EG4 Waterproof Batteries

[Trkarl]

A few weeks ago I purchased 3 EG4 waterproof 100 amp hour 48v batteries from Signature Solar. I am kind of confused about what I see on the monitoring ap with the cell voltages and state of charge. The specs downloaded from the signature solar website contradict themselves so I emailed tech support and was told to charge to 57.6 and float at 55.2 . However this is what happens when I do:
Just as the absorption cycle has been going for about 5 minutes this is what the batteries show. I have the cycle run for 15 minutes but the batteries usually go into “standby” mode at about 7 minutes with 0 amps showing. It appears to me that the state of charge indicator for each battery is highly inaccurate and two of my batteries have unbalanced cells in them. As you can see 1 of the batteries has 4 cells that are over 3.8v and the lowest cell is at 3.44v. The other unbalanced battery has a high cell of 3.787v and low cell of 3.441v.

The specs say cell overvoltage protection is at 3.9v. This seems awfully high to me from everything I have read.

I have reduced my charge voltage to 56 and still get cells in the unbalanced batteries that run above 3.65v.

Since these are sealed there is no way to take it apart to balance the unbalanced batteries. My concern is the cells with those voltages around 3.6v every charge cycle will degrade much quicker than the others. But if I don’t charge them high enough the unbalanced cells will just get more unbalanced. what are your opinions about this situation?

 

[mrall]

For all I know, my batteries are working fine but the app/firmware combo
indicate that 79% is a full charge. According to Tech Support there is no
way to reset the batteries BMS or calibrate it.

After dozens of emails and calls, Signature Solar suggested I purchase their $200 battery charger.

This did not work either.

I am considering buying a smart shunt and do a full charge and discharge
and see how close to the rated 100Ah rating. If that shows close to rated
capacity then I will just have to ignore the batteries reported SOC since
there is no way to reset, calibrate, or upgrade firmware.

I suggested to them to include a magnetic BMS reset switch in future models.

An optical serial port would be nice way to communicate with the BMS
and still maintain waterproof capabilities (like on a SmartMeter).

Victron has no trouble upgrading firmware or factory resets using Bluetooth,
why can't EG4?

I think this product is great, just a little premature to market.

Once they sealed the case without the ability to upgrade firmware,
they "sealed" the fate of these batteries.

Signature Solar's Tech Support team has been great.
I very much appreciate their professionalism.

Tier 1 Tech Support is checking to see if they will replace the batteries.

I just want something that works so I can get back to having a life...

I'll let you know what they decide...

 

[mrall]

A few weeks ago I purchased 3 EG4 waterproof 100 amp hour 48v batteries from Signature Solar. I am kind of confused about what I see on the monitoring ap with the cell voltages and state of charge. The specs downloaded from the signature solar website contradict themselves so I emailed tech support and was told to charge to 57.6 and float at 55.2 . However this is what happens when I do:
View attachment 90808View attachment 90809View attachment 90810View attachment 90811View attachment 90812View attachment 90813Just as the absorption cycle has been going for about 5 minutes this is what the batteries show. I have the cycle run for 15 minutes but the batteries usually go into “standby” mode at about 7 minutes with 0 amps showing. It appears to me that the state of charge indicator for each battery is highly inaccurate and two of my batteries have unbalanced cells in them. As you can see 1 of the batteries has 4 cells that are over 3.8v and the lowest cell is at 3.44v. The other unbalanced battery has a high cell of 3.787v and low cell of 3.441v.

The specs say cell overvoltage protection is at 3.9v. This seems awfully high to me from everything I have read.

I have reduced my charge voltage to 56 and still get cells in the unbalanced batteries that run above 3.65v.

Since these are sealed there is no way to take it apart to balance the unbalanced batteries. My concern is the cells with those voltages around 3.6v every charge cycle will degrade much quicker than the others. But if I don’t charge them high enough the unbalanced cells will just get more unbalanced. what are your opinions about this situation?

I spent a month trying to figure out the voltages to charge these batteries.

The specs printed on the battery were different than those in the manual.
One tech support guy gave me a third set of values which are different
from the values that you were given.

From Signature Solar Tech Support "I" is Alex:
Here are those programming parameters.

