Abstract: A nonaqueous electrolyte secondary battery according to one aspect of the present invention has a positive electrode including a positive electrode active material which absorbs and releases lithium ions, a negative electrode including a negative electrode active material which absorbs and releases lithium ions, a separator, and a nonaqueous electrolyte. The positive electrode active material includes a lithium cobalt composite oxide containing at least aluminum (Al) and magnesium (Mg), the negative electrode active material includes at least one of metal silicon (Si) and a silicon oxide represented by SiOx (0.5?x<1.6), and the nonaqueous electrolyte contains as a nonaqueous solvent, ethylene carbonate, a lactone, and fluoroethylene carbonate.

Abstract: A non-aqueous electrolyte secondary battery comprising a positive electrode plate, a negative electrode plate, a separator, and a non-aqueous electrolyte, and the negative electrode active material is a mixture of a graphite material, and silicon or a silicon compound, and the separator is a polyolefin microporous film, which contains polyethylene as an essential component and is formed of a multilayer film having at least two layers, and the separator contains inorganic particles at least in the surface layer on the side facing the negative electrode plate.

Abstract: A non-aqueous electrolyte secondary battery system includes a non-aqueous electrolyte secondary battery and a charging control system which has a function of detecting the voltage of the non-aqueous electrolyte secondary battery and disconnecting a charging circuit. The non-aqueous electrolytic solution contains a non-aqueous solvent having a viscosity of 0.6 cP or less at 25° C. in an amount of 35 to 80 vol % inclusive as a non-aqueous solvent and also contains hexamethylene diisocyanate, and the charging control system stops charging when the potential of the positive electrode of the non-aqueous electrolyte secondary battery is 4.35 to 4.6 V inclusive based on lithium. Thus the non-aqueous electrolyte secondary battery system equipped with the non-aqueous electrolyte secondary battery having high charging potential and excellent high-temperature cycling characteristics can be provided.

Abstract: A non-aqueous electrolyte secondary battery comprising a positive electrode plate contains a positive electrode active material capable of absorbing and releasing lithium reversibly, a negative electrode plate containing a negative electrode active material capable of absorbing and releasing lithium reversibly, a separator keeping the positive electrode plate and the negative electrode plate isolated, and a non-aqueous electrolytic solution containing a non-aqueous solvent and an electrolyte salt, wherein the positive electrode plate has a surface on which an inorganic particle layer containing inorganic particles and a binder is formed, and the separator is a polyolefin microporous film including a laminate film having at least two layers and containing inorganic particles in at least a negative-electrode-side surface layer thereof. This configuration can improve storage properties and reduce swelling under high-temperature environment.

Abstract: A nonaqueous electrolyte secondary battery has a positive electrode plate containing a positive electrode active material capable of reversibly absorbing and desorbing lithium; a negative electrode plate containing a negative electrode active material capable of reversibly absorbing and desorbing lithium; a separator separating the positive electrode plate and the negative electrode plate; and a nonaqueous electrolyte solution obtained by dissolving a solute in an organic solvent, said solute being composed of a lithium salt. In this battery, a polyolefin microporous membrane is used as the separator formed of a multilayer film having two or more layers and at least one of two surface layers of said polyolefin microporous membrane containing inorganic particles.

Abstract: The nonaqueous electrolyte secondary battery includes a rolled electrode assembly 14E formed by rolling a positive electrode plate 11 and a negative electrode plate 12 with a separator 13 interposed therebetween, the separator 13 is fixed on the outermost periphery of the rolled electrode assembly 14E with an adhesive tape for fixing a roll end 30e, an exposed portion of a negative electrode substrate 12c without an active material mixture layer 12b is placed on an outermost periphery side of the negative electrode plate 12, a negative electrode tab 12a is connected to the negative electrode substrate 12c on an outermost periphery side, and the adhesive tape 30e is not overlapped with a roll end 11d of the positive electrode plate 11 and a roll end 12d of the negative electrode substrate 12c. Thus the battery is seldom broken even when charging and discharging are repeatedly provided at high voltage.

Abstract: The invention provides a method for evaluating the safety of a battery under an internal short-circuit condition. The battery includes: an electrode group including a positive electrode, a negative electrode, and an insulating layer for electrically insulating the electrodes, which are wound or laminated; an electrolyte; a housing for housing the electrode group and the electrolyte; and a current-collecting terminal for electrically connecting the electrode group and the housing. The method of the invention includes: placing a foreign object at a location inside the electrode group of the battery where the positive electrode and the negative electrode face each other; and pressing the location by the pressure applied by a pressing tool to locally crush the insulating layer between the positive and negative electrodes, thereby causing an internal short-circuit.

