Nonaqueous electrolyte solution and lithium secondary battery using same

Abstract

A nonaqueous electrolyte solution having high capacity and excellent storage characteristics and cycle characteristics is disclosed which enables to suppress gas generation. Specifically disclosed is a nonaqueous electrolyte solution containing a lithium salt and a nonaqueous solvent which also contains 0.01-8 weight% of a cyclic carbonate compound having an unsaturated bond and 0.01-5 weight% of a compound represented by the following general formula (Ia). (In the formula, R<11> and R<12> independently represent an organic group composed of carbon atoms and hydrogen atoms which may further contain an oxygen atom but does not contain an unsaturated bond; and at least one of R<11> and R<12> has an ether bond; R<11> and R<12> have 3-18 carbon atoms in total while having 1-6 oxygen atoms in total.

Description

Technical field [0001] The present invention relates to a non-aqueous electrolyte and a lithium secondary battery using the non-aqueous electrolyte. Background technique [0002] In many application fields, from so-called residential power sources such as portable phones and notebook computers to vehicle power sources used to drive automobiles, non-aqueous electrolyte batteries such as lithium secondary batteries have been put into practical use. However, in recent years, there has been an increasing demand for higher performance of non-aqueous electrolyte batteries. In addition to high capacity and good high-temperature storage characteristics, it is also required to have excellent cycle characteristics. [0003] Therefore, in order to obtain a high-capacity non-aqueous electrolyte battery, current design methods usually try to fill the limited battery volume with as much active material as possible. For example, in the method, pressure is applied to the active material layer of...

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Problems solved by technology

[0021] However, regarding the secondary battery disclosed in Patent Document 1, which uses a non-aqueous electrolytic solution containing a double bond-bearing cyclic carbonate compound, although its cycle characteristics at room temperature are improved, the presence of The problem is that it increases the amount of gas generation in the continuous charge state due to impaired cycle characteristics at low temperatures

[0022] Regarding the non-aqueous electrolytic solution containing benzenesulfonyl fluoride or p-toluenesulfonyl fluoride disclosed in Patent Document 3, there is a problem that the continuous charging characteristics at high temperatures and the high-temperature storage characteristics are impaired

[0023] Regarding Patent Document 4, it only gives an example in which the amount of the fluorine-containing ether compound is 60% by weight to 70% by weight, and does not mention battery characteristics, so there is a problem that when it is actually used in a battery, Battery characteristics such as continuous charging characteristics will decrease

So, there is a problem that the continuous charging characteristics actually degrade

[0025] In addition, as described below, when the electrolyte solutions disclosed in Patent Document 4 and Patent Document 5 are used at high voltage, there is a problem that the battery deteriorates and battery characteristics deteriorate

When adopting a battery in a continuous state of charge at a high voltage, there is a problem that the electrode at a high potential reacts with the electrolyte, resulting in increased gas generation, battery deterioration, and shortened battery life

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