Toyota Jidosha Kabushiki Kaisha

Sumitomo Metal Mining Company, Ltd.

Hideyuki Saka

Keiichi Takahashi

Hideaki Fujita

Tatsuya Hashimoto

Yukihiro Okada

Kaoru Inoue

Yusuke Fukumoto

Hiroyuki Toya

Hideki Sano

Keisuke Ohara

Tetsutaro Hayashi

Shuhei Oda

Kouichi Toriyama

A non-aqueous secondary battery includes a positive electrode composite material layer. In a cross-section in a direction of thickness of the positive electrode composite material layer, the positive electrode composite material layer includes a first region including one end portion in a direction intersecting with the direction of thickness, a second region including the other end portion, and a third region lying between the first region and the second region. The first region is composed of a first composite material containing lithium iron phosphate and lithium nickel cobalt manganese composite oxide, and the second region is composed of a second composite material containing lithium iron phosphate and lithium nickel cobalt manganese composite oxide. The third region is composed of a third composite material containing lithium nickel cobalt manganese composite oxide.

Non-aqueous secondary battery

A battery assembly disclosed herein is a battery assembly before being subjected to initial charge. In the battery assembly, a positive electrode has a positive electrode mixture layer that contains a positive electrode active material and NMP, and an oxalate complex compound and FSOLi are contained in a nonaqueous electrolyte solution. In the battery assembly disclosed herein, a NMP content in the positive electrode mixture layer is 50 ppm to 1500 ppm, the DBP oil absorption of the positive electrode active material is 30 ml/100 g to 45 ml/100 g, and a FSOLi content in the nonaqueous electrolyte solution is 0.1 wt % to 1.0 wt %. With this, it is possible to prevent a reduction in input-output characteristics caused by formation of a film derived from NMP on the surface of the positive electrode active material, and hence it is possible to prevent an increase in facility cost and a reduction in manufacturing efficiency caused by adjustment of the content of NMP.

Battery assembly and method of manufacturing nonaqueous electrolyte secondary battery

A nonaqueous electrolyte secondary battery according to the present invention includes: an electrode body including a positive electrode including a positive-electrode active material layer; an external terminal connected to the electrode body; a nonaqueous electrolyte including a gas generant, and a current interrupt device. A content of the gas generant is at least 4 mass %. The positive-electrode active material layer includes, as a positive-electrode active material, a complex oxide containing at least zirconium (Zr) and calcium (Ca) as constituent elements. When a sum total of metal elements, except metal that becomes a charge carrier, in the complex oxide is 100 mol % in terms of a mole percentage, the complex oxide contains Zr from 0.1 mol % to 0.5 mol % inclusive and Ca from 0.1 mol % to 0.3 mol % inclusive.

Nonaqueous electrolyte secondary battery

A positive electrode active material for lithium secondary batteries disclosed herein comprises a lithium transition metal oxide of a layered structure, represented by formula LiNiCoMnCaMO(where &#x2212;0.05&#x2264;&#x3b1;&#x2264;0.2, x+y+z+&#x3b2;+&#x3b3;&#x2245;1, 0.3&#x2264;x&#x2264;&#x2264;0.7, 0.1&#x2264;y&#x2264;0.4, 0.1&#x2264;z&#x2264;0.4, 0.0002&#x2264;&#x3b2;&#x2264;0.0025, 0.0002&#x2264;&#x3b2;+&#x3b3;&#x2264;0.02, and in a case where &#x3b3;&#x3e;0, M is absent or represents one, two or more elements selected from the group consisting of Na, Mg, Al, Ti, V, Cr, Zr, Nb, Mo, Hf, Ta and W). The tap density of the positive electrode active material ranges from 1.8 to 2.5 g/cm.

Positive electrode active material, and lithium secondary battery using same

A nonaqueous electrolyte secondary battery () includes a positive electrode (), a negative electrode (), a separator (), a nonaqueous electrolytic solution, and a battery case (). The positive electrode includes a positive electrode current collector () and a positive electrode active material layer (). The separator includes a separator substrate () and a heat resistance layer (). The separator substrate has an opposite surface opposite the positive electrode active material layer. The heat resistance layer constitutes at least a part of the opposite surface and contains a heat-resistant filler and a binder. The positive electrode active material layer has an adjacent region (X). The heat resistance layer has an opposite region (Y) opposite at least an end portion of the adjacent region. The end portion of the adjacent region is adjacent to a positive electrode current collector exposure portion (). The opposite region contains at least a calcium salt of carboxymethyl cellulose.

