RV electrical systems have always been perplexing, but lots of RV owners are skipping the hassle of conventional battery and charger upgrades by using all-in-one power banks. This is my recommendation because there is no installation necessary, just plug in the shore power cord and use Bluetti power as if it were shore power. This one also includes a DC-DC charger for alternator charging.

https://amzn.to/3LWkt9V

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