If your “batch” is always the same Qty, you can create it as additional UoM. Usually bulk sales offer lower price or discount for “base” price, but nothing keeps you from using the same “base” price multiplied by Qty in your “batch”.
However, you will have to modify the reports for document printing, standard does not include Qty in several UoM’s - but it is not a big “development” which you are willing to avoid