Whenever you start a batch render run, the outcome of each rendering is recorded. You have access to this data in the Results of a batch job.
Each run has a unique ID, a timestamp when it was started and the number of videos rendered alongside with the information about successes and failures.
To see the details of a batch run, click the the ID or click anywhere in the row of the result table. In the window that opens, a list of all renderings is displayed. It contains the following data: