Battery capacity question

Arkansasoffgrid

Was offered several batteries from a data storage UPS facility. They are sealed, 12v, and the only data that I can find is 280w/cell/1.67v/15min.
Initial current 28A max
3yrs old, never cycled, but removed from svc 3 months ago due to facility closure. What's the best way to test them, to be sure I am not just hauling off junk?

BB.

Re: Battery capacity question

Sounds something like ~140 AH per cell. (280 WH/Cell divided by 2 volts).

So--discharge them by 50% (~70 AH) at a C/8 (leisurely rate; 140 AH / 8 Hour rate or 17.5 amp rate and and them recharge them--See how they behave.

In general, batteries designed for float service may not deep cycle very well... If you only need them to cycle by 15-25% from full--Then do that instead--They will probably last longer.

Cycle them down to 20% state of charge--They may only do that 10 times before they croak (even if they are good batteries).

Difficult to tell without data sheets.

-Bill

PNjunction

Re: Battery capacity question

The closest I could guess is that these are HRL-12280W agm's.

Some of the data sheets for the CSB brand show about 400-500 cycles down to 50% DOD. It looks like they were meant for, yep, super fast discharge ups service, but I suppose if they were perfectly cared for, you *might* be doing ok - maybe if you got them at no cost. Hard to tell if you are going to pay more for recycling them yourself.

For me, they would have to be delivered to my door free of charge, wrapped with ribbon, and a guarantee of free return pickup if they didn't work out.

zoneblue

Re: Battery capacity question

Yea, theres a guy on the midnite forum, who went through several (literally) sets of such things, before relenting and buying a proper pack. Only do it want the aggravation/learning.