LifePo4 Lithium Iron Phosphate Battery

Hi All;
As some of you may know I've been off the electric grid since 1983.
Over the years I have tried most styles of battery that were /are available.
Lead Acid , Nickle iron , Nickle Cadmium , AGM.
As we all know each style  has its  pro's and cons.
I finally settled on sticking with lead acid.
I  used 4  L-16  battery's. Not Cheap
Then in the middle 1990's I developed water power.
6-14 amps @ 12 vt  24 seven .
I dropped  from 4 L-16's down to two.
I also learned how easy it is to run your battery low on water... effectively killing cells...
Five years ago I tried AGM battery's.
I went with 230 amp hr set.
Even though I did not run them low on water, after five years they are now shot.

Our power usage is low.
With the hydro running all the time @ 120 + watts  and 530 watts of solar anytime the sun is shining.
My battery's rarely see more than 50-80 amp hrs against them before we shut off the inverters for the night.
Highest load we put against them temporarily is in the 70 amp range.

I use a Tristar 45  constant diversion charge control.
A small 600 watt Cotek pure sine inverter and a Magnum 2000 watt  pure sine inverter.
A trimetric  power monitor as well as the Magnum monitor.  

I have been watching and waiting on new battery technology.
The LifePo4  lithium iron phosphate battery seems to be the clear winner at this time...
Of course AFTER I buy, then some new better battery will appear...

Here is a link to the LifePo4  that I am planning on purchasing.
https://www.us.sokbattery.com/product-page/12v-206ah-lifepo4-lithium-iron-phosphate-battery-pack

SOK  206 amp hr  12 volt battery.
I'm thinking that dropping from 230 amp hr down to 206 is an acceptable reduction.
Buying  two of the 206 hr battery's is an expensive option. It would  give me 412 amp hrs but ???
Do I need that much?

Anyone got  thoughts or opinions ?

so i just bought a renogy 12v 100ah battery based on will prowse youtube review/tear down of the battery. It cost me 700 Canadian to get it shipped to my door.

I am hearing that LIPO4 is quite safe for installation inside buildings. I believe the fire concern is related to the other chemistry of lithium.

Here is what i suggest you look at on youtube. I also recommend him to other permies for anything solar related. The forum he operates is also very helpful.

here is the channel https://www.youtube.com/c/WillProwse/search?query=sok


I would have bought the sok battery had it not been for finding the slightly cheaper renogy battery.


so if you have had 230ah with lead acid. Which only about 50% of that is usable due to how lead acid functions. So you basically have 115ah battery with the lead acid.

With the 206ah of Lipo4 i believe about 80% of the battery is usable. Meaning you would have 164.8 ah of battery use.  Along with a 7 year warranty.

One thing to consider thomas is whether your current charge controller can charge lithium batteries, it might not have the option.


I found this article which describes someone getting there morning star ts 45 to work with a lipo battery. https://senormisterioso.wordpress.com/2017/09/22/programming-a-morningstar-ts-45-to-work-with-battle-born-lipo4-batteries/

Thomas,

So, so interesting.

I am involved in a project that uses  LiFePo4 battery.  Originally it was going to be a SLA battery but I opted to try to get around the Peukert effect.  It makes the build a LOT more complicated but it is a fun project.  It will be interesting to see how my little 20 amp hour LiFePo4 battery works out.  I may add to this in the future if I get really ambitious.

Eric

I am also using a tristar for my hydro dump controller with lithium batteries - mine are Simpliphi brand. The Tristar is programmable, but needs a cable and a computer program to change the settings. My understanding is that all the LFP cells come from the same place (hint; it is China). Some of the modules are manufactured in the US, but it seems like in general they all tend to be pretty good. You can actually get the unpackaged cells, and I believe it could save a few bucks that way - but - then you need to figure out the BMS on your own or periodically check that they are all balanced. Its probably better to get them packaged into modules unless you really want to learn more about the inner workings of a lithium battery pack.

