Pyridine sulfur trioxide complexes as electrolyte component for high voltage batteries
An electrolyte composition including (i) at least one aprotic organic solvent; (ii) at least one conducting salt; (iii) at least one pyridine-SO 3 complex of formula (I) wherein R is selected independently at each occurrence from F, C 1 to C 10 alkyl, C 2 to C 10 alkenyl, and C 2 to C 10 alkynyl, wherein alkyl, alkenyl, and alkynyl may be substituted by one or more substituents selected from F and CN; and n is an integer selected from 1, 2, 3, 4, and 5; and (vi) optionally one or more additives; and its use in electrochemical cells.
1. An electrolyte composition, comprising:
(i) at least one aprotic organic solvent;
(ii) at least one conducting salt; and
(iii) at least one pyridine-SO 3 complex of formula (I)
wherein
R is selected independently at each occurrence from F, C 1 to C 10 alkyl, C 2 to C 10 alkenyl, and C 2 to C 10 alkynyl, wherein alkyl, alkenyl, and alkynyl may be substituted by one or more substituents selected from F and CN; and
n is an integer selected from 1, 2, 3, 4, and 5.
2. The electrolyte composition of claim 1 , wherein the electrolyte composition comprises 0.01 to 5 wt.-% of the at least one pyridine-SO 3 complex of formula (I), based on a total weight of the electrolyte composition.
3. The electrolyte composition of claim 1 , wherein at least one R is F.
4. The electrolyte composition of claim 1 , wherein n is 1 or 2.
5. The electrolyte composition of claim 1 , wherein at least one R is selected from C 2 to C 10 alkenyl which may be substituted by one or more substituents selected from F and CN.
6. The electrolyte composition of claim 1 , wherein at least one R is selected from C 2 to C 10 alkynyl which may be substituted by one or more substituents selected from F and CN.
7. The electrolyte composition of claim 1 , wherein at least one R is selected from C 1 to C 10 alkyl which may be substituted by one or more substituents selected from F and CN.
8. The electrolyte composition of claim 1 , wherein the at least one pyridine-SO 3 complex of formula (I) is selected from 2-vinyl pyridine sulfur trioxide, 3-vinyl pyridine sulfur trioxide, 4-vinyl pyridine sulfur trioxide, 2-trifluoromethyl pyridine sulfur trioxide, 3-trifluoromethyl pyridine sulfur trioxide, 4-trifluoromethyl pyridine sulfur trioxide, 2-fluoro pyridine sulfur trioxide, 3-fluoro pyridine sulfur trioxide, 4-fluoro pyridine sulfur trioxide, 2-propargyl pyridine sulfur trioxide, 3-propargyl pyridine sulfur trioxide, 4-propargyl pyridine sulfur trioxide, and mixtures thereof.
9. The electrolyte composition of claim 1 , wherein the at least one aprotic organic solvent (i) is selected from optionally fluorinated cyclic and acyclic organic carbonates, optionally fluorinated acyclic ethers and polyethers, optionally fluorinated cyclic ethers, optionally fluorinated cyclic and acyclic acetales and ketales, optionally fluorinated orthocarboxylic acids esters, optionally fluorinated cyclic and acyclic esters and diesters of carboxylic acids, optionally fluorinated cyclic and acyclic sulfones, optionally fluorinated cyclic and acyclic nitriles and dinitriles, optionally fluorinated cyclic and acyclic phosphates, and mixtures thereof.
10. The electrolyte composition of claim 1 , wherein the at least one aprotic organic solvent (i) is selected from optionally fluorinated C 1 -C 10 -alkylethers, optionally fluorinated cyclic and acyclic organic carbonates, and mixtures thereof.
11. The electrolyte composition of claim 1 , wherein the at least one conducting salt (ii) is selected from lithium salts.
12. The electrolyte composition of claim 1 , wherein the electrolyte composition further comprises at least one additive (iv) selected from the group consisting of film forming additives, flame retardants, overcharging additives, wetting agents, HF and/or H 2 O scavengers, stabilizers for LiPF 6 salt, ionic solvation enhancers, corrosion inhibitors, and gelling agents.
13. An electrochemical cell comprising:
an anode comprising an anode film; and
a cathode comprising a cathode film,
wherein the anode film and the cathode film each independently comprise the electrolyte composition of claim 1 .
14. An electrochemical cell, comprising:
an anode comprising a film forming additive; and
a cathode comprising the film forming additive,
wherein the film forming additive comprises a pyridine-SO 3 complex of formula (I)
wherein
R is selected independently at each occurrence from F, C 1 to C 10 alkyl, C 2 to C 10 alkenyl, and C 2 to C 10 alkynyl, wherein alkyl, alkenyl, and alkynyl may be substituted by one or more substituents selected from F and CN; and
n is an integer selected from 1, 2, 3, 4, and 5.