Nonaqueous electrolytic solution and nonaqueous electrolyte secondary battery

Abstract

A nonaqueous electrolytic solution that can provide a high energy density nonaqueous electrolyte secondary battery having a high capacity, excellent storage characteristics, and excellent cycle characteristics and suppressing the decomposition of an electrolytic solution and the deterioration thereof when used in a high-temperature environment includes an electrolyte, a nonaqueous solvent, and a compound represented by general formula (1):wherein R1, R2, and R3 each independently represent a hydrogen atom, a cyano group, or an optionally halogen atom-substituted hydrocarbon group having 1 to 10 carbon atoms, with the proviso that R1 and R2 do not simultaneously represent hydrogen atoms.

Description

TECHNICAL FIELD[0001]The present invention relates to nonaqueous electrolytic solutions and nonaqueous electrolyte secondary batteries. Specifically, the present invention relates to a specific component-containing nonaqueous electrolytic solution that can realize a secondary battery having improved battery characteristics, such as cycle characteristics and high-temperature storage characteristics, and relates to a nonaqueous electrolyte secondary battery including the nonaqueous electrolytic solution.BACKGROUND ART[0002]In recent years, there have been advances in the development of nonaqueous electrolyte secondary batteries with higher energy densities as progress toward a reduction in the size and weight of electric appliances. Furthermore, the expansion of fields of application of nonaqueous electrolyte secondary batteries require further improvement in battery characteristics.[0003]Hitherto, metallic lithium, metal compounds, such as elemental metals, oxides, and alloys of lith...

AI Technical Summary

Benefits of technology

The present invention aims to address the issues with traditional graphite negative electrodes in nonaqueous electrolyte secondary batteries. The invention provides a solution to reduce the decomposition reaction of the electrolytic solution and additives, leading to improved charge and discharge efficiency, storage characteristics, and cycle characteristics. The use of a nitrile compound with a specific structure and an additive for forming a film on the negative electrode minimized the decomposition reaction and, thus, enhanced the performance of the electrodes in high-temperature environments.

Problems solved by technology

However, the performance, in particular, discharge capacity retention rates of the secondary batteries in charge-discharge cycles over longer periods of time, is still insufficient.

Furthermore, the conventional secondary batteries described above do not sufficiently overcome all problems of gas generation, the reduction in cycle characteristics, and the like when stored in a charged state at a high temperature.

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