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What is your EG4 LiFePower4 reporting as its State of Health?

DougfromdaUP

DougfromdaUP

Solar Enthusiast
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47.1 N in Michigan
There has been discussion on other threads about the SOH reported by these batteries. I think it would be interesting to see what others are having their batteries tell them about their SOH.

I have five, putting the first three in service in June 2022 and adding the last one in November 2022. They're connected by #2 cable to a very large busbar, and are racked together in a corner of the basement, so they have all received very similar treatment.
Here is what they've reported :

​
B1 cyclesB1 SOHB2 cyclesB2 SOHB3 cyclesB3 SOHB4 cyclesB4 SOHB5 cyclesB5 SOH
12098.112210012098.110198.41100
1279812910012797.910998.2899.9
14397.714510014397.712897.92799.5
156 97.515810015797.514397.74299.5
17097.217210017197.216097.46099.0
18497.018710018697.017797.17798.7
215 96.521810021896.521296.611398.2
253 95.925510025695.925395.915797.5
291 95.329210029395.329595.220096.8
298 98.229910030195.130395.120996.6
30595.113061003079531195.021796.5
Please post how your LiFePower4s have aged.

edited to add data
 
Last edited:
I've never checked them. Been running for almost a year so, I'll give er a look soon and report back.
Is it a pain to check?
 
DougfromdaUP said:
I was hoping to see if others were getting the same kind of readings
Click to expand...
We are looking for a similar answer but using different terms, SOH and Capacity seem to be the same thing. SOH/Capacity appears to affect the SOC total by increasing it by whatever the SOH decrease is from 100%.

Does your Charge Capacity remain 100Ah for all packs as mine does?

We both have one battery pack that remains at 100 across all three (SOH, SOC, and Charge Capacity).

I have been looking for information explaining why Capacity (SOH), SOC and Charge Capacity within a battery pack drifts apart.

As you mentioned on this thread, I too had many cloudy days that caused several occasions when my packs had to sit at 20-30% before getting any charge. Does this have something to do with bottom balancing vs top balancing? I hope it isn't a case of receiving bad batteries that will have fast SOH degradation.

diysolarforum.com

LFP4: Capacity vs SOC vs Charge Capacity Drift

I have been looking for information explaining why capacity, SOC and charge capacity within a battery pack can drift apart. I have read about balancing, solar capacity vs battery capacity, and other various topics but nothing I have found discusses these aspects specifically. I have 6 LFP4...
diysolarforum.com diysolarforum.com

I have 6 EG4 LFP4 batteries, one (pack 5) stays at 100% across the board while the other packs keeping going down .01% in capacity approximately every 5 cycles. Packs 3-6 went active in November 2022; packs 1-2 in January 2023.

Capacity vs SOC vs Charge Capacity 1.jpg
 
Sundown said:
We are looking for a similar answer but using different terms, SOH and Capacity seem to be the same thing. SOH/Capacity appears to affect the SOC total by increasing it by whatever the SOH decrease is from 100%.
Click to expand...
I've been using the terminology that the BMS_test software does.

"State of Health' seems to be percentage capacity of the battery compared to when it was new, as magically calculated by the bms.

"full battery capacity" is the same number as SOH, since it's a 100 ampere hour battery. That is, SOH percentage of 100 equals SOH.

"remaining battery capacity" is SOH percent of State of Charge. That is, the actual ampere hours in your degraded cell.


To reiterate, I don't think the true status of the batteries are declining as fast as the SOH indicates.
 
I think it would be good to add to each post if you are using eg4 charging profiles or user define charging. From what I can see in my inverter when using eg4 profiles are set to Bulk 56v and float 56v. From what I can see from my batteries 56v float seems kind of high. Usually at 55v they remain at 100% SOC. Currently using 56.2 bulk adn 55v float.
 
Hope I'm not out of line interjecting something.

