Sumitomo Chemical Company, Limited

Panasonic Corporation

Yasunori Nishida

Kenji Nakane

Tomoari Satoh

Yasuo Shinohara

Kenichiro Kami

Hiroyuki Sato

Mikinari Shimada

Shinji Kasamatsu

Hiroshi Ogawa

Taketsugu Yamamoto

Masahide Mohri

Hirohiko Hasegawa

Yoshihiro Kawakami

Hitoshi Miura

Kazuyuki Tanino

Takeshi Miyai

Chikashi Akamatsu

Provided is a laminated porous film suitable as a non-aqueous electrolyte secondary battery separator, which includes a heat resistant layer excellent in morphological stability at a high temperature and ion permeability and more resistant to fall-off of a filler. A laminated porous film in which a heat resistant layer including a binder resin and a filler and a base porous film including a polyolefin as a principal component are laminated, wherein the filler included in the heat resistant layer substantially consists of an inorganic filler (a) having a primary particle diameter of 0.2 to 1 &#x3bc;m and an inorganic filler (b) having a primary particle diameter of 0.01 to 0.1 &#x3bc;m, and the particle diameter of secondary aggregates of the inorganic filler (b) is not more than 2 times the primary particle diameter of the inorganic filler (a) in the heat resistant layer.

Laminated porous film, method for producing same, non-aqueous electrolyte secondary battery separator, laminated electrode sheet, and non-aqueous electrolyte secondary battery

A separator for use in a non-aqueous electrolyte secondary battery including a first porous layer (layer A) having a shutdown function which becomes substantially a non-porous layer at a high temperature, and a second porous layer (layer B) including an aramid resin and an inorganic material, wherein a ratio (T/T) of a thickness (T) of the layer A relative to a thickness (T) of the layer B is 2.5 or more and 13 or less.

Separator for use in non-aqueous electrolyte secondary battery and non-aqueous electrolyte secondary battery

Provided is a porous film comprising a heat-resistant resin and two or more fillers, wherein a value of D/Dis 0.15 or less where among values each obtained by measuring the average particle diameter of particles that constitute one of the two or more fillers, the largest value is let be Dand the second largest value is let be D.

Porous film

Provided is a separator made of a laminated porous film in which a heat-resistant layer that comprises a heat-resistant resin and a shut-down layer that comprises a thermoplastic resin are laminated, wherein the heat-resistant layer further comprises two or more fillers, and the value of D/Dis 0.15 or less where among values each obtained by measuring the average particle diameter of particles that constitute one of the two or more fillers, the largest value is let be Dand the second largest value is let be D.

Separator

Provided is an active material for a non-aqueous secondary battery having improved safety while maintaining the capacity and the cycle characteristic, a process for producing the same, and a non-aqueous secondary battery using the same. The active material can be doped/undoped with an alkali metal ion; the active material is a compound particle comprising three or more of constituting elements, and contains an element A selected from Li, Na, K, Mg, Ca, Sr, Ba, B, Al, Ga, In, Si, Zr, Sn, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Ag and Zn as one of the constituting elements; the particle has a region where the concentration of element A is decreasing continuously in the direction of from the particle surface to the particle core; and the ratio (d/D) of the mean width (d) of this region towards the depth direction to the mean radius (D) of the particle is 0.001<d/D<0.5.

Active material for non-aqueous secondary battery, and non-aqueous secondary battery using the same

Provided is a lithium secondary battery of a high energy density using a cathode active material having an excellent cycle characteristic in charging/discharging at a high capacity and a small irreversible capacity. The lithium secondary battery comprising: a cathode including a material that can be doped/undoped with lithium ions as an active material; an anode including a lithium metal, a lithium alloy, or a material that can be doped/undoped with lithium ions as an active material; and a liquid or solid electrolyte, wherein lithiated nickel dioxide containing tin is used as the cathode active material, and said lithiated nickel dioxide has a peak near 2&thgr;&equals;34.4&deg; and does not have a peak near 2&thgr;&equals;22.5&deg; in the X-ray diffraction pattern by CuK&agr; rays, or the intensity ratio of the peak near 2&thgr;&equals;22.5&deg; to the peak near 2&thgr;&equals;34.4&deg; is 1.2 or less.

