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How many batteries can I add to a 6000 XP

So the long and short of it is, does it really matter at the end of the day? Or are your batteries still going to age out before they have some capacity issues?
Consider an 8 battery stack, diagonally connected. With a 400 A load the currents in the batteries would be:

#1 65
#2 52
#3 43.4
#4 39.5
#5 39.5
#6 43.4
#7 52
#8 65

Batteries #1 and #8 will reach low voltage cutoff first, at which point your string is effectively only a 6 battery string. Next batteries #2 and #7 cutoff and you have effectively only a 4 battery string. Next batteries #3 ad #6 and so forth......
Seems to be a very undesirable situation. :(
 
So, I just went down to the mechanical room and
looked at the screen on each Powerpro battery, and I'm really not happy. Battery connected to Master inverter is at 20%. Battery connected to one of the slaves is at 30%, one connected to other slave is at 42%. And the two other batteries, each connected to one of the batteries that is in turn connected to a slave inverter? One is at 22%, other is at 49%! All are connected exactly the way EG4 and Current Connected recommended. What the ___?? That's a 29-point spread!

A big question is, what happens if that battery connected to the master inverter drops down to the 2% SOC limit I have set for the batteries? There's no grid to fall back on, so will the whole system shut down, or will the other batteries continue to feed the master inverter through that battery's bus bar? Seems this is something that should have been explained a heck of a lot better than it has been, by EG4.

Also, the batteries were showing 36% on Solar Assistant, which I understand is the overall average (and Solar Assistant is just relaying the info it gets from the EG4 inverters, of course). But when I looked at each inverter separately on the EG4 app, it also says 36%. Well, we're really nowhere near 36% if one of the batteries is at 20%! So, that average reading is rather useless. We use 15-20% of capacity overnight, so I'm in the sweating bullets range for a couple of these batteries. 20% is danger zone for me based on our typical usage, while 36% doesn't phase me. So, the info from the EG4 inverters (and because of them, Solar Assistant) isn't very helpful in terms of being truly useful!

Based on all this, I certainly don't think I have 70 KWH of reserve, which is what I spent thousands of additional dollars to have. And I'm also thinking that if I had connected all five of these batteries to just a single giant busbar I would at least know that the whole system wouldn't crash if one or two batteries became depleted. Frankly, I'm pissed about this.
 
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Overnight update that I hope helps someone else as they read this in the future: We made it. The 20% SOC battery noted in the post above went down to 7%, the 22% down to 9%, while the 49% went down to 37%. Other two were also about a 12-13% point drop. EG4 reported the overall SOC at 21%, which may be an accurate average but isn't of much use if what you really care about is your lowest battery's SOC. I think i need to learn more about the "share battery" setting on the 6000XP (which has been turned on since I installed these months ago). With multiple inverters I have to wonder if it's not actually harmful in terms of useful information. I noticed in the video from @Gavin Stone that he appeared to show multiple batteries reporting individual info in the EG4 app, so I need to figure out how that was accomplished.

Anyway, we just got the "main engine" string installed a few days ago after waiting months for that, so hopefully we'll hit 100% more often and the batteries will get themselves closer together, and stay closer. And today's forecast is for glorious sun, all day, with a nice day tomorrow as well. But for those wondering about multiple batteries, and monitoring those batteries, there's more to it than you might initially think.
 
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Overnight update that I hope helps someone else as they read this in the future: We made it. The 20% SOC battery noted in the post above went down to 7%, the 22% down to 9%, while the 49% went down to 37%. Other two were also about a 12-13% point drop. EG4 reported the overall SOC at 21%, which may be an accurate average but isn't of much use if what you really care about is your lowest battery's SOC. I think i need to learn more about the "share battery" setting on the 6000XP (which has been turned on since I installed these months ago). With multiple inverters I have to wonder if it's not actually harmful in terms of useful information. I noticed in the video from @Gavin Stone that he appeared to show multiple batteries reporting individual info in the EG4 app, so I need to figure out how that was accomplished.

Anyway, we just got the "main engine" string installed a few days ago after waiting months for that, so hopefully we'll hit 100% more often and the batteries will get themselves closer together, and stay closer. And today's forecast is for glorious sun, all day, with a nice day tomorrow as well. But for those wondering about multiple batteries, and monitoring those batteries, there's more to it than you might initially think.
How do the cell voltages compare between the batteries in reference to the reported SOC?
 
