Non-aqueous electrolytic solution for lithium secondary battery or lithium ion capacitor, and lithium secondary battery or lithium ion capacitor using the same
摘要
說明書
Recently, lithium secondary batteries or lithium ion capacitors have come to be widely used not only as the power sources for small electronic devices such as cellular phones and notebook personal computers, but also as vehicle-mounted power sources for electric vehicles or for stopping idling, and as power sources for power storage. For these electric vehicles, for the purpose of extending the cruising distance, energy storage devices have been undergoing the achievement of further higher voltages or the achievement of further higher energy densities. Consequently, the travel distances of electric vehicles have been extended, and electric vehicles are possibly going to be used in regions widely varied in temperature from very hot regions such as tropical regions to very cold regions. Therefore, these lithium secondary batteries or these lithium ion capacitors experience 60° C. or higher in vehicles under blazing sun. Alternatively, at a very low temperature as frigid as ?40° C. or lower, the non-aqueous electrolytic solution possibly freezes. Accordingly, these lithium secondary batteries or these lithium ion capacitors are required to be capable of being used with the liquid state being maintained and exhibiting excellent battery performances even when used in “a wide temperature range extending over a temperature width of 100° C.” from a high temperature of 60° C. to a very low temperature as low as ?40° C. or lower.
A lithium secondary battery is mainly constituted with a positive electrode and a negative electrode, each mainly including a material capable of occluding and releasing lithium, and a non-aqueous electrolytic solution composed of a lithium salt and a non-aqueous solvent; as the non-aqueous solvent, carbonates such as ethylene carbonate (EC) and dimethyl carbonate (DMC) are used.
