Lithium batteries

[SR71 Jet Mech]

Switching to LFP is a personal choice. Everyone’s situation and RV’s are different.
I CHOOSE to have lots of solar, LFP batteries, new converter, also an inverter/charger etc. so I can go off grid and if at all possible….NOT use a generator.
I started with 2GC2’s, then to 4, upgrading the solar as I went until I got to 1600w of solar on 3 different strings and controllers and a 300ah LFP battery.
The LA batteries served us well for 3-4 years but, trying to shave weight, faster charging system and other thing sent ME down this path. I wasn’t looking for the “latest greatest “ or “bragging rights “, just a really good reliable system that works for ME.
There is no “cost savings “ in my system and I’ll never see any return on investment.
I actually feel some or most RVers can do fine with a good set of LA batteries (not the hybrids).
If your system works great for you, enjoy it.
Personally I don’t get all the bashing because someone uses this or that. I know I got slapped around on here back when I started my system and now pretty much keep it myself.
I also like to “tinker” and it has been a fun project to play with. Designed and built my own panel tilt up system and so on.
Enjoy glamping, that’s why you bought the RV.
If you really want to know, watch you tube vids and research. Although the information from Snoobler and Mike is accurate.
To each his own……

Scott

[JRTJH]

I'm not opposed to lithium batteries. I have them in my boat. They have extended my time on the water, made my "morning or afternoon trolling motor use" into an "all day trolling motor use" and have reduced recharging batteries for tomorrow's fishing from a "most of the night event" to a "shut down the generator before we go to bed so we can sleep tonight"... We regularly camp/fish in unimproved sites, not formal campgrounds, so there's no "rules for generator use" or "neighbors to annoy", except for the raccoons that tend to be up all night, checking out whatever might be outside, which they apparently consider to be their property. They don't mind rattling cans to wake us up, so I don't feel bad with a generator keeping them awake either...

Lithium is a benefit when used to its potential. To make it worthwhile, it has to be used to its potential. If not, then it's an extravagant upgrade with no cost benefit.

The way each individual uses his/her battery power capability will determine which system has the most "cost advantage for that user".

My only reason for commenting is to "keep the ill-advised grounded"... Lithium batteries are not "the only choice for anyone who owns an RV if they want to dry camp". Many, maybe even most RV owners would NEVER see a "return on investment" by installing a "high dollar lithium battery system" and even fewer would see any return on anything more than a "basic solar recharge system". That means something like the basic Keystone system, not the $14,000 top of the line Montana 1200i-L system.

If someone wants to spend megabucks, if they can afford it (or even if they can't) that's up to them. But it's simply not necessary to add $2-3K of solar/lithium to a entry level trailer so you can enjoy what you bought.

[SR71 Jet Mech]

Yep John we are in a 100% agreement!!

Unless you get bored like me and need a project

I don’t mind if others want or need to use the Ginny, I just prefer not to if I can help it. Still doesn’t always work out that way for me either….especially late in the year (November) or early in the year (March) I’ll need to pop one on to top off. Probably not but it makes me feel better. I have yet to run this new battery below 40% overnight….. but

Scott

[JRTJH]

Scott, where we camp/fish is so remote there's nobody around to hear our generator, so the issue is primarily "recharge the boat batteries at the dock, about 200' from the trailer. There's no way to use a solar charging system, no way to "reasonably" take the boat out of the water to park it close to the trailer and there's no "sunlight in the late evening/dark of night" anyway, so it's either stop fishing when the sun is shining or recharge at night (with a generator) while relaxing around the campfire and watching the coons raid the trash pile at the fish cleaning table..

Lithium batteries have extended our fishing and reduced the charge time to be ready for tomorrow. They are a PLUS in that application. As for the trailer, the way we use it, we can go 3 or 4 days in the early spring and 5-7 days in the summer when sunset is around 10PM and we don't need the furnace to take the chill off the trailer early in the mornings. We've simply had no interest in spending the money for lithium batteries for the trailer based on how well the GC-2's have powered our camping trips.

If the way we camp changes, I'm certainly not opposed to considering or "revisiting" the investment decision. But even then, I wouldn't rule out staying with FLA batteries unless there is enough benefit to justify the expense of changing battery technology.

Right now, the 1-2 thousand needed to upgrade to an improved capacity system is better left for some other unforseen emergency or to buy a "pretty gee-gaw for the Slingshot or a new swingset for the great grand baby.....

