LITHIUM SALTS OF CYANO-SUBSTITUTED IMIDAZOLE FOR LITHIUM ION BATTERIES
Here are described compounds for use as electrode additives or as salts in electrolyte compositions, and their methods of preparation. Also described are electrochemical cells comprising the compounds as electrode additives or as salts in electrolyte compositions.
1 . A compound as defined in any one of Formulae II to V:
wherein,
R 1 and R 2 are independently selected from H, F, CN, NO 2 , and optionally substituted alkyl;
R 5 is selected from optionally substituted C 1-6 alkyl and optionally substituted C 6 aryl;
R 6 is selected from optionally substituted C 1-6 alkyl and optionally substituted C 6 aryl;
R 7 is selected from a fluorine atom and optionally substituted C 1-6 alkyl;
R 8 and R 9 are each independently F, CN or optionally substituted C 1-6 alkyl when X 1 is a carbon atom in Formula IV or V; or
R 8 is absent and R 9 is an optionally substituted SO 2 Alkyl or optionally substituted C 1-6 alkyl when X 1 is a nitrogen atom in Formula IV or V; or
R 8 and R 9 are absent and X 1 is an oxygen atom in Formula V;
L 1 is a covalent bond, or a linker selected from optionally substituted C 1-6 alkyl and optionally substituted C 6 aryl;
m is an integer selected from 0 or 1; and
(M n+ ) 1/n is a metal cation, wherein M is an alkali metal or alkaline earth metal and n is 1 or 2;
or a tautomer thereof.
2 . The compound of claim 1 , wherein at least one of R 1 and R 2 is CN.
3 . The compound of claim 2 , wherein both of R 1 and R 2 are CN.
4 . The compound of claim 1 , wherein R 5 is an unsubstituted C 1-6 alkyl group or a fluorinated C 1-6 alkyl group.
5 . The compound of claim 1 , wherein R 6 is a fluorinated C 1-6 alkyl group or a fluorinated C 6 aryl group.
6 . The compound of claim 1 , wherein R 7 is a fluorine atom or is selected from fluorine substituted C 1-6 alkyl groups.
7 . The compound of claim 1 , wherein L 1 is a covalent bond or a linker selected from optionally substituted C 6 aryl groups.
8 . The compound of claim 1 , wherein X 1 is a carbon atom.
9 . The compound of claim 8 , wherein at least one of R 8 and R 9 is CN or optionally substituted C 1-6 alkyl.
10 . The compound of claim 8 , wherein R 8 and R 9 are both CN or optionally substituted C 1-6 alkyl.
11 . The compound of claim 8 , wherein R 8 and R 9 are both CN or are both fluorine substituted C 1-6 alkyl.
12 . The compound of claim 1 , wherein X 1 is a nitrogen atom.
13 . The compound of claim 12 , wherein R 9 is a fluorine substituted SO 2 alkyl.
14 . The compound of claim 13 , wherein Ro is SO 2 CF 3 .
15 . The compound of claim 1 , wherein M is Li. Na, or K and n is 1.
16 . The compound of claim 15 , wherein M is Li and n is 1.
17 . The compound of claim 1 , wherein said compound is selected from:
or a tautomer thereof.
18 . Electrode material comprising a compound as defined in claim 1 as an additive and at least one electrochemically active material.
19 . An electrolyte composition comprising a compound as defined in claim 1 .
20 . The electrolyte composition of claim 19 , further comprising a compatible solvent or a compatible solvating polymer.
21 . An electrochemical cell comprising an electrolyte, an electrode and a counter-electrode, wherein the electrode or counter-electrode comprises an electrode material as defined in claim 18 .
22 . An electrochemical cell comprising an electrolyte, an electrode and a counter-electrode, wherein the electrolyte comprises an electrolyte composition as defined in claim 19 .
23 . The electrochemical cell of claim 22 , wherein said electrochemical cell is a battery, an electrochromic device, or a capacitor.
24 . The electrochemical cell of claim 23 , wherein said battery is a lithium or lithium-ion battery.