These are the batteries I got a couple years ago:
https://www.solar-electric.com/simpliphi-phi-3-5kwh-24v-lithium-ferro-phosphate-battery.html?msclkid=66cc90f9cbfa19bbe0bbf2e8977c6599&utm_source=bing&utm_medium=cpc&utm_campaign=Shopping%20-%20All%20Products&utm_term=4588536901185459&utm_content=All%20Products

I am jealous that your hydro runs all year, by the way. My stream drops to a trickle in the summer here, so I can only count on power between about December and April. At some point I am going to build a waterwheel for the bigger creek... If I could get a 3' dam on it, I would have more power than I would know what to do with!

Thank You Guys!
This is exactly the information that I needed.
I was not aware about my charge control needing adjusting!
Thanks to Jordan's youtube link, I know what cable to order and how to find the info I need!
Carl; I may PM you at a later date, for details on the settings you ended up using with your Tristar.

Lithium batteries do not use the same charge voltages, so you risk overcharging them if you use gear that is only suitable for lead acids. Also, you dont need an absorb cycle, and of course, they will never need to be equalized. Lithium wants to be charged at constant current until they reach a certain voltage, and then held at constant voltage until the current tapers off to nothing, This is why when you plug in a lithium tool battery, for example, it will quickly get to 80%, then slows way down as the charger gets it to 100%.

On a bank of house batteries, with hydro power available 24/7, you will probably want to set your parameters to leave them slightly shy of full charge. Unlike lead, lithium does not want to be kept at 100%, and will give you the most lifespan if cycled between 30% and 70%. Still, it is a very robust battery chemistry, and should in theory last for a really long time even with 80% DOD cycles.

Carl,

Thanks for the input.  I was able to set up the charge controller by temporarily powering it with my other battery box.  I powered it just long enough to get it set up for a lithium battery after which I disconnected the charge controller.  I should have a dedicated wall wart LiFePo4 charger tomorrow after which I can bring the battery back up to a more appropriate voltage.

Eric

We have two ampere-time 12v 300ah batteries for the main battery bank; great company, great service, free return/swaps, etc.

We also have two SOK 12v 100ah batteries for smaller projects; SOK is responsive, but periodically inventory-challenged, and I have not tested their return capability.

I think both A-T and SOK are great companies, if you are not building your own; because of my warranty experience and their availability, I lean towards AmpereTime. I will add two more A-T 300ah's this year, once I sort out the parallel stuff.

Used to be on Rolls-Surette FLA's, but the maintenance (& weight) ate me alive; we only got upwards of 50% out of those R-S ah's, and never could hit 1000's of cycles. We routinely get 90% or more out of the A-T's, and expect to get 1000's of cycles out of them ... and they take up a fraction of the size of the FLA's. They've been running a year now; SOK's have been running a year now. ZERO maintenance on either one ...

LiFePO4 is good stuff ... if it lasts us upwards of 7 years, or 1000's of cycles, it's already both better than what came before, and will hold it's own against future tech.

Hope this helps ...

530W of solar?  That is your problem.  Right now today, I have 5500W on-line.  Stop shopping online and look on Craigslist for local deals.  Most of the cost is shipping, so if you shop locally, with local pickup, you save a massive amount of money.  I just bought another 1500W just three weeks ago.  260W REC panels for 65$ each.  So I payed just 390$ for 3 times the amount of your whole system.  I did have to drive a 1/2 hour out of my way to pick them up, but for a deal like that, what's an extra 3 gallons of gas?  I also have Rolls Surrette.  What maintainance are you talking about.  I add distilled water every two months, but other than that, nothing.  The biggest problem with lead-acid batteries is chronic undercharging.  Feed them what they need and they will feed back to you for many years.

Thomas, everyone,

My project ran into a brick wall—my battery has a bad cell, as in 3 of the 4 charge up just fine but 1 just won’t charge at all.  And unfortunately my battery is past the return period/out of warranty.  Given the expense of LiFePo4 batteries, it may be prudent to figure out how these batteries behave by buying a smallish one first and experimenting with it before buying a full sized one.

My project was supposed to be a 100ah SLA battery but I switched to LiFePo4 late.  I am using a $100 20AH LiFePo4 battery as opposed to a $200 to $300 100AH SLA battery, and a $100ah LiFePo4 battery would be expensive indeed.  My point is that though I am frustrated that I lost a $100 battery, I am certainly glad I was not spending $200-$1000.

