diy solar

diy solar

Charging situation and battery soc

frankz66

New Member
Joined
Sep 6, 2022
Messages
558
Location
Aci Sant'Antonio Catania
Hello everyone, on these 2 days, there was bad weather and unfortunately I could not keep the devices in line because the panels did not produce, from 360w total only a few amps for a c100 110ampere battery. I turned everything off for 2 days, I just left the battery charged in cloudy weather. This morning I found on the eepever the battery status or the 100% soc and only 0,200 watts produced. I accessed the devices at 11.00 am, and the battery took a few amps about 5 amps because the soc remained 100% without moving for a moment. I noticed that in the afternoon the battery already at 12.00 am went floated and at 4.30 pm in boost with not even an amp. The malagrado sun panels err 1 in 20 amps !! It seems that the AGM battery has completed its charging and discharging cycle now keeping itself at 65% soc and an absorption of 1 amp !! Being a novice in the sector, I ask for clarification on the battery charging procedure, which I seem to have understood in 3 phases: 1 phase charge boost up to what the battery wants to absorb, phase 2 float or maintenance of charge, phase 3 discharge boost up to 65 %. In this last phase from what I understand, even if I can the panels and batteries, the procedure will always end in the same way or with the correct discharge of the battery at about 60%. If someone wants to explain to me or rather give me a little lesson ..... thank you



PS:

I wanted to add and emphasize that I am a PV enthusiast but with very little experience, so even if my questions for some will seem simple or obvious, I ask you to be understanding, I just want to learn! Thanks to you all.
 

Attachments

  • ee.png
    ee.png
    325.3 KB · Views: 6
The % value on the EPEVER (and all voltage-based SoC indicators) is completely worthless.

The only time it is kinda accurate is when the battery has been completely dormant for 10+ hours (no charging or discharging of any kind).

It is egregiously wrong if there is ANY charge or discharge. A fully charged battery with a heavy load can easily register < 50% on those meters.

Your battery is fully charged when it has been held at 14.4-14.8V for 2-6 hours and/or when the current has dropped to below 2A depending on manufacturer. If you're not hitting these levels, you're not getting fully charged.

If you want to know your actual state of charge, https://www.mobile-solarpower.com/battery-monitors.html - the first 3 are viable.
 
The % value on the EPEVER (and all voltage-based SoC indicators) is completely worthless.

The only time it is kinda accurate is when the battery has been completely dormant for 10+ hours (no charging or discharging of any kind).

It is egregiously wrong if there is ANY charge or discharge. A fully charged battery with a heavy load can easily register < 50% on those meters.

Your battery is fully charged when it has been held at 14.4-14.8V for 2-6 hours and/or when the current has dropped to below 2A depending on manufacturer. If you're not hitting these levels, you're not getting fully charged.

If you want to know your actual state of charge, https://www.mobile-solarpower.com/battery-monitors.html - the first 3 are viable.
Thank you for answering, but the thing I'm interested in knowing is: If I leave the battery uncharged all day until sunset without having connected anything, what soc should I see? 100% or about 70% which should be what indicates that the battery must be discharged at 30% of its power?
 
Thank you for answering, but the thing I'm interested in knowing is: If I leave the battery uncharged all day until sunset without having connected anything, what soc should I see? 100% or about 70% which should be what indicates that the battery must be discharged at 30% of its power?

Already answered:

The % value on the EPEVER (and all voltage-based SoC indicators) is completely worthless.

First, the 100% number is worthless because it's not accurate when you look at it unless you KNOW it was fully charged because you KNOW it met the fully charged criteria for your battery.

Second, the 70% number is worthless because the 100% number is worthless. If you KNOW the 100% number was after a true full charge, and you KNOW not a single milliamp of juice was pulled from the battery, then the 70% number indicates: 1) the battery is defective and can't hold a charge or, 2) the battery monitor % is worthless.

One more time... the % value is completely worthless
 
Already answered:



First, the 100% number is worthless because it's not accurate when you look at it unless you KNOW it was fully charged because you KNOW it met the fully charged criteria for your battery.

Second, the 70% number is worthless because the 100% number is worthless. If you KNOW the 100% number was after a true full charge, and you KNOW not a single milliamp of juice was pulled from the battery, then the 70% number indicates: 1) the battery is defective and can't hold a charge or, 2) the battery monitor % is worthless.