Abstract: A nonaqueous electrolyte secondary battery includes a positive electrode plate, a negative electrode plate, a separator, and a nonaqueous electrolytic solution. The separator is constituted of a polyolefin microporous membrane constituted of two or more layers of stacked film containing polyethylene and polypropylene, one or both of the surface layers has a polypropylene mixture proportion exceeding 50% by mass and contains inorganic particles, and the nonaqueous electrolytic solution contains a dinitrile compound expressed by CN—(CH2)n—CN (where n?1 and n is an integer). Thus, the nonaqueous electrolyte secondary battery that even when stored at high temperature in a charged state is not prone to positive electrode degradation and has a large post-high temperature storage capacity recovery rate and good cycling characteristics can be provided.

Abstract: A non-aqueous electrolyte secondary battery with excellent discharge cycle characteristics and a charging termination potential ranging from 4.4 to 4.6 V based on lithium, consisting of a positive electrode comprising a positive electrode active material, a negative electrode, and a non-aqueous electrolyte containing a non-aqueous solvent and an electrolyte salt, in which the positive electrode active material comprises a mixture of a lithium-cobalt composite oxide containing at least both zirconium and magnesium in LiCoO2, and a lithium-manganese-nickel composite oxide having a layered structure and containing at least both manganese and nickel, and the potential of the positive electrode active material ranges from 4.4 to 4.6 V based on lithium, and the non-aqueous electrolyte contains at least one of aromatic compounds selected from the group consisting at least of toluene derivatives, anisole derivatives, biphenyl, cyclohexyl benzene, tert-butyl benzene, tert-amyl benzene, and diphenyl ether.

Abstract: The present invention provides a nonaqueous electrolyte secondary battery that can be charged at high voltage and suppress capacity deterioration after charged storage in a high temperature environment. A nonaqueous electrolyte secondary battery 10 includes a positive electrode sheet 11, a negative electrode sheet 12, a nonaqueous electrolyte, and a separator 13, and the positive electrode active material has a potential of 4.35 to 4.60 V based on lithium. The positive electrode sheet 11 has a surface provided with an inorganic particle layer. The separator 13 has an average pore size of 0.15 ?m or more and 0.3 ?m or less. It is preferable that the inorganic particle layer provided to the surface of the positive electrode sheet 11 contain titanium oxide or aluminum oxide.

Abstract: A non-aqueous electrolyte secondary cell can be charged at a high voltage of 4.3V or more and has excellent cycle characteristics and excellent high-temperature storage characteristics. The cell includes positive and negative electrodes capable of inserting and extracting lithium, and a non-aqueous electrolyte. The non-aqueous electrolyte contains a non-aqueous solvent, 1,3-dioxane and a dinitrile compound additives, and an electrolyte salt. The non-aqueous solvent contains ethylene carbonate in the range of 25% to 40% by volume under the conditions of 25° C. and 1 atm.

Abstract: A non-aqueous electrolyte secondary battery has a high initial capacity and excels in cycle characteristics and storage characteristics even when charged until the potential of the positive electrode active material exceeds as high as 4.3V versus lithium. The non-aqueous electrolyte of the secondary battery contains both 1,3-dioxane and a sulfonic acid ester compound.

Abstract: A nonaqueous electrolyte secondary battery of the invention has a positive electrode having a positive electrode active material, a negative electrode, and a nonaqueous electrolyte having electrolyte salt in a nonaqueous solvent. The electric potential of the positive electrode active material is 4.4 to 4.6 V relative to lithium, and the nonaqueous electrolyte contains a compound expressed by structural formula (I) below. The quantity of compound added is preferably 0.1% to 2% by mass. Also, the positive electrode active material preferably comprises a mixture of a lithium-cobalt composite oxide which is LiCoO2 containing at least both zirconium and magnesium and a lithium-manganese-nickel composite oxide that has a layer structure and contains at least both manganese and nickel. Thanks to such structure, a nonaqueous electrolyte secondary battery can be provided that is charged to charging termination potential of 4.4 to 4.6 V relative to lithium and that has enhanced overcharging safety.

Abstract: A nonaqueous electrolyte secondary battery includes a positive electrode plate, a negative electrode plate, a separator, and a nonaqueous electrolytic solution. The separator is constituted of a polyolefin microporous membrane constituted of two or more layers of stacked film containing polyethylene and polypropylene, one or both of the surface layers has a polypropylene mixture proportion exceeding 50% by mass and contains inorganic particles, and the nonaqueous electrolytic solution contains a dinitrile compound expressed by CN—(CH2)n—CN (where n?1 and n is an integer). Thus, the nonaqueous electrolyte secondary battery that even when stored at high temperature in a charged state is not prone to positive electrode degradation and has a large post-high temperature storage capacity recovery rate and good cycling characteristics can be provided.

