Abstract: An electrolyte solution contains a non-aqueous solvent and an alkali metal salt dissolved in the non-aqueous solvent. The non-aqueous solvent contains a linear carboxylate represented by the following formula: where R1 and R2 independently represent an aromatic group, an unsaturated aliphatic group, or a saturated aliphatic group. A battery includes the electrolyte solution, a positive electrode containing a positive electrode active material that has a property of occluding and releasing an alkali metal ion, and a negative electrode containing an alkali metal or a negative electrode active material that has a property of occluding and releasing the alkali metal ion.

Abstract: An electrolyte solution contains a non-aqueous solvent and an alkali metal salt dissolved in the non-aqueous solvent. The non-aqueous solvent contains cyclopropanecarbonitrile. A battery includes an electrolyte solution which contains a non-aqueous solvent containing cyclopropanecarbonitrile and an alkali metal salt dissolved in the non-aqueous solvent, a positive electrode containing a positive electrode active material that has a property of occluding and releasing an alkali metal ion, and a negative electrode containing an alkali metal or a negative electrode active material that has a property of occluding and releasing the alkali metal ion.

Abstract: A non-aqueous electrolytic solution of the present invention includes: a solvent component including a glyme solvent and a phosphazene solvent; and an alkali metal salt composed of an alkali metal cation and an anion, the alkali metal salt being dissolved in the solvent component. The phosphazene solvent is a cyclic phosphazene compound represented by the formula (1). where X1 to X6 each independently represent a halogen atom or OR1, R1 is a substituted or unsubstituted aromatic group or a substituted or unsubstituted saturated aliphatic group, the aromatic group and the saturated aliphatic group each optionally contain a halogen atom, a nitrogen atom, an oxygen atom, a sulfur atom, or a silicon atom, and the saturated aliphatic group is linear or cyclic.

Abstract: A nonaqueous electrolyte solution for a secondary battery includes: a nonaqueous solvent including a cyclic carbonate having at least one fluoro group on a side chain thereof, a chain carbonate, and trimethylacetonitrile; and a lithium salt dissolved in the nonaqueous solvent.

Abstract: A sodium secondary battery includes a positive electrode, a negative electrode, and a non-aqueous electrolytic solution including a non-aqueous solvent. The non-aqueous solvent includes a fluoro group-containing chain carboxylic acid ester represented by General Formula (1): wherein R1 is an aromatic group, an unsaturated aliphatic group or a saturated aliphatic group; R2, R3 and R4 are each a hydrogen atom, an aromatic group, an unsaturated aliphatic group or a saturated aliphatic group; and at least one of R1, R2, R3 and R4 includes one or more fluoro groups.