Gs Yuasa International Ltd.

Robert Boschgmbh

Yudai Kawasoe

Katsushi Nishie

Kenta Nagamine

Tomonori Kako

Shinya Kitano

Keisuke Anami

Takeshi Hachida

Sumio Mori

Tetsuhiro Kobayashi

One aspect of the present invention is an energy storage device including: an electrode assembly including a negative electrode and a positive electrode that are stacked on each other with a separator interposed therebetween; a nonaqueous electrolyte containing a nonaqueous solvent; and a flat outer case housing the electrode assembly and the nonaqueous electrolyte, wherein the electrode assembly is disposed in the outer case in a compressed state so that the electrode assembly is pressurized in a direction of stack, a surface pressure acting on the outer case in the direction of stack is 1 k Pa or more, the nonaqueous solvent contains a fluorinated cyclic carbonate, and the nonaqueous electrolyte has an electric conductivity at 25° C. of 0.75 S/m or more.

Energy storage device

A nonaqueous electrolyte secondary battery disclosed herein includes a positive electrode plate including a positive composite layer, a negative electrode plate including a negative composite layer, and a nonaqueous electrolyte, in which the negative composite layer is composed of a facing portion facing a surface of the positive composite layer, and a non-facing portion that is on the same surface as the facing portion and does not face the surface of the positive composite layer, and the area ratio of the non-facing portion to a combined area of the facing portion and the non-facing portion of the negative composite layer is 7% or more, and the nonaqueous electrolyte contains a fluorinated carbonate and a cyclic sulfone compound.

Nonaqueous electrolyte secondary battery

Provided are a nonaqueous electrolyte capable of providing a nonaqueous electrolyte energy storage device with reduced direct current resistance and an increased capacity retention ratio after charge-discharge cycles, a nonaqueous electrolyte energy storage device including such a nonaqueous electrolyte, and a method for producing such a nonaqueous electrolyte energy storage device. One mode of the present invention is a nonaqueous electrolyte for an energy storage device, containing an additive represented by the following Formula (1) or Formula (2). In Formula (1), Rto Rare each independently a hydrogen atom or a group represented by &#x2014;NR, &#x2014;OR, &#x2014;SR, etc., with the proviso that at least one of Rto Ris a group represented by &#x2014;OR, &#x2014;SR, &#x2014;COOR, &#x2014;COR, &#x2014;SOR, or &#x2014;SOR. In Formula (2), Rto Rare each independently a hydrogen atom or a group represented by &#x2014;NR, &#x2014;OR, or &#x2014;SR, with the proviso that at least one of Rto Ris a group represented by &#x2014;SR.

Nonaqueous electrolyte, nonaqueous electrolyte energy storage device, and method for producing nonaqueous electrolyte energy storage device

A nonaqueous electrolyte secondary battery includes a positive electrode, a negative electrode, and a nonaqueous electrolyte. A positive electrode charge potential is 3.7 V or less with respect to a lithium metal potential. The nonaqueous electrolyte includes a cyclic disulfone compound having a specific structure in an amount of 0.1 to 4.0% by mass based on a total mass of the nonaqueous electrolyte.

Nonaqueous electrolyte secondary battery and method for producing nonaqueous electrolyte secondary battery

An object of the present invention is to provide a nonaqueous electrolyte secondary battery including a monofluorotoluene-containing nonaqueous electrolyte with an improved overcharge-preventing effect. In a monofluorotoluene-containing nonaqueous electrolyte, when a specific fluorophosphate compound is contained, the overcharge-preventing effect of the monofluorotoluene can be improved. As a result, in the overcharged state of a nonaqueous electrolyte secondary battery including the monofluorotoluene-containing nonaqueous electrolyte, an increase in the battery surface temperature can be suppressed.

A nonaqueous electrolyte secondary battery includes a positive electrode, a negative electrode and an electrolyte solution, wherein the negative electrode includes a negative active material layer, the electrolyte solution contains fluoroethylene carbonate, and when a content (mg) of the fluoroethylene carbonate is denoted as X and a reaction area (m) of the negative active material layer is denoted as Y, X and Y satisfy a relation of 10&#x2266;(X/Y)&#x2266;100.

A nonaqueous electrolyte secondary battery including a positive electrode having a positive active material, and an electrolyte, wherein a positive electrode potential at the time of charging is 3.7 V or less with respect to a lithium metal potential, and the electrolyte contains a cyclic sulfate compound having a specific structure.

A nonaqueous electrolyte secondary battery includes a positive electrode, a negative electrode and a nonaqueous electrolyte. The positive electrode includes LiMnNiCoMO(0&#x3c;x&#x3c;1.3, 0.1&#x3c;a&#x3c;0.7, 0.1&#x3c;b&#x3c;0.6, 0.1&#x3c;c&#x3c;0.67, 0&#x2266;d&#x3c;0.1, a+b+c+d=1, and M represents a metal selected from the group consisting of Al, Ti, Mg, Cr, Zn, W, Zr and Nb) as a positive active material. The nonaqueous electrolyte includes a cyclic disulfone compound of the general formula (1) in an amount of 0.1 to 4.0% by mass based on the total mass of the nonaqueous electrolyte.

A non-aqueous electrolyte secondary battery includes a positive electrode containing a positive-electrode active material, a negative electrode containing a negative-electrode active material, and a non-aqueous electrolyte, and is characterized in that the non-aqueous electrolyte contains 1.0 wt % or less of a compound represented by formula (1) and 2.0 wt % or less of a cyclic sulfate ester represented by formula (2), based on the total weight of the non-aqueous electrolyte. By using the non-aqueous electrolyte including a specified amount of the compound represented by formula (1) and a specified amount of the cyclic sulfate ester, when the battery is used at a low temperature after being stored at a high temperature, the increase of the internal resistance is inhibited.

Non-aqueous electrolyte secondary battery, and method for fabricating non-aqueous electrolyte secondary battery

A non-aqueous electrolyte secondary battery is described, capable of inhibiting the raise of the internal resistance at a low temperature after use in a high-temperature circumstance, and having a good power performance at a low temperature. The non-aqueous electrolyte secondary battery has a non-aqueous electrolyte, and is characterized in containing a sulfate ester with a specific structure in an amount of 4.0 wt % or less relative to the total weight of the non-aqueous electrolyte.

Growing community of inventors

Kyoto, Japan

Yudai Kawasoe