A method for producing water resistant cathodes is discussed. The method uses mixing cathode powder with solid carbon dioxide to create a mixture and heating the mixture to a temperature. The heating occurs for a time sufficient to cause lithium carbonate coatings to form on the powder. A method for coating lithium-containing cathode surfaces is also discussed. This method uses simultaneously sublimating solid CO2 and condensing atmospheric water vapor onto surfaces. Afterwards allowing the lithium to react with the sublimated CO2 for a time sufficient to create a lithium carbonate film on the surface.