695&meid=52f6dec96bfa4409a81ebe77a7321f94&pid=100005&rk=3&rkt=4&mehot=co&sd=391968549723&itm=133280449271&pmt=1&noa=0&pg=2047675&_trksid=p2047675.c100005.m1851

Also, have you tried a French Press for coffee? I use one now = no electricity needed, and taste's great! Just boil water with your gas stove which takes a couple minutes. (then wait 4 minutes). Cheers!
Click to expand...

I have the 5KW version of that heater for my RV and it keeps it very warm ... these are easy to install and easy to use .. maintenance all depends on how trashy the diesel is your using .. use clean fuel and there is very little maintenance .. there is an entire Facebook forum on just these ...
 
ghostwriter66 said:
I have the 5KW version of that heater for my RV and it keeps it very warm ... these are easy to install and easy to use .. maintenance all depends on how trashy the diesel is your using .. use clean fuel and there is very little maintenance .. there is an entire Facebook forum on just these ...
Click to expand...
Great! The OP doesn't want any more electrical reduction suggestions, but thank you for telling us this! (I am happy to hear this!)
 
Santa said:
Would you cut a hole in the lid for a fan like a computer fan? What kind of heater?
Click to expand...

I wouldn't cut any holes if you want to use it for heating too. For the hot weather I just put holes on both sides and cover them with louvers from a cut up HVAC register to keep out the rain, and install the fan inside blowing out one of the holes. It's more to just keep airflow going, especially when the batteries are heating up under load and the cooler is in the hot sun. Mine were FLA's so venting was necessary anyway.

For heat, the lowest draw heater you could find would probably keep the cooler above freezing in normal camping type weather. A 5-10w incandescent bulb would probably work in a pinch, but there are much better solutions of course.
 
SolarRat said:
I wouldn't cut any holes if you want to use it for heating too. For the hot weather I just put holes on both sides and cover them with louvers from a cut up HVAC register to keep out the rain, and install the fan inside blowing out one of the holes. It's more to just keep airflow going, especially when the batteries are heating up under load and the cooler is in the hot sun. Mine were FLA's so venting was necessary anyway.

For heat, the lowest draw heater you could find would probably keep the cooler above freezing in normal camping type weather. A 5-10w incandescent bulb would probably work in a pinch, but there are much better solutions of course.
Click to expand...
Nice! Aren't the incandescent bulbs "legal" again?
 
Santa said:
Nice! Aren't the incandescent bulbs "legal" again?
Click to expand...

They were always available, but I was talking about the tiny DC bulbs like for car dome lights. We used to throw an AC 100w bulb in the engine room of our boats as a "heater" to keep on boating later into the winter without the engine freezing up. Again I don't recommend it, but ya gotta do what ya gotta do.
 
Santa said:
These were suggested to me by another member on a thread of mine to keep Lithium batteries from freezing. I haven't tried them, but will. https://www.ebay.com/itm/US-Motorcy...Hand-Warmer-Adhesive-Heated-Pads/153731190523 Obviously you know you can buy battery heating pads. This is just a cheaper (less power) alternative...if you have the money, buy the heating pads for the batteries? EDITED: https://battlebornbatteries.com/shop/heat-pad-for-bb10012/
Click to expand...
I was wondering about these, most are 15 watts each. Wonder how well it would actually work. Could easily run them off a thermostat
 
SolarRat said:
Just size your batteries big enough to have enough reserve to run a battery heating pad for 2 hours before sun rise, maybe put it on a timer. I don't think you'll have to run it all night, just enough to get them warm internally before charging. Maybe install the batts in an insulated cooler so a small heater like those handlebar grip things can easily do the job and barely need to run. Or just stick with the LAs.
Click to expand...
That’s not a bad idea on the timer. I think if I go lifpo I’ll mount in compartment. It would shorten up wire runs to inverter also. Just hate giving up space.
 
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