Lithium pellets coated with fluorinated oil

Abstract

Lithium fuel pellets are coated with a fluorinated oil, rather than a fluorinated polymer or telomer. The lithium pellets are coated by placing the pellets inside the lithium reaction vessel and then pouring a fluorinated oil into the reaction vessel. The reaction vessel is rotated in order to evenly coat the lithium pellets. The oil adheres to the lithium pellets and does not settle to the low point of the boiler cavity.

1 . A alkali metal-based fuel comprising:
 a plurality of alkali metal pellets; and   a fluorinated oil that adheres to the alkali metal pellets.   
   
   
       2 . The alkali metal-based fuel of  claim 1  wherein the alkali metal is lithium. 
   
   
       3 . The alkali metal-based fuel of  claim 1  wherein the fluorinated oil is a perfluoropolyether. 
   
   
       4 . The alkali metal-based fuel of  claim 1  wherein the fluorinated oil forms a coating on the surface of the lithium pellets. 
   
   
       5 . The alkali metal-based fuel of  claim 1  wherein the plurality of alkali metal pellets is a binary mixture of large and small alkali metal pellets. 
   
   
       6 . The alkali metal based fuel of  claim 5  wherein the large pellets have a diameter in excess of 8 times the diameter of the small pellets. 
   
   
       7 . The alkali metal-based fuel of  claim 5  wherein the large pellets have a volume in excess of 300 times the volume of the small pellets. 
   
   
       8 . A method of making a thermal power source comprising:
 introducing a plurality of alkali metal pellets into a reaction vessel;   introducing a fluorinated oil into the reaction vessel;   sealing the reaction vessel; and   agitating the reaction vessel to coat the alkali metal pellets with the fluorinated oil.   
   
   
       9 . The method of  claim 8  wherein the alkali metal is lithium. 
   
   
       10 . The method of  claim 8  wherein the fluorinated oil is a perfluoropolyether. 
   
   
       11 . The method of  claim 8  wherein the plurality of alkali metal pellets is a binary mixture of large and small alkali metal pellets. 
   
   
       12 . The method of  claim 11  wherein the large pellets have a diameter in excess of 8 times the diameter of the small pellets. 
   
   
       13 . The method of  claim 11  wherein the large pellets have a volume in excess of 300 times the volume of the small pellets. 
   
   
       14 . The method of  claim 8  wherein the agitation is rotation. 
   
   
       15 . A propulsion system comprising:
 a reaction vessel containing a plurality of alkali metal pellets and a fluorinated oil adhering to the plurality of alkali metal pellets,   the reaction vessel heating a fluid; and   a turbine for converting energy from the fluid into work to drive a propulsor.   
   
   
       16 . The propulsion system of  claim 15  wherein the alkali metal is lithium. 
   
   
       17 . The propulsion system of  claim 15  wherein the fluorinated oil is a perfluoropolyether. 
   
   
       18 . The propulsion system of  claim 15  wherein the fluorinated oil forms a coating on the surface of the lithium pellets. 
   
   
       19 . The propulsion system of  claim 15  wherein the plurality of alkali metal pellets is a binary mixture of large and small alkali metal pellets. 
   
   
       20 . The propulsion system of  claim 21  wherein the large pellets have a diameter in excess of 8 times the diameter of the small pellets. 
   
   
       21 . The propulsion system of  claim 21  wherein the large pellets have a volume in excess of 300 times the volume of the small pellets.