One more time... the % value is completely worthless
Many users indicate the battery charge values example in my specific case the battery should be charged at 12.80 volts And it must be discharged at a voltage of not less than 12 V Where exactly do you find these parameters that I can change where they indicate 12.80 and 12 V discharge? In addition, from the data sheet of my battery I do not see exactly the voltage value that indicates the 100% full charge example 12.60 or 12.80
 

Attachments

  • Schermata 2022-09-23 alle 18.16.05.png
    Schermata 2022-09-23 alle 18.16.05.png
    333.5 KB · Views: 7
No 12V AGM battery on the planet should be charged to only 12.8V. I'm guessing you looked at some chart that says AGM is charged to 12.8V. That's completely and totally wrong.

The 12.8V refers to RESTING voltage. In this case, if the battery has sat for 10+ hours and is reading 12.8V+, then you're fairly confident it's at 100%; however, there are variations between manufacturers and one might be fully charged at 13.0V. More confidence is had if the sit time is 24h+

The image provided shows the battery is being charged to 14.50V. This is a good starting point if you don't have manufacturer specific data.

Can you provide a link to your battery?

Please read this:

 
No 12V AGM battery on the planet should be charged to only 12.8V. I'm guessing you looked at some chart that says AGM is charged to 12.8V. That's completely and totally wrong.

The 12.8V refers to RESTING voltage. In this case, if the battery has sat for 10+ hours and is reading 12.8V+, then you're fairly confident it's at 100%; however, there are variations between manufacturers and one might be fully charged at 13.0V. More confidence is had if the sit time is 24h+

The image provided shows the battery is being charged to 14.50V. This is a good starting point if you don't have manufacturer specific data.

Can you provide a link to your battery?

Please read this:

Thank you for answering now I attach the only documentation I have of the battery but unfortunately it is in German I was able to understand something thanks to Google translator anyway this is what thanks
 

Attachments

  • manuale agm 1.pdf
    321.1 KB · Views: 5
1663952166507.png

Charge at 11-16.5A to 14.5V
Since no absorption time or termination criteria have been specified, hold for the shorter of 4 hours or until the current drops below 2A - this is a general recommendation for all lead-acid batteries.

Your EPEVER does not appear to offer temperature compensation. AGM batteries require lower charge voltage when hot and higher charge voltage when cold.

1663952434140.png

The discharge voltage is misleading. That depends on the discharge current. 12.20V roughly translates to 50% for AGM, BUT again, that's at resting voltage. A load can easily pull a battery down to below 12.20V and still be well above 50% charged. Yet another reason to get a battery monitor.
 
View attachment 113171

Charge at 11-16.5A to 14.5V
Since no absorption time or termination criteria have been specified, hold for the shorter of 4 hours or until the current drops below 2A - this is a general recommendation for all lead-acid batteries.

Your EPEVER does not appear to offer temperature compensation. AGM batteries require lower charge voltage when hot and higher charge voltage when cold.

View attachment 113174

The discharge voltage is misleading. That depends on the discharge current. 12.20V roughly translates to 50% for AGM, BUT again, that's at resting voltage. A load can easily pull a battery down to below 12.20V and still be well above 50% charged. Yet another reason to get a battery monitor.
Ok, my regulator instead provides for this compensation, I even bought the sensor, I indicated the compensation status as zero, in short, I wanted to deactivate it on purpose. As for the values you indicated to me, I saw that you brought back 13.80 by default, the dealer recommended a value of 13.62 volts at a temperature of 25 °. I also wanted to add that these regulators have a maximum of 180 minutes you can't go any further. I wanted to ask you why you varied the reconnected envelope parameter and put a lower and not higher parameter? I guess you entered as a value 13 because you increased the duration of the boost is correct?
 
Ok, my regulator instead provides for this compensation, I even bought the sensor, I indicated the compensation status as zero, in short, I wanted to deactivate it on purpose.

You have a good reason for this?

As for the values you indicated to me, I saw that you brought back 13.80 by default, the dealer recommended a value of 13.62 volts at a temperature of 25 °.

Then go with dealer recommendation.

I also wanted to add that these regulators have a maximum of 180 minutes you can't go any further

Then go with 180m If you find that you are at 2A before 180m, you can reduce 180m to whatever time it takes to get to 2A.

I wanted to ask you why you varied the reconnected envelope parameter and put a lower and not higher parameter? I guess you entered as a value 13 because you increased the duration of the boost is correct?

"reconnected envelope"?