[CampNBrew2]

"Lifecycle costs" keep being touted in favor of Lithium. This is where I am stuck. I have seen many many lithium batteries bloated and wasted. I realize these were likely of different chemistry. Have we really seen the life cycles of these batteries? And do I really trust I wont have to spend another $800 on one in just a few years?
I would love to hear more info on this as its the only thing preventing me pulling the lithium trigger.

[snoobler]

Originally Posted by CampNBrew2

"Lifecycle costs" keep being touted in favor of Lithium. This is where I am stuck. I have seen many many lithium batteries bloated and wasted. I realize these were likely of different chemistry. Have we really seen the life cycles of these batteries? And do I really trust I wont have to spend another $800 on one in just a few years?
I would love to hear more info on this as its the only thing preventing me pulling the lithium trigger.

8.5 years:

https://www.technomadia.com/2020/06/...rs-of-lifepo4/

Can find many instances of folks on DIY solar forums. This guy claimed 10 years:

https://diysolarforum.com/threads/wh...4/#post-433830

The vast majority of problems are due to:
1) purchasing raw cells for DIY from questionable sources.
2) operating battery/cells outside specifications.

Battleborn has a 10 year warranty.
SOK has a 7 year warranty.

Risk is low at this point. But again, if you don't need the advantages of Lithium, and can't live with the limitations, they may never be worth the cost.

[mikec557]

I haven't read the two links yet, but I have to add. You also have to be careful to compare apples to apples. We're talking about ONLY "lithium iron."

We're NOT talking about "lithium ion", nor "lithium polymer", nor any other lithium. In the past I used both of these to fly radio controlled airplanes. They swell up and go bad. Any article talking about these are not relevant to "lithium IRON".

For anyone trying to decide which battery chemistry to choose: if cost savings is your primary criteria, it's probably cheaper to use lead acid until you know what kind of camping you'll do the most, how much power (amp hours) you use, and how much battery maintenance (water levels) you do or do not have to do. And frankly, you'll find out how diligent you are at NOT running them down below 50% state of charge, and how good you are at keeping them charged up so they don't sulfate.

I didn't buy lithium to "save money." I bought it because: 1) I wanted 200 usable Ah, 2) I had room for only two batteries, 3) I get faster recharge with my rooftop 320 watts of solar panels, and 4) I hate checking water levels, adding distilled water, and cleaning off the top of my batteries. I hope the batteries will last a long long time. But who knows. Only time will tell.

[snoobler]

Yep. All my references have been to "LFP." LiFeP04.

All my links have pertained to LFP.

[Kzneft]

Haha, I bet you didn't think you would have stirred a nest! haha.
I just purchased two SOK 100AH batteries, but have not installed yet. One of my reasons with going lithium is 1) I hate the acid getting all over the compartment. 2) Keeping filled with distilled water. 3) The voltage drops very fast compared to lithium, and my inverter does not like that. I will be installing these come spring, then I will report back. Good luck.

[snoobler]

Originally Posted by Kzneft

Haha, I bet you didn't think you would have stirred a nest! haha.
I just purchased two SOK 100AH batteries, but have not installed yet. One of my reasons with going lithium is 1) I hate the acid getting all over the compartment. 2) Keeping filled with distilled water. 3) The voltage drops very fast compared to lithium, and my inverter does not like that. I will be installing these come spring, then I will report back. Good luck.

While voltage drop is worse with lead acid, cabling and connection quality can make LFP look worse than lead.

[Kzneft]

Originally Posted by snoobler

While voltage drop is worse with lead acid, cabling and connection quality can make LFP look worse than lead.

And that's why I will be using 2/00 cables for my battery connections. Very pricey now though !

[xrated]

Originally Posted by Kzneft

And that's why I will be using 2/00 cables for my battery connections. Very pricey now though !

I have everything needed to build my LFP battery, but I will not be doing that until the time comes that I am ready to deploy it to it's home in the camper. The BMS has been here since early Dec, cabling, lugs, master switch, balance/charger, heated/insulated battery box with pads and a digital controller.....everything that snoobler and others have been so kind as to guide me in the right direction and some excellent advice with. Yes, this is a DIY build from a total rookie that knew absolutely zero/nada/zilch about just 4 months ago. I also made sure, as sure as one can be, to buy quality cells from a supplier that I am confident in, based on many, many feedback comments on another forum. All four of my cells arrived with zero damage and 3 of the cells read 3.298V and the fourth one read 3.288 volts. Every cell had the exact same IR (Internal resistance) of 0.21 milliohms. snoobler has provided me with a method of keeping the cells top balanced and an absolute TON of information, based on his vast experience with the LFP batteries. I have no way of knowing, just like none of us do, how long they will last....but things are definitely moving in the right direction for it to be a great build for me. Hopefully, in a few more months, I will get the build completed and deployed, just in time to bring the camper out of winter hibernation and ready to hit the road for our next adventure.

