My batteries don’t last when there’s no sun I need help or recommendations

[Possibility008]

I installed a 10kva 48v solar inverter system using the following:

One hybrid inverter with 120A charge controller with 3300w panels connected to it

Another 120A charge controller with 4950w solar panels connected to it

My battery bank is made up of 12, 12v 220ah tubular batteries. 4 series to give 48v, and paralleled to feed a bus bar. My total battery bank 31,680kwh.

My problem here is my system won’t power a 1000w load even 6 hours at night.

Important details to note.
1. At commissioning, I noticed the battery charges to 59v (I usually leave my charge controllers at default settings) and I could hear the battery boiling , after that I had to set both charger controllers for floaded.

2. After 3 weeks of use, I noticed corrosion at the positive and negative terminal of 2 out of the 3 48v banks connected to the bus bar.

I would like to know I anyone has experienced this or if I’m doing anything wrong from the setup. I want opinions from other professionals

Are my batteries over charged from the system because my charging current on a normal day is approximately 30A

 

[SparkyJJO]

what chemistry is the battery?

 

[Possibility008]

Lead acid battery

 

[SparkyJJO]

Did you check your electrolyte after it boiled? You had some overflow apparently since your terminals corroded. Did you clean them up after you saw that? Are they reaching 100% charge?

 

[Possibility008]

The electrolyte level didn’t drop (it didn’t boil it was a boiling sound like bubbles) and I cleaned the terminal when it corroded. The battery reach 100% charges but suddenly discharges when there’s no sun

 

[400bird]

I usually leave my charge controllers at default settings

This seems like a major problem. You should program your charge controller and inverter with settings appropriate to you battery. The random factory defaults aren't going to be best.

Are my batteries over charged from the system because my charging current on a normal day is approximately 30A

If anything your charge current is to low, lead acid batteries have a min current they like. Overcharging is a factor of your settings in the charge controller.

Read and/or post your battery charging specifications and make those adjustments in your charge controller and inverter (after checking water levels, if the water levels are good check specific gravity)

 

[Possibility008]

All the batteries are at the same voltage when I tested to see if there’s an issue with some for the batteries.

 

[400bird]

The battery reach 100% charges but suddenly discharges when there’s no sun

What read 100% ?
Was it the charge controllers? Don't trust that reading. Specific gravity or finishing a proper charge cycle are the only way to know they are fully charged.

 

[Possibility008]

This seems like a major problem. You should program your charge controller and inverter with settings appropriate to you battery. The random factory defaults aren't going to be best.

I did change the settings to Floaded and the boiling sound stopped. I don’t know if there’s any relationship between that incidence and the battery not lasting now

 

[Possibility008]

What read 100% ?
Was it the charge controllers? Don't trust that reading. Specific gravity or finishing a proper charge cycle are the only way to know they are fully charged.

I’ll do that. I just want to be sure before contacting the manufacturer. Thank you

 

[andliu]

should use a meter and check each individual battery, is there a dud in the series....

 

[MisterSandals]

Are your 12 batteries wired in a balanced manner? Happen to have a pic?

 

[Possibility008]

should use a meter and check each individual battery, is there a dud in the series....

I did that check first. All batteries where same volts but as soon as there’s load on it the volatge drops fast. I don’t want to say the batteries are bad yet because I just purchased them and I’m finding it hard to believe all 12 batteries are bad.

 

[Possibility008]

Are your 12 batteries wired in a balanced manner? Happen to have a pic?

Each 4 battery is in series to give out 48v, and3 of them are connected to a 2 separate copper bus bar labeled on the photo. The length of the cables of each battery to the bus bar is the length

I still think I’m missing something. Because all 12 batteries can’t just be bad

 

[MisterSandals]

Are your bus bars in the electrical boxes? Can we (safely) see what is inside?

It looks like there are several (?) wires going into each breaker pole. Not a good picture it looks really suspect.

 

[Possibility008]

Are your bus bars in the electrical boxes? Can we (safely) see what is inside?

It looks like there are several (?) wires going into each breaker pole. Not a good picture it looks really suspect.

View attachment 181434

 

[Possibility008]

Are your bus bars in the electrical boxes? Can we (safely) see what is inside?

It looks like there are several (?) wires going into each breaker pole. Not a good picture it looks really suspect.

View attachment 181434

View attachment 181439

 

[schmism]

i would rewire to 3 12v in parallel and then those 3 stacks in series. That means you have only 4 locations to check for 12v instead of 12.

 

[Possibility008]

Would this improve the overall battery performance? My issue is with the battery performance

i would rewire to 3 12v in parallel and then those 3 stacks in series. That means you have only 4 locations to check for 12v instead of 12.

 

[Onehand]

Check all cells SG? I find the Hydrovolt Pro hydrometer is the best out there.