There seems to be several solutions offered for renaming all files in a directory from mixed or upper case to all lowercase names. Of the solutions, one of the worked without issue.

ls | while read upName; do loName=`echo "${upName}" | tr '[:upper:]' '[:lower:]'`; mv "$upName" "$loName"; done

Although this was found in an Ubuntu forum, it works flawlessly in CentOS.

Source: https://ubuntuforums.org/showthread.php?t=1336909