AGM or LiFePo4?

[Anhedonic]

Would this be a good battery to use in my SUV to set up for house-type plugins?
https://www.amazon.com/EarthX-ETX12...d=1538508806&sr=8-10&keywords=LiFePo4+battery

I would not expect that this would be a good battery to use for that purpose. It does not list a capacity, only talking about cranking amps so I'm guessing this is primarily meant to be used as a starter battery rather than for deep cycle applications. Also, based on the weight and the price, I would guess the capacity to be quite low.

 

[Anhedonic]

Yes drop-ins are "easier" in some ways, and treated properly may last a long time.

But they are very limited performance compared to a proper system built on 4S prismatic cells, which for sure will last **much** longer if cared for properly.

5x the cost is a very low estimate, and it is possible to kill them dead pretty easily.

Compare to Deka, quality deep cycle FLA at $1 per AH. Much better value, can last 8+ years cared for properly.

Double the weight though.

My perception of the OP tech knowledge, recommend sticking to lead, but might mean getting a bigger / stronger vehicle.

A really good LFP bank that big will cost many thousands.

I don't feel confident building a bank out of 4 cells. Getting a bigger/stronger vehicle is really not an option at this point. I was thinking about one of these which came up in discussion of LFP batteries:
 https://www.altestore.com/store/dee...ault-lithium-solar-battery-p41011/#KLV3600HLX

Basically, this would be my only battery, probably for the length of time I own this van.

 

[QinReno]

 https://www.altestore.com/store/dee...ault-lithium-solar-battery-p41011/#KLV3600HLX

$1300 is pretty expensive for just 150-AH. What are you planning to run off that amount of power? Lights, frig, or whatever else.

 

[Anhedonic]

$1300 is pretty expensive for just 150-AH. What are you planning to run off that amount of power? Lights, frig, or whatever else.

I was thinking about the bigger one.

 

[QinReno]

Ahh, so. 300-AH (at $2300) will be a better size for running the usual conveniences. I have 100-AH now and just run lighting and laptop, but figure I'd need to go to at least 300-AH to add frig and other kitchen items. Unless maybe guaranteed sun. A few days of cloudiness can make a big difference.

 

[lenny flank]

 They are known to catch fire, in certain cases.
- https://www.google.com/search?q=lithium+battery+on+fire

It's the lithium-ions that sometimes burn up. The lithium-irons are a different chemistry.

 

[QinReno]

It's the lithium-ions that sometimes burn up. The lithium-irons are a different chemistry.

Yeah, that's already been the object of repeated hammering and hammering, my head hurts, LOL.

Similarly, the 2 people in the youtube that was linked just say Li and Li Ion, whereas the quick passing reference to "battleborn" apparently referred to LiFePO4. I had to look it up, there were no links. So are these people complete idiots, or smart?
[font=Roboto, Arial, sans-serif]"This video is about AGM vs Lithium Ion Battery for Solar in a DIY Camper Van"[/font]
The horse's mouth: "We just changed all of our AGM batteries in our camper van to lithium batteries".

 

[max+sophia]

Could youse (I'm from NY :blush: ) experts check out this solar battery system at #118
https://vanlivingforum.com/showthread.php?tid=32239&page=12

 

[Anhedonic]

Could youse (I'm from NY :blush: ) experts check out this solar battery system at #118
https://vanlivingforum.com/showthread.php?tid=32239&page=12

I am hardly an expert, but I'll give you what I can. Those are some really small batteries with regard to capacity. The one from the first link is only like 23ah @ 12v. The second gives no rating for capacity, but everything in it talks about cranking power rather than deep cycle applications. I'm thinking that's probably just a lightweight starter battery replacement and also will not be suitable for use as a house battery, even for a home as small as Ruby.

 

[Anhedonic]

Could youse (I'm from NY :blush: ) experts check out this solar battery system at #118
https://vanlivingforum.com/showthread.php?tid=32239&page=12

The main one you mentioned there looks like a nice system, but only has a capacity of about 26ah @ 12v. Again, that's pretty small, but it might be workable if you're not running much. I mean like not running anything but chargers for your electronics and maybe some lights.

 

[QinReno]

Yeah, 26-AH for this unit is very low amount of energy storage.
- https://www.amazon.com/dp/B074P162XQ

A typical laptop will draw about 40W, or 40W/12V = 3.3A at 12VDC. Taking into account the loss in the 120VAC inverter, figure maybe 4A draw from the battery. Therefore, the laptop will pull the battery down to near 50% in about 3 hours.

A 60W equivalent 120VAC Led bulb actually draws 11W, or about 1-AH at 12VDC. So you could run just the 1 bulb for only about 10-12 hours before the battery dropped to 50%.

