Cheap lithium

[DanK]

With all the cheaper lithium battery options available I'm looking for advice from anyone who has gone that route . I'm seeing on Amazon a variety of brands in the $300 to $500 dollar range . Does anyone use these and if so what is your experience with them

[Ron in BC]

I'm not sure what brands you're looking at but I've bought two Renogy batteries because the prices were good and they actually have customer service. I'm not so sure what type of customer service some of the other cheaper brands have.

Ron

[WanderBred]

I hear SOK batteries are good.

[alanmalk]

I snagged a pair of 100 AH Renogy lithium's on Ebay last fall for $400 each. I don't have any real world experience with them yet, but looking closely at the specs reveals that they don't have an internal (BMS) cold temperature cutoff. I have not seen very many of the sub-$500 lithiums with this feature. In reality not having this feature means I can't float the batteries (on solar) in winter when the trailer is unattended. While camping I fully expect the batteries to be warm and cozy - like I intend to be - so the missing low temperature cutoff is not needed.

[Effie]

Originally Posted by alanmalk

I snagged a pair of 100 AH Renogy lithium's on Ebay last fall for $400 each. I don't have any real world experience with them yet, but looking closely at the specs reveals that they don't have an internal (BMS) cold temperature cutoff. I have not seen very many of the sub-$500 lithiums with this feature. In reality not having this feature means I can't float the batteries (on solar) in winter when the trailer is unattended. While camping I fully expect the batteries to be warm and cozy - like I intend to be - so the missing low temperature cutoff is not needed.

The Renogy batteries actually have low temp protection, below is a link to the manual

https://www.renogy.com/content/RBT10...00S-Manual.pdf

[Vermilye]

Originally Posted by alanmalk

I snagged a pair of 100 AH Renogy lithium's on Ebay last fall for $400 each. I don't have any real world experience with them yet, but looking closely at the specs reveals that they don't have an internal (BMS) cold temperature cutoff. I have not seen very many of the sub-$500 lithiums with this feature. In reality not having this feature means I can't float the batteries (on solar) in winter when the trailer is unattended. While camping I fully expect the batteries to be warm and cozy - like I intend to be - so the missing low temperature cutoff is not needed.

If you are using a Victron solar controller combined with one of their battery monitors, you can add a temperature probe, network the controller & monitor, and set a low temperature cutoff for the solar controller.

[alanmalk]

Originally Posted by Effie

The Renogy batteries actually have low temp protection, below is a link to the manual

https://www.renogy.com/content/RBT10...00S-Manual.pdf

I stand corrected. It appears to have a low temperature protection mode. But per the fine print I am still not within the requirements unless I can disconnect the solar. The trailer will be in storage while not being used and not always accessible when the weather requires.
"If the battery temperature gets too high/low during the operation and triggers the battery high/low temperature protection, please disconnect the battery from the charging source and electric loads and cool down/warm up the battery to room temperature. The battery will automatically recover from the battery high/low temperature protection."

I see Jon has a high-tech solution!
(But the title of this thread is "Cheap...".)

[hugh]

Not sure if you'd want to go this route, but I decided that I'd give the "DIY" option a try. It amounts to buying the individual cells and a BMS board, and buying or building a case.

I've purchased 16 230Ah LifePo4 cells, which I'll be building into two 24V battery packs. That gives me around 11.7KWh, or the equivalent of eight 100Ah battleborns. The total cost for the cells was around $1800, and around $300 for the BMS and case. So, around $0.18/KWh.

That's around the same price as the cheaper LifePO4 options on Amazon, but with several main advantages:
* Low temperature protection
* Smart BMS with individual cell monitoring via Bluetooth, RS-485 interface
* Active cell balancing
* 40%-50% less weight per KWh than typical lower end LifePO4 batteries
* Grade A cells

The down side is that you've actually got to take the time to order the parts and assemble them, and obviously not much in the way of a warranty. (Although I'm guessing warranty support from the lower end offerings probably isn't worth much anyway).

Here's a picture of the cells that I bought. I'm waiting for the BMS boards to arrive before putting things together.

[gklott]

Originally Posted by DanK

With all the cheaper lithium battery options available I'm looking for advice from anyone who has gone that route . I'm seeing on Amazon a variety of brands in the $300 to $500 dollar range . Does anyone use these and if so what is your experience with them

Most of these cheaper LiFePO4 batteries are not UL, ETL, or other nationally recognized testing laboratory (NRTL) certified. Carefully check the battery details.

For example, Battleborn batteries are UL 2054 listed. UL 1642 (Lithium Batteries) is the standard used for testing lithium cells, and lithium battery level tests are covered by UL 2054. Lithionics goes one step further having achieved the UL 1973 certification for "Batteries for Use in Stationary, Vehicle Auxiliary Power and Light Electric Rail (LER) Applications".

QAI (Canada) and RVIA (US) require using "listed" products in all new RVs. While you are not required to do the same, I highly recommend you consider continuing that for any major trailer infrastructure system changes you make; electrical, plumbing, propane, etc.