In practical terms, owing to something called the peukert effect, a LiFePo4 battery will actually equate to a little better than twice that reading of an SLA battery, meaning my 20 AH LiFePo4 battery should roughly equate to a 45ish AH SLA battery.

To summarize a long and rambling post, it might be good to start small and affordable before making a large, expensive investment.

My 2 cents,

Eric

Eric, what brand of battery did you buy? And how long did it sit before you tried to use it?

LFP batteries have come down a lot in price in recent years, and this is really helping them gain some traction in the market. It does seem like reading reviews before you buy is a good idea, and also make a point of checking on the warranty that they offer. It seems like a good idea to buy from a reputable brand with good reviews, and that has at least some presence in the States. ALL the cells are being made in Asia, so even though some brands assemble the modules here in the states, all the basic materials are coming from the same place. A big outfit that is getting good quality cells, and shipping from the US might not be the cheapest option out there, but it will likely be more reliable.

thomas rubino wrote:Hi All;
As some of you may know I've been off the electric grid since 1983.
Over the years I have tried most styles of battery that were /are available.
Lead Acid , Nickle iron , Nickle Cadmium , AGM.
As we all know each style  has its  pro's and cons.
I finally settled on sticking with lead acid.
I  used 4  L-16  battery's. Not Cheap
Then in the middle 1990's I developed water power.
6-14 amps @ 12 vt  24 seven .
I dropped  from 4 L-16's down to two.
I also learned how easy it is to run your battery low on water... effectively killing cells...
Five years ago I tried AGM battery's.
I went with 230 amp hr set.
Even though I did not run them low on water, after five years they are now shot.

Our power usage is low.
With the hydro running all the time @ 120 + watts  and 530 watts of solar anytime the sun is shining.
My battery's rarely see more than 50-80 amp hrs against them before we shut off the inverters for the night.
Highest load we put against them temporarily is in the 70 amp range.

I use a Tristar 45  constant diversion charge control.
A small 600 watt Cotek pure sine inverter and a Magnum 2000 watt  pure sine inverter.
A trimetric  power monitor as well as the Magnum monitor.  

I have been watching and waiting on new battery technology.
The LifePo4  lithium iron phosphate battery seems to be the clear winner at this time...
Of course AFTER I buy, then some new better battery will appear...

Here is a link to the LifePo4  that I am planning on purchasing.
https://www.us.sokbattery.com/product-page/12v-206ah-lifepo4-lithium-iron-phosphate-battery-pack

SOK  206 amp hr  12 volt battery.
I'm thinking that dropping from 230 amp hr down to 206 is an acceptable reduction.
Buying  two of the 206 hr battery's is an expensive option. It would  give me 412 amp hrs but ???
Do I need that much?

Anyone got  thoughts or opinions ?

Definitely go with LiFePo4 batteries! Can't say if the particular batteries you have in mind are good ones though. I just don't know
Also, here's a forum I recommend. I had no background in solar, but really learned a lot from asking questions and interacting with this community:
https://diysolarforum.com/
People on there will probably know about the batteries you're asking about.

Carl,

Definitely good points.  The brand is ECI power that I bought through Amazon.  It had mostly good reviews with some bad ones--same as every other battery I checked.  It had sat for about 1 month before I used it.  It did seem to work under extremely light loads   I just ordered another battery.  The same one, but this time with a 4 year warranty for another $13.  Seems prudent given my experience with the first one.

Eric

I used an home ESS solar power storage LFP battery at home, it can storage power from the Grid without solar power also, dual ways charging the battery.

I just thought I would add that my second battery is working just fine.  My battery generator project is about 85-90% finished but stalled for the moment.  My next step is to calibrate my battery monitor and then figure out what I want to do for AC power.  My little 20AH battery is just a relatively cheap one that I thought I would use to get the project started.  Realistically I want to get one that is at least 50 AH and preferably 100AH or even higher.

Eric

Thread re-boot with an eye on locomotion.....