Provided is a lithium ion secondary battery which has a low internal resistance in a low-SOC region and a sufficiently large amount of gas generated during overcharge. The lithium ion secondary battery disclosed herein includes an electrode body having a positive electrode and a negative electrode, and a nonaqueous electrolytic solution. The lithium ion secondary battery further includes a pressure-type safety mechanism. The nonaqueous electrolytic solution includes a gas generating agent. The positive electrode has a positive electrode active material layer including a positive electrode active material. The positive electrode active material includes a lithium transition metal composite oxide represented by LiNiCoMnOwherein a, b and c satisfy the following conditions: 0.35&#x2264;a&#x2264;0.45, 0.15&#x2264;b&#x2264;0.25, 0.35&#x2264;c&#x2264;0.45, and a+b+c=1, and a lithium transition metal composite oxide represented by LiNiCoMnOwherein x, y and z satisfy the following conditions: 0.35&#x2264;x&#x2264;0.45, 0.45&#x2264;y&#x2264;0.55, 0.05&#x2264;z&#x2264;0.15, and x+y+z=1, and the mass ratio of the oxides is 60:40 to 85:15.

Lithium ion secondary battery

A positive electrode mixture layer () includes a first layer () that has a main surface MS and a second layer () formed closer to the positive electrode current collector () side than the first layer (). A ratio of the volume of the first layer () to the volume of the positive electrode mixture layer () is 20 to 75 vol %. The first layer () contains lithium iron phosphate (LFP) () and lithium nickel cobalt manganese composite oxide (NCM) (). A ratio of the mass of the LFP () to the total mass of the LFP () and the NCM () in the first layer () is more than 0 and 80 mass % or less. The second layer () contains NCM (). A ratio of the mass of the LFP () to the total mass of the positive electrode active material in the positive electrode mixture layer () is 7.5 to 20 mass %. A maximum pore size of the first layer () is 0.50 to 0.70 &#x3bc;m.

Provided is a non-aqueous electrolyte secondary battery which exhibits excellent energy density and excellent input/output density (and especially output density in low SOC regions). This invention discloses a non-aqueous electrolyte secondary battery that includes a positive electrode, a negative electrode and a non-aqueous electrolyte. The positive electrode includes a positive electrode current collector and a positive electrode active material layers formed on the positive electrode current collector. The positive electrode active material layer has two regions that are demarcated in a surface direction of the positive electrode current collector, which are a first regioncontaining mainly a positive active material of lithium iron phosphate, and a second regioncontaining mainly a positive active material of a lithium-transition metal composite oxide.

Non-aqueous electrolyte secondary battery

Provided is a non-aqueous electrolyte secondary battery combining high battery performance in normal use and endurance against overcharge. The non-aqueous electrolyte secondary battery comprises a positive electrode, a negative electrode, and a non-aqueous electrolyte. The positive electrode comprises a positive electrode active material. Positive electrode active materialis formed of a particulate lithium composite oxidecomprising at least lithium, nickel, cobalt, manganese and tungsten; and a nickel oxide layerformed on the lithium composite oxide surface. With the non-lithium metals in lithium composite oxidebeing 100% by mole, tungsten accounts for 0.05% by mole or greater, but 2% by mole or less. With lithium composite oxidebeing 100 parts by mass, the nickel oxide content is 0.01 part by mass or greater, but 2 parts by mass or less.

Non-aqueous electrolyte secondary battery and positive electrode active material for use in same

A method of manufacturing a non-aqueous liquid electrolyte secondary battery is to manufacture a non-aqueous liquid electrolyte secondary battery including a positive electrode mixture layer containing a lithium-containing transition metal oxide as a positive electrode active material. The manufacturing method includes: mixing the positive electrode active material and an aromatic nitrile compound such that a mass ratio of the aromatic nitrile compound to the positive electrode active material is not less than 0.1% by mass and not more than 4% by mass, to prepare a mixture; mixing the mixture, a conductive material, a binder, and a solvent to prepare a granular body; and disposing the granular body on a surface of a positive electrode collector to form at least a part of the positive electrode mixture layer.

Method of manufacturing non-aqueous liquid electrolyte secondary battery

A non-aqueous electrolyte secondary battery includes a positive electrode composite material layer containing first positive electrode active material particles containing a lithium nickel composite oxide, second positive electrode active material particles containing lithium iron phosphate, and a conductive material. A ratio of the second positive electrode active material particles in a total mass of the first positive electrode active material particles and the second positive electrode active material particles is not lower than 5 mass % and not higher than 20 mass %. A standard deviation &#x3c3; representing distribution of an iron element satisfies a condition of 0.28&#x2266;&#x3c3;&#x2266;0.52 when distribution of the iron element is determined by conducting area analysis with an electron probe microanalyzer in a cross-section of the positive electrode composite material layer.

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Toyota, Japan

Hideyuki Saka