Hi Tom,
You are correct that the battery storage model in SAM is only available as part of the detailed photovoltaic model.
However, you can "trick" SAM into modeling a battery-only system using the technique that Nick describes in the
Battery Storage webinar
(the video should start at 48:06). The technique involves setting the system losses to 100% and zeroing out all of the costs associated with the PV system on the System Costs page.
Best regards,
Paul.