I just pulled 6 ~200 Ah FLA batteries out of my golf cart that we use as a farm buggy.  As an ageing homesteader, you can appreciate how much fun that was... :-/

The draw of LiFePO4 is clear from the news of their weight (~1/3 that of lead acid), power curve, and high cycle number.  But I'm seeing some additional factors in using this platform that I hoped to get additional info on from the Permies angle.  First, it seems that there is some controversy about using strings of LiFePO4 batteries in series vs. parallel connection configuration??...  Many golf carts of 36 and 48V used multiple 6V deep cycle FLA batteries in series to reach the proper voltage.  Is there a reason this does not work the same way with LiFePO4 batteries?  The trend that I'm seeing seems to purchase individual LiFePO4 batteries of the desire voltage at the beginning and then string them in parallel to reach the Ah needs of the system.  I've also seen that some battery monitors that are capable of reading LiFePO4 batteries can function on no more than 2 series-connected batteries at a time.  Is this correct?  *If* I can still get by with multiple 12V LiFePO4 batteries connected in series to meet my needs, I would hope to be able to find a state-of-charge meter that could read the full bank.....it's easy enough to check the individual batteries with a multimeter.  Finally, as I'm aware that the best charging of a LiFePO4 battery or bank is done with a dedicated LiFePO4 charger, there nevertheless seems to be concerns about even such a charger working on a series-connected string of LiFePO4 batteries....about potential charge imbalance between the batteries.

Really would like to make the switch over to Lithium for this golf cart system and hope there are some answers here to help me along the way.  Thanks!

John,

Something worth considering, and worthy of consideration for the OP as well is the possibility of building your own battery.  By this I mean that you buy individual cells plus a battery monitor and connect them all together.  This can be a better/cheaper option than buying an individual battery.

In the topic of stringing LiFePo4 batteries together, it can certainly be done—and in some cases is almost necessary.  LiFePo4 batteries are excellent batteries—lots of energy, many charge/discharge cycles, stable & safe, relatively lightweight—but they have one big drawback.  LiFePo4 batteries have a low “C” rating, which is a measure of how much power the battery can give off at any one moment.  An SLA battery might be able to give a 5-6 or higher “C” rating.  Lithium Ion is even better.  But LiFePo4 is a mere 1.  C is simply a multiple of the amp hour rating.  A 20 AH SLA battery with a 5 C rating can give up to 100 amps of current at any one moment.  A similar 20 AH LiFePo4 battery can only give up 20 amps at any one moment.

Where I am going with all of this is that you can still get to say 100 amps discharge, but you will need 5 times more cells.  This can be done with certain kits, but check the BMS for its specs first.

Hope this helps,

Eric

Just note that you shouldn't charge those batteries when the temperature is below freezing.

Thanks for these helpful responses and I hope Thomas R. as the OP is finding something of value here as well.

I suppose it makes sense that after what...nearly a 100+ years of lead acid battery technology, it would be rare for a silver bullet solution to arrive to save the day. ;-)  Thus, it does seem like there is more to learn about LiFePO4 background and implementation than I originally had considered.   Nevertheless, there seems to be enough positives about them to take a chance on swapping out the old lead acid fixtures for the newer technology.  A few things that I've (hopefully correctly) gathered from the information here and elsewhere is:

1)  Do one's homework on the supplier as well as the technology.  This includes warrantees, communication, reliability to date, and technical assistance.

2)  For our own situation, I would prefer a battery that I can easily remove in the winter months and store inside, additionally monitoring charge state to facilitate battery longevity.  This is something I can't see doing with the weight of the current lead acid batteries.

3)  The overwhelming suggestions to try to configure the battery array as one connected in parallel makes most sense using individual 36V batteries, adding to the array as power needs dictate.  Unfortunately, a LiFePO4 battery of this size in anything greater than 60 Ah still seems quite heavy....but at least there might only be one or two batteries to have to remove for the winter months.

4)  At this point I'm leaning towards trying 3 X 12V batteries (50 - 60 Ah each) connected in series, but using a 12V LiFePO4 charger to individually charge each battery....it sounds like this fosters 'equalization' of charge in each battery this way, something that might not occur if a 36V LiFePO4 charger is used across the series string.  This is a bit lean on the Ah side of things, but we tend to use the cart fairly infrequently and do not anticipate charging that often.  [Additionally I could go with 6 batteries (12V) whereby 3 are connected in series and this is connected in parallel to the additional 3 (also connected to each other in series). but such a configuration sounds a bit cumbersome.]

