Sanyo Electric Co., Ltd.

Katsutoshi Takeda

Masahisa Fujimoto

Hideyuki Koga

Motoharu Saito

Hiroshi Sawada

Yoshio Kato

Shigeki Matsuta

Shingo Tode

Masanori Maekawa

Toshihiro Kinoshita

Masao Isomura

A method for producing a non-aqueous electrolyte secondary cell by preparing a positive electrode by applying a positive electrode mixture onto a positive electrode core material, the mixture containing a positive electrode active material mainly made of a lithium nickel composite oxide and a binding agent containing polyvinylidene fluoride; measuring the amount of carbon dioxide gas generated when a layer of the positive electrode mixture is removed out of the positive electrode and the layer is heated to 200&#xb0; C. or higher and 400&#xb0; C. or lower in an inactive gas atmosphere; selecting a positive electrode satisfying the following formulas:(0.27&#x2212;51)/1000000(200&#x2266;&#x3c;400)&#x2003;&#x2003;formula 157/1000000(400&#x2266;&#x2266;1500)&#x2003;&#x2003;formula 2where x is a heating temperature (&#xb0; C.) and y is the amount of carbon dioxide gas (mole/g) per 1 g of the lithium nickel composite oxide measured; and preparing the non-aqueous electrolyte secondary cell by using the positive electrode selected.

Method for producing positive electrode for non-aqueous electrolyte secondary cell and method for producing non-aqueous electrolyte secondary cell

A non-aqueous electrolyte secondary battery having a negative electrode, a non-aqueous electrolyte, and a positive electrode having a positive electrode active material comprising sodium oxide, is characterized in that the sodium oxide contains lithium, and the molar amount of the lithium is less than the molar amount of the sodium.

Non-aqueous electrolyte secondary battery and method of manufacturing the same

A positive electrode active material is made of sodium containing oxide. The sodium containing oxide contains NaLiMOthat belongs to a space group P6/mmc of a hexagonal system, where the M includes at least one of manganese (Mn) and cobalt (Co). In the NaLiMO, the composition ratio A of sodium (Na) is not less than 0.5 and not more than 1.1, the composition ratio B of lithium (Li) is larger than 0 and not more than 0.3, and the &#x3b1; is not less than 0 and not more than 0.3.

Nonaqueous electrolyte secondary battery

A method for producing a non-aqueous electrolyte secondary cell by preparing a positive electrode by applying a positive electrode mixture onto a positive electrode core material, the mixture containing a positive electrode active material mainly made of a lithium nickel composite oxide and a binding agent containing polyvinylidene fluoride; measuring the amount of carbon dioxide gas generated when a layer of the positive electrode mixture is removed out of the positive electrode and the layer is heated to 200&#xb0; C. or higher and 400&#xb0; C. or lower in an inactive gas atmosphere; selecting a positive electrode satisfying the following formulas:&#x3c;(1.31&#x2212;258)/1000000(200&#x2266;&#x3c;300)&#x2003;&#x2003;formula 3&#x3c;1.20&#x2212;225/1000000(300&#x2266;&#x2266;400)&#x2003;&#x2003;formula 4where x is a heating temperature (&#xb0; C.) and y is the amount of carbon dioxide gas (mole/g) per 1 g of the lithium nickel composite oxide measured; and preparing the non-aqueous electrolyte secondary cell by using the positive electrode selected.

A method of producing a non-aqueous electrolyte secondary battery having a negative electrode, a non-aqueous electrolyte, and a positive electrode having a positive electrode active material comprising sodium oxide, characterized in that: the sodium oxide contains lithium; and the molar amount of the lithium is less than the molar amount of the sodium.

A positive electrode active material quality judgment method that can easily and accurately judge the quality of a positive electrode active material used in a non-aqueous electrolyte secondary cell without having to complete the positive electrode. The positive electrode active material quality judgment method includes: heating a positive electrode active material mainly made of a lithium nickel composite oxide to a temperature x (&#xb0; C.) of 200&#xb0; C. or higher and 400&#xb0; C. or lower; measuring the amount of carbon dioxide gas generated from the heating; and the positive electrode active material as a suitable positive electrode active material when the positive electrode active material satisfies formulas 3 and 4:&#x3c;(1.31&#x2212;258)/1000000(200&#x2266;&#x3c;300)&#x2003;&#x2003;formula 3&#x3c;1.20&#x2212;225/1000000(300&#x2266;&#x2266;400)&#x2003;&#x2003;formula 4where x is the heating temperature x (&#xb0; C.) and y is the amount of carbon dioxide gas (mole/g) generated per 1 g of the positive electrode active material in the heating to the heating temperature x (&#xb0; C.).

