Welcome to the Community - That is a very common approach in doing an upgrade - in the simplest steps your build your new environment with a new vCenter making sure the new ESXi hosts can see the existing data stores - once it is up and running you then one at a time add the 4.1 ESXi hosts to the new vSphere 5.5. environment vmotioning the VMs to the new ESXi 5.5 hosts -
This process is spelled in the VMware's UPgrade Guide - http://pubs.vmware.com/vsphere-55/topic/com.vmware.ICbase/PDF/vsphere-esxi-vcenter-server-55-upgrade-guide.pdf