Abstract: Novel carbonate compounds and novel carbamate compounds comprise at least one carbonate or carbamate moiety that is directly bonded only to groups selected from the group consisting of alkyl groups, cycloalkyl groups, alkenyl groups, cycloalkenyl groups, alkynyl groups, cycloalkynyl groups, and combinations thereof, the groups optionally containing one or more catenary heteroatoms. At least one of the directly-bonded groups comprises at least one sulfonyl moiety. The compounds are useful as solvents for the electrolyte salts used in electrochemical devices.