Sony Corporation

Other

Takayuki Yamahira

Hiroyuki Yamada

Yoshiaki Takeuchi

Fumihiko Suzuki

Kazuo Togashi

Toru Ishii

Osamu Takahashi

Atsuo Yamada

Masaru Hiratsuka

Toru Nagaura

Hisayuki Kato

Masanori Anzai

Norio Mamada

Yoshinori Hashimoto

Ayaki Watanabe

Koji Kihara

Toshizou Kameishi

A battery pack is provided. For example, the battery pack includes a box-shaped or plate-shaped battery pack. The battery pack has a hard outer jacket member, a box-shaped or plate-shaped battery element, a cover, and a circuit board. The hard outer jacket member has a first opening and a second opening formed at both ends. The box-shaped or plate-shaped battery element is contained in the outer jacket member and has electrode terminals. The cover is molded from resin and is fitted to the first opening. The circuit board is connected to the electrode terminal leads and contained in the cover. At least the electrode terminal leads extends from the first opening. The cover has concave portions on both ends of one longer side. The outer jacket member has cut portions that expose at least the concave portions of the cover. At least a longer side of the cover and the outer jacket member are heat-adhered.

Battery pack

A battery pack which can increase of the volumetric efficiency of the battery pack without being contained in a resin mold case is provided. A first laminate material has a concave portion formed by drawing where a battery element is contained. A second laminate material is stacked so as to cover the opening of the concave portion to seal up the periphery of the opening. The first and second laminate materials are bend inwards so as to cover the battery element, and bonded and fixed together by heating. The first laminate material has three-layer structure including a polypropylene layer, a soft aluminum layer, and a nylon layer or PET layer. The second laminate material has a similar structure but includes a hard aluminum layer. Therefore, the second laminate material has enough strength to resist deformation without being contained a cell in a resin mold case.

A lithium ion cell less costly than a control lithium ion cell is provided. The lithium ion cell is improved appreciably in operational stability under special conditions, such as high temperatures, and exhibits superior characteristics against over-discharging, while guaranteeing compatibility to the operating voltage of a conventional lithium ion cell and an energy density equivalent to that of the conventional lithium ion cell. To this end, the lithium ion cell includes a positive electrode, a negative electrode and a non-aqueous electrolyte, and uses, as a positive electrode active material, a composite material of a first lithium compound represented by the general formula Li M PO , where 0<x<2, 0.8<y<1.2 and M contains Fe, and a second lithium compound having a potential holder than the potential of the first lithium compound.

Lithium phosphate composite positive electrode and non-aqueous electrolyte cell

A rectangular and sealed battery incorporating an outer can for accommodating a power generation element and a cover for closing an opening of the outer can such that the outer can and the cover are welded to each other. The thickness of a body portion of the outer can is smaller than the thickness of the opening. A flange formed into a stepped portion is provided for the outer end of the cover, and the end of the opening of the outer can is made contact with the outer surface of a projection of the cover formed by the stepped portion so as to be joined to the outer surface of the projection and butt-welded to the flange. In the foregoing case, the cover and the end of the opening of the outer can are welded to each other from a side direction.

Rectangular and sealed battery

An extremely safe non-aqueous electrolyte secondary cell free of explosions and which can promptly release the internal pressure in case of rise in the internal pressure. The non-aqueous electrolyte secondary cell has in its opening a cleavage valve obtained on bonding a metal foil to the opening. In case of rise in the internal pressure, the cleavage valve is cleft to release the pressure. In this cell, a value K corresponding to the internal volume in the cell in cm divided by the area of the opening in cm is set so that 40&lE;K&lE;350. By selecting the value K to a suitable value, the cleavage valve is in operation when the internal pressure reaches a predetermined value to release the pressure. The metal foil is produced by, for example, a electro-forming method or a cladding method. Preferably, a fluorine-based water-proofing agent is coated on the foil surface.

Non-aqueous electrolyte secondary cell

A method for producing an active anode substance includes: a step for preparing, with mesophase carbon as a starting material, two carbon materials different in calcination temperature; a step for combining the two carbon materials at a specified ratio, turning the mixture into particles, and molding them into a shaped body; and a step for sintering the shaped body in an atmosphere of an inert gas or in a vacuum into a sintered anode body.

Anode material, method for producing it and nonaqueous electrolyte cell employing such anode materials

A non-aqueous electrolyte secondary cell including a negative electrode mainly composed of a carbonaceous material, lithium metal or a lithium alloy, a positive electrode mainly composed of a sintered mass of a lithium compound oxide and a non-aqueous electrolyte.

A non-aqueous electrolyte secondary cell having a negative electrode, a positive electrode and a non-aqueous electrolytic solution, in which a carbonaceous material is used as an active negative-electrode material, is disclosed. The negative electrode is constituted by a carbon sintered mass obtained on sintering the carbonaceous material or a carbon sintered mass-current collector composite material. The secondary cell is improved in the amount of the active material packed in the negative electrode, energy density and in the charging/discharging efficiency. If the carbon sintered mass-current collector composite material is employed for the negative electrode, further improvement in the electrical conductivity and charging/discharging efficiency in the negative electrode is achieved.

There is disclosed a non-aqueous electrolyte secondary battery in which carbonaceous material is used as the anode active material and charge/discharge is carried out by doping/undoping of lithium. The carbonaceous material has a grading distribution such that the 10% cumulative or accumulated diameter is 6 to 20 .mu.m, the 50% cumulative diameter is 20 to 55 .mu.m, and the 90% cumulative diameter is 55 to 90 .mu.m. When a carbonaceous material such that the grading distribution satisfies the above condition is used as the anode active material, the self-discharge rate is suppressed and occurrence of an internal short-circuit is also prevented.

Non-aqueous electrolyte secondary battery

A nonaqueous electrolyte secondary battery is disclosed, which comprises an anode having a carbonaceous material as the anode active material which permits lithium to be doped and undoped and a current collector, a cathode having a lithium compound as the cathode active material which permits lithium to be doped and undoped, and a nonaqueous electrolyte. The cathode active material contains the primary active material of a first lithium compound having the potential which is more 'noble' than the potential of the current collector and the auxiliary active material of a second lithium compound having the potential which is more 'base' than the potential of the current collector. The auxiliary active material works to avoid the dissolution of the anode current collector at the final stage of discharge.

Growing community of inventors

Fukushima, Japan

Takayuki Yamahira