If you really want to do it without using any 3-rd party compress utility, with just the batch, you can use Windows Script Host (WSH):
http://en.wikipedia.org/wiki/Windows_Script_Host[
^].
You can find a good number of code samples, this is just one of them:
http://stackoverflow.com/questions/11100696/how-to-compress-in-a-batch-file[
^].
The sample of batch file for this script is just one line (in case you did not recognize it):
CScript zip.vbs C:\test3 C:\someArchive.zip
You can also easily use WSH through PowerShell, without using VBScript or JavaScript:
http://en.wikipedia.org/wiki/Powershell[
^].
If you are interested how to do it with PowerShell, I'll need some time to find a references, so please ask about it.
—SA