Difference between "tranche" and "batch"

I work in the data science, where we tend to use "batch" to refer to collections of data points composed as follows:

Biosamples 1-10, processed as per A, on Day 1 = batch 1
Biosamples 11-20, processed as per A, on Day 2 = batch 2
Biosamples 21-30, processed as per A, on Day 3 = batch 3

We’re now working with another institution and will be combining data between the two. The data are inherently different (DNA sequencing depth, experimental platform etc.).

Biosamples 1-10, processed as per A, at location 1
Biosamples 11-20, processed as per B, at location 2

Is "batch" still the most appropriate term? I’ve seen "tranche" used in finance but wondering if "tranche" MUST be finance.

p.s. I don’t think "treatment" is appropriate because it’s not the same samples treated in two different ways