Abstract: A secondary-battery internal short detection apparatus is provided which is capable of precisely detecting an internal short being generated in a secondary-battery.

Abstract: In a lithium ion secondary battery including a positive electrode, a negative electrode containing an alloy-based negative electrode active material, a separator, a positive electrode lead, a negative electrode lead, a gasket, and an outer case, the positive electrode is allowed to contain an oxygen deficient non-stoichiometric oxide, or an oxygen removing layer containing an oxygen deficient non-stoichiometric oxide is provided between the positive electrode and the separator. In a lithium ion secondary battery containing the alloy-based negative electrode active material, a reaction between oxygen generated in the positive electrode and the alloy-based negative electrode active material, and heat generation accompanying the reaction are prevented.

Abstract: A lithium secondary battery of this invention includes: a positive electrode including a positive electrode active material; a negative electrode including a negative electrode active material; a separator; and a non-aqueous electrolyte. The negative electrode active material includes a first portion capable of absorbing and desorbing lithium ions and a second portion covering at least a part of a surface of the first portion. The second portion includes at least one material that is less reactive with oxygen than the first portion.

Abstract: In a lithium ion secondary battery including a flat-plate electrode assembly which is configured by stacking the positive electrode, the separator, and the negative electrode in the thickness direction thereof, each of the positive electrode and the negative electrode includes a current collector and an active material layer. Each of the current collector includes a substantially rectangular current collector body, a heat radiating portion, and a lead portion, and the heat radiating portions are projected toward the outside of the electrode assembly so as not to overlap with each other in the thickness direction of the electrode assembly. In this way, heat caused inside the lithium ion secondary battery can be diffused efficiently to the outside, and safety of the lithium ion secondary battery can be further increased, without complicating the battery structure and decreasing mechanical strength of the battery.

Abstract: In a driving device that includes a mechanical oil pump operated by power of an engine and a motor oil pump EOP operated by power of a motor, provided in parallel with each other, and check valves on discharge sides of the pumps, and pumps oil from any of the pumps and supplies the oil to a clutch included in a transmission, a through hole 68a for releasing air that communicates with a discharge port 68 is formed in a case 61 of the mechanical oil pump MOP. This allows air trapped in when driving of the mechanical oil pump MOP is started along with a start of the engine to be quickly discharged to quickly increase internal pressure to pressure required for opening the check valve, and thus oil can be supplied to the clutch of the transmission via the check valve to quickly operate the clutch.

Abstract: A lithium ion secondary battery includes a negative electrode that is shaped like waves in a section in the thickness direction. In the negative electrode, the ratio t1/t0 of the largest thickness t1 to the smallest thickness t0 is from 1.2 to 3.0. The negative electrode includes a thin-film negative electrode active material layer in which the ratio A/B of the volume A in a charged state to the volume B in a discharged state is 1.2 or more. The lithium ion secondary battery has high capacity, high power, long life, and improved safety. In particular, heat generation due to an internal short-circuit is significantly suppressed in a nail penetration test.

Abstract: A cylindrical lithium secondary battery that is resistant to breakage of the porous heat-resistant layer and therefore excellent in both safety and battery characteristics. The cylindrical lithium secondary battery includes: a battery can having a bottom, a side wall, and an open top; an electrode assembly; a non-aqueous electrolyte; and a sealing plate covering the open top of the battery can that accommodates the electrode assembly and the electrolyte. The electrode assembly includes a strip-like positive electrode and a strip-like negative electrode that are wound together with a porous heat-resistant layer and a separator interposed between the positive and negative electrodes. The thickness A of the porous heat-resistant layer and the thickness B of the side wall of the battery can satisfy the relation: 0.005?A/B?0.1.

Abstract: A non-aqueous electrolytic secondary battery which includes a heat-resistant layer formed by a porous protective film or the like having a resin binder and an inorganic oxide filler between its negative electrode and a positive electrode has such a characteristic that the higher the battery's temperature becomes, the smaller its internal resistance value becomes. In a CC-CV charging method as a general method for charging a secondary battery, using such a characteristic that the internal resistance value of the non-aqueous electrolytic secondary battery lowers as the battery's temperature rises, a VC-charge range where a charge is given using an optimum charging-current value at a maximum level up to which the battery's temperature does not reach an excessive temperature even if a charging current flows is provided within a CC-charge range.

Abstract: A non-aqueous electrolyte secondary battery comprising a negative electrode having a current collector provided with convex portions and concave portions on both surfaces, a first columnar body formed in a tilting orientation on the convex portion on one of the surfaces of the current collector, and a second columnar body formed in a tilting orientation on the convex portion on the other surface, a positive electrode having a positive electrode current collector provided with a positive electrode mixture layer containing a positive electrode active material capable of reversibly inserting and extracting lithium ions on both surfaces, and a separator interposed between the positive electrode and the negative electrode in a confronting manner, wherein the first columnar body and the second columnar body on the negative electrode are tilted to an orthogonal direction of a winding direction of the current collector.

Abstract: A non-aqueous electrolyte secondary battery comprising at least a negative electrode having a current collector provided thereon with convex portions and columnar bodies formed on the convex portions, each of the columnar bodies comprising n stages (where n?2) of overlaid columnar body portions alternately tilted to different orientations along a longitudinal direction of the current collector, a positive electrode having a positive electrode current collector provided on both surfaces thereof with a positive electrode mixture layer containing a positive electrode active material capable of inserting and extracting lithium ions reversibly, and a separator interposed between the positive electrode and the negative electrode in a confronting manner, wherein tip portions of the columnar body portions at the uppermost stage of the columnar bodies on the negative electrode are tilted toward a trailing end of winding direction.