The next adventure.....a road trip to Shipshewana, IN.....JC Refrigeration and the Norcold conversion to a pair of twin 12V compressors installed. These of course will convert the original Norcold absorption/electric into a reliable refrigerator for the camper. And if all goes well, I'll have more than enough 12V power via the LFP battery to run it for many years to come.

[SR71 Jet Mech]

Originally Posted by mikec557

I haven't read the two links yet, but I have to add. You also have to be careful to compare apples to apples. We're talking about ONLY "lithium iron."

We're NOT talking about "lithium ion", nor "lithium polymer", nor any other lithium. In the past I used both of these to fly radio controlled airplanes. They swell up and go bad. Any article talking about these are not relevant to "lithium IRON".

For anyone trying to decide which battery chemistry to choose: if cost savings is your primary criteria, it's probably cheaper to use lead acid until you know what kind of camping you'll do the most, how much power (amp hours) you use, and how much battery maintenance (water levels) you do or do not have to do. And frankly, you'll find out how diligent you are at NOT running them down below 50% state of charge, and how good you are at keeping them charged up so they don't sulfate.

I didn't buy lithium to "save money." I bought it because: 1) I wanted 200 usable Ah, 2) I had room for only two batteries, 3) I get faster recharge with my rooftop 320 watts of solar panels, and 4) I hate checking water levels, adding distilled water, and cleaning off the top of my batteries. I hope the batteries will last a long long time. But who knows. Only time will tell.

Pretty much my exact reasons as well.

There is no return on investment or money savings.

And LifePo4 only…..

I had to go back and reread your initial inquiry.

(BeemerJoe) You do realize that a 100ah FLA battery only yields 50ah or 50% state of charge and LifePo4 you can yield (safely) 85% or to 15% SOC? So not really a smaller battery, actually the opposite.
Not trying to sway you….just making sure you understand.

Scott

[JRTJH]

Just to clear a misconception, (possibly one that only I have), there's some "practice recommendations" going on in this thread that are similar to using "shipping weight" and "GCWR" or "maximum trailer weight" in vehicle selection and calculating how much "work" a truck can do.

The same is happening with regard to "FLA discharge percentage" or "usable amp hours with FLA batteries".

This is from the Trojan battery site:
Shallow discharges will result in a longer battery life.
50% (or less) discharges are recommended.
80% discharge is the maximum safe discharge.
Do not fully discharge flooded batteries (80% or more). This will damage (or kill) the battery. Note the statement in red (my emphasis).... https://www.trojanbattery.com/tech-s...y-maintenance/

This is from the EV Works website (a manufacturer/distributor of lithium batteries, in their LiFePO4 Care Guide:

At the other end of the scale, over-discharging can also cause cell damage. The BMS must disconnect the load if any cells are approaching empty (less than 2.5V). Cells may suffer mild damage below 2.0V, but are usually recoverable. However, cells which get driven to negative voltages are damaged beyond recovery.

On 12v batteries the use of a low voltage cutoff takes the place of the BMS by preventing the overall battery voltage going under 11.5v no cell damage should occur.

With lithium batteries, you will get longer cell life if you avoid very deep discharges. We recommend sticking to 70-80% DoD (Depth of Discharge) maximum except in emergencies. (my emphasis) https://www.evworks.com.au/page/tech...-lithium-batt/

So, we need to remember to compare "apples to apples" not "shipping weight to truck maximum trailer weight ratings"...

[snoobler]

Originally Posted by JRTJH

The same is happening with regard to "FLA discharge percentage" or "usable amp hours with FLA batteries".

This is from the Trojan battery site:
Shallow discharges will result in a longer battery life.
50% (or less) discharges are recommended.
80% discharge is the maximum safe discharge.
Do not fully discharge flooded batteries (80% or more). This will damage (or kill) the battery. Note the statement in red (my emphasis).... https://www.trojanbattery.com/tech-s...y-maintenance/

This is from the EV Works website (a manufacturer/distributor of lithium batteries, in their LiFePO4 Care Guide:

At the other end of the scale, over-discharging can also cause cell damage. The BMS must disconnect the load if any cells are approaching empty (less than 2.5V). Cells may suffer mild damage below 2.0V, but are usually recoverable. However, cells which get driven to negative voltages are damaged beyond recovery.

