Hitachi Maxell, Limited

Hitachi Maxell Energy, Ltd.

Kazunobu Matsumoto

Akira Kawakami

Masayuki Yamada

Hideaki Yumiba

Hiroshi Fukunaga

Fusaji Kita

Akira Inaba

Kazutaka Uchitomi

Naokage Tanaka

Hayato Higuchi

Koji Murakami

Keiichiro Uenae

Hiroki Ishikawa

Minako Iwasaki

Qiao Shi

Hiroyuki Toshiro

[Objectives] The present invention provides a non-aqueous secondary battery in which a material containing Si and O as constituent elements is used in a negative electrode. The present invention provides a non-aqueous secondary battery having good charge discharge cycle characteristics, and suppressing the battery swelling associated with the charge and the discharge. Also, the present invention relates to a negative electrode that can provide the non-aqueous secondary battery. [Solution] The negative electrode includes a negative electrode active material, including a composite of a material containing Si and O as constitution elements (atom ratio x of O to Si is 0.5&#x2266;x&#x2266;1.5) in combination with a carbon material, and graphite. The graphite has an average particle diameter dg (&#x3bc;m) of 4 to 20 &#x3bc;m. The material containing Si and O as constitution elements has an average particle diameter ds (&#x3bc;m) of 1 &#x3bc;m or more. The ratio ds/dg (i.e., ds to dg) is 0.05 to 1. The material containing Si and O as constitution elements has a crystallite diameter of 50 nm or less, the crystallite diameter is calculated from a half width at a (220) plane of Si obtained by an X-ray diffraction method, using Scherrer Formula. In 100 mass % of the composite of the material containing Si and O as constitution elements, and the carbon material, a ratio of the material containing Si and O as constitution elements is 70 to 95 mass %.

Negative electrode for non-aqueous secondary battery, and a non-aqueous secondary battery

A non-aqueous secondary battery of the present invention includes a positive electrode, a negative electrode and a non-aqueous electrolyte. The positive electrode includes a positive electrode material mixture layer containing a lithium-containing transition metal oxide. The negative electrode includes a negative electrode material mixture layer and a porous layer containing an insulating material unreactive with lithium formed thereon. The negative electrode material mixture layer includes a negative electrode material including a core and a carbon covering layer covering a surface of the core. The core includes a material containing silicon and oxygen at an atomic ratio x of the oxygen to the silicon of 0.5&#x2266;&#xd7;&#x2266;1.5. The material containing silicon and oxygen has a peak at least in a range of 1850 to 1860 eV in an X-ray absorption near edge structure spectrum at the K absorption edge of Si in a state in which discharge of the battery is finished.

Non-aqueous secondary battery and method for producing the same

A non-aqueous secondary cell comprising a wound structure, in which a positive electrode having a positive collector carrying positive active material on both sides at least at a part of the collector and a negative electrode having a negative collector carrying a negative active material on both sides at least at a part of the collector are wound with inserting a separator inbetween, and a cell can for holding said electrodes, in which the electrode, which faces the can, consists of either electrode material, the outer side of the positive collector at least in the outermost part of the positive electrode has no coating film containing a positive active material, said outer most part of the positive collector faces the negative electrode or the inner wall of the cell can through the separator, and a lead member which is welded to the negative collector does not directly face the positive electrode through the separator.

Non-aqueous secondary cell

Lithium secondary battery containing organic electrolyte, active

There is provided a lithium cell comprising a negative electrode made of lithium or a lithium containing material, an electrolytic solution based on an organic solvent, and a positive electrode active material which comprises a copper compound oxide and an atomic ratio of a number of lithium atoms (Li) which react with one molecule of the copper compound oxide during discharge of the lithium cell to a number of oxygen atoms (O) contained in one molecule of the copper compound oxide, which ratio is expressed as Li/O, is at least 1.

Lithium cell

Lithium cell with a cathode comprising a copper compound oxide

Growing community of inventors

Mishima-gun, Japan

Kazunobu Matsumoto