Inverter and battery sizing to power my camper microwave

I don’t have BB myself, but the bargain-bin batteries dare not match their 10 year warranty (who can tell what grade or composition their cells are??), or tech service, and cylindrical cells stay cooler (due to assembly air gaps), thus no outward swelling of battery case…Quite naturally this all comes at a premium, but it’s nice to have the option - Just saying

3 tons