Creating a volume with libvirt that uses full capacity of the device defined in the pool?

Is there a virsh command that, when creating a volume in a LVM based pool (or any pool) that automatically takes all available space, similar to lvcreate -l 100%FREE? If not, is there a way to take an existing logical volume in the volume group that backs a LVM based libvirt pool and make it available to the libvirt pool? As is I've found it difficult to allocate all available space when creating new volumes that take all available space, partially because the unit format between virsh pool-list --details is not compatible with the unit format required when defining the volume when using multi-terabyte disks.