Here's a little more detail about the question from richinny. Many of the older "Univolt" converter-chargers need a battery in the circuit to provide stable output, so it's not a great idea to operate one of those without the battery.
With newer models (even the single-stage Parallax ones Airstream has been installing from the factory for years now) it'll work OK as long as you're careful to isolate the positive battery cable to prevent a short circuit.
Il Carriaggio — 1975 Argosy 24 | Il Progetto — 1976 Argosy 28 Center Bath | WBCCI# 15566
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