ESTER COMPOUND, AND NON-AQUEOUS ELECTROLYTE SOLUTION AND LITHIUM SECONDARY BATTERY EACH USING THE ESTER COMPOUND

• US 20100119955A1
• Filed: 02/01/2008
• Published: 05/13/2010
• Est. Priority Date: 02/02/2007
• Status: Active Grant

• Current Assignee: MU Ionic Solutions Corporation
• Original Assignee: UBE Industries Limited (UBE Corporation)
• Inventors: Hashimoto, Chisen, Abe, Koji
• Granted Patent: US 8,263,268 B2
• Time in Patent Office: Days
• US Class Current: 429/338
• CPC Class Codes: C07C 69/92 with etherified hydroxyl groups
• CPC Class Codes: H01M 10/052 Li-accumulators
• CPC Class Codes: H01M 10/0567 characterised by the additives
• CPC Class Codes: H01M 2300/0025 Organic electrolyte
• CPC Class Codes: H01M 2300/0042 Four or more solvents
• CPC Class Codes: Y02E 60/10 Energy storage using batteries

Abstract

The present invention includes (1) an ester compound having a specific structure, (2) a nonaqueous electrolytic solution for lithium secondary battery comprising an electrolyte dissolved in a nonaqueous solvent and containing an ester compound having a specific structure in an amount of from 0.01 to 10% by weight of the nonaqueous electrolytic solution, which is excellent in initial battery capacity and cycle property, and (3) a lithium secondary battery comprising a positive electrode, a negative electrode and a nonaqueous electrolytic solution of an electrolyte salt dissolved in a nonaqueous solvent, wherein the nonaqueous electrolytic solution contains an ester compound having a specific structure in an amount of from 0.01 to 10% by weight of the nonaqueous electrolytic solution.

Claims

1. An ester compound represented by the following general formula (I) or (II):

wherein R¹ represents a methoxy group or an ethoxy group; and

R² represents a linear or branched alkenyl group having from 2 to 6 carbon atoms, a linear or branched alkynyl group having from 3 to 6 carbon atoms, a phenyl group or a biphenyl group;

wherein R³ represents a methoxy group or an ethoxy group; and

L¹ represents a linear or branched alkylene group having from 2 to 6 carbon atoms, a linear or branched alkenylene group having from 4 to 6 carbon atoms, or a linear or branched alkynylene group having from 4 to 6 carbon atoms.

2. The ester compound according to claim 1, wherein, in the general formula (I), R¹ is a methoxy group, and R² is a vinyl group, an allyl group, a propargyl group, a phenyl group or a biphenyl group.

3. A nonaqueous electrolytic solution for a lithium secondary battery, comprising an electrolyte dissolved in a nonaqueous solvent and containing an ester compound represented by the following general formula (III) in an amount of from 0.01 to 10% by weight of the nonaqueous electrolytic solution:

wherein R¹¹, R¹³, R¹⁴ and R¹⁵ each independently represent a hydrogen atom or a fluorine atom;

R¹² represents a hydrogen atom, a fluorine atom, a methoxy group or an ethoxy group;

at least one of R¹¹ to R¹⁵ is a fluorine atom;

L² represents an alkyl group having from 1 to 6 carbon atoms, an alkenyl group having from 2 to 6 carbon atoms, an alkynyl group having from 3 to 6 carbon atoms, a phenyl group or a biphenyl group;

provided that when all of R¹¹ to R¹⁵ are fluorine atoms, then L² represents an alkenyl group having from 2 to 6 carbon atoms, an alkynyl group having from 3 to 6 carbon atoms, a phenyl group or a biphenyl group.

4. The nonaqueous electrolytic solution for a lithium secondary battery according to claim 3, wherein, in the general formula (III), L² is a vinyl group, an allyl group or a propargyl group.

5. The nonaqueous electrolytic solution for a lithium secondary battery according to claim 3, wherein, in the general formula (III), at least two of R¹¹, R¹³ and R¹⁵ are fluorine atoms.

6. The nonaqueous electrolytic solution for a lithium secondary battery according to claim 3, wherein the electrolytic solution contains at least two selected from ethylene carbonate, propylene carbonate, vinylene carbonate and fluoroethylene carbonate.

7. A nonaqueous electrolytic solution comprising an electrolyte salt dissolved in a nonaqueous solvent and containing an ester compound represented by the following general formula (II) and/or (IV) in an amount of from 0.01 to 10% by weight of the nonaqueous electrolytic solution:

wherein R³, represents a methoxy group or an ethoxy group; and

L¹ represents a linear or branched alkylene group having from 2 to 6 carbon atoms, a linear or branched alkenylene group having from 4 to 6 carbon atoms, or a linear or branched alkynylene group having from 4 to 6 carbon atoms;

wherein R⁴ represents a methoxy group or an ethoxy group; and

R⁵ represents a linear or branched alkyl group having from 1 to 6 carbon atoms, a linear or branched alkenyl group having from 2 to 6 carbon atoms, a linear or branched alkynyl group having from 3 to 6 carbon atoms, a phenyl group or a biphenyl group.

8. The nonaqueous electrolytic solution according to claim 7, wherein, in the general formula (IV), R⁴ is a methoxy group, and R⁵ is a methyl group, an ethyl group, a vinyl group, an allyl group, a propargyl group, a phenyl group or a biphenyl group.

9. A lithium secondary battery comprising a positive electrode, a negative electrode and a nonaqueous electrolytic solution of an electrolyte salt dissolved in a nonaqueous solvent, wherein the nonaqueous electrolytic solution contains at least one ester compound selected from those of general formulae (II), (III) and (IV) in an amount of from 0.01 to 10% by weight of the nonaqueous electrolytic solution:

wherein R3 represents a methoxy group or an ethoxy group; and

L¹ represents a linear or branched alkylene group having from 2 to 6 carbon atoms, a linear or branched alkenylene group having from 4 to 6 carbon atoms, or a linear or branched alkynylene group having from 4 to 6 carbon atoms;

wherein R¹¹, R¹³, R¹⁴ and R¹⁵ each independently represent a hydrogen atom or a fluorine atom;

R¹² represents a hydrogen atom, a fluorine atom, a methoxy group or an ethoxy group;

at least one of R¹¹ to R¹⁵ is a fluorine atom;

L² represents an alkyl group having from 1 to 6 carbon atoms, an alkenyl group having from 2 to 6 carbon atoms, an alkynyl group having from 3 to 6 carbon atoms, a phenyl group or a biphenyl group;

provided that when all of R¹¹ to R¹⁵ are fluorine atoms, then L² represents an alkenyl group having from 2 to 6 carbon atoms, an alkynyl group having from 3 to 6 carbon atoms, a phenyl group or a biphenyl group;

wherein R⁴ represents a methoxy group or an ethoxy group; and

R⁵ represents a linear or branched alkyl group having from 1 to 6 carbon atoms, a linear or branched alkenyl group having from 2 to 6 carbon atoms, a linear or branched alkynyl group having from 3 to 6 carbon atoms, a phenyl group or a biphenyl group.