I think in my other posts I mentioned that my 3 year old SLA batteries were starting to fail. I had two separate banks. My main bank that runs my house was (16) 200ah SLA 12v batteries set up in 4 sets of 4 in series for a 48v bank. They still had lots of umph, but because there were 4 in series (for 48v in each of 4 strings in parallel) as they were discharged they didn't discharge evenly.
So my actual usable capacity was seriously diminished.
I ended up selling them to a guy across town who is going to use them in 12v banks. He should get quite a bit of use out of them that way. I thought about doing something like that with them but decided I didn't want to mess with them.
I made a good deal on some used BYD LifePo4 24v 220ah packs from Batteryhookup.com. After some mishaps with shipping companies I then had to repair 4 of them damaged in shipping. The first pic shows the shattered pallet they arrived on.
![Changing from SLA to LifePo4 batteries](https://www.anotherpower.com/board/index.php?PHPSESSID=tbqmuhk5v2s9b6tv745pd9unf1&action=dlattach;topic=1397.0;attach=8812;image)
![Changing from SLA to LifePo4 batteries](https://www.anotherpower.com/board/index.php?PHPSESSID=tbqmuhk5v2s9b6tv745pd9unf1&action=dlattach;topic=1397.0;attach=8813;image)
I ended up arc welding the terminals back in place using a 12v gel battery and a carbon rod. Kind of a pain but it worked on all but one. Batteryhookup replaced the damaged packs so by repairing the damaged units I got 4 extra packs, so a net gain.
The next challenge was to get these heavy packs (125lbs per pack) into place for use. I had to beef up the shelf where the upper 2 stacks of 2 sit. Then had to build custom ramps and rig a chainfall to get them installed.
![Changing from SLA to LifePo4 batteries](https://www.anotherpower.com/board/index.php?PHPSESSID=tbqmuhk5v2s9b6tv745pd9unf1&action=dlattach;topic=1397.0;attach=8814;image)
![Changing from SLA to LifePo4 batteries](https://www.anotherpower.com/board/index.php?PHPSESSID=tbqmuhk5v2s9b6tv745pd9unf1&action=dlattach;topic=1397.0;attach=8815;image)
That took awhile as I have no help and have to figure out how to safely do it all solo. Got them in. Didn't kill myself or drop anything so its all good.
![Changing from SLA to LifePo4 batteries](https://www.anotherpower.com/board/index.php?PHPSESSID=tbqmuhk5v2s9b6tv745pd9unf1&action=dlattach;topic=1397.0;attach=8816;image)
The second bank is 24v so 6 packs in parallel. I put them on their sides and strapped them together once in place.
![Changing from SLA to LifePo4 batteries](https://www.anotherpower.com/board/index.php?PHPSESSID=tbqmuhk5v2s9b6tv745pd9unf1&action=dlattach;topic=1397.0;attach=8817;image)
These required a different custom ramp but only had to lift one at a time instead of stacks of two.
For both banks I used flattened copper thick-walled pipe for bus bars. I had picked up a coil of used air conditioner copper at a yard sale last summer. Peel off the insulation, cut to length and flatten with a vise and mallet. Beats buying copper bar stock or using/buying welding cable.
Next post I'll talk about hookup.