Basics of Lithium conversion... I'm lost!

[C_Schomer]

I did a search and it's mostly Greek... to me. I'd like to know the key points for, hopefully, a straight across lead/acid to lithium conversion.
My old Flow-Rite watering system just overflowed 2 cells (GRRRR) and I'm thinking this might be the time to convert.
So far I see that SiO2 is better than Li but I don't know why or what the difference is, and charging is much simpler for lithium and not so fussy.
I currently have 2 of the bigger Sams 6gc's that have dimensions and specs similar to T-105s, 2 X 120 watt panels and a Morning Star controller with remote panel/setpoint, that the PO installed.
I don't use an inverter for any 120ac loads. I'm nearly always plugged in to 120. I have no big 12vdc loads... my 5er has full LED lighting but I use a 12vdc bipap for very rare boondocking. The biggest addition might be a 12vdc fridge, someday.
Is there 6v and 12v lithium batteries? I seldom need the capacity I have now but I don't want to give it up, for the times I need the 12vdc bipap. Can I get similar capacity with lithiums and also fit the 2 x 6gc foot print? How much capacity to run a 12vdc fridge? Do I need a different solar controller or just reprogram my existing one? Thanks bunches! Craig

[Itinerant1]

There are the haves and the have nots. It's amazing that the have nots know so much more than the haves using them everday.

Most of the debates or points of contentions seem to include "best cycle life" or "long life".

What is the length of time for the "best cycle life" to be accomplished?

Using my manufacturer claimed specs for 100ah battery.
Cycle Life : >2000 (80% DOD) or (160,000ah); >3000 (70% DOD) or (210,000ah)

If you're buying them for "best cycle life" use less of the available stored energy. 60% DOD must really stretch the cycle life out.

But than I've read you can't trust the SOC monitors so are we really getting what is claimed. 😉

[3_tons]

The OP’s enquiry suggest the option of either LFP and SiO2 battery types...My self-imposed credo (in a ‘no holds’ environment...) is that I earnestly shy away from making ‘specific claims or mock-assessments’ on matters where I completely lack any first-hand experience...

So, it is in this way that I consistently choose not to offer unqualified suppositions or mock-data about the SiO2 battery option, except to suggest (my novice opinion only) that they likely beat LFP’s in cold weather (i.e. below freezing)...Where I lack information of high value (as with, SiO2), I’ll avoid speculative assessments on a battery type that in many cases may serve others quite well indeed...

3 tons, an authentic user of LFP batteries...

[3_tons]

I would only add to my previous that my non-theoretical point of disagreement here is based by actual hands-on LFP ownership, while exploiting daily harvesting and deep cycling...In the interest of complete objectivity, one need understand that the Luddite lead acid group offers only unqualified assessments...Several threads now represent this same “the sky is falling” theme...

3 tons

[3_tons]

Per PT: “ In my opinion Li are the fussy. I'm sure the lithiumites may disagree.”

Ha, it’s not that LFP’s are fussy, it’s just that ‘they’re (*) different’ (than old lead tech...), so it’s in this way that the Lithiumites happily part ways with the whip and buggy Luddites - 🙂

https://en.wikipedia.org/wiki/Luddite

* Note, For those tired of shoveling, Lithium can be uber liberating in this way - lol

3 tons, in the High Desert where ‘Lithium and Solar Harvest’ go together like Love and marriage...

[pianotuna]

thewoldwizard1,

Li have many good attributes. But they are a maze. For best life span take no lower than 40% state of charge, do not charge to more than 90%, do not float charge, store at 50% state of charge, do not charge below -4 f, have a dc to DC charger to protect the alternator, have a good battery management system, do not use above 140 f (irrc), do not draw power at greater than 0.5 C (not for all makes), have a high voltage (14.8 volts) source available to "reset" the battery management system if it "shuts down" the battery, Charge to 100% to rebalance the cells every so often, do not discharge to 0 soc, do not use temperature compensation charging, do not wire in series and initial cost is quite ridiculous unless you roll your own. I'm sure there are items I missed. I think that qualifies my statement that they are fussy.

Because each time I mention, or some one else mentions the many requirements for ideal cycle life in Li, that person is subjected to disbelief.

I should add, Li can be a great bank to own, and may offer excellent service.

[theoldwizard1]

pianotuna wrote:

In my opinion Li are the fussy. I'm sure the lithiumites may disagree.

I don't want to start an argument, I am just curious why you would say this ?

[BFL13]

Apparently all you have is some broken (badly looked after?) batts. On shore power mostly, all you need is a single 12v FLA, if that. converter can do it all. No need to jump to expensive batts to solve this.

SiO2 are not "better" than LFP, and LFP is not "better" than SiO2. AGMs are not "better" than FLA or VV either.

You just need to sort out what went wrong with the batts you have and don't do that again with new ones, if that battery bank is ok for your scenario.

[FWC]

If you use the camper a lot, and plan on keeping it for a while, then lithium may make sense as the $/A ends up being much lower over the life of the battery. But if you are mostly plugged in and only use the camper occasionally, you may never see the pay off from lithium. SiO2 is the worst of both worlds, costing much more than AGM, without the benefits of lithium.

[pianotuna]

C Schomer wrote:

So far I see that SiO2 is better than Li but I don't know why or what the difference is, and charging is much simpler for lithium and not so fussy.

In my opinion Li are the fussy. I'm sure the lithiumites may disagree.

Since you mainly plug into shore power and no inverter is in use, I would recommend any sealed battery. Your choices are Gel, AGM, Sealed lead acid, or if you have deep pockets SiO2.

[C_Schomer]

Nice... that's simple! I just looked and my Duracells are EGC2 and 75 amps/120 min. per battery. Now that I think about it... I've used "starting" AGM's in a previous truck. Isn't that the red and yellow tops? I think one mfgr went to China and there was one that stayed here. Do you know the mfgr that stayed here? I'll start shopping. Craig

[Lwiddis]

Lithium batteries when you seldom dry camp seems unnecessary and expensive to me.

[LouLawrence]

Don't change. You are welcome! If you want to upgrade an AGM will solve any watering issues. LIthium $$$$$$$$$$$$$$$$$$$$$$$$. AGM only $$$$$. Install AGM and never look at your batteries again for 5-10 years.