Functionalized carboranyl magnesium electrolyte for magnesium battery

Abstract

An electrochemical device is provided having a functionalized carboranyl magnesium electrolyte. Specifically the disclosure relates to an electrochemical device having a magnesium anode, a cathode, a current collector made of non-noble metal, and a functionalized carboranyl magnesium electrolyte. The functionalized carboranyl electrolyte includes a carboranyl anion functionalized with at least one halide, or one alkyl, aryl, alkoxy, aryloxy groups, or their partially or completely fluorinated analogues. In contact with the electrolyte, the non-noble metal cathodic current collector has unusually high oxidative stability >3.0V vs. a magnesium reference. Processes for making the electrochemical device are additionally provided.

What is claimed is: 
     
         1 . An electrochemical device, comprising:
 an anode comprising magnesium;   a cathode; and   an electrolyte in contact with the anode and the cathode, the electrolyte comprising a functionalized carboranyl magnesium salt having a formula of:
   Mg(CB i H [(i+1)-j-k] X j R k ) 2 ,   Formula I:
 
   Mg(C 2 B (i−1 )H (i-j-k) X j R k ) 2 , or   Formula II:
 
   
       a combination of at least two of the foregoing, wherein i is an integer within a range of 5 through 11, inclusive; j is an integer within a range of 0 through i inclusive; k is an integer between 0 and i inclusive; each X, independently of each other X, is fluorine, chlorine, bromine, or iodine; and each R, independently of each other R, is an alkyl, aryl, alkoxy, aryloxy, their partially or completely fluorinated analogues, or a moiety combining the aforementioned functionalities. 
     
     
         2 . The electrochemical device as recited in  claim 1 , wherein the electrolyte comprises a functionalized carboranyl magnesium salt having a formula according to Formula I. 
     
     
         3 . The electrochemical device as recited in  claim 1 , wherein an anion of the functionalized carboranyl magnesium salt of any of formulae I-II is an icosahedral closo-carboranyl anion. 
     
     
         4 . The electrochemical device as recited in  claim 1 , wherein the functionalized carboranyl magnesium salt is obtained by contacting functionalized carboranyl silver salt with a magnesium halide. 
     
     
         5 . The electrochemical device as recited in  claim 1 , wherein the electrolyte is stable at an electrical potential greater than 3.0 V. 
     
     
         6 . The electrochemical device as recited in  claim 1 , wherein the cathode comprises an organic cathode material. 
     
     
         7 . A process for preparing an electrochemical device, comprising:
 contacting an anode and a cathode with an electrolyte comprising a functionalized carboranyl magnesium salt having a formula of:
   Mg(CB i H [(i+1)-j-k] X j R k ) 2 ,   Formula I:
 
   Mg(C 2 B (i−1) H (i-j-k) X j R k ) 2 , or   Formula II:
 
   
       a combination of at least two of the foregoing, wherein i is an integer within a range of 5 through 11, inclusive; j is an integer within a range of 0 through i inclusive; k is an integer between 0 and i inclusive; each X, independently of each other X, is fluorine, chlorine, bromine, or iodine; and each R, independently of each other R, is an alkyl, aryl, alkoxy, aryloxy, their partially or completely fluorinated analogues, or a moiety combining the aforementioned functionalities. 
     
     
         8 . The process as recited in  claim 7 , wherein the electrolyte comprises a functionalized carboranyl magnesium salt having a formula according to Formula I. 
     
     
         9 . The process as recited in  claim 7 , wherein the functionalized carboranyl magnesium salt comprises an icosahedral closo-carboranyl anion. 
     
     
         10 . The process as recited in  claim 7 , wherein the functionalized carboranyl magnesium salt is obtained by contacting functionalized carboranyl silver salt with a magnesium halide. 
     
     
         11 . The process as recited in  claim 7 , wherein the electrolyte is stable at an electrical potential greater than 3.0V.