Overnight update that I hope helps someone else as they read this in the future: We made it. The 20% SOC battery noted in the post above went down to 7%, the 22% down to 9%, while the 49% went down to 37%. Other two were also about a 12-13% point drop. EG4 reported the overall SOC at 21%, which may be an accurate average but isn't of much use if what you really care about is your lowest battery's SOC. I think i need to learn more about the "share battery" setting on the 6000XP (which has been turned on since I installed these months ago). With multiple inverters I have to wonder if it's not actually harmful in terms of useful information. I noticed in the video from @Gavin Stone that he appeared to show multiple batteries reporting individual info in the EG4 app, so I need to figure out how that was accomplished.

Anyway, we just got the "main engine" string installed a few days ago after waiting months for that, so hopefully we'll hit 100% more often and the batteries will get themselves closer together, and stay closer. And today's forecast is for glorious sun, all day, with a nice day tomorrow as well. But for those wondering about multiple batteries, and monitoring those batteries, there's more to it than you might initially think.
OK i understand your worries, i think .. but this is not an EG4 thing.. This is a battery current thing, and I'm not sure what you are attempting use to resolve it?

You want to see all voltages, move the comms to solar assistant and you will see each battery pack. The inverter can run of voltage just as well.

They drift as you charge, discharge daily, when you top balance they "balance" this happens on just about every battery pack ever created at every level..

Now for a solution: How does your knowledge that one is 9% and the other is 37% change anything you do? The pack as a hole does have 21% SOC.. and it would take 79% to charge it back so that is accurate.. Even a shunt would show the same.. Not sure anything we do would Help or change anything .. unless there is a way to balance them somehow..
 
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Mad: you should always have one combined battery bank and not separate batteries connected to each master/slave in a setup.
 
Mad: you should always have one combined battery bank and not separate batteries connected to each master/slave in a setup.
Well, all I can say is, Tell that to the people who sell this stuff. It's wired up exactly as it shows in their manuals, through conversations, and even confirmed via a diagram I made up and shared with EG4 and Current Connected. The batteries are most definitely in parallel, but in the end, the connection to each inverter comes from the busbar on just one battery, which is how they recommend the batteries be connected.
 
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OK i understand your worries, i think .. but this is not an EG4 thing.. This is a battery current thing, and I'm not sure what you are attempting use to resolve it?
The only things I can think of to resolve it are wait for the sun to come up (what I did) or start the generator (I was close to that, but sort of wanted to see what would happen).
You want to see all voltages, move the comms to solar assistant and you will see each battery pack. The inverter can run of voltage just as well.
I need to look into how to do that (f you can easily point me to info, I'd appreciate it). Hopefully, my SOC won't drop this low again. We just got our largest string installed a few days ago (took months) and now we're past winter solstice, so hopefully we'll be able to hit 100% more often and keep things in better balance. But frankly the more I use the EG4 monitoring site and app, the less info I feel I have. It just seems to be missing things.
They drift as you charge, discharge daily, when you top balance they "balance" this happens on just about every battery pack ever created at every level..
I knew this, but I'm understanding it better now. I'm just surprised by how fast it happened. It's not like they've gone months and months without hitting 100% (a few weeks at most). I'm also trying to figure out how and why the inverters vary so much in terms of how much power each supplies to the house's load requirements. They're all three connected in an intermediate load center, but one (the master) is contributing about 2x-3x what the least-contributing one does, and the other is in the middle of those two. I'm thinking that might be contributing significantly to the battery drain, as the lowest SOC battery is the one connected directly to the master inverter.
Now for a solution: How does your knowledge that one is 9% and the other is 37% change anything you do? The pack as a hole does have 21% SOC.. and it would take 79% to charge it back so that is accurate.. Even a shunt would show the same.. Not sure anything we do would Help or change anything .. unless there is a way to balance them somehow..
Basically, I would have started the generator soon had I known I had one battery down to ~ 20% and another at 22% (and had I realized they were drifting so far apart, I might have used the generator to have the whole bank sit at 100% for longer, the last time they reached it through PV). Also, it's that last sentence in your reply that I keep wondering about, as a way to potentially address this. As the batteries in the overall pack drift further and further apart, wouldn't it make sense to have the lowest SOC battery "take a break" for a bit, as the others discharge and catch up? Seems like a not-terrible idea that could be accomplished through either a) a simple contactor switch on each batterie's + cable that disconnects that lowest SOC battery from the overall pack for a bit, or 2) software that's looking at the SOC of each battery and doing the same, but by simply telling that battery to "take a break" and not contribute to the overall energy consumption for a bit. I'm wondering what it would take to build that. Then again, this whole thing might just go away as a problem now that we have more PV installed...
 