Abstract: The preservation performance of a nonaqueous electrolyte secondary cell charged to high potential is improved while the initial capacity and the cycle property of the cell are also improved. The nonaqueous electrolyte secondary cell includes: a positive electrode having lithium phosphate and a positive electrode active material containing lithium cobalt compound oxide and lithium manganese nickel compound oxide having a layer structure, the lithium cobalt compound oxide having at least zirconium and magnesium added in LiCoO2; a negative electrode having a negative electrode active material; and a nonaqueous electrolyte having a nonaqueous solvent and an electrolytic salt. The potential of the positive electrode is more than 4.3 V and 5.1 V or less based on lithium. The nonaqueous electrolyte contains vinylene carbonate as the nonaqueous solvent and, as the electrolytic salt, at least one of lithium bis(pentafluoroethane sulfonyl)imide and lithium bis(trifluoromethane sulfonyl)imide at 0.1 M or more and 0.

Abstract: A non-aqueous electrolyte secondary cell superior in resistance against continuous charging at high potential is provided. The non-aqueous electrolyte secondary cell includes: a positive electrode having lithium phosphate and a positive electrode active material comprising lithium cobalt oxide containing at least one selected from Mg, Al, Ti, and Zr; and a separator having pores having an average diameter of 0.05 to 0.2 ?m.

Abstract: A positive electrode active material of a nonaqueous electrolyte secondary battery is composed of lithium-cobalt composite oxide containing at least one of zirconium, titanium, aluminum, and erbium, and the nonaqueous electrolyte includes an additive expressed by General Formula (1) having an acetylene group and a methylsulfonyl group at each end of the molecule. It has the effect of forming an SEI surface film as with the case of VC or the like, as well as having a higher oxidation resistance than that of VC or the like. Thus the nonaqueous electrolyte secondary battery employing as positive electrode active material a lithium-cobalt composite oxide with a particular dissimilar metallic element added, in which decomposition of the nonaqueous electrolytic solution during storage at high temperature in a charged state is suppressed, and there is little battery swelling is provided.

Abstract: The evaluation method of a separator for a nonaqueous electrolyte battery according to the present invention includes: placing opposite an upper jig 21 serving also as a conductive electrode and a lower jig 23 serving also as a conductive electrode in both sides of the separator sample 22; and measuring the relationship between an applied voltage and a passed current between the upper jig 21 and the lower jig 23 while applying a pressure to between the upper jig 21 and the lower jig 23 to evaluate the separator. At this time, by fitting a foreign material 28 in any shape between the separator sample 22 and one of the upper jig 21 and the lower jig 23, an evaluation of the separator simulating the presence of a foreign material affecting adversely the separator can be performed.

Abstract: The nonaqueous electrolyte secondary battery having high output characteristics and excellent safety when overcharging as well as excellent charge and discharge cycle characteristics according to an aspect of the invention includes a positive electrode having a positive electrode active material, a negative electrode having a negative electrode active material, a separator, and a nonaqueous electrolyte. The positive electrode active material includes lithium iron phosphate having an olivine crystal structure represented by General Formula LixFePO4 (where x is 0<x<1.3), the negative electrode active material includes a carbon material having an average operating potential of 0.3 V or less based on lithium in a range of 10 to 30% depth of discharge at the time of discharging at 6 mA/cm2, and the nonaqueous electrolyte includes an alkoxybenzene derivative within a range of 0.1 to 5.0% by mass.

Abstract: The nonaqueous electrolyte secondary battery includes a rolled electrode assembly 14E formed by rolling a positive electrode plate 11 and a negative electrode plate 12 with a separator 13 interposed therebetween, the separator 13 is fixed on the outermost periphery of the rolled electrode assembly 14E with an adhesive tape for fixing a roll end 30e, an exposed portion of a negative electrode substrate 12c without an active material mixture layer 12b is placed on an outermost periphery side of the negative electrode plate 12, a negative electrode tab 12a is connected to the negative electrode substrate 12c on an outermost periphery side, and the adhesive tape 30e is not overlapped with a roll end 11d of the positive electrode plate 11 and a roll end 12d of the negative electrode substrate 12c. Thus the battery is seldom broken even when charging and discharging are repeatedly provided at high voltage.