Sharp Kabushiki Kaisha Corporation

Toyota Jidosha Kabushiki Kaisha

Honda Motor Co., Ltd.

Kyoto University

Yukinori Koyama

Motoaki Nishijima

Isao Tanaka

Koji Fujita

Shunsuke Murai

Koji Ohira

Toshitsugu Sueki

Katsuhisa Tanaka

Shogo Esaki

Shougo Esaki

Zempachi Ogumi

Jun-ichi Yamaki

Toshiro Hirai

Ken-ichi Okazaki

Hideyuki Horino

A secondary battery in which the difference between the voltage at the time of discharging and the voltage at the time of charging is small, ensuring good energy efficiency, and the charge/discharge life is long. Therefore, in order to attain the above-described object, a secondary battery containing a positive electrode, a negative electrode, and an electrolytic solution, wherein at least one of the positive electrode and the negative electrode contains, as the active material, at least one selected from the group consisting of a metal ion-containing fluoride, a metal oxide, a metal sulfide, a metal nitride, and a metal phosphide; the electrolytic solution contains an anion receptor; and the anion receptor forms a salt or a complex with an anion contained in the active material, thereby enabling the active material to dissolve in the electrolytic solution.

Secondary battery

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

Positive electrode active material, production method thereof and its use

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

Growing community of inventors

Kyoto, Japan

Yukinori Koyama