Method for judging quality of lithium nickel composite oxide and positive electrode using lithium nickel composite oxide

A mixed positive electrode active material is used. The mixed positive electrode active material is obtained by mixing a layered oxide whose initial charge-discharge efficiency when lithium metal is used for a counter electrode is less than 100% (hereinafter referred to as a first layered oxide) and a layered oxide whose initial charge-discharge efficiency is 100% or more (hereinafter referred to as a second layered oxide). Examples of the first layered oxide include LiMnCoNiO. A sodium oxide such as LiNaMnCoNiOother than a layered compound from which lithium is previously extracted by acid treatment or the like can be used as the second layered oxide whose initial charge-discharge efficiency is 100% or more. A layered oxide obtained by replacing (ion exchange) sodium in the foregoing LiNaMnCoNiOwith lithium can be also used as the second layered oxide.

Nonaqueous electrolyte secondary battery and method of manufacturing the same

A positive electrode active material is formed of a lithium containing layered oxide. The lithium containing layered oxide contains either or both of LiNaMnCoOthat belongs to a space group P6mc or LiNaMnCoOthat belongs to a space group Cmca. The lithium containing layered oxide contains the LiNaMnCoOas a solid solution, a mixture or both of them. In the LiNaMnCoO, 0.5&#x2266;A&#x2266;1.2, 0&#x3c;B&#x2266;0.01, 0.40&#x2266;x&#x2266;0.55, 0.40&#x2266;y&#x2266;0.55, 0.80&#x2266;x+y&#x2266;1.10 and 0&#x2266;&#x3b1;&#x2266;0.3.

Nonaqueous electrolyte secondary battery and method of forming positive electrode

A positive electrode active material including lithium (Li), nickel (Ni), manganese (Mn) and a transition metal that can be in the hexavalent state is used. As the transition metal that can be in the hexavalent state, for example, one or both of tungsten (W) and molybdenum (Mo) can be used. As the positive electrode active material including a plurality of materials as mentioned above, LiNiMnOcan be used. As a negative electrode, a carbon material or a silicon material capable of storing and releasing lithium ions can be used.

Non-aqueous electrolyte secondary battery

LiAMOobtained by replacing lithium in LiMOhaving a layered structure by an alkali metal having ion radius larger than that of lithium is used as a positive electrode active material. In this LiAMO, x satisfies the relation 0&#x3c;x&#x2266;O.5, the above-mentioned A indicates the alkali metal having the ion radius larger than that of lithium (Li) (for example, sodium (Na) or potassium (K)) and M indicates a transition metal that can be tetravalent. Examples of the transition metal that can be tetravalent indicated by the above-mentioned M include manganese (Mn), molybdenum (Mo), titanium (Ti), platinum (Pt), iridium (Ir), ruthenium (Ru) and the like.

A ZnO buffer layer having an electric conductivity of 1&#xd7;10S/cm or lower or alternatively a ZnO buffer layer having a diffraction peak of a crystal face other than (002) and (004) in X-ray diffraction is formed on a substrate by sputtering. A ZnO semiconductor layer is formed on the ZnO buffer layer. The ZnO semiconductor layer is formed under the condition that the flow rate ratio of an oxygen gas in a sputtering gas is lower than that in the formation of the ZnO buffer layer.

Method for forming ZnO film, method for forming ZnO semiconductor layer, method for fabricating semiconductor device, and semiconductor device

Two types of solar cell modules having an equal output voltage and different sizes are used, and a plurality of solar cell modules of these two types are installed so that they are connected in parallel. The size of a solar cell module having two solar cell sub-modules is two times larger than the size of a solar cell module including one solar cell sub-module. By connecting two power generating regions of each of the solar cell sub-modules of the former solar cell module in parallel, connecting adjacent two solar cell sub-modules in series and connecting two power generating regions of the solar cell sub-module of the latter solar cell module in series, an equal output voltage is obtained from both of the solar cell modules.

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Moriguchi, Japan

Katsutoshi Takeda