@DaveB275, shame the old forum is dead and buried as there were many threads with so much info on such things. There were some die hard FLA fans with decades of experience with them who were suspicious or dismissive of lithium technology, especially 5 or more years ago. But I think the tide is or has changed somewhat. Especially with the evidence now from the use of them in electric cars.
I am one of the few who have had both types of technology and for me there is no contest.
I am ongrid, but did use a second offgrid system with FLA (forklift cells) for 6 years, then I integrated some growatt lithium cells to work in parallel with the lead acid. Long story but in the end it became evident that lithium was just so much better in so many ways (apart from cost). More efficient, longer life, no noxious explosive gasses, no need to top up with water, can leave for months at any SOC, accepts massive amounts of amps practically to full, no need for long absorption charge or any need for EQ charging.
I have roughly three 20kWh battery banks in parallel. Two are re-used growatt lithium which I re-engineered and cost similar to FLA but has been a lot of work to achieve my final working configuration. A summary of the work can be found here,
viewtopic.php?f=15&t=67
But the other bank is 8 x 2.4kWh Pylontech batteries.
They have been in use for about 4.5 years, not much to say about them other than they just work without any maintenance and are still as good as new.
If you want to go down the lithium path, you have two choices,
1) Build up your own pack with new cells, the price has now dropped to the point of being able to buy new cells at roughly £150 per kWh, but extra costs for cell balancers, etc so you will end up with circa £200 per kWh.
2) Buy something like Pylontechs for about £250 per kWh, but everything works out of the box with a 10 year warranty and being modular, if you have a failure, you just swap the failed unit out.
So, unless you like playing and tinkering with stuff, the Pylontech batteries are a no brainer. The only limitation is the 25mm cable size so is limited to about 100 Amps, unless you parallel up several banks like I do and run a larger cable to the inverter.