Charging Voltage Recommended: 58v I recommend 57.5v
DC voltage cutoff(Lowest Voltage): 43.2v I recommend 44.5v
Recommended Bulk Voltage: 57v
Recommended Float Voltage: 56.5v
Recommended Absorb Voltage: 56.5v

Coincidentally, I'm experiencing the same SOC problems...

 

[Bluedog225]

@RichardfromEG4

 

[Trkarl]

I spent a month trying to figure out the voltages to charge these batteries.

The specs printed on the battery were different than those in the manual.
One tech support guy gave me a third set of values which are different
from the values that you were given.

From Signature Solar Tech Support "I" is Alex:
Here are those programming parameters.

Coincidentally, I'm experiencing the same SOC problems...

I have settled on charging to 55.2 and floating at 54.8. This way none of the cells runs higher than 3.5 . They are all usually between 3.40 and 3.45 and in standby after 15 minutes of float which would indicate just below 100% soc. I did try to charge higher to 58 with 3 amps with my power supply to see if they would balance a bit but one went into protect mode when a cell hit 3.9 . Then the SOC reset to 100% . If that means you need to charge until it goes into protect mode in order to reset the SOC meter then I would totally disregard the SOC shown.

How far out of balance are your batteries when you get to near full? Two of mine are right around 500mV which means they were never top balanced before assembly. Anyways, unless I want to take them apart and top balance them correctly I am stuck with unbalanced batteries. Taking them apart though will void the warranty. At least with the server rack batteries you can do that without voiding the warranty.

 

[Solar Guy Richard]

Thanks for the ping. I'll be honest - one of the biggest weaknesses we have had to date is software. Our hardware is great, cells are amazing, put together practically perfectly, but our interfaces need work. We are in the process of looking at ways to improve and this is something that definitely stands out to me. I'm personally working to get our brand congruent - manuals, spec sheets, software, website....the whole deal. My best recommendation would be to 100% do the capacity test (just to rule out any capacity issues) and then from there follow the numbers Alex provided (those are the most recent from the manufacturer). Give me a few weeks but I'll have this cleaned up I'm sure before too long.

 

[MURPH-COMPLEX SYSTEMS]

I spent a month trying to figure out the voltages to charge these batteries.

The specs printed on the battery were different than those in the manual.
One tech support guy gave me a third set of values which are different
from the values that you were given.

From Signature Solar Tech Support "I" is Alex:
Here are those programming parameters.

Coincidentally, I'm experiencing the same SOC problems...

It is my understanding that lithium iron phosphate cells do not need to be put into float mode bc they are either fully charged or they are not. If that makes any sense the way I said it.. bit I'm not sure why they suggest a float voltage bc like I said I thought they are notnsupposed to "float"..is this true or an urban legend? I thought I had my mppt set right so that the float boost and eq voltage are all the same st 13.8 per 12v series for an24V system..the boost restart is set ton13.2 and they always charge ton27.7V max and never float..so that is approximately 3.45V per cell? Or is this completely th wrongnway to do this...?

 

[hwy17]

It is my understanding that lithium iron phosphate cells do not need to be put into float mode bc they are either fully charged or they are not. If that makes any sense the way I said it.. bit I'm not sure why they suggest a float voltage bc like I said I thought they are notnsupposed to "float"..is this true or an urban legend? I thought I had my mppt set right so that the float boost and eq voltage are all the same st 13.8 per 12v series for an24V system..the boost restart is set ton13.2 and they always charge ton27.7V max and never float..so that is approximately 3.45V per cell? Or is this completely th wrongnway to do this...?

If you had LFP's in like a golf cart for example, where the load is off while charging, then there would be no need to float you would just absorb until they are full and then stop.

But, with solar we usually have loads running while charging, so we need to use a float voltage to keep the charger going and the batteries topped up all day until sunset. So we do float. Float just means the voltage at which the charger will hold the bank at the end of charging.

13.5-13.8 are acceptable float voltages and it's somewhat a matter of opinion where anyone falls in that range. I float mine at the 3.4375 which would be 13.75 for 12v.

 

[MURPH-COMPLEX SYSTEMS]

So then is it okay if I'm using my batteries for solar and they stay in boost all day and never "float"..btw im using a renogy rover 60A-li charge controller? But I'm planning on upgrading to get 2 of the eg4 3kw and 4 of the eg4 48v wp batteries in conjunction with 395W hyperion bifacial does this sound like a good combination or not...also is the first scenario acceptable if I never turn my inverter off and do infact have a constant load on it?