Sharp Kabushiki Kaisha Corporation

Koji Ohira

Motoaki Nishijima

Isao Tanaka

Koji Fujita

Shunsuke Murai

Toshitsugu Sueki

Yukinori Koyama

Katsuhisa Tanaka

Shogo Esaki

Shougo Esaki

Yuichi Kamimura

Tomohisa Yoshie

A cathode active material of the present invention is a cathode active material having a composition represented by General Formula (1) below,LiFeMPSiO&#x2003;&#x2003;(1),

Cathode active material, cathode and nonaqueous secondary battery

A positive electrode active substance including a lithium-containing metal oxide represented by the following general formula (1):LiFeMPSiO&#x2003;&#x2003;(1)

Positive electrode active substance containing lithium-containing metal oxide

A cathode active material of the present invention is a cathode active material having a composition represented by General Formula (1) below,LiFeMPSiO&#x2003;&#x2003;(1), where: an average valence of Fe is +2 or more; M is an element having a valence of +2 or more and is at least one type of element selected from the group consisting of Zr, Sn, Y, and Al; the valence of M is different from the average valence of Fe; 0&#x3c;x&#x2266;0.5; and y=x&#xd7;({valence of M}&#x2212;2)+(1&#x2212;x)&#xd7;({average valence of Fe}&#x2212;2). This provides a cathode active material that not only excels in terms of safety and cost but also can provide a long-life battery.

Provided is a cathode active material which is superior in safety and cost and makes it possible to provide a nonaqueous secondary battery having a long life. The cathode active material has a composition represented by the following formula (1):LiMnMPAlO&#x2003;&#x2003;(1) (wherein M is at least one selected from the group consisting of Ti, V, Zr, Sn and Y, x is in a range of 0&#x3c;x&#x2266;0.5, and y is in a range of 0&#x3c;y&#x2266;0.25).

Cathode active material, cathode, and nonaqueous secondary battery

A cathodic active material for a nonaqueous electrolyte secondary battery according to the invention includes a lithium-containing transition metal phosphate containing Li and a transition metal. A transition metal site and P site of the lithium-containing transition metal phosphate are replaced by elements other than elements contained in the lithium-containing transition metal phosphate, and the quantity of P site is excessive with respect to a stoichiometric proportion of the lithium-containing transition metal phosphate. With this cathodic active material, a high-power and high-capacity secondary battery which is superior in safety and cost and has superior rate performance can be provided.

Cathodic active material for nonaqueous electrolyte secondary battery, cathode for nonaqueous electrolyte secondary battery, and nonaqueous electrolyte secondary battery

Provided is a positive electrode active material giving nonaqueous-electrolyte secondary batteries superior in cycle characteristics. The positive electrode active material according to the present invention includes a lithium-containing composite metal oxide having the composition represented by the following General Formula (1):LiFeMPSiO&#x2003;&#x2003;(1)(wherein M is at least one metal element selected from Zr, Sn, Y, and Al, 0.05&#x3c;x&#x3c;1, and 0.05&#x3c;y&#x3c;1), characterized in that: the positive electrode active material is in the single crystalline phase of the lithium-containing composite oxide represented by General Formula (1) when 1&#x3e;z&#x3e;0.9 to 0.75 or 0.25 to 0.1&#x3e;z&#x3e;0;the positive electrode active material has two crystalline phases of the lithium-containing composite oxides represented by the following General Formulae (2) and (3) when 0.9 to 0.75&#x3e;z&#x3e;0.25 to 0.1:LiFeMPSiO&#x2003;&#x2003;(2)(wherein 0.75 to 0.9&#x2266;a&#x2266;1.00, 0.05&#x3c;x&#x3c;1, and 0.05&#x3c;y&#x3c;1); andLiFeMPSiO&#x2003;&#x2003;(3)(wherein, 0&#x2266;b&#x2266;0.1 to 0.25+x, 0.05&#x3c;x&#x3c;1, and 0.05&#x3c;y&#x3c;1), andwhen the product of the lengths of the b and c axes of the unit cell of the lithium-containing composite oxide of General Formula (2) is designated as bc1 and the product of the lengths of the b and c axes of the unit cell of the lithium-containing composite oxide of General Formula (3) as bc2, &#x3b1;, which is defined by equation &#x3b1;=(bc2)/(bc1), is 0.99&#x3c;&#x3b1;&#x3c;1.01.

Positive electrode active material, positive electrode, and nonaqueous-electrolyte secondary battery

A cathode active material comprising a composition represented by the following general formula (1):LiM1M2M3PSiO&#x2003;&#x2003;(1)wherein M1 is at least one kind of element selected from the group of Mn, Fe, Co and Ni; M2 is any one kind of element selected from the group of Ti, V and Nb; M3 is at least one kind of element selected from the group of Zr, Sn, Y and Al; 'a' satisfies 0&#x3c;a&#x2266;1; 'x' satisfies 0&#x3c;x&#x2266;2; &#x201c;y&#x201d; satisfies 0&#x3c;y&#x3c;1; &#x201c;z&#x201d; satisfies 0&#x2266;z&#x3c;1; &#x201c;m&#x201d; satisfies 0&#x2266;m&#x3c;1; and &#x201c;n&#x201d; satisfies 0&#x3c;n&#x2266;1.

Cathode active material, cathode electrode, and non-aqueous secondary battery

A cathode active material comprising a composition represented by the following general formula (1):LiM1M2M3PSiO&#x2003;&#x2003;(1)wherein M1 is at least one kind of element selected from the group of Mn, Fe, Co and Ni; M2 is any one kind of element selected from the group of Zr, Sn, Y and Al; M3 is at least one kind of element selected from the group of Zr, Sn, Y, Al, Ti, V and Nb and different from M2; 'a' satisfies 0&#x3c;a&#x2266;1; 'x' satisfies 0&#x3c;x&#x2266;2; &#x201c;y&#x201d; satisfies 0&#x3c;y&#x3c;1; &#x201c;z&#x201d; satisfies 0&#x3c;z&#x3c;1; &#x201c;m&#x201d; satisfies 0&#x2266;m&#x3c;1; and &#x201c;n&#x201d; satisfies 0&#x3c;n&#x2266;1.

Cathode active material, cathode electrode and non-aqueous secondary battery

A method of producing a positive electrode active material, comprising the steps of:

Positive electrode active material, production method thereof and its use

A cathode active material having a composition represented by the following formula (1)LiMnMPSiO&#x2003;&#x2003;(1)

Cathode active material, cathode and non-aqueous secondary battery

The present invention provides a method for producing a lithium-containing composite oxide represented by general formula (1) below, the method at least including a step of preparing a solution by dissolving a lithium source, an element M source, a phosphorus source, and an element X source that serve as source materials in a solvent, the phosphorus source being added after at least the element M source is dissolved; a step of gelating the resulting solution; and a step of calcining the resulting gel:LiMPXO&#x2003;&#x2003;(1)(where M represents at least one element selected from the group consisting of Fe, Ni, Mn, Zr, Sn, Al, and Y; X represents at least one element selected from the group consisting of Si and Al; and 0&#x3c;x&#x2266;2, 0.8&#x2266;y&#x2266;1.2, 0&#x2266;z&#x2266;1). According to the present invention, a positive electrode active material for lithium secondary batteries that offers high safety and high cost efficiency and are capable of extending battery life can be provided.

Method for producing lithium-containing composite oxide

A positive electrode active substance comprising a lithium-containing metal oxide

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Osaka, Japan

Koji Ohira