Oxiranyl ester derivatives as additive for electrolytes in lithium ion batteries

1. An electrolyte composition (A) comprising:

(i) an aprotic organic solvent;

(ii) a conducting salt;

(iii) a compound of formula (I)

wherein

R 1 is selected from the group consisting of C(O)C(O)OR 7 , S(O) 2 R 7 , S(O) 2 OR 7 , (CH 2 ) s SO 2 (CH 2 ) t R 7 , P(O)(OR 7 )R 7 , and P(O)(OR 7 ) 2 ;

R 2 is selected from the group consisting of H, F, C 1 -C 6 alkyl, C 3 -C 6 (hetero)cycloalkyl, C 2 -C 6 alkenyl, C 3 -C 6 (hetero)cycloalkenyl, C 2 -C 6 alkynyl, C 5 -C 7 (hetero)aryl, and C 6 -C 13 aralkyl, wherein alkyl, (hetero)cycloalkyl, aralkyl, alkenyl, (hetero)cycloalkenyl, alkynyl, and (hetero)aryl may be substituted by one or more substituents selected from the group consisting of F, CN, C 1 -C 6 alkyl, C 3 -C 6 (hetero)cycloalkyl, C 2 -C 6 alkenyl, C 5 -C 7 (hetero)aryl, OR 8 , C(O)R 8 , C(O)OR 8 , OC(O)R 8 , OC(O)OR 8 , OC(O)C(O)OR 8 , S(O) 2 OR 8 and OS(O) 2 R 8 ;

R 3 and R 4 are each independently selected from the group consisting of H, F, C 1 -C 6 alkyl, C 3 -C 6 (hetero)cycloalkyl, C 2 -C 6 alkenyl, C 3 -C 6 (hetero)cycloalkenyl, C 2 -C 6 alkynyl, C 5 -C 7 (hetero)aryl, and C 6 -C 13 aralkyl, wherein alkyl, (hetero)cycloalkyl, alkenyl, (hetero)cycloalkenyl, alkynyl, (hetero)aryl, and aralkyl, may be substituted by one or more substituents selected from the group consisting of F, CN, and optionally fluorinated oxiranyl;

R 5 and R 6 are each independently selected from the group consisting of H, C 1 -C 6 alkyl, C 3 -C 6 (hetero)cycloalkyl, C 2 -C 6 alkenyl, C 3 -C 6 (hetero)cycloalkenyl, C 2 -C 6 alkynyl, C 5 -C 7 (hetero)aryl, and C 6 -C 13 aralkyl, wherein alkyl, (hetero)cycloalkyl, aralkyl, alkenyl, (hetero)cycloalkenyl, alkynyl, and (hetero)aryl may be substituted by one or more substituents selected from the group consisting of F, CN, and optionally fluorinated oxiranyl;

R 7 is selected from the group consisting of C 1 -C 6 alkyl, C 3 -C 6 (hetero)cycloalkyl, C 2 -C 6 alkenyl, C 3 -C 6 (hetero)cycloalkenyl, C 2 -C 6 alkynyl, C 5 -C 7 (hetero)aryl, and C 6 -C 13 aralkyl, wherein alkyl, (hetero)cycloalkyl, aralkyl, alkenyl, (hetero)cycloalkenyl, alkynyl, and (hetero)aryl may be substituted by one or more substituents selected from the group consisting of F, CN, C 1 -C 6 alkyl, C 2 -C 6 alkenyl, C 5 -C 7 (hetero)aryl, OR 9 , OC(O)R 9 , C(O)R 9 , C(O)OR 9 , OC(O)OR 9 , OC(O)C(O)OR 9 , S(O) 2 OR 9 , OS(O) 2 R 9 , and C 3 -C 6 (hetero)cycloalkyl which may be substituted by one or more substituents selected from the group consisting of F, C 1 -C 6 alkyl, C 3 -C 6 (hetero)cycloalkyl, C 2 -C 6 alkenyl, C 3 -C 6 (hetero)cycloalkenyl, C 2 -C 6 alkynyl, C 5 -C 7 (hetero)aryl, and C 6 -C 13 aralkyl, wherein alkyl, (hetero)cycloalkyl, aralkyl, alkenyl, (hetero)cycloalkenyl, alkynyl, and (hetero)aryl may be substituted by one or more substituents selected from the group consisting of F, CN, and optionally fluorinated oxiranyl;

