1. Open the gift batch you're working with and go to Tools > Edit Batch Setup > Fields tab > pull over Constituent ID as a data entry field
  2. Export the batch grid to Excel
  3. Open the Excel file, delete all columns except the constituent ID column, and save the file in CSV format
  4. Create a Constituent query from a list of ID's in the excel spreadsheet using Import
  5. Open the output query created in step 4.  That query will contain all of the people from the batch.  Use the query as needed to create a mailing, export, etc.