Sumitomo Chemical Company, Limited

Yoshihiro Kawakami

Yuichiro Imanari

Ryoji Kanno

Kenji Nakane

Hiroshi Ogawa

Takashi Yoshida

Satoshi Shimano

Yasunori Nishida

Hiroshi Inukai

Reiko Sasaki

Hiroshi Hamamatsu

Yoshiaki Honda

Ryuji Matsushita

Kazuyuki Tanino

Makoto Yoshioka

The present invention provides a lithium composite metal oxide containing Li and at least one transition metal element, wherein at least one lithium composite metal oxide particle constituting the lithium composite metal oxide has both hexagonal and monoclinic crystal structures. Further, the present invention also provides a lithium composite metal oxide containing Li, Ni and M (where, M represents one or more kinds of transition metal elements selected from the group consisting of Mn, Co and Fe), having a diffraction peak (diffraction peak A) at an angle 2&#x3b8; in a range from 20&#xb0; to 23&#xb0; in a powder X-ray diffraction pattern of a lithium composite metal oxide which is obtained by powder X-ray diffraction measurement made in the condition that CuK&#x3b1; is used as a radiation source and the measurement range of diffraction angle 2&#x3b8; is in a range from 10&#xb0; to 90&#xb0;.

Lithium composite metal oxide and nonaqueous electrolyte secondary battery

A method for producing a lithium mixed metal oxide, which includes mixing a lithium compound, metallic Ni or a compound thereof, and one or more transition metals selected from the group consisting of Mn, Co, Ti, Cr and Fe or a compound thereof; and calcining the obtained raw material mixture under an atmosphere of the concentration of carbon dioxide of from 1% by volume to 15% by volume at 630&#xb0; C. or higher.

Method for manufacturing a lithium complex metal oxide

To provide a lithium manganese composite oxide capable of improving the initial discharge capacity of secondary batteries by removing more Li ions than the conventional lithium manganese composite oxide does when used in the positive electrode used for secondary batteries. A lithium manganese composite oxide having a LiMnOtype crystal structure, wherein a part of Li and/or Mn in a lithium manganese oxide represented by a formula LiMnOis substituted by one or more doping elements M selected from the group consisting of Ti, Zr, Hf, V, Nb, Ta, Si, Ge, Sn, P, Sb and Bi. The above-described lithium manganese composite oxide, wherein the doping elements are P and/or Si. A positive electrode used for nonaqueous electrolyte secondary batteries, comprising the above-described lithium manganese composite oxide. A nonaqueous electrolyte secondary battery comprising the above-described positive electrode used for nonaqueous electrolyte secondary batteries.

Lithium manganese composite oxide

A lithium mixed metal oxide containing Li, Mn and M (M represents at least one metal element, and is free from Li or Mn), and having a peak around 1.5 &#x212b; (peak A), a peak around 2.5 &#x212b; (peak B), and the value of I/Iis not less than 0.15 and not more than 0.9 in a radial distribution function obtained by subjecting an extended X-ray absorption fine structure (EXAFS) spectrum at K absorption edge of Mn in the oxide to the Fourier transformation, wherein Iis the intensity of peak A and Iis the intensity of peak B.

Lithium mixed metal oxide

The positive electrode active material powder of the present invention is a positive electrode active material powder, including primary particles and aggregated particles of primary particles, wherein an average particle diameter of primary particles and aggregated particles of primary particles in the powder is 0.1 &#x3bc;m or more and 3 &#x3bc;m or less on a volume basis, the percentage of [volumetric sum of particles having a particle diameter of 5 &#x3bc;m or more]/[volumetric sum of entire particles] is 10% or less, and a BET specific surface area of the powder is more than 2 m/g and 7 m/g or less. When this positive electrode active material powder is used for a nonaqueous electrolyte secondary battery, it becomes possible to exhibit a high discharge capacity and also exhibit a high output at a high current rate.

Positive electrode active material powder

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.

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Ehime, Japan

Yoshihiro Kawakami