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How do the cell voltages compare between the batteries in reference to the reported SOC?
Looks like at their lowest point (this morning, right before the sun hit the panels) they were all within 0.1V of each other (one at 51.7V, other two at 51.8V). But the lowest SOC was on the Master inverter, which showed a battery low V of 51.8 (and I'm monitoring SOC, not V, FWIW). Also, all three inverters showed a battery voltage low alarm, which makes no sense because I have that set much lower, down in the mid-40s. No battery came even close to that according to the EG4 monitoring site, but I definitely see the warning from all three inverters, within about a minute of each other.

The other bizarre thing on the EG4 site is that on the "Monitor" tab, the only individual battery info I can see shows up only when I select the master inverter, and then I see only "Battery 4". No other batteries appear. On that, Min cell is currently at 3.338V, max is at 3.342V. And it shows a 42% SOC while I'm seeing 57% for the overall pack SOC. But I can't see any of the other batteries individually.

To make things even weirder, the battery info on the right of the screen on the Monitor tab gives me info only when the Master inverter is selected in the dropdown box, and then it shows only the info for ONE battery (280AH) and a "Total Battery" count of 1 (when I have five, for a total capacity of 1400AH). But when I look at the EG4 app on my phone (which presumably pulls data from the same source as the monitor website) it clearly shows that I have 5 batteries in parallel, with 1400 AH of battery capacity. So, yeah...... Makes no sense to me.

Overall I've been very happy with this system, but it seems like something is definitely wrong with the reporting metrics. I think I'm out of the danger zone, but frankly I'm not convinced EG4's info is accurate, at least once one gets past three batteries. And I know that I'd very much like to know the SOC of my lowest battery, not just the overall pack SOC (which I find only borderline helpful). Perhaps @EG4TechSolutionsTeam can provide more insight. If helpful, I'm happy to get on a call with them.
 
Looks like at their lowest point (this morning, right before the sun hit the panels) they were all within 0.1V of each other (one at 51.7V, other two at 51.8V). But the lowest SOC was on the Master inverter, which showed a battery low V of 51.8 (and I'm monitoring SOC, not V, FWIW). Also, all three inverters showed a battery voltage low alarm, which makes no sense because I have that set much lower, down in the mid-40s. No battery came even close to that according to the EG4 monitoring site, but I definitely see the warning from all three inverters, within about a minute of each other.

The other bizarre thing on the EG4 site is that on the "Monitor" tab, the only individual battery info I can see shows up only when I select the master inverter, and then I see only "Battery 4". No other batteries appear. On that, Min cell is currently at 3.338V, max is at 3.342V. And it shows a 42% SOC while I'm seeing 57% for the overall pack SOC. But I can't see any of the other batteries individually.

To make things even weirder, the battery info on the right of the screen on the Monitor tab gives me info only when the Master inverter is selected in the dropdown box, and then it shows only the info for ONE battery (280AH) and a "Total Battery" count of 1 (when I have five, for a total capacity of 1400AH). But when I look at the EG4 app on my phone (which presumably pulls data from the same source as the monitor website) it clearly shows that I have 5 batteries in parallel, with 1400 AH of battery capacity. So, yeah...... Makes no sense to me.

Overall I've been very happy with this system, but it seems like something is definitely wrong with the reporting metrics. I think I'm out of the danger zone, but frankly I'm not convinced EG4's info is accurate, at least once one gets past three batteries. And I know that I'd very much like to know the SOC of my lowest battery, not just the overall pack SOC (which I find only borderline helpful). Perhaps @EG4TechSolutionsTeam can provide more insight. If helpful, I'm happy to get on a call with them.
.1 volt is actually a fair spread. For instance I checked mine today via the battery front panels and found my max spread was .005v. All 48 cells were 3.2xx to 3.2xx but the max spread was 5 one thousands of a volt. All three batteries reported 71% SOC. I too are closed loop and have been since commissioning in July. I have 12.3K of PV and reach 100% SOC almost every day so they remain balanced I guess. I'll have to wait and see what happens in Jan/Feb as it's not likely the weather to be as favorable.
 