73/gus

[Brian B-P]

Originally Posted by hugh

...That gives me around 11.7KWh, or the equivalent of eight 100Ah battleborns. The total cost for the cells was around $1800, and around $300 for the BMS and case. So, around $0.18/KWh.

That's $0.18/Wh, or $180/kWh (just a typo)

[hugh]

Originally Posted by gklott

Most of these cheaper LiFePO4 batteries are not UL, ETL, or other nationally recognized testing laboratory (NRTL) certified. Carefully check the battery details.

For example, Battleborn batteries are UL 2054 listed. UL 1642 (Lithium Batteries) is the standard used for testing lithium cells, and lithium battery level tests are covered by UL 2054. Lithionics goes one step further having achieved the UL 1973 certification for "Batteries for Use in Stationary, Vehicle Auxiliary Power and Light Electric Rail (LER) Applications".

QAI (Canada) and RVIA (US) require using "listed" products in all new RVs. While you are not required to do the same, I highly recommend you consider continuing that for any major trailer infrastructure system changes you make; electrical, plumbing, propane, etc.

73/gus

Yep, that's a good point. From a "total risk" perspective, it's also important to consider the installation. UL listed alone doesn't mitigate inadequate fusing, loose or incorrect wiring, leaking gas lines, etc. In many cases, it might just be better to leave the modifications to the pros.

[hugh]

Originally Posted by Brian B-P

That's $0.18/Wh, or $180/kWh (just a typo)

Hahah, thanks! $0.18/KWH would be quite something.

[Ron in BC]

Originally Posted by hugh

Yep, that's a good point. From a "total risk" perspective, it's also important to consider the installation. UL listed alone doesn't mitigate inadequate fusing, loose or incorrect wiring, leaking gas lines, etc. In many cases, it might just be better to leave the modifications to the pros.

Actually, over the years, I really haven't seen any evidence that folks doing mods on their trailers have created any problems for themselves.

Most approach mods involving propane or electrical etc. quite cautiously and most often ask the forum for advice if they're unsure.

Ron

[Eggscape]

I would never buy a battery that Will Prowes has not taken apart.

He has taken apart many batteries to find what they say on the label may not be what is inside.

Here is a link to one of his videos...if you are serious about buying a battery, subscribe and watch all of his videos.

https://youtu.be/pKFh7eXeY-s

[Brian B-P]

Originally Posted by Ron in BC

Actually, over the years, I really haven't seen any evidence that folks doing mods on their trailers have created any problems for themselves.

Most approach mods involving propane or electrical etc. quite cautiously and most often ask the forum for advice if they're unsure.

I suspect that people who consult others through a forum are likely on the carefully and cautious side There are others who do create problems, all by themselves; their messes only appear on a forum when someone else buys the trailer and posts "look what I found". The worst stuff is done to cheap old trailers, and even the earliest Escapes are not very old and are still not cheap.

[John in Santa Cruz]

Originally Posted by WanderBred

I hear SOK batteries are good.

I have installed a pair of their 12V 206AH batts that were $1029 each (rumor has it soon to go up), this provides 5200 watt*hours.

the build quality on these batteries is excellent, I got them through a US distributor, currentconected, and they seem to offer excellent aftermarket support. they have a 7 year warranty, and are built from grade A cells from one of the better cell vendors. Two of them nicely fit under the curbside dinette bench on my E21 classic.

this was work in process.



here, they are temporarily sitting where the original dual golf cart battery box was.

but thats now all additional useful storage space since I relocated them to the back corner.

[Sean Murry]

Originally Posted by alanmalk

I snagged a pair of 100 AH Renogy lithium's on Ebay last fall for $400 each. I don't have any real world experience with them yet, but looking closely at the specs reveals that they don't have an internal (BMS) cold temperature cutoff. I have not seen very many of the sub-$500 lithiums with this feature. In reality not having this feature means I can't float the batteries (on solar) in winter when the trailer is unattended. While camping I fully expect the batteries to be warm and cozy - like I intend to be - so the missing low temperature cutoff is not needed.

Your batteries might be different, but I have 4x100A Battle Born Lithium batteries. Battle Born recommends you disconnect the batteries while in storage. Not just the battery isolator switch, but disconnect the batteries completely so the solar charger doesn't continue to charge. They say it is good to let the batteries rest when not in use. They also suggest the batteries be at about 80% charge when put into storage. Because Lithium loses very little power while be stored, when you go to hook up you should still have lots of power available

[John in Santa Cruz]

that 80% is not a hard number, long term storage for Lithium-Iron-Phosphate batteries is best if its anywhere between 20-80%.

If I know this current trip is going to be the last for several months, my plan is to shut off the AC converter and the solar panel several days before the end of the trip, or if I forget, do that when I get home, and leave the fridge running for a week or so to run them down to about 50%... then shut everything off, but I'm not going to be actually disconnecting the batteries, they will remain paralleled, and the propane detector will remain powered.

[Sean Murry]

You are right about the 80% storage level not being a hard number. I meant to say Battle Born recommended storage not above 80%

[Sean Murry]

Disconnecting the solar panel versus disconnecting the batteries makes a lot of sense. Bottom line is Battle Born is suggesting no charging of the batteries while in storage to give them their "rest"