EMB-145 Captain reported Flight Attendant's company provided battery equipped bag was refused in aircraft cargo. Captain elected to carry the bag in the passenger cabin.

Narrative

A new Company Flight Attendant showed up at our aircraft 10 minutes before scheduled departure. She had a roller board bag that had a charging port. She was new; and said that the bag had been provided to her during training. She thought the bag had a battery in it...and ramp personnel refused to load the bag based on thinking it had a battery inside. The Flight Attendant did not know where the battery was; or how to disconnect it. In coordination with the Flight Attendant; based on our having 20 open seats... I had my Flight Attendant load the bag in an unoccupied seat. After the fact...I realized that I had not accounted for this bag in the weight and balance. I am not aware of and was unable to find any guidance regarding smart bags in the manuals; or any read files. Based on a lack of guidance for this exact situation (or at least our inability to find it); both myself and my crew felt the actions we took were appropriate...blocked out 1 minute early. Notified Chief Pilot that evening. Tried to complete report multiple times via EFB APP on Dates in coordination with Safety (unsuccessful). Completed report via home computer after trip completion.Provide guidance for crew smart bag acceptance in coordination with Company software. Or - if it already exist - make it more easily findable.