Server :: Split LVM2 Partition While Server Is Online?

I need to split one of my big partitions without data loss while the server is running,here is my df -h output:

Filesystem Size Used Avail Use% Mounted on
/dev/pve/root 95G 756M 89G 1% /
tmpfs 1003M 0 1003M 0% /lib/init/rw
udev 10M 2.7M 7.4M 27% /dev
tmpfs 1003M 4.0K 1003M 1% /dev/shm
/dev/mapper/pve-data 356G 52G 304G 15% /var/lib/vz
/dev/sda1 504M 32M 448M 7% /boot

I want to make a little partition from /dev/mapper/pve-data with size of 50 GB while the other files on that partition remain untouched,