Mixing DiY LifePo4 Batteries with Rack Server Batteries?

[MWeiss]

I currently have 3 banks of 16S 280 Ah EVE LifePo4 batteries with three JK 48V BMS modules. They are setup in parallel on a buss bar.

I'm considering adding more battery capacity but lack space for another battery cabinet. I have an opportunity to get two 5kWh rack server batteries as part of a refund exchange for some defective solar panels. I have room for a couple of 19x18 inch rack modules.

My question is what other considerations besides matching voltage and battery chemistry are there? Did I miss anything that would make it a bad idea to parallel or add on this extra pair of batteries?

 

[Crowz]

Everything Ive read on here I'd run them if it was me.

I personally like keeping the AH close together but everything Ive read on here says its not that important.

 

[timselectric]

No problem at all.
I ran 5 diy and a server rack battery, without issue.

 

[sunsurfer]

I'm curious to hear about these defective solar panels if you don't mind sharing.

 

[Mark48vMagnum]

I assume these 2 additional batteries are an EG4 Lifepower4 or EG4-LL's. Either way check your firmware version and if its not the latest I would update them. IMHO

 

[MWeiss]

Thanks for assuring me that there is no issue. The company that is providing a partial refund/credit didn't seem to want to send server rack batteries in lieu of cash refund:


I bought some solar panels 2 years ago, 450W, 16 of them and they performed very well. So in planning to replace other old panels, I bought from the same company, a larger 550W panel, 16 of them. Installed the first 8 but their output and even VOC in direct noon sun was significantly below nameplate rating, unlike the first set of panels I bought from them. So we've been back and forth negotiating since May. I wanted the panels replaced as defective. They would not go that far, so we're setting on a partial refund or credit for two server rack batteries to make up the shortfall in energy production.

 

[MWeiss]

I assume these 2 additional batteries are an EG4 Lifepower4 or EG4-LL's. Either way check your firmware version and if its not the latest I would update them. IMHO

No, they are a different brand.

 

[sunsurfer]

I bought some solar panels 2 years ago, 450W, 16 of them and they performed very well. So in planning to replace other old panels, I bought from the same company, a larger 550W panel, 16 of them. Installed the first 8 but their output and even VOC in direct noon sun was significantly below nameplate rating, unlike the first set of panels I bought from them. So we've been back and forth negotiating since May. I wanted the panels replaced as defective. They would not go that far, so we're setting on a partial refund or credit for two server rack batteries to make up the shortfall in energy production.

Thats impressive. Squeaky wheel get the grease. We will have to mark this day down in history for your getting a performance warranty on panels.

 

[MWeiss]

I've been negotiating since May. I installed the first 8 panels, found them to be making 72% of nameplate, even less output than the 20+ year old panels these replaced, and horrid in low light (30% down in cloudy conditions over the old panels). VOC was significantly low, and measured out put of a 550W panel was about 375W.
It's as if they were aware of a problem with quality, because they were quick to offer a 20% refund at first. But I insisted I want the panels replaced with ones that meet spec. They couldn't do that, but they are considering a refund enough to buy 10kWh of rack server batteries.
I still think they're a good company, as other companies would have flipped the proverbial "bird" at the customer, rather than try to work out some mutually satisfactory compensation.