Excel 365, empty cell's

I want to add rows to an Excel Workbook, which may or may not contain empty values.
My Problem is, that the Excel Module won’t accept empty values at all.
Errormessage: * Missing value of required parameter ‘values’.

As a workarround, i enter ’ which is not shown by excel directly. But it needs to be empty.

Is there any chance to enter something like void, oder null?

I also tried, “emptystring” which also commits the error.