In a word, YES.
In the ASW27 that is currently Sergio's, the Strobl charge controller is on the master bus before the avionics master. runs in parallel with whichever battery is selected. We wired it that way before LiFePO4 technology. Used it later with LiFePO4s.
One sunny day at Cal City I noticed after removing the batteries that the ClearNav was still running. At that point it was in "power save" mode. As soon as I touched the stick controller, the CN drew more current which dropped the voltage and it shut down.
The Strobl charger has a lower charging voltage than LiFePO4s want, so won't actually charge to full but will maintain. Like a sustainer versus self-launcher.
Jim


On Sunday, November 29, 2015 at 4:25:06 PM UTC-8, Andy Blackburn wrote:

So could you put the solar panels in parallel with the batteries through some diodes to eliminate the sitting on the grid with the avionics off scenario? That is pretty common. Sure you'd never charge the batteries, but that's not really the purpose anyway.

9B