Lithium secondary battery and cathode active material for use in lithium secondary battery

A cathode for a lithium secondary battery wherein the surface of the cathode of which a composition containing a cathode active material, a conductive substance and a binder is supported on a current collector, is coated with at least one ion-permeable resin selected from resins having a temperature of deflection under load (measured at 18.6 kg/cm,load according to JIS K 7207) not lower than 100 &deg; C., provide a lithium secondary battery with high energy density having improved safety.

Cathode for lithium secondary battery

A lithium secundary battery cathode composition comprising a cathode active material, a conductive substance and a binder, wherein the binder comprises a fluororesin and a polyolefin resin, and the amount of the fluororesin in the composition is 1 to 10% by weight and the amount of the polyolefin resin in the composition is 0.1 to 2% by weight. The cathode using the cathode composition of the present invention has an excellent binding property with a current collector, and the lithium secondary battery of the present invention has a high energy density and improved safety against an external heating, and the industrial value is very high.

The invention provides a cathode for a lithium secondary battery including lithiated nickel dioxide with a large discharge capacity as an active material and having a high density so that a larger amount of the active material can be charged in a battery container with a limited volume, a production method for the same and a lithium secondary battery utilizing the cathode. The cathode for a lithium secondary battery includes lithiated nickel dioxide as an active material, and the lithiated nickel dioxide is produced by firing a mixture of a lithium compound and a nickel compound at a temperature ranging between 350.degree. C. and 800.degree. C. The supernatant obtained by dispersing 5 g of the lithiated nickel dioxide in 100 cm.sup.3 of water in a glass vessel for 5 minutes and allowing the resultant solution to stand for 30 seconds has pH of 12.00 or less. The production method includes the steps of obtaining the lithiated nickel dioxide as above and treating or milling the lithiated nickel dioxide in an atmosphere including carbon dioxide.

Cathode for lithium secondary battery and production method for the same

The invention provides a cathode material for lithium secondary battery containing lithiated nickel dioxide having excellent charge/discharge characteristics and a process for producing the lithiated nickel dioxide, and a lithium secondary battery. That is, the cathode material for lithium secondary battery contains lithiated nickel dioxide having .alpha.-NaFeO.sub.2 structure and shows a coulomb efficiency of 80% or higher at the first charging and discharging, and the process for producing lithiated nickel dioxide comprises dispersing a nickel compound in a lithium nitrate solution, then evaporating the solvent to obtain a mixture of lithium nitrate and the nickel compound and firing the mixture in an atmosphere containing oxygen.

Cathode material for lithium secondary battery and method for producing

The invention provides a cathode material for lithium secondary battery containing lithiated nickel dioxide having excellent charge/discharge characteristics and a process for producing the lithiated nickel dioxide, and a lithium secondary battery. That is, the cathode material for lithium secondary battery contains lithiated nickel dioxide having .alpha.-NaFeO.sub.2 structure and shows a coulomb efficiency of 85% or higher at the first charging and discharging, and the process for producing lithiated nickel dioxide comprises dispersing a nickel compound in a lithium nitrate solution, then evaporating the solvent to obtain a mixture of lithium nitrate and the nickel compound and firing the mixture in an atmosphere containing oxygen.

A lithium secondary battery that includes a cathode containing, as an active material, a material that can be doped/undoped with lithium ions; an anode containing, as an active material, a lithium metal, a lithium alloy or a material that can be doped/undoped with lithium ions; and a liquid or solid electrolyte. In this lithium secondary battery, the active material used in the cathode is lithiated nickel dioxide containing gallium. As a result, the lithium secondary battery attains excellent cycle and overcharge resistance characteristics and has a high energy density.

Lithium secondary battery having a cathode containing galliam

A sintered body where alumina is dispersed in a zirconia matrix in which yttria has been doped to form a solid solution can be obtained by compacting a mixed powder comprising zirconia or yttria-stabilized zirconia and yttrium-aluminum complex oxide and sintering the resulting compacted body. This sintered body comprises a fine zirconia matrix in which fine alumina particles are dispersed to strengthen it and is excellent in flexural strength and fracture toughness and has a practically effective oxygen ionic conductivity.

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Tsukuba, Japan

Yasunori Nishida