While lithium ion batteries can produce an amazing amount of current from a small package, for house use amp-hours are still amp-hours. Don't be fooled by "equivalent amp-hours" or other marketing BS. That is meaningless when used as house batteries.
In addition, the cheap stuff being sold as "drop in replacement" for lead acid isn't really. In many lithium chemistries mistreatment can be quite hazardous. The LiFePo4 chemistry most commonly used for house batteries in RV/Marine, there is less fire danger but you can still damage them easily, an expensive mistake.
For someone living full time in their RV/Boat without access to shore power, you can justify the very high cost of a properly installed system because over their life they will be cheaper per amp-hour delivered than flooded lead acid. But for weekenders and holiday trips it's pretty hard to reach the payoff until the cost comes down substantially.
