Split VHDX files into smaller files?

Hi, I have a 160 GB VHDX file that is backed up with CrashPlan.  The size of the file seems to induce performance issues when backing up, as it takes many hours for CrashPlan to read through the VHDX to determine which parts have changed.  If CP is interrupted (such as due to a higher-priority file to back up), then it appears that the backup process starts the file scan over again.

Is there a way to split a VHDX file among smaller files, similar to how VMWare can split a virtual disk into 2 GB segments?  If not, any advice for making the file more backup-friendly?

Thanks!