Electrolyte Materials for Batteries and Methods for Use

Abstract

An electrolyte solution comprising an additive wherein the additive is not substantially consumed during charge and discharge cycles of the electrochemical cell. Additives include Lewis acids, electron-rich transition metal complexes, and electron deficient pi-conjugated systems.

1 . An electrochemical cell, comprising:
 a positive electrode comprising a first fluoride compound, the positive electrode producing a second fluoride compound upon discharge;   a negative electrode;   an electrolyte solution comprising an additive having a borate group.   
     
     
         2 - 7 . (canceled) 
     
     
         8 . The electrochemical cell of  claim 1  wherein the ratio of the amount of additive in the electrochemical cell to the amount of first fluoride compound in the electrochemical cell is less than about 0.1. 
     
     
         9 . The electrochemical cell of  claim 1  wherein the additive reduces the formation of aggregates of the second fluoride compound. 
     
     
         10 . The electrochemical cell of  claim 1  wherein the additive reversibly coordinates fluoride ions. 
     
     
         11 . The electrochemical cell of  claim 1  wherein the additive catalyzes the breakage of chemical bonds in the first fluoride compound. 
     
     
         12 . The electrochemical cell of  claim 1  wherein the additive is present in the electrolyte solution at concentrations of less than about 0.1 mol/L. 
     
     
         13 . A method of making an electrolyte solution, comprising:
 mixing a lithium salt, an organic solvent, and an additive   wherein the additive comprises a borate group.   
     
     
         14 . The method of  claim 13  wherein the additive is present in the electrolyte solution at a concentration of less than about 0.1 mol/L. 
     
     
         15 - 17 . (canceled) 
     
     
         18 . A electrolyte solution, comprising:
 a lithium salt, an organic solvent, and an additive, the additive characterized by not being substantially consumed during charge and discharge cycles of an electrochemical cell containing the electrolyte solution;   wherein the additive includes a borate group.   
     
     
         19 . The electrolyte solution of  claim 18  wherein the additive is selected from the group consisting of tri-tertbutyl borate, triethylborate, and tetramethylammonium tetrafluoroborate. 
     
     
         20 . (canceled) 
     
     
         21 . The electrochemical cell of  claim 1  wherein the additive is selected from the group consisting of tri-tertbutyl borate, triethylborate, and tetramethylammonium tetrafluoroborate. 
     
     
         22 . The method of  claim 13  wherein the additive is selected from the group consisting of tri-tertbutyl borate, triethylborate, and tetramethylammonium tetrafluoroborate. 
     
     
         23 . The electrolyte solution of  claim 18  wherein the additive comprises tri-tertbutyl borate. 
     
     
         24 . The electrolyte solution of  claim 18  wherein the additive comprises triethylborate. 
     
     
         25 . The electrolyte solution of  claim 18  wherein the additive comprises tetramethylammonium tetrafluoroborate.