Nonaqueous electrolyte and secondary battery containing same
Provided is a non-aqueous electrolyte for a secondary battery including a non-aqueous solvent, a solute dissolved in the non-aqueous solvent, and an additive, in which the additive includes an unsaturated chain hydrocarbon compound having two or more carbon-carbon unsaturated bonds and including a main chain having five or more carbon atoms. The unsaturated chain hydrocarbon compound preferable as the additive is 1,3-hexadiene or 2,4-hexadiene. The amount of the unsaturated chain hydrocarbon compound is preferably 0.1 to 10 parts by weight per 100 parts by weight of the non-aqueous solvent.
1 . A non-aqueous electrolyte for a secondary battery comprising:
a non-aqueous solvent,
a solute dissolved in said non-aqueous solvent, and
an additive,
wherein said additive comprises an unsaturated chain hydrocarbon compound having two or more carbon-carbon unsaturated bonds and including a main chain having five or more carbon atoms.
2 . The non-aqueous electrolyte in accordance with claim 1 , wherein said unsaturated chain hydrocarbon compound is represented by the general formula (1):
wherein each of R 1 , R 2 , R 3 , R 4 , R 5 and R 6 independently represents a hydrogen atom or an alkyl group having one to five carbon atoms, and at least one of R 1 to R 6 is an alkyl group whose main chain has five or more carbon atoms.
3 . The non-aqueous electrolyte in accordance with claim 2 , wherein said unsaturated chain hydrocarbon compound is 1,3-hexadiene or 2,4-hexadiene.
4 . The non-aqueous electrolyte in accordance with any one of claims 1 to 3 , wherein an amount of said unsaturated chain hydrocarbon compound is 0.1 to 10 parts by weight per 100 parts by weight of said non-aqueous solvent.
5 . The non-aqueous electrolyte in accordance with claim 1 , wherein said additive further comprises at least one selected from the group consisting of vinylene carbonate and vinyl ethylene carbonate.
6 . The non-aqueous electrolyte in accordance with claim 1 , wherein said solute comprises lithium tetrafluoroborate (LiBF 4 ).
7 . A non-aqueous electrolyte secondary battery comprising:
a positive electrode capable of absorbing and desorbing lithium,
a negative electrode capable of absorbing and desorbing lithium,
a separator interposed between said positive electrode and said negative electrode, and
the non-aqueous electrolyte in accordance with claim 1 .