R 8 and R 9 are each independently selected from the group consisting of H, C 1 -C 6 alkyl, C 3 -C 6 (hetero)cycloalkyl, C 2 -C 6 alkenyl, C 3 -C 6 (hetero)cycloalkenyl, C 2 -C 6 alkynyl, C 5 -C 7 (hetero)aryl, and C 6 -C 13 aralkyl, wherein alkyl, (hetero)cycloalkyl, aralkyl, alkenyl, (hetero)cycloalkenyl, alkynyl, and (hetero)aryl may be substituted by one or more substituents selected from the group consisting of F, CN, and optionally fluorinated oxiranyl;

wherein s and t are independently from each other 1, 2, or 3; and

(iv) optionally a further additive.

2. The electrolyte composition (A) according to claim 1 wherein R 1 is C(O)C(O)OR 7 .

3. The electrolyte composition (A) according to claim 1 wherein R 1 is selected from the group consisting of S(O) 2 R 7 , S(O) 2 OR 7 , (CH 2 ) m SO 2 (CH 2 ) n R 7 , wherein m and n are independently from each other 1, 2, or 3, P(O)(OR 7 )R 7 , and P(O)(OR 7 ) 2 .

4. The electrolyte composition (A) according to claim 1 , wherein the compound of formula (I) comprises at least two oxirane cycles.

5. The electrolyte composition (A) according to claim 1 , wherein R 7 comprises an oxirane cycle.

6. The electrolyte composition (A) according to claim 1 , wherein the compound of formula (I) has a formula (II)

wherein

R 1a is selected from the group consisting of —C(═O)—, —C(═O)O—, —C(═O)C(═O)O—, —C(═O)R 7a C(═O)O—, —S(O) 2 —, —S(O) 2 O—, —(CH 2 ) s SO 2 (CH 2 ) t O—, —P(O)(OR 7b )—, and —P(O)(OR 7b )O—;

R 2 , R 2a , R 3 , R 3a , R 4 , R 4a , R 5 , R 5a , R 6 and R 6a are each independently selected from the group consisting of H, F, C 1 -C 6 alkyl, C 3 -C 6 (hetero)cycloalkyl, C 2 -C 6 alkenyl, C 3 -C 6 (hetero)cycloalkenyl, C 2 -C 6 alkynyl, C 5 -C 7 (hetero)aryl, and C 6 -C 13 aralkyl, wherein alkyl, (hetero)cycloalkyl, aralkyl, alkenyl, (hetero)cycloalkenyl, alkynyl, and (hetero)aryl may be substituted by one or more substituents selected from the group consisting of F, CN, and optionally fluorinated oxiranyl;

R 7a is selected from the group consisting of C 1 -C 4 alkanediyl, C 2 -C 4 alkenediyl, C 2 -C 4 alkynediyl and 1,2-oxiranediyl;

R 7b is selected from the group consisting of C 1 -C 6 alkyl, C 3 -C 6 (hetero)cycloalkyl, C 2 -C 6 alkenyl, C 3 -C 6 (hetero)cycloalkenyl, C 2 -C 6 alkynyl, C 5 -C 7 (hetero)aryl, and C 6 -C 13 aralkyl, wherein alkyl, (hetero)cycloalkyl, aralkyl, alkenyl, (hetero)cycloalkenyl, alkynyl, and (hetero)aryl may be substituted by one or more substituents selected from the group consisting of F, CN, and optionally fluorinated oxiranyl, and wherein s and t are independently from each other 1, 2, or 3.

