Battery Question

[Ronaldrwl]

Are these about the same Ah?

8x50Ah 12v = 1x100Ah 48v rack

 

[Hedges]

They are about the same Wh.
They would be the same Ah if your 8x batteries are wired 4s2p

 

[Hedges]

Just make sure BMS in 12V battery supports being wired four in series. That subjects components to higher voltage than in a 12V configuration.

Also, each 12V battery would have its cells balanced by bleeding off current from the ones that get to higher voltage. But, the 12V battery won't get balanced in relation to the others connected in series.

I think some vendors sell matched 12V batteries if you plan to use them this way. Don't know the details, but might keep them from drifting apart so fast.

 

[Ronaldrwl]

The battery racks seem the way to go and cheaper.

 

[Hedges]

Yes.
Just check up on people's experience with whichever brand server rack battery.
Some models, with some inverters, people here had trouble due to inrush.
You'll want a precharge resistor setup. (but some rack models had one built in and it caused problems.)