Abstract: The invention relates to a method for evaluating the safety of a battery under an internal short-circuit condition. The battery includes an electrode assembly comprising a wound laminate of a positive electrode plate, a negative electrode plate, and a separator interposed between the positive and negative electrode plates. The positive electrode plate includes a positive electrode current collector and a positive electrode active material layer on the positive electrode current collector, and the negative electrode plate includes a negative electrode current collector and a negative electrode active material layer on the negative electrode current collector. The battery further includes an electrolyte and a casing for housing the electrode assembly and the electrolyte.

Abstract: An evaluation method for evaluating safety of a battery having an electrode group including a positive electrode plate, a negative electrode plate and a separator inserted between said electrode plates. The method includes the steps of charging the battery to a predetermined voltage; incorporating conductive foreign matter into the charged battery such that the conductive foreign matter is in contact with the positive electrode plate, and not in contact with the negative electrode plate; immersing said battery into which the conductive foreign matter has been incorporated in an electrolyte to dissolve and deposit the conductive foreign matter, thereby causing an internal short circuit to occur in the battery; and evaluating a thermal behavior of the battery in which the internal short circuit has occurred, and outputting results of the evaluation as safety indices.

Abstract: The present invention relates to an internal short circuit evaluation method for a battery including an electrode group including a positive electrode plate, a negative electrode plate and a separator disposed between the positive electrode plate and the negative electrode plate, and an outer jacket covering the electrode group, the method including the steps of: (I) processing the electrode group to a predetermined position of the electrode group, from the outside of the electrode group toward the inside thereof; and (II) causing a short circuit between a portion of the electrode plate and a portion of the negative electrode plate of the electrode group that are located inside from the predetermined position, and measuring battery information that is changed by the short circuit, and an evaluation apparatus used for the above-described method.

Abstract: A method for evaluating the safety of a battery under an internal short-circuit condition. The method for evaluating an internal short-circuit of a battery is characterized in that a short-circuit can be caused at a desired location inside the battery. According to the evaluation method of the invention, the evaluation result is not affected by the constitution of the outermost part of the battery unlike nail penetration tests which are conventional evaluation methods. Also, unlike crush tests which are conventional evaluation methods, the locations of short-circuits do not vary among tests and the safety under an internal short-circuit condition can be evaluated accurately.

Abstract: A prismatic lithium secondary battery includes: a prismatic battery can having a bottom, a side wall, and an open top; an electrode assembly; a non-aqueous electrolyte; and a sealing plate covering the open top of the battery can that accommodates the electrode assembly and the non-aqueous electrolyte. The electrode assembly includes: a positive electrode; a negative electrode; and a porous heat-resistant layer and a separator that are interposed between the positive and negative electrodes. The side wall of the battery can has two rectangular main flat portions that are opposed to each other, and the thickness A of the porous heat-resistant layer and the thickness B of each of the main flat portions of the side wall satisfy the relation: 0.003?A/B?0.05.

Abstract: A separator for a lithium secondary battery includes a high molecular porous film with a shut-down function and a heat-resistant porous layer integrally formed on each side of the high molecular porous film. The heat-resistant porous layers contain a heat-resistant high-molecular material and a ceramic filler. By using the separator, the occurrence of a short-circuit due to the melting and shrinkage of the high molecular porous film is prevented. Also, in the event of a short-circuit and the generation of heat higher than the melting point of the material of the high molecular porous film, the expansion of the short-circuit is prevented, so that the safety of the lithium secondary battery is improved.

Abstract: Lubricating oil supply holes are drilled into a first member that is fitted to a plurality of first annular plates by a spline. Of splines to which each lubricating oil supply hole corresponds, lubricating oil grooves provided in the plurality of first annular plates do not overlap the splines on at least one of the front and rear surfaces of the first annular plates, and therefore lubricating oil flowing out of the lubricating oil supply holes is dispersed in a circumferential direction and flows from the inner periphery to the outer periphery of the first annular plates, rather than gathering in each lubricating oil groove and flowing in an outer peripheral direction. As a result, a force generated by an axial lubricating oil flow, which acts in a direction for causing the second annular plates to contact friction materials on the first annular plates, is suppressed, leading to a reduction in drag torque.

Abstract: A separator includes a porous sheet, a heat-resistant porous layer, and a metal lithium layer. The heat-resistant porous layer is provided on one of surfaces of the porous sheet. The metal lithium layer is provided on the surface of the heat-resistant porous layer. The separator is disposed between a negative electrode that includes an active material capable of reversibly storing and emitting lithium ions and having a theoretical capacity density of 400 mAh/g or higher, and a positive electrode capable of reversibly storing and emitting lithium ions, so that the metal lithium layer faces the negative electrode.

Abstract: A lithium secondary battery having enhanced safety, which includes an electrode group, a non-aqueous electrolyte and a battery can for housing them. The electrode group includes: a positive electrode having a strip-shaped positive electrode current collector and a material mixture layer carried thereon; a negative electrode having a strip-shaped negative electrode current collector and a material mixture layer carried thereon; a separator; and a porous heat resistant layer. The positive and negative electrodes are spirally wound with the separator and the porous heat resistant layer interposed therebetween. An outermost surface of the electrode group includes an exposed portion of either of the positive and negative electrode current collectors. The exposed portion faces an inner surface of the battery can with the separator interposed therebetween, and has opposite polarity to that of the battery can.

Abstract: A lithium ion secondary battery includes a positive electrode, a negative electrode, a non-aqueous electrolyte, and a separator interposed between the positive electrode and the negative electrode. The separator includes a polyolefin layer and an oxidation-resistant layer. The oxidation-resistant layer includes an oxidation-resistant polymer. A main chain of the oxidation-resistant polymer does not include a —CH2— group and a —CH(CH3)— group. The oxidation-resistant layer faces the positive electrode.