Scored a heap of lead acids next port of call.

[Daddy Tanuki]

I've been looking at the data sheets. They don't seem to bad they will likely be doing 25% dod.

While far from ideal I fully admit. I have the option to get more and could easy scale to 2 or 3000ah capacity.

If it dies a short painfully death I've lost nothing maybee $500 in misc items.

My inverters will be lithium ready. So then I'll likey go rack mount batts. I may go 2 x mpp solars or similar.

I'm not the first person to obtain these. But I'm the first person to obtain a full battery bank.

as long as you understand the situation, and are willing to work with them then free is good. like I said worse case you can always sell them as lead has value. One suggesiton though, buy components that can be set for any chemistry. they cost more, but are well worth it for no other reason than you can fine tune them. example cheaper mppt's and PWM SCC have presets, but cannot be fine adjusted. the upper tier equipment, MorningStar, Victron, Midnite Solar and Outback can all be dialed in with a PC to fine tune for any chemistry. the cheaper ones cannot, they are cheaper but you are stuck with their presets.

 

[Hedges]

I've been looking at the data sheets. They don't seem to bad they will likely be doing 25% dod.

Do you see any indication of cycle life?

https://www.batteriesdirect.com.au/files/products/UXH125-6FR1591247153_1.pdf

I think they will be good as backup during occasional power failures.
With PV, they can recharge and float during the day while loads are powered by PV.
Don't know how many deep cycles you would get, maybe 50 to 100?

I use my system similarly. It has SunXtender AGM batteries, rated for 650 cycles to 70% DoD, and 10 year float life.

 

[MikeInKingman]

Below is clipped from the data sheet.
As has been pointed out, these are UPS batteries.
Everyone I've seen trying to use these over the years, has ended up regretting the journey.
They have a legitimate use, this just isn't it.
Best of luck and stay safe.