On 12v batteries the use of a low voltage cutoff takes the place of the BMS by preventing the overall battery voltage going under 11.5v no cell damage should occur.

With lithium batteries, you will get longer cell life if you avoid very deep discharges. We recommend sticking to 70-80% DoD (Depth of Discharge) maximum except in emergencies. (my emphasis) https://www.evworks.com.au/page/tech...-lithium-batt/

So, we need to remember to compare "apples to apples" not "shipping weight to truck maximum trailer weight ratings"...

All my calculations compared apples to apples: 50% usable capacity for lead-acid and 80% usable capacity for LFP.

The above is based on "recommended depth of discharge (DoD)" of battery manufacturers. LFP recommend 80% and LA recommends 50% (per your own link).

One can compare both at 80% DoD, but the numbers don't improve much for LA as their cycle life is cut in half.

[JRTJH]

Originally Posted by snoobler

All my calculations compared apples to apples: 50% usable capacity for lead-acid and 80% usable capacity for LFP.

The above is based on "recommended depth of discharge (DoD)" of battery manufacturers. LFP recommend 80% and LA recommends 50% (per your own link).

One can compare both at 80% DoD, but the numbers don't improve much for LA as their cycle life is cut in half.

First, you're not the only one posting in multiple threads about the "specifications of battery discharge. So my comments weren't specifically directed to any particular post, but intended for people reading any of the posts to realize that FLA batteries and LiFePO4 battery specifications are not being measured using identical standards and at least one FLA manufacturer states that it's "safe to discharge" below the "almost always quoted 50% level"...

Recheck the link... It says "50% recommended" and in the next bullet statement, it says "80% is the maximum safe discharge".. the SAME 80% for both lithium and GC2 FLA... I discharged my last set of GC2's to 70-80% regularly. They lasted 7 years and I replaced them because of a sale too good to pass up, not because they "needed replacement"...

My intent with this was to identify that there's not as much "difference when you use the same criteria" and that much of the "benefit being posted in these threads" is more the "minimum for FLA and the maximum for lithium".. That's not "apples to apples".

As I said, I have LiFePO4 in my boat and prefer them over FLA because I can get twice the amperage rating (2 batteries) with the same weight as a single FLA battery and they recharge faster. The cost, nearly $2k was something that was hard to swallow, but there was NO WAY I could put that amount of amperage in the boat using FLA batteries without sinking it.

So, I'm not "anti- LiFePO4" in every situation, but there's a lot of "best of this/worst of that" being used to compare "mine vs yours"....

Bottom line, everyone who isn't an expert needs to weigh their individual needs and wants. There's no "always correct answer" to what is best for any specific RV owner.

ADDED: The recommendation from EV Works on discharge of their LiFePO4 battery is to not discharge below 70-80%, bringing the "gap between FLA and LiFePO4 even narrower. (50 recommended/80 safe vs 70-80 recommended)

[MotoDad293]

I have 3 Lion Energy 105Ah lithium batteries. Replaced my OEM converter with the Progressive Dynamics 80amp Lithium only converter. Use the OEM Jaboni single 165watt solar panel/30amp Controller.

Roughly $2200 invested including the additional cables and misc hardware.

I can boondock for 4 days without firing up the generator except to use microwave, air conditioner or hair straightener(daughter). I keep the reefer on 12v/propane at all times. I did rewire the OEM 2000 watt inverter to support nearly every outlet in the coach. Hence why I keep the reefer on propane setting.

During the day, the 12v and 120v is minimal with the standard coach stuff drawing power in addition to other things 120v like AppleTV, cellular router. But at night there are usually 2 TVs operating for 2-4 hours plus most of the lights on.

After 4 days, will have 50-65Ah of life in the batteries out of the 315Ah bank. The single stock solar panel, most of the time, does a good job maintaining the battery state but does not generally add charge. On super bright days in the desert (CA, NV and AZ) it will add charge, not just maintain.

With shore power, builtin generator or even a Honda EU2000, I can get all 3 batteries to a full state of charge within 4 hours.

With 12v lead or AGM batteries, they would be near dead each morning. In my previous coach, I had 2 Trojan T105 6v batteries that also would be near dead each morning. Took longer to charge and had to replace annually because how frequently we would burn up the charge cycles.

