Sanyo Electric Co., Ltd.

Hitachi Chemical Company, Ltd.

Hideyuki Inomata

Koji Nishio

Ikuo Yonezu

Naoya Nakanishi

Ryuji Ohshita

Eiji Okutani

Satoshi Yoshida

Takeshi Maeda

Tatsuya Nishida

Mitsuzo Nogami

Mitsuzou Nogami

Masato Iwanaga

Masayuki Terasaka

Yoshihiro Shoji

Kouichi Takei

Hironori Marubayashi

Hiroshi Nakagawa

Kiyoshi Suzuki

Katsuya Imai

Keisuke Ooga

[Problem] To provide a rectangular nonaqueous electrolyte secondary battery for which the generation of a magnetic field due to current during use is suppressed and the danger of internal shorts between the positive electrode tab and negative electrode tab is reduced. [Solution] The positive electrode tab and negative electrode tab are both disposed at the beginning side of a winding for wound electrodes. An outer housing and sealing plate are welded in a state with the positive electrode tab sandwiched at a mating part of the outer housing and sealing plate. The negative electrode tab is electrically connected to a negative electrode terminal provided on the sealing plate. The positive electrode tab and negative electrode tab are divided by a space of 2-12 mm in the direction of battery width.

Nonaqueous electrolyte secondary battery

A method for manufacturing a sealed battery for the invention uses an outer canwith an opening and a sealing plateprovided with a rising part which rises perpendicularly from the middle of a flange on the entire circumference of or a part of the fitted face with the battery outer can. The method includes inserting the sealing plateinto the opening of the battery outer canso that the top faces of both the battery outer canand the flange of the sealing plateare substantially in the same plane, and irradiating the fitted part of the opening of the battery outer canand the sealing platewith a high energy beam for welding.

Sealed battery and method for manufacturing the same

In order to provide a nonaqueous electrolyte secondary battery negative electrode material that has an excellent discharging capacity, the charge/discharge efficiency and the charge load characteristics, a manufacturing method thereof, a nonaqueous electrolyte secondary battery negative electrode with the negative electrode material and a nonaqueous electrolyte secondary battery, the invention provides a nonaqueous electrolyte secondary battery negative electrode material including graphite particles that have a block-like structure where a plurality of flat graphite fine particles assembles or bonds non-parallel with each other, the aspect ratio of 5 or less and a volume of fine pores in the range of 10 to 10nm in a volume of 400 to 2000 cm/kg; and a layer of carbon formed on a surface of the graphite particle, wherein a ratio (by weight ratio) of the layer of carbon to the graphite particle is in the range of 0.001 to 0.01, a manufacturing method thereof, a nonaqueous electrolyte secondary battery negative electrode with the negative electrode material and a nonaqueous electrolyte secondary battery.

Non-aqueous electrolyte secondary battery-use cathode material, production method therefor, non-aqueous electrolyte secondary battery-use cathode and non-aqueous electrolyte secondary battery using the cathode material

A non-aqueous electrolyte secondary cell excellent in cycle characteristics is provided. This purpose is achieved by the following structure. A non-aqueous electrolyte secondary cell has a positive electrode having a positive electrode active material, a negative electrode having a negative electrode active material, and a non-aqueous electrolyte having a non-aqueous solvent and an electrolytic salt. The positive electrode active material has a lithium-cobalt compound oxide having added therein at least zirconium. The non-aqueous electrolyte has LiBFat from 0.05 to 1.0 mass % of a total mass of the non-aqueous electrolyte and unsaturated cyclic carbonate at from 1.0 to 4.0 mass %. The true density ratio of the positive electrode is 0.72 or greater, the true density ratio being represented by formula 1 shown below: (Formula 1) True density ratio=active material apparent density of electrode active material layer&#xf7;true density of active material.

Non-aqueous electrolyte secondary cell

Lithium secondary battery

A lithium secondary cell is disclosed in which a positive electrode plate and a negative electrode plate are spirally wound with a sheet of separator interposed therebetween. A plurality of positive electrode current collector tabs are attached to the positive electrode plate so that an interval is formed between the positive electrode current collector tabs in a longitudinal direction of the positive electrode plate, and a plurality of negative electrode current collector tabs are attached to the negative electrode plate so that an interval is formed between the plurality of the negative electrode current collector tabs in a longitudinal direction of the negative electrode plate. In a state of the positive electrode plate and negative electrode plate being wound together, the positive electrode current collector tabs and the negative electrode current collector tabs are so disposed as to face each other with the separator interposed therebetween.

Spirally-wound lithium secondary cell having a plurality of current collector tabs and method of manufacture

A method of manufacturing a cylindrical non-aqueous electrolyte secondary cell according to the present invention comprises a first step of forming a lead-attaching area on which an active material layer is not formed, in a positive electrode wherein a positive electrode active material layer is formed on both sides of the positive electrode current collector and a negative electrode wherein a negative electrode active material layer is formed on both sides of the negative electrode current collector, and winding the positive electrode and the negative electrode with disposing a separator therebetween so that the lead-attaching areas are protruded from the edges of the separator, and a second step of disposing a lead at an end part of the lead-attaching area with interposing a metal plate having a multiplicity of holes, and thereafter laser-welding the lead and the metal plate and the lead-attaching area by applying a laser beam with a spot diameter larger than a hole diameter of the metal plate. According to the present invention, it is feasible to laser-weld a lead to a lead-attaching area without fear of a short circuit resulting from the fusion in an electrode assembly caused by a laser beam.

Method of manufacturing cylindrical non-aqueous electrolyte secondary cell

Growing community of inventors

Moriguchi, Japan

Hideyuki Inomata