wondering if something's wrong with my EG4 batteries

[SunbeltLocked]

I have (4) EG4 48v batteries running a VFX3648 (Outback) Inverter. I don't have a charge controller yet, so I'm running off the batteries only. I had only 2 batteries for about 2 weeks and then I recently added 2 more. Before I added the two new ones, I used a 48v charger to charge each one up until the SOC lights quit flashing. (I'm running off a generator when not using the batteries/inverter). The first thing that bothers me is the 2 older batteries are now on 1 light while the newer ones are on 2. Also, the shunt meter I have says I've consumed a total of 7kwh in the last 24 hours. My amps average about 5A. If they are 48V 100ah, shouldn't the batteries last a lot longer than that? Also, There was one time I got a red light on one of the batteries when I just had 2 working because it discharged too far. I put the charger on it and the red light quit flashing as it charged up. Is it bad to have it discharge till the red light flashes? Is it better to cycle it down to 100% DOD before charging it up? A couple of times I used the generator as AC input to the inverter to charge it back up.

 

[740GLE]

What shunt are you using?

Have all 4 packs been able charge to 100% while all connected to each other at the same time?

 

[SunbeltLocked]

Yes, I sat and watched it when all 4 were lit and the right-most one was flashing and they all came up to 100% at the same time. That told me the BMS's were working. I'll have to find the link for the shut meter I bought. Not a real expensive one.

 

[SunbeltLocked]

shunt meter

 

[740GLE]

Did the charging current stop? What was each packs voltage? Or are you just looking at blinky lights?

 

[Solar Guy Richard]

Have you individually charged them to 100%, verified voltage, then paralleled them?

 

[SunbeltLocked]

Before I added the 2 new ones, I charged each one till the charger quit and the lights went solid. They were all at around 54vdc. The 2 or 3 times I charged the 2 with the generator I watched the inverter stop charging. The inverter draws 20A from the generator.

 

[Solar Guy Richard]

Have you had a moment to connect them with a computer to verify voltage settings?

 

[SunbeltLocked]

I could never get the BMS software to work.

 

[SunbeltLocked]

Here's the dip settings I have on all 4 batteries.

 

[Shannonsman229]

Six eg4 100ah 48v. Charged each one of them individually and verified voltage is within SS recommended range before connecting together. All but one has been right on the money. I thought maybe it was the position on the bus bar so I went ahead and moved the position of the battery on my 6 space server rack twice. Still discharges faster and charges different than all of the rest.
I figured I would cycle the batteries multiple times to see if it evens out as they talk to each other. Still does the same thing. Seems like it is bringing down the rest of my batteries. It's kind of hard to see but all of my batteries have three LEDs except for the odd one that has 1 LED lit up I have hooked it up to the computer and verified voltage is lower than the rest

 

[LithiumCanuck]

Following

 

[Jack Rabbit Off Grid]

Off topic. Are the communication cables just plain old CAT5 or 6? Mine never came with them SS was out at the time. They were supposed to send them but never did. No big deal they are cheap on Amazon.

 

[Shannonsman229]

Please do not quote me but I believe they are rs485. From there to the inverter however I use CAT5 for my growatts. On my EG4 6.5 it is a custom pinned cable

 

[Kornbread]

Six eg4 100ah 48v. Charged each one of them individually and verified voltage is within SS recommended range before connecting together. All but one has been right on the money. I thought maybe it was the position on the bus bar so I went ahead and moved the position of the battery on my 6 space server rack twice. Still discharges faster and charges different than all of the rest.
I figured I would cycle the batteries multiple times to see if it evens out as they talk to each other. Still does the same thing. Seems like it is bringing down the rest of my batteries. It's kind of hard to see but all of my batteries have three LEDs except for the odd one that has 1 LED lit up I have hooked it up to the computer and verified voltage is lower than the rest

Have four of the basic eg4. Two were purchased at a later date. Have not checked the software yet, but according to the soc lights, the newer pair charge/discharge at a different rate. As you, fingers crossed they even out after enough cycles. They are all connected and communicating with the Growatt aio. These are all connected using the supplied leads onto 2"x1/4" copper buss bars that are, IIRC, 38" long. The main +/- leads to the inverter are connected at opposing corners of the buss bars, ie., + uppermost and - lowermost position on buss bar.

At what voltage, or what part of the charge cycle does the bms balance the cells?

 

[SunbeltLocked]

I purchased 2 of these about a month before the other 2 and noticed the 1st 2 seem to charge/discharge at a different rate. I recently put some buss bars on them and I'm waiting for days that are sunny so I can get up early and run the space heaters and what not to run them down and watch them recharge to see if it makes any difference. I haven't checked them using the BMS sw yet, but I'm just thinking they need to be cycled up and down a few times real good.