Thermal energy storage material

Claim 1

A thermal energy storage device for thermally conditioning a region comprising a sealed container made from a thin wall, thermally conductive material, having a large surface-to-volume ratio and containing as a thermal energy storage material a substantially solid clathrate which has a melting point above 32° F, has a latent heat of fusion approaching that of water, does not decompose at ambient temperature and pressure and is characterized by the 0--0 distance of water in the hydrogen bonded cage being less than about 2.87 Angstroms, said clathrate being formed by combining with water a clathrate forming compound having the formula ##EQU1## where each R is selected from the group consisting of alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkenyl and aryl radicals, and combinations thereof containing 1 through 8 carbon atoms; Y is nitrogen, phosphorous, or sulfur; and X is chloride, fluoride, or bromide when R contains 1 through 8 carbon atoms, is iodide when R contains 1 through 5 carbon atoms, or is butyrate, whereby, when said thermal energy storage device is placed in heat transfer relationship with the region, said clathrate absorbs heat from the region, while changing from a solid to liquid state, when the temperature of the region is above the melting point of said clathrate, and/or said clathrate releases heat to and thereby heats the region, while changing from a liquid to solid state, when the temperature of the region is below the melting point of said clathrate.

Claim 9

A method for thermally conditioning a region comprising placing a thermal energy storage material having a predetermined melting point above 32° F in heat exchange relationship with said region so that, when the temperature of said region is above said predetermined melting point, said thermal energy storage material, while changing from a solid to a liquid state, absorbs heat from said region and/or, when the temperature of said region is below said predetermined melting point, said thermal energy storage material, while changing from a liquid to a solid state, releases heat to said region, said thermal energy storage material comprising a substantially solid clathrate which is stable at ambient temperature and pressure and is formed by combining with water a clathrate forming compound having the formula ##STR2## where each R is selected from the group consisting of alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkenyl and aryl radicals and combinations thereof, containing 1 through 8 carbon atoms; Y is nitrogen, phosphorous, or sulfur; X is chloride, fluoride, or bromide when R contains 1 through 8 carbon atoms, is iodide when R contains 1 through 5 carbon atoms or is butyrate.

Claim 10

A method for thermally conditioning a region comprising placing a thermal energy storage material having a predetermined melting point above 32° F in heat exchange relationship with said region so that, when the temperature of said region is above said predetermined melting point, said thermal energy storage material, while changing from a solid to a liquid state, absorbs heat from said region and/or, when the temperature of said region is below said predetermined melting point, said thermal energy storage material, while changing from a liquid to a solid state, releases heat to said region, said thermal energy storage material comprising a substantially solid clathrate which is stable at ambient temperature and pressure and is formed by combining with water a clathrate forming compound having the formula ##STR2## where each R is selected from the group consisting of alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkenyl and aryl radicals and combinations thereof, containing 1 through 8 carbon atoms; Y is nitrogen, phosphorous, or sulfur; X is chloride, fluoride, or bromide when R contains 1 through 8 carbon atoms, is iodide when R contains 1 through 5 carbon atoms or is butyrate.