 

[Anhedonic]

So, from all who have chimed in, it sounds like the takeaway is that LFP is the way to go if you can afford it because the increased lifespan and deeper cycling ability makes it long-term economical if somewhat more complex to construct. It certainly is in line with what I have read on the topic.

Is that about the size of it?

That leads to the next question. Has anyone created a master list of all the pieces one might need to construct a systems?

I mean you need either 4 cells put together to make a 12v battery or you need a pre-constructed one. You also need a charge controller to handle charging from solar, a separate charge controller to act as an intermediary between the alternator and the battery and a charger to deal with charging from an AC source. You need a way to monitor charge more closely than can be done by voltage alone.

What else do you need? A list of things one needs with examples would be possibly the most helpful thing I can think of. I have found similar lists for AGM setups. Is there one for lithium? Or possibly a list of things that must be changed for a lithium setup?

 

[Knit]

AM solar has some interesting packages of batteries/solar/inverters/etc. including pricing at https://amsolar.com/products/solar-van-conversions/

They ave both AGM and Li packages. Their least expensive Li package at the link is over twice as expensive.

 

[Anhedonic]

AM solar has some interesting packages of batteries/solar/inverters/etc. including pricing at https://amsolar.com/products/solar-van-conversions/

They ave both AGM and Li packages. Their least expensive Li package at the link is over twice as expensive.

I looked at the prices and boy howdy that's expensive! 

Still, it looks like a very useful resource for just what I was asking for, a list of all the things needed. Thank you.

It does remain unclear about exactly what you get for which system but it will certainly help

 

[QinReno]

I looked at the prices and boy howdy that's expensive! 

That's what I thought when looking at the LFP batteries you referenced! Is it even worth while messing with at those prices.

...
I mean you need either 4 cells put together to make a 12v battery or you need a pre-constructed one. You also need a charge controller to handle charging from solar,

Where did this business come from about "4 cells put together"? Certainly you're not gonna do that with pre-assembled 12V units available. You will notice the ones you mentioned have a "[font=PTSansRegular, arial, serif]Battery Management System[/font]" built-in.
"[font=PTSansRegular, arial, serif]Monitors and optimizes charge & discharge for each cell, provides overcharge, over discharge, temperature and short circuit protection".[/font]

That's to balance charging on the different internal cells. You would have to build this yourself. FWIW, it's very common with NiMH series packs (eg 6/ea --> 7.2V, and which do not use balanced charging) that one cell will loose efficiency and the other cells will "force" it into total discharge or even reverse-charge. So with Lithium it's apparently even more important to balance the cells internally.

Re 2nd question, these controllers indicate they'll handle AGM or Li. I assume this is so because the Li batteries have the built-in battery management system.
- https://www.amazon.com/Renogy-Adventurer-Charge-Controller-Compatible/dp/B07BBKFTNV
- https://www.amazon.com/dp/B078VL7HGY

 

[highdesertranger]

it's said that most people ruin their first battery bank. I would sure hate to ruin a bank of Lithium batteries. highdesertranger

 

[Anhedonic]

it's said that most people ruin their first battery bank.  I would sure hate to ruin a bank of Lithium batteries.  highdesertranger

I wholeheartedly agree with you there. I've read quite a lot that, as long as you stay within temperature and charging tolerances, that the LFP batteries with internal BMS are pretty hard to hurt. It looks to me like they're not a touchy as the lead acid batteries. I could be mistaken, but that's my impression. I mean assuming you don't do anything stupid or crazy like physically breaking them or shorting them.

 

[max+sophia]

The one (battery) from the first link is only like 23ah @ 12v. The second gives no rating for capacity, but everything in it talks about cranking power rather than deep cycle applications. I'm thinking that's probably just a lightweight starter battery replacement and also will not be suitable for use as a house battery, even for a home as small as Ruby.

Anh, What numbers should I be looking for?  The system is not just for Ruby.  I need to be able to run an oil boiler when the electric goes down.  The electric kettle I'd like is 1500w

 

[John61CT]

It's the lithium-ions that sometimes burn up. The lithium-irons are a different chemistry.

Lithium is equivalent to lithium-ion, same umbrella category.

NMC, LiPo, LCO, NMA are some non-LFP examples

 

[John61CT]

Ahh, so. 300-AH (at $2300) will be a better size for running the usual conveniences. I have 100-AH now and just run lighting and laptop, but figure I'd need to go to at least 300-AH to add frig and other kitchen items. Unless maybe guaranteed sun. A few days of cloudiness can make a big difference.

So if that's all you need, a grand total of $400 will get you a decent quality ~500AH bank, much easier to keep alive, if you go with drop-in IMO may even last longer.