I am 14 months on these batteries and seen no performance degradation. We boondock 2-3 times a month for 3-4 days each time.

Well worth the $$ invest. Now pondering adding a second solar panel though.

[snoobler]

Originally Posted by JRTJH

First, you're not the only one posting in multiple threads about the "specifications of battery discharge. So my comments weren't specifically directed to any particular post, but intended for people reading any of the posts to realize that FLA batteries and LiFePO4 battery specifications are not being measured using identical standards and at least one FLA manufacturer states that it's "safe to discharge" below the "almost always quoted 50% level"...

Recheck the link... It says "50% recommended" and in the next bullet statement, it says "80% is the maximum safe discharge".. the SAME 80% for both lithium and GC2 FLA... I discharged my last set of GC2's to 70-80% regularly. They lasted 7 years and I replaced them because of a sale too good to pass up, not because they "needed replacement"...

My intent with this was to identify that there's not as much "difference when you use the same criteria" and that much of the "benefit being posted in these threads" is more the "minimum for FLA and the maximum for lithium".. That's not "apples to apples".

As I said, I have LiFePO4 in my boat and prefer them over FLA because I can get twice the amperage rating (2 batteries) with the same weight as a single FLA battery and they recharge faster. The cost, nearly $2k was something that was hard to swallow, but there was NO WAY I could put that amount of amperage in the boat using FLA batteries without sinking it.

So, I'm not "anti- LiFePO4" in every situation, but there's a lot of "best of this/worst of that" being used to compare "mine vs yours"....

Bottom line, everyone who isn't an expert needs to weigh their individual needs and wants. There's no "always correct answer" to what is best for any specific RV owner.

ADDED: The recommendation from EV Works on discharge of their LiFePO4 battery is to not discharge below 70-80%, bringing the "gap between FLA and LiFePO4 even narrower. (50 recommended/80 safe vs 70-80 recommended)

https://ressupply.com/documents/troj...E_Brochure.pdf

Trojan’s T-105 RE is designed for 1,600 cycles at 50% DOD, which when properly sized for the capacity of your
system, will deliver longer sustained performance and longer life than the competition.


Now you're talking to me, and you're mixing references. Did you discharge TO 70-80%, or did you discharge them 70-80%? It matters. If you only discharged them to 70-80%, then yeah, they should have lasted a long time. If you're saying you discharged them TO 20% (80% DoD), then you probably didn't do it more than a few hundred times in 7 years unless you were doing it once every 2-3 days - then you'd hit 1,000 cycle.

If you weren't doing this once every 2-3 days, then you probably didn't get 1000 cycles out of it. If you only deep cycled it an average of once a week, then you didn't even rack up 400 cycles, and they actually failed prematurely at 7 years.

How often were you checking SG and topping off? How many times and how often did you run equalization charges with a special charger capable of 15.5V (see the linked datasheet)?

"lasted 7 years" is anecdotal, and you had no idea what the actual capacity remaining was when you retired them, unless you conducted a capacity test at EOL. They could have been severely deteriorated, but didn't have any dead cells and had enough to get you by, or you may only have cycled them a few hundred times (once a week), and they just dropped below what worked for you.

It's well established that 50% is the recommended discharge depth for lead acid (see above datasheet for T-105). When you design a power system, you design for 50% DoD with lead acid. Period.

It's also well established that 80% is the recommended discharge depth of LFP. When you design a power system, you design for 80% DoD with LFP. Period.

It is also SAFE to discharge LFP to 0%. It is not recommended for the same reason 50% is recommended for LA - you want longer cycle life.

Comparing two things using criteria for which they were designed is wholly appropriate, and it is apples to apples.

I'll repeat (and add) here:

Primary advantages of Lithium Iron Phosphate (LiFePO4, LFP):

1. Weigh about 50% as much as lead acid.
2. Higher operating voltage, less internal resistance/voltage sag.
3. Have much longer cycle life.
4. Have more usable capacity, 80-90% compared to lead acid (50%).
5. Completely maintenance free compared to flooded lead acid (FLA).
6. CHEAPER when you consider the $ for the total energy delivered over the longer cycle life (lower cost of ownership).
7. FASTER charging. FLA/AGM/GEL are typically limited to 0.1-.02C where LFP can be charged at 0.5C - more efficient if charging with gen.

