Sumitomo Metal Mining Company, Ltd.

Toyota Jidosha Kabushiki Kaisha

Denso Corporation

Shigeki Kubo

Manabu Yamada

Katsuya Kase

Satoru Suzuki

Hirofumi Iisaka

Ko Nozaki

Hiroshi Nakahira

Osamu Yamamoto

A method of manufacturing a non-aqueous electrolyte secondary battery is provided wherein the positive electrode is made from a lithium-metal composite oxide represented by the general formula Li(Ni, Co)MO(0.98&#x2266;x&#x2266;1.10, 0.05&#x2266;y&#x2266;0.4, 0.01&#x2266;z&#x2266;0.2, in which M represents at least one element selected from the group consisting of Al, Mg, Mn, Ti, Fe, Cu, Zn and Ga), and having an average particle diameter of 5 &#x3bc;m to 10 &#x3bc;m a C-amount of 0.14 wt % or less measured by way of the high-frequency heating-IR absorption method, and a Karl Fischer moisture content of 0.2 wt % or less when heated to 180&#xb0; C. and the method comprising the steps of applying a paste of active material for positive electrode to electrode plate to make an electrode, then drying the electrode, and pressing and then installing the electrode in a battery, in a work atmosphere having an absolute moisture content of 10 g/mor less.

Active material for positive electrode for non-aqueous electrolyte secondary battery and method of manufacturing the same

Finely-divided particulate bismuth oxide is produced by the steps of heating bismuth at 800.degree. C. or above in a first compartment of a sealed vessel divided into two compartments by a partition wall, the two compartments communicating with each other by a hole provided on the partition wall, feeding an inert gas such as nitrogen and argon into the first compartment so that the bismuth vapor formed by heating bismuth has a bismuth concentration of 0.1 to 0.5 g/liter, blowing air into the bismuth vapor introduced from the first compartment into the second compartment through the hole on the partition wall, permitting the air to mix with the bismuth vapor to form bismuth oxide and simultaneously cooling the thus formed bismuth oxide to 250.degree. to 300.degree. C., discharging by suction the bismuth oxide from the sealed vessel at a flow rate of 1 to 5 m/sec, and cooling the discharged bismuth oxide by supplying cooling air outside the sealed vessel.

Production of finely-divided particulate bismuth oxide

Scrap containing gallium and arsenic is treated with chlorine gas to form a crude gallium and arsenic chloride mixture. Arsenic chloride and impurities having a lower boiling point than that of arsenic chloride are removed from the mixture by vaporization so that crude gallium chloride may be obtained. The crude gallium chloride is purified by distillation. The purified gallium chloride is electrolyzed to yield metallic gallium. If the scrap has a molar gallium/arsenic ratio exceeding 1, arsenic chloride or metallic arsenic or both are added to the scrap before it if treated with chlorine gas.

Method of recovering gallium from scrap containing gallium

At least an equivalent amount of concentrated hydrochloric acid is added to antimony trioxide containing a substance emitting alpha rays, and they are stirred. Any undissolved residue is removed to prepare an aqueous solution of antimony chloride. Water is added to the solution, or a distillate obtained by distilling it at a temperature of at least 135.degree. C. The quantity of the water is at least 10 times by volume as much as the solution, or at least 20 times by volume as much as the distillate. The solution or distillate and the water are stirred at a temperature of at least 60.degree. C. to cause precipitation of antimony trioxide, and the precipitate is separated by filtration. The precipitate is washed with at least 10 times by weight as much warm water having a temperature of 60.degree. C., and dried. This antimony trioxide has an alpha-ray strength not exceeding 0.01 C/cm.sup.2 per hour, does not contain more than 1 ppm of any impurities such as arsenic, lead or soluble chlorine, and has a large average particle size.

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Niihama, Japan

Shigeki Kubo