I eventually went for
REM compress folders to zips
for /d %%x in ("C:\Logs\*.*") do start "C:\Program Files (x86)\7-Zip\7z.exe" /b /low /wait "C:\Program Files (x86)\7-Zip\7z.exe" a -tzip "%%x.zip" "%%x\"
REM delete the original folders used to create zips
for /d %%F in ("C:\Logs\*") do rd /s /q "%%F"