Disadvantages:

1. Higher acquisition cost.
2. Can't be charged below freezing, or they will be damaged.
3. Tend to be limited to 100A draw per 12V due to BMS restrictions.
4. Extended storage at 100% SoC can cause deterioration, particularly in warmer temps. Best stored at 30-70% SoC.

All of the above are facts. Not opinion.

The prior cost analysis is valid based on the component designs, but we'll re-run it for your "apples to apples" comparison (you might be disappointed in the answer):

2S2P T-105: 450Ah * 0.8 = 360Ah = 4.32kWh for $650
EG4 12.8V 400Ah * 0.8 = 320Ah = 4.10kWh for $1600

T-105, 1000 cycle life @ 80% = 4320kWh
Cost: $650/4320kWh = $0.15/kWh (was only $0.12/kWh @ 50%).

EG4, 7000 cycle life @ 80% = 28700kWh
Cost: $1600/28700kWh = $0.056/kWh

0.15/0.056 = 2.7X

Cost of ownership of T-105 is 2.7X the cost of LFP over 7000 cycles because they'll need to be purchased 7 times.

So, it's actually WORSE when you insist on using "apples to apples."

I'm not sure if you realize it, but I'm not saying Lithium is better or worse. I'm saying there are reasons to choose both.

For batteries that sit around mostly on float, or only get cycled once every week or two, there's no cost benefit to buying LFP.

Even with the above analysis showing the clearly lower cost of ownership, it may be easier for folks to just drop $650 on new T-105 every few years as long as they're willing to maintain it rather than the up-front cost of the Lithium and the potential disadvantages.

Normalizing to 12V numbers, I have about 2000Ah of FLA. I have about 400Ah of AGM. I also have about 5000Ah of Lithium of various flavors (LFP, NCM-LMO, NCA). I'm not even going to mention how much NiMH I have. I also have extensive testing capabilities and have been pushing/pulling electrons through various battery chemistries on a nearly daily basis for the last 6 years in a test environment. I'm not just another moron on a forum. I've done before and after testing of equalization to quantify capacity improvement. Some people go fishing for fun. I muck with batteries.

I routinely recommend FLA and AGM over LFP when appropriate. It may simply be because they don't want to drop the coin on the LFP. That is perfectly acceptable. In fact, I've pissed some people off pointing out that they would have been better served with AGM over their LFP in a standby system that might only get cycled a few times a year.

LFP still has a ways to go before it matches the level of "thoughtlessness" LA affords in terms of user stupidity and battery survivability. You have to know the limitations and work within them. Sure, the BMS protect them, but the apathetic user is in for a shock when the battery is suddenly reading 2.8V, won't accept charge, or the whole system is shut down.

[snoobler]

Originally Posted by MotoDad293

I have 3 Lion Energy 105Ah lithium batteries. Replaced my OEM converter with the Progressive Dynamics 80amp Lithium only converter. Use the OEM Jaboni single 165watt solar panel/30amp Controller.

Roughly $2200 invested including the additional cables and misc hardware.

I can boondock for 4 days without firing up the generator except to use microwave, air conditioner or hair straightener(daughter). I keep the reefer on 12v/propane at all times. I did rewire the OEM 2000 watt inverter to support nearly every outlet in the coach. Hence why I keep the reefer on propane setting.

During the day, the 12v and 120v is minimal with the standard coach stuff drawing power in addition to other things 120v like AppleTV, cellular router. But at night there are usually 2 TVs operating for 2-4 hours plus most of the lights on.

After 4 days, will have 50-65Ah of life in the batteries out of the 315Ah bank. The single stock solar panel, most of the time, does a good job maintaining the battery state but does not generally add charge. On super bright days in the desert (CA, NV and AZ) it will add charge, not just maintain.

With shore power, builtin generator or even a Honda EU2000, I can get all 3 batteries to a full state of charge within 4 hours.

With 12v lead or AGM batteries, they would be near dead each morning. In my previous coach, I had 2 Trojan T105 6v batteries that also would be near dead each morning. Took longer to charge and had to replace annually because how frequently we would burn up the charge cycles.

I am 14 months on these batteries and seen no performance degradation. We boondock 2-3 times a month for 3-4 days each time.

Well worth the $$ invest. Now pondering adding a second solar panel though.

What are you waiting for?

Your 30A controller could handle another with a little margin left over. If it's a PWM controller, you don't want to add more.

[Javi]

Y'all have convinced me that I never, ever want to get more than 20 feet from a 50 amp pedestal without 20,000 amp hours of super magical Lithium iron batteries and a 300 acre solar farm. ��