De Aqui você pode usar string replace.
@echo off
set value=c:\some\path
echo %value%
set new_value=%value:\=\%
echo %new_value%
saída
c:\some\path
c:\some\path
(sim, eu acabei de aprender esse truque também)
Esse link também tem
Align Right Align text to the right i.e. to improve readability of number columns.
Left String Extract characters from the beginning of a string.
Map and Lookup Use Key-Value pair list to lookup and translate values.
Mid String Extract a Substring by Position.
Remove Remove a substring using string substitution.
Remove both Ends Remove the first and the last character of a string.
Remove Spaces Remove all spaces in a string via substitution.
Replace Replace a substring using string substitution.
Right String Extract characters from the end of a string.
Split String Split a String, Extract Substrings by Delimiters.
String Concatenation Add one string to another string.
Trim Left Trim spaces from the beginning of a string via "FOR" command.
Trim Quotes Remove surrounding quotes via FOR command.
Trim Right Trim spaces from the end of a string via substitution.
Trim Right Trim spaces from the end of a string via "FOR" command.