5)  One fly in the ointment is the desire to place a 300+ Watt solar panel atop the vehicle for supplementary solar charging  during long summer days.  Not sure how one might implement an MPPT controller for this array of LiFePO4 batteries.  How is this issue solved for home-based solar power arrays?

Anyway,.... getting closer to taking the plunge.  Hoping to get the cart back into action and don't really want to put those lead acids back in there if I can help it.

Eric H.  Thanks also for the tips on 'build yer own' batteries.  I see at DIYpow.com that they sell the individual cells for just such projects.  In my younger days with more agility and time, that may have been an attractive option, but at this point, priorities counsel otherwise.  Much thanks for these and any forthcoming responses!

Note...edited to correct the weblink to DIYpow.com....had incorrect link earlier.

Hi, I diy 3p 8s EVE LF280K battery cells. But I added Daly BMS to each pack and all things were good. Each cell was exactly 3.25 volts, making the string easy to screw together without preliminary cell equalisation. They passed all load tests and performed as advertised in every way. All accessories were purchased from this website. I hope this helps you.
https://www.neexgent.com/product/neexgent-eve-lf280k-us-stock-grade-a-3-2v-280ah-lifepo4-battery-cells.html

I love my 100 ah LiFePO4 battery for led lighting but the only drawback is it can’t be charged if the battery gets to freezing temperature.
Most of my needs are for outdoor lighting.

This is an old thread but has had some recent posts. When we built, far remote, deep forest and off grid with ZERO services, I planned solar from the beginning. 48vdc system with 8 Trojan REb blocks. I went through 2 banks in 11 years. When the 2nd bank was at end of life I went with LifeP04 blocks, actually 3ea SimpliPhi 3.8. Within the first month I was so astounded by their performance that I thought forward and if one of them failed I would not want to get by on 2 blocks. So I bought a 4th and configured them into a 2x2 bank. This upgrade is coming up on four years.

From the beginning I sought to have as close as could be a system that would be reasonably hands off in case something happened to me and the Wife had to step into operation and maintain the system. Batteries were the main demand on maintenance. 2nd would be generator operation and maintenance during low light season (PNW).  The wife has the ability to undertake specific gravity, connection service, fuel and oil, etc but she would curse my memory having to do so. Generators, sigh.

The LFP04 batteries were a major game changer. They are in the 'crouch space' instead of the outside life the Trojans. I do ZERO maintenance on the batteries except to do a balancing charge each month - or maybe every other month - or (wink). We are coming up on the 4th year of service from the LFP04 conversion. There is little no measurable difference in their performance since they were commissioned. I have done a few things to the solar over the years and nothing made the change in operation that the new batteries contributed. But the upgrade was a hit to the budget. Would I do it again? In a heartbeat.

Here are a few things:
-  No real physical maintenance;
- Safer than lead. Don't fall victim of the horror stories of exploding batteries. BS. Some cheap Chinesium batteries maybe but you get what you pay.
- Capacity: the rated amp hours ARE usable. Lead batteries with the rated storage WILL be degraded if you use them more than 50%. LFP04 could give a flip. Just don't kill them dead.
- Energy savings: We run 3 months more than less on generator power. The generator has to recharge the batteries because of lack of sunlight. The LFP04 batteries charge AND discharge with very little loss in efficiency. Over the course of the winter this amounts to many gallons of fuel not burned. Think on that.
- Oversized battery bank: We have 15 kWh of storage. We use barely half of that so we have most of a 2nd day if I bonk my head and am down. Oversizing your bank means you don't have to charge them full (a wear and tear thing) and they rarely get below 50%. LFP04 has virtually no usage memory. So not charging them full and not substantially depleting them means little to no change in performance. So you stay below a full top end voltage hit and don't go too deep. They are warranted (for what that is worth) at 80% depth of discharge for 10,000 cycles. We run around 35 to 40%.