I'm not sure if the EG4 batteries use the same BMS as the SOK 48v server rack batteries, but if they do, the SOC, SOH and Full Capacity indicators are borderline useless. I have 4 SOKs with 8-12 cycles on them and have watched the SOH change dramatically on them, from 100% to 80% and back! Ridiculous. And, the SOC is rarely confirmed by voltage unless it's just been charged.
 
akitawpo said:
I think it would be good to add to each post if you are using eg4 charging profiles or user define charging. From what I can see in my inverter when using eg4 profiles are set to Bulk 56v and float 56v. From what I can see from my batteries 56v float seems kind of high. Usually at 55v they remain at 100% SOC. Currently using 56.2 bulk adn 55v float.
Click to expand...
Good idea!
After much research and watching the current as the batteries charge, I have set the SolArk to 55.8 bulk (which ends up being 56.1) and 54.4 float (which the SolArk interprets as 54.7)
 
DougfromdaUP said:
I don't think the true status of the batteries are declining as fast as the SOH indicates
Click to expand...
@timselectric is correct, I’ve also been told similar by Andy from off grid garage: “Unless you see a dramatic difference in SOH, there is nothing to worry about”

But I am still trying to correct the battery’s internal date and time.
 
After 19 days since installation all six Lifepower4 modules show SOH as 99.8%. During the first week of use I overcharged a bit and turned on some protective BMS features. Now bulking at 56.1V with 0 minutes soak time and floating at 54.0V with no additional over voltage alarms or change in SOH. The SOH cannot be meaningful when it changes same for all 6 modules when only hit over voltage on 4 of six modules.
 
Bumped this as I added new data, also to note that the batteries are in a very temperature stable environment, rarely more than 2 degrees away from 17° Science.
 
It's been a couple of months since I added data. Battery 2 is still reporting 100% SOH. That shows what that number is worth.

In 73 days the cycles added are 38,37,38,41, and 44.
 
Sundown said:
While we are in the EG4 BMS software, does anyone know how to correct the date and time in the EG4 LFP4?

View attachment 137199
Click to expand...
When I updated battery firmware and used the updated BMS test 2.7 the date and time were corrected on mine.
Not sure if you can use 2.7 without the battery update or not. Also I think SOH is gone on 2.7, looks like you are using BMS test 1.0
 
My soh is 95.7 after 269 cycles. It affects the capacity by the same percentage and when charged it's says 100% charged capacity (95.7AH).. why can't I hit the 100AH
 
Jamsolar876 said:
Hey bumping this post as I can't seem to get a solution
Click to expand...
Don't get too hung up on what the BMS is reporting as they're not accurate. The only way to reliably track your battery's health is to use a shunt, like the Victron Smart Shunt. Also, make sure your batteries are running the latest firmware as they did make some improvements to the current measurement in the BMS but it still doesn't completely track all the current flowing through the battery and misses anything below a half an amp.
 
Sundown said:
While we are in the EG4 BMS software, does anyone know how to correct the date and time in the EG4 LFP4?

View attachment 137199
Click to expand...
Using the BMS_Test software select the "Config" tab. Enter 888888 (six eights) in the Password box. The Config tab will populate with a number of controls.

Select the battery address of the battery you want to update by setting the "Target Adr" dropdown to the battery address to be updated.
Click the "Write system time" button to update/set the BMS system time.

Modify other data at your own risk. Modifying any settings may void any EG4 warranty.
 
"BMS" is a generic term meaning Battery Management System. This can imply various functions to protect "the battery" (a number of cells in series)

One function of BMS is measuring ampere current going through the system. Another is measuring each cell's individual voltage.

Safety disconnect can be activated by too many amperes flowing for a certain period of time, or too low/high voltage per cell over certain period of time.

"MOSFET BMS" often have a "shunt resistor" to measure amperes. However, an "external shunt" is generally different. This is another topic to discuss.

State of Charge % is estimated. Good luck, please ask questions.
 
shopman said:
Don't get too hung up on what the BMS is reporting as they're not accurate. The only way to reliably track your battery's health is to use a shunt, like the Victron Smart Shunt. Also, make sure your batteries are running the latest firmware as they did make some improvements to the current measurement in the BMS but it still doesn't completely track all the current flowing through the battery and misses anything below a half an amp.
Click to expand...
Issue I'm having is that the SOH is affecting the charge capacity..so let's say the SOH is 95% and my battery is a 100AH. I'm only able to charge to 95AH and that is recorded in BMS test as 100% SOC
 
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