Hello, Camelracer.
We met at the Anza-Borrego FWC Rally last Fall. We chatted a bit. You had LenSun panels up top, (jealous) nice ...
From what info I have gleaned, over the last 2 years, it would not be “advisable” to mix & match LFP4 Batteries. One, or the other, likely the new one, would be parasitic over the long term. I recently had cause to want another LFP4 Battery, a smaller 50AH, to build a portable power box. I wanted Bluetooth like my StarkPower. I searched & found TorquePower. It turned out the same lead Tech, Max, in the same State, N.C., formally with SP, now works at TP. I inquired about compatibility, & was told in a pinch, I could hook up my new battery purchase, in parallel, to my existing system. BUT, Max qualified, this new Battery is a different generation & should not be used in conjunction, for the long term, as there would be issues with uneven voltage & drainage. TP link below ... Give a holler ... get some info.
With less than complete understanding, I am being overly cautious with my $$$ Batteries. I am following the company recommendations. I understand the logic in the above posts just not the future ramifications. I would caution that none of us (I think) have owned LiFePo4 for more than a few years. In other words not much historical data to pull from for reference.
https://buylithium.com
Do you have a vertical or horizontal Fridge? Well Vented? As mentioned, it should not be a hog, unless it is a huge upright.
Edited by Stokeme, 29 September 2019 - 07:57 PM.