I guess he is referring to bin sectioning, e.g. one bin can have 3 pallets, one left one in the middle one right and the aim is to block just one section. Maybe because there is something stored which does not have a material number in SAP.
No I have not any solution for this case, the the lowest level locks are either the entire bin or just a quant.
As a workaround you could create a dummy material (material type UNBW), create some inventory and store a quant in that bin section.