7. The electrolyte composition (A) according to claim 1 , wherein the aprotic organic solvent (i) is selected from the group consisting of:

(a) a cyclic or noncyclic organic carbonate, which may be partly halogenated,

(b) a di-C 1 -C 10 -alkylether, which may be partly halogenated,

(c) a di-C 1 -C 4 -alkyl-C 2 -C 6 -alkylene ether or polyether, which may be partly halogenated,

(d) a cyclic ether, which may be partly halogenated,

(e) a cyclic or acyclic acetal or ketal, which may be partly halogenated,

(f) an orthocarboxylic acid ester, which may be partly halogenated,

(g) a cyclic or noncyclic ester of a carboxylic acid, which may be partly halogenated,

(h) a cyclic or noncyclic sulfone, which may be partly halogenated,

(i) a cyclic or noncyclic nitrile or dinitrile, which may be partly halogenated, and

(j) an ionic liquid, which may be partly halogenated.

8. The electrolyte composition (A) according to claim 1 , wherein the conducting salt (ii) is selected from the group consisting of

Li[F 6-x P(C y F 2y+1 ) x ], wherein x is an integer in the range from 0 to 6 and y is an integer in the range from 1 to 20;

Li[B(R 9 ) 4 ], Li[B(R 9 ) 2 (OR 10 O)] and Li[B(OR 10 O) 2 ] wherein each R 9 is independently selected from the group consisting of F, Cl, Br, I, C 1 -C 4 alkyl, C 2 -C 4 alkenyl, and C 2 -C 4 alkynyl, wherein alkyl, alkenyl, and alkynyl may be substituted by one or more OR 11 , wherein R 11 is selected from the group consisting of C 1 -C 6 alkyl, C 2 -C 6 alkenyl, and C 2 -C 6 alkynyl, and (OR 10 O) is a bivalent group derived from a 1,2- or 1,3-diol, a 1,2- or 1,3-dicarboxlic acid or a 1,2- or 1,3-hydroxycarboxylic acid, wherein the bivalent group forms a 5- or 6-membered cycle via both oxygen atoms with the central B-atom;

LiClO 4 ; LiAsF 6 ; LiCF 3 SO 3 ; Li 2 SiF 6 ; LiSbF 6 ; LiAlC 4 ; Li[N(SO 2 F) 2 ]; lithium tetrafluoro (oxalato) phosphate; lithium oxalate; and

a salt of formula Li[X(C n F 2n+1 SO 2 ) m ], where m and n are defined as follows:

m=1 when X is oxygen or sulfur,

m=2 when X is nitrogen or phosphorus,

m=3 when X is carbon or silicon, and

n is an integer in the range from 1 to 20.

9. The electrolyte composition (A) according to claim 1 , comprising at least one further additive (iv) selected from the group consisting of vinylene carbonate, a derivative of vinylene carbonate, vinyl ethylene carbonate, a derivative of vinyl ethylene carbonate, methyl ethylene carbonate, a derivative of methyl ethylene carbonate, lithium (bisoxalato) borate, lithium difluoro (oxalato) borate, lithium tetrafluoro (oxalato) phosphate, lithium oxalate, 2-vinyl pyridine, 4-vinyl pyridine, a cyclic exo-methylene carbonate, a sultone, an organic ester of an inorganic acid, an acyclic or cyclic alkane having a boiling point at 1 bar of at least 36° C., and an aromatic compound, an optionally halogenated cyclic or acyclic sulfonylimide, an optionally halogenated cyclic or acyclic phosphate ester, an optionally halogenated cyclic or acyclic phosphine, an optionally halogenated cyclic or acyclic phosphite, an optionally halogenated cyclic or acyclic phosphazene, an optionally halogenated cyclic or acyclic silylamine, an optionally halogenated cyclic or acyclic halogenated ester, an optionally halogenated cyclic or acyclic amide, an optionally halogenated cyclic or acyclic anhydride, an ionic liquid and an optionally halogenated organic heterocycle.

10. The electrolyte composition (A) according to claim 1 , wherein the concentration of the compound of formula (I) is 0.001 to 10 wt.-% based on a total weight of the electrolyte composition (A).

11. An electrochemical cell comprising

(A) the electrolyte composition according to claim 1 ,

(B) a cathode comprising a cathode active material, and

(C) an anode comprising an anode active material.

12. The electrochemical cell according to claim 11 , wherein the electrochemical cell is a secondary lithium ion battery.