Large Server Rack Battery Bank Question

[cdnorth]

Hello, we are working on a large off grid setup. I'm fairly convinced we want to go with server rack style LiFePO4 batteries. We need something that is a UL rated assembly for permitting so EG4 and SOK both seem to meet that but capacity is where I'm getting stuck. EG4 appears to be limited to 16 batteries to maintain BMS communications and we're right about at that (planning for 18 but would like some room for expansion). Would these really not be a viable option? 16 seems like an arbitrary number and I'm not sure what triggers this or if there is something else we can do to make it work. Im not sure if SOK has a similar issue. Any suggestions?

 

[Quattrohead]

With all batteries in parallel they will eventually track each other quite close so monitoring every other one will be fine.

 

[jberger]

The limitation is the number of battery addresses available from the DIP switches on the front of the unit.

The EG4 units only have 4 switches for a total of 16.

 

[629658]

Buy bigger Ah batteries so you need less physical batteries

 

[DIYrich]

Have you looked into Redflow Battery?

 

[Nobodybusiness]

Buy bigger Ah batteries so you need less physical batteries

Wish that was the case. Almost all
Commercial batteries are 5kw.

I got some 20kw a long time ago but they weigh 400 lbs a piece.
Hard to ship and move.

 

[DIYrich]

How about dividing your off grid system into smaller micro sites. PV can serve as main grid, or AC coupled solar. Individual inverters for micro grid with their own rack battery (up to 16) per micro.

 

[629658]

Wish that was the case. Almost all
Commercial batteries are 5kw.

I got some 20kw a long time ago but they weigh 400 lbs a piece.
Hard to ship and move.

You’re looking at 100 Ah rack mounts right? Why not but 200 Ah rack mounts. I have 4 of them

 

[Nobodybusiness]

You’re looking at 100 Ah rack mounts right? Why not but 200 Ah rack mounts. I have 4 of them

These 4 are 400ah each or 20KWh.

Made up of 64 x 100ah cells.

Had these for 5 years maybe.

The top right battery went bad so replaced it with a Daly and 280ah cells couple years ago.

Each battery weighs like 370lbs.

This was all I had for a while.

Where did you get the 200ah ones?
Who’s the manufacturer?

 

[629658]

Trophy Battery. Super quick shipping outstanding support 10 yr non prorated warranty battery heaters. https://trophybattery.com/
They just rolled out a new 300Ah monster but I bought the 220 Ah’s. I have zero complaints they are working fantastic. They are heavy 250 lbs each

 

[Nobodybusiness]

Trophy Battery. Super quick shipping outstanding support 10 yr non prorated warranty battery heaters. https://trophybattery.com/
They just rolled out a new 300Ah monster but I bought the 220 Ah’s. I have zero complaints they are working fantastic. They are heavy 250 lbs each

Yup I think that’s why they downsized to the 5kw.
People can’t lift 250-300 batteries by themselves.
Had to use a cherry picker to get these in the rack.

Thanks for the info..

 

[629658]

I used a floor Jack to lift mine up