I use the OFf-ROAD POPUP trailer BATTERY BANK all the time for all kinds of backup things here at my house...
One year we was without House power here for a week due to a hurricane coming close by and we was the block party location every evening... Watched HDTV and cooked on the grill. Was doing the same thing of running off the batteries and recharging the next morning with the generator for three hours. The only problem I had then was finding a working gas station close by in the county. No one had emergency power haha...
Planning on building up an outside BATTERY BANK for the house now using the same idea... My low key UPS unit...
My radio room and all its electronics never goes off grid... The rest of the house we have to plug-in at different places to keep the main thing going when the need arrives...
Great time to exercise my 2KW generator running three hours each morning re-charging my battery banks...
Roy Ken