Repeated measure and blocking together


I am considering using a batch for each unit of 4 runs of total 16 runs, therefor I will have a total of 4 different batches (blocks). This to account for the variations found in different batches. I want to do it as it will be expensive to use 16 different batches. I also want to repeat the measurements over two different days to increase the power. Would the days also be blocks or would they just be called repeated measurements? I also thought I would assign the batches randomly to a unit of 4 runs, or would it be best to be consistent and assign each batch to 4 specific runs for each day I will repeat the experiment?