I need to look into how to do that (f you can easily point me to info, I'd appreciate it). Hopefully, my SOC won't drop this low again. We just got our largest string installed a few days ago (took months) and now we're past winter solstice, so hopefully we'll be able to hit 100% more often and keep things in better balance. But frankly the more I use the EG4 monitoring site and app, the less info I feel I have. It just seems to be missing things.
I just did it a few weeks ago to see how it all worked. So here are the steps.

1) Change the inverter to use lead acid .. charge based on battery voltage..
2) Disconnect communication from Inverter
3) Change the battery ID numbers to start with "2" and go 2,3,4,5,6,7... and not start with 1,2,3,4 like with inverter
4) Connect the CANBUS cord that came with your EG4 batteries into the USB port on SA
5) Change the battery source in SA (see image below)

1735238494991.png

Let me find that link on the SA page, it showed what to use for connect based on battery types .. I used Narada as I have the LifePower4 EG4 batteries..


Hope that helps.. If I missed anything, post and let me know, I'll try and bridge the gap.
 
The last time I connected to the EG4 website it displayed all three of my batteries independently and showed the min/max cell voltages for each separate battery. This started with the latest round of firmware. Now if they would make the local app do the same.
 
The last time I connected to the EG4 website it displayed all three of my batteries independently and showed the min/max cell voltages for each separate battery. This started with the latest round of firmware. Now if they would make the local app do the same.
I have seen some have them details, I have never seen them show up in the default app or website ..

I think the 18kPV does it ?
 
I have seen some have them details, I have never seen them show up in the default app or website ..

I think the 18kPV does it ?
My dual 6000xp's showed them. I'm not sure what exactly made it happen as I upgraded the dongles, the inverter firmware and brought all three of my batteries up to the latest available at the same time. The next time I logged into the EG4 website the three batteries were displayed independently. That however doesn't happen on the local app which is what I normally use.
 
My dual 6000xp's showed them. I'm not sure what exactly made it happen as I upgraded the dongles, the inverter firmware and brought all three of my batteries up to the latest available at the same time. The next time I logged into the EG4 website the three batteries were displayed independently. That however doesn't happen on the local app which is what I normally use.
Very odd, mine shows only this:

1735240700855.png

I have the current firmware.. And updated batteries.. But I may check it all again .. What model of batteries do you have?
 
I had to click on something...maybe the battery. My foggy memory seems to think the hot button was somewhere in the mid to upper left side.
Edit: I have 2 wall mount powerpros and one indoor wall mount.
 
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The easy solution is to run with communications (closed loop) but run via Voltage base. Then spend some time to get an idea at what SOC % is equivalent to what Voltages.

I'm not sure why anyone would want to run based on SOC %'s if inverter is capable of running based on Voltages.
The SOC % inaccuracies are a natural given due to BMS tolerances for the working range we need unless we want to spend an extra $100 to get better precision and accuracy.

As for the equivalent impedance connections for each battery, on paper it's magnified. Best practice is to try and get this close. But it's not as important since we don't have large constant loads through the whole SOC range. At lower loads, the pack will try and balance between each other.

Also, what not many account for is that as the LiFePO4 cells are discharged 20-0% true soc, it's IR rises by as much as ~30% so current naturally will adjust accordingly for parallel packs. Same when it gets to 100% SOC but not to that resistance delta. That's why we can run various size packs and they get to 0-100% at basically the smae V's.

IR will also be slightly higher for the higher loaded packs since IR increases by a few percentage points with higher C-rate if in the 15-25°C range. ie.. at 45° the c-rate ir changes very little.
 
