Update on our lithium "test" bank in 07 Roadtrek 190P

[booster]

I have mentioned a couple of times that I decided to do a test installation of three SOK, 206ah, 12v, "drop in" style batteries.


Having mentioned many times in the past that I felt the whole idea of "drop in" lithium swaps was not a great idea because of the differences in care and feeding that lithium require, and I still feel that way. I have watched the lithium market for a long time for pricing, features, claims (outrageous and some believeable ), etc and a few recent things made me decide it might be a feasible for our particular system because of it's programmability.


The things that have changed in the marketplace to convince me.


* Much lower pricing on lithium

* The availability of a removable cover, serviceable, drop in battery

* Ability to monitor individual cell voltages on all cells

* Improved amp hour capacity per footprint space and volume

* Class A cells being offered

* Some changes in specifications and parameters from manufacturers but all are still contradictory and only address some of what "best practices" appear to be.

* The availability of a much better alternator remote regulator that can terminate charge based on shunt measured amps to the batteries.


We had two trips planned for this summer, our yearly spring 16 days to Custer State Park in SD, and a one month long touring type trip with 2-5 day stays along the way going to the U.P. in Michigan, western New York to visit a fellow member, and then the Skyine, Blue Ridge, Smoky parkways and our final stay in Smoky Mtn NP.

We simulated how we intended to test the lithium bank on our trip to Custer, but with our 440ah of AGM batteries. We never used shore power and had the solar shut off. This gave us a comparison of what SOC the AGMs would settle at with less than the very long charge time it takes to get to 100%. As expected, they ran in the 40-85% range on that trip except for the long ride home where they got nearly to 100%.

I put the lithium in with temporary wiring when we got home and got what I felt were safe parameters. I programmed the shore charger and solar controller for them, but we did not intend to use either unless we had to. The Ample Power remote regulator on the parallel alternators was changed to a profile that was closest to decent for lithium, on the safe side and I shut off the charging by just disconnecting them from the alternators based on an ammeter on the dash.


The batteries were not very good out of the box and required a bunch of work at install, which the next post will go over. Long story short is that if they could not have the covers removed, they would not have worked adequately, IMO.