I guess cardinal numbers can be used as determiners, like this example
We looked at the job applications in two batches.
which seems more natural than another variant
We looked at the job applications in batch.
However, some situations prefer to use "batch" without determiners, like this one
However, sometimes you need to create a large number of users or import usernames from a text file. You can use newusers command, which update and create new users in batch.
Is there a rule I can follow to decide whether I should put a determiner before the countable noun "batch", to distiguish those two situations quoted above?