Consider an 8 battery stack, diagonally connected. With a 400 A load the currents in the batteries would be:

#1 65
#2 52
#3 43.4
#4 39.5
#5 39.5
#6 43.4
#7 52
#8 65

Batteries #1 and #8 will reach low voltage cutoff first, at which point your string is effectively only a 6 battery string. Next batteries #2 and #7 cutoff and you have effectively only a 4 battery string. Next batteries #3 ad #6 and so forth......
Seems to be a very undesirable situation. :(
In real world usage, I have not experienced this at all. On an 8 battery bank I have, they all drop out together or within 1% or less. Now if a bank had really poor wiring, perhaps but if its wired decent, its not an issue. As the batteries with lower voltage drop below the flat part of the voltage curve, others pick up the slack. Its self balancing to a certain extent in most situations.

Now with that said, some batts will get more work over time (years) and eventually will get weaker. The less used batts will end up covering load more and more as time progresses due to internal resistance variation. If you never need to change the pack, it shouldn't matter since you will still get the same cycle/capacity life over all.
 
In real world usage, I have not experienced this at all. On an 8 battery bank I have, they all drop out together or within 1% or less. Now if a bank had really poor wiring, perhaps but if its wired decent, its not an issue. As the batteries with lower voltage drop below the flat part of the voltage curve, others pick up the slack. Its self balancing to a certain extent in most situations.

Now with that said, some batts will get more work over time (years) and eventually will get weaker. The less used batts will end up covering load more and more as time progresses due to internal resistance variation. If you never need to change the pack, it shouldn't matter since you will still get the same cycle/capacity life over all.
Are your battteries paralleled with busbar or cable? Is the load connected diagonally? Can you measure the individual battery currents under load? What are the 8 currents?
 
Are your battteries paralleled with busbar or cable? Is the load connected diagonally? Can you measure the individual battery currents under load? What are the 8 currents?
They are on some 2" aluminum round stock that is about 4 batteries wide. So basically, 2 rows of 4 batts. Multiple inverters, the main one pulls from the side but that is changing. 8 Charge controllers spread out evenly across the bars.

I am cheating a little bit, the wires are undersized on the batteries to the round bars to force more balance. Over all, current draw varies wildly every time I check with a clamp on meter. I check often. I have checked under heavy load and there is no consistent readings that would give you value.

It works very well over all for a budget setup. I also have a 24v setup of four batts with cable connect. Cross wired for load and for parallel. It also works fine. Its also about 20kwh.
 
So after messing around with the EG4 phone app for far too long and finding it worthless in terms of updating or adjusting things, I finally figured out how to use the Maintenance tab on their monitoring website to bring the inverter and dongle firmware up to date. HUGE improvement! The system now knows it has five batteries across all elements of the website, and I can see Voltage, SOC, and other battery info at the individual battery level, which makes the information far more useful. Here's a pic (you can only see 3 batteries on each row the without scrolling sideways a bit so the pic doesn't capture one).
IMG_0171.jpeg
We have decent sun again today so we should hit 100% and stay there for an hour or two, which should help with balancing. If we get over our head colds and go out in the next evening or two I may turn on the generator and let the chargeverters help as well. I didn't mean to hijack the thread but hopefully all the dialogue will help the OP and someone else in the future. The newer firmware for the 6000XP is a big help in monitoring the batteries. Thanks to all who offered up ideas and info.
 
So after messing around with the EG4 phone app for far too long and finding it worthless in terms of updating or adjusting things, I finally figured out how to use the Maintenance tab on their monitoring website to bring the inverter and dongle firmware up to date. HUGE improvement! The system now knows it has five batteries across all elements of the website, and I can see Voltage, SOC, and other battery info at the individual battery level, which makes the information far more useful. Here's a pic (you can only see 3 batteries on each row the without scrolling sideways a bit so the pic doesn't capture one).
View attachment 265787
We have decent sun again today so we should hit 100% and stay there for an hour or two, which should help with balancing. If we get over our head colds and go out in the next evening or two I may turn on the generator and let the chargeverters help as well. I didn't mean to hijack the thread but hopefully all the dialogue will help the OP and someone else in the future. The newer firmware for the 6000XP is a big help in monitoring the batteries. Thanks to all who offered up ideas and info.
What version of firmware are you using?

1735303345573.png

Mine shows up to date, but never was able to see each battery.
 
What version of firmware are you using?

View attachment 265799

Mine shows up to date, but never was able to see each battery.
Same - 190DOE. You can only see all batteries when you select the Master inverter using the monitoring website. They don't show when others are selected. They also don't show on the app (which I find is now borderline worthless). I just made an icon that takes me to the website and may end up deleting their app.
 

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