I am new here and this is about the first time I've been able to comment on something worth writing. You can McGivor whatever but if you aren't available SOMEONE has to follow up behind you. Don't put this on other people. Build, as best you can, something that is manageable, by those behind you. If you love them you won't saddle them with a complex system that no one can operate in your absence.

BTW, I still am looking for ways to help. I just don't have much use for rocket heaters.

Jr Hill wrote:

I am new here and this is about the first time I've been able to comment on something worth writing. You can McGivor whatever but if you aren't available SOMEONE has to follow up behind you. Don't put this on other people. Build, as best you can, something that is manageable, by those behind you. If you love them you won't saddle them with a complex system that no one can operate in your absence.

This is the truth! I have iterated and refined my off grid solar system to be as simple as possible and easy for my elderly mother and lady friend to use just in case I get electrocuted at work or get hit by a truck or whatever.

There is currently no better upgrade to your offgrid solar system than moving to lithium batteries. Not all older components will be compatible. The magnum inverter is highly programmable. Some of the older c40/60 style charge controllers with potentiometers complain about battery overvoltage with lithium but can still be made to work. That said, in 2024 there is no reason to buy another lead acid bank. Ever. Flooded. AGM. Doesn’t matter. It’s dead tech. Lithium iron phosphate performance is absolutely night and day. I get up at 4:30am and turn on the toaster and water boiler at the same time and the system doesn’t blink. 100% chance if I did that with my old lead acid the voltage drop would kick my inverter off. Now I’m finding ways to use more electricity to spare propane which is my only real bill. Induction cooktop etc.  

OP you won’t regret the switch.

C Sanchez wrote:

Jr Hill wrote:

I am new here and this is about the first time I've been able to comment on something worth writing. You can McGivor whatever but if you aren't available SOMEONE has to follow up behind you. Don't put this on other people. Build, as best you can, something that is manageable, by those behind you. If you love them you won't saddle them with a complex system that no one can operate in your absence.

This is the truth! I have iterated and refined my off grid solar system to be as simple as possible and easy for my elderly mother and lady friend to use just in case I get electrocuted at work or get hit by a truck or whatever.

There is currently no better upgrade to your offgrid solar system than moving to lithium batteries. Not all older components will be compatible. The magnum inverter is highly programmable. Some of the older c40/60 style charge controllers with potentiometers complain about battery overvoltage with lithium but can still be made to work. That said, in 2024 there is no reason to buy another lead acid bank. Ever. Flooded. AGM. Doesn’t matter. It’s dead tech. Lithium iron phosphate performance is absolutely night and day. I get up at 4:30am and turn on the toaster and water boiler at the same time and the system doesn’t blink. 100% chance if I did that with my old lead acid the voltage drop would kick my inverter off. Now I’m finding ways to use more electricity to spare propane which is my only real bill. Induction cooktop etc.  

OP you won’t regret the switch.

Well... I agree wholeheartedly about lithium being a superior tech but the magnum does not support two way communication to the best of my knowledge. In my jurisdiction at least 2 way communication to the inverter and charge controller is mandatory for lithium. Not saying don't do it just that it might run into regulatory problems if inspected.
Cheers,  David

A tangentially-related question on the thread contents.

Most of what is posted above refers to LiFePO4 batteries being charged with solar.  I'm curious about an efficient wall-plug charger that might do as many different amperages, volts, and battery chemistries as possible, *within reason*.  I understand that having something to charge flashlight batteries -and- industrial forklift batteries is likely asking too much.  But I'm finding that, partially due to a learning curve, I have lead-acid batteries ranging from 12V car/tractor to golf cart 6V deep cycle (36V as a series connected pack, but has own charger...and soon upgrading to higher V) to some newer 10Ah to 100 Ah LiFePO4 batteries, each needing charging independently.  I'm thinking rather than having so many different chargers around, there may be some rather reliable unit out there, switchable (manually or automatically) between lead acid and lithum that may range from 6-12V (maybe higher?), and can be adjusted for 2 - 20 A, again possibly manually, but also via algorithm profile automatically for best life of battery.  It's not that I haven't come across some chargers that appear to do this, but if there is a brand or source of plug-in (120VAC) charger that those with years of experience have found to be robust and have useful parameters for diverse charging needs and could post those here, I would be grateful.  Thoughts welcome as well....Thanks!

John Weiland wrote:A tangentially-related question on the thread contents.

Most of what is posted above refers to LiFePO4 batteries being charged with solar.  I'm curious about an efficient wall-plug charger that might do as many different amperages, volts, and battery chemistries as possible, *within reason*.  I understand that having something to charge flashlight batteries -and- industrial forklift batteries is likely asking too much.  But I'm finding that, partially due to a learning curve, I have lead-acid batteries ranging from 12V car/tractor to golf cart 6V deep cycle (36V as a series connected pack, but has own charger...and soon upgrading to higher V) to some newer 10Ah to 100 Ah LiFePO4 batteries, each needing charging independently.  I'm thinking rather than having so many different chargers around, there may be some rather reliable unit out there, switchable (manually or automatically) between lead acid and lithium that may range from 6-12V (maybe higher?), and can be adjusted for 2 - 20 A, again possibly manually, but also via algorithm profile automatically for best life of battery.  It's not that I haven't come across some chargers that appear to do this, but if there is a brand or source of plug-in (120VAC) charger that those with years of experience have found to be robust and have useful parameters for diverse charging needs and could post those here, I would be grateful.  Thoughts welcome as well....Thanks!

This interests me a lot.  You might be best to start your own thread on that. My personal belief is you are asking too much from a single charger. The range of amperage alone would require several units let alone chemistries. I don't worry too much about it for large batteries because most of my inverters have a range of charging profiles for all the different chemistries.  Stand alone charges are usually for portable batteries. I have two in the garage for lead acid batteries for 10-100 amp hours 6 or 12 volts and an Iota charger with different plug ins for different types of batteries. The iota is a pricey option but great for charging up a clients battery bank with a small portable generator to bring them back to life.
Cheers,  David

So I just took the plunge on a moderately priced charger from a large online distributor who shall remain unnamed. ;-)   The reviews on it suggested it will do what I want it to do, even if it won't do what the manufacturers advertise it to do.  I can live with that for now.  The immediate impetus....with an addendum below....is the charging of an 100 Ah LiFePO4 (100A BMS) battery.  Without going into the rather unusual background of the issue, a reading lamp in the main living room space needs power and can't get it by other means (old house, limited outlets, unmentioned impediment to extension cord use).  I debated converting the lamp to 12V (can an E26 socket be rewired or relabeled +/- to be used as 12V?.....Do 12V bulbs even come in an E26 configuration?), but wanted to test using an inverter and battery combo and stick with the current plug, cord, and wiring to see how long it could operate under our normal useage before needing to be recharged.  The LED bulb in the socket is 12W and the inverter is 700W running.  No fan noise under these conditions.  The battery is bluetooth so one can monitor state of charge rather easily.  It was actually a bit surprising to me how quickly that little bulb drained juice out of the battery.  Unfortunately, I don't have the total number of hours to bring the battery from 100% down to 30% because of a strange occurrance....

Addendum:  I check the battery status nightly and one day after it showed (bluetooth reading from BMS) a charge level of ~50%, my wife noted to me that she had turned off the inverter due to an 'insufficient charge' error code.  This seemed odd, but sure enough when I connected the phone app, the battery was registering 0%!  As my only LiFePO4 charger at the moment is a fixed 3A charger, I began a recharge and noticed it starting to fill as expected.  The 4 individual cells were equally charging as well.  Needless to say, charging that battery with this small charger will take some time (and monitoring of the temperature of the charger!) but eventually it got back to 100%.  So I'm left confused about the precipitous charge drop from ~50% to 0%.  I will note that even though the light was not on during this time, the inverter was.....normally the inverter is turned off after the light is turned off for the night.

The battery is now charged up again to 100%....single cell voltage at 3.4 across all 4 cells.  Any thoughts on why this may have happened before I begin use again?  The new charger will arrive any day now and can do LiFePO4 charging at 2, 10, and 25A, so hoping to get faster charging out of this unit.  Also, I suspect conversion of the lamp to 12V would allow for longer operation before recharging due to eliminating inverter draw, correct? As always, thanks for insights and comments.