That value specifies when it triggers a whole new charge cycle. You don't want a brief voltage dip caused by clouds to trigger another 3 hour boost charge.
 
You have a good reason for this?
Yes, because he didn't know any parameters regarding charge voltage and more. Imagine that the bench didn’t even point out to me that AGMs or Gels shouldn’t be equalized. Anyway, thank you for your instructions, I will try to practice more and more! I will try to put those values in particular the 13 v
 
You have a good reason for this?



Then go with dealer recommendation.



Then go with 180m If you find that you are at 2A before 180m, you can reduce 180m to whatever time it takes to get to 2A.



"reconnected envelope"?

That value specifies when it triggers a whole new charge cycle. You don't want a brief voltage dip caused by clouds to trigger another 3 hour boost charge.
Finally, I wanted to ask you, if you use AGM GEL or lifepo4. If you use AGMs, could you send me your values screen? Thank you
 
Yes, because he didn't know any parameters regarding charge voltage and more. Imagine that the bench didn’t even point out to me that AGMs or Gels shouldn’t be equalized. Anyway, thank you for your instructions, I will try to practice more and more! I will try to put those values in particular the 13 v

The values are giving in the data.

-.018V/cell/°C

You have 6 cells, so 6 * -0.18 = -0.108V/°C

If you screen cap the setting, I can tell you what it needs to be.

Finally, I wanted to ask you, if you use AGM GEL or lifepo4. If you use AGMs, could you send me your values screen? Thank you

I do not have your controller. I do not use lead acid anymore. I use this.
 
You have 6 cells, so 6 * -0.18 = -0.108V/°C
So now I have about 22 degrees, the parameters are fine in your opinion? The adess sensor is active . On the other right the sensor pinned sideways
 

Attachments

  • Schermata 2022-09-24 alle 07.42.03.png
    Schermata 2022-09-24 alle 07.42.03.png
    328.5 KB · Views: 9
  • Schermata 2022-09-24 alle 07.45.17.png
    Schermata 2022-09-24 alle 07.45.17.png
    614.1 KB · Views: 8
where do you enter temp comp value in the charge controller?

Voltages are fine.

Is the sensor in contact with the battery?
Thank you for answering, the sensor if you see from the photo is that small metal cylinder resting or rather glued sideways. The compensation value is where it says -3 , but from the calculation you made what value should I enter? I can only put values starting with "-" and I can't enter for example positive values for example 1 2 3 , it takes ssolo -xx . The value you calculated how should I enter it? And what number? Thanks a lot
 
Wow. It's right there. :)

I've compared your battery spec to other AGM batteries, and I'm very confused. The typical AGM battery is -0.005V/cell/°C, but your battery is over 3X that value, AND the specification is based on 20°C where most other batteries are 25°C.

I am not confident the -.018°C value is correct. Here's why:

Battery at freezing: (0°-20°C) * .018V/cell/°C * 6cell = +2.16V, 2.16V + 14.5V = 16.66V

This means that at freezing your absorption voltage should be 16.66V, which is pretty outrageous.

Recommend using the more typical -.005V/cell/°C.

6 * (-.005) = -.030V = -30mV.

Just noticed it's /2V, so 2 * -30mV = -60mV
 
Wow. It's right there. :)

I've compared your battery spec to other AGM batteries, and I'm very confused. The typical AGM battery is -0.005V/cell/°C, but your battery is over 3X that value, AND the specification is based on 20°C where most other batteries are 25°C.

I am not confident the -.018°C value is correct. Here's why:

Battery at freezing: (0°-20°C) * .018V/cell/°C * 6cell = +2.16V, 2.16V + 14.5V = 16.66V

This means that at freezing your absorption voltage should be 16.66V, which is pretty outrageous.

Recommend using the more typical -.005V/cell/°C.

6 * (-.005) = -.030V = -30mV.

Just noticed it's /2V, so 2 * -30mV = -60mV
Grazie per la tua pazienza , ma purtroppo ti seguo poco perchè la mia conoscenza è limitata . Ti chiedo per farvore di scrivere nei riquadri mancati i valori che secondo te vanno bene , con la premessa che nel valore di compensazione , come scritto in precedenza , l'epever 3210 an mi accetta solo valori interi es. -2 , -3 , -4 ecc . Il boost charging che tensione ( considerato quello che avevi letto nel manuale tecnico della mia batteria ) ??? Il float ??? Grazie ancora .
 

Attachments

  • finale.png
    finale.png
    1.1 MB · Views: 2
Back
Top