Panasonic Corporation

Matsushita Electric Industrial Co., Ltd.

Junji Nakajima

Tsumoru Ohata

Tetsuya Hayashi

Shigeo Ikuta

Kohei Suzuki

Akiko Fujino

Takashi Takano

Masao Fukunaga

Kouji Nishida

Tsuyoshi Uemura

Yusuke Fukumoto

Kazuo Inoue

Masao Yamamoto

Hirofumi Wakemoto

Hideaki Mochizuki

Shinji Kasamatsu

Eitaro Nakamura

Akihiro Maeda

Naoto Hoshihara

A lithium ion secondary battery includes a positive electrode capable of absorbing and desorbing lithium ion, a negative electrode capable of absorbing and desorbing lithium ion, a porous film interposed between the positive electrode and the negative electrode, and a non-aqueous electrolyte, the porous film being adhered to a surface of at least the negative electrode. The porous film includes an inorganic filler and a first binder: The content of the first binder in the porous film is 1.5 to 8 parts by weight per 100 parts by weight of the filler: The first binder includes a first rubber including an acrylonitrile unit: The first rubber is water-insoluble and has a decomposition temperature of 250&#xb0; C. or higher. The negative electrode includes a negative electrode active material capable of absorbing and desorbing lithium ion and a second binder, and the second binder includes a second rubber particle and a water-soluble polymer.

Lithium ion secondary battery

A secondary battery includes: a positive electrode; a negative electrode; a porous electron-insulating layer adhered to a surface of at least one selected from the group consisting of the positive electrode and the negative electrode; and an electrolyte. The porous electron-insulating layer comprises a particulate filler and a resin binder, and the particulate filler comprises an indefinite-shape particle comprising a plurality of primary particles that are joined to one another. A neck is preferably formed between the primary particles. Since the porous electron-insulating layer has high porosity, it is possible to obtain a secondary battery that exhibits excellent low-temperature characteristics, which are particularly important in actual use, and that is capable of discharging at a large current.

Secondary battery

A lithium ion secondary battery includes a positive electrode capable of absorbing and desorbing lithium ion, a negative electrode capable of absorbing and desorbing lithium ion, a porous film interposed between the positive electrode and the negative electrode, and a non-aqueous electrolyte: the porous film being adhered to a surface of at least one of the positive electrode and the negative electrode; the porous film including a filler and a resin binder; the resin binder content in the porous film being 1.5 to 8 parts by weight per 100 parts by weight of the filler; and the resin binder including an acrylonitrile unit, an acrylate unit, or a methacrylate unit.

A method for producing a lithium ion secondary battery includes the steps of: forming a positive electrode mixture layer on a positive electrode substrate to obtain a positive electrode; forming a negative electrode mixture layer on a negative electrode substrate to obtain a negative electrode; forming an electronically insulating porous film that is bonded to a surface of at least one of the positive electrode and the negative electrode; interposing a separator between the positive electrode and the negative electrode to form an electrode plate assembly; and impregnating the electrode plate assembly with a non-aqueous electrolyte. The step of forming a porous film includes the steps of: preparing a porous film paste that contains a film binder comprising a thermo-cross-linkable resin and a particulate filler; and applying the porous film paste onto a surface of at least one of the positive electrode and the negative electrode and heating the resultant applied film.

Lithium ion secondary battery and method for producing the same

To provide a non-aqueous secondary battery having a capacity as high as that of a conventional battery using a conventional resin separator and achieving excellent overcharge characteristics and excellent resistance to external short-circuit, a combined electrode plate for a spirally-wound electrode group for a non-aqueous secondary battery including a current collector, an active material layer carried on the current collector and a multi-layer porous membrane carried on the active material layer is used. The multi-layer porous membrane includes a first porous membrane and a second porous membrane. The first porous membrane contains metal oxide particles and a first binder. The second porous membrane contains resin particles and a second binder. The thickness of the multi-layer porous membrane is preferably 15 to 25 &#x3bc;m.

Spirally-wound non-aqueous secondary battery and electrode plate used therefor

The present invention relates to a lead-acid battery Comprising a positive and a negative electrode, each having a current collector comprising an expanded grid, characterized in that at least one of the positive electrode and the negative electrode contains an organic binder in an active material layer at an edge portion thereof. This makes it possible to suppress an internal short circuit resulting from the separation or abnormal growth of an active material due to repeated charge/discharge, thereby remarkably prolonging the cycle life of a lead-acid battery.

Electrode for lead-acid battery

A lithium ion secondary battery comprising: a positive electrode, a negative electrode, a separator interposed between the positive and negative electrodes, and an electrolyte prepared by dissolving a lithium salt in a non-aqueous solvent, wherein the separator comprises a porous film layer containing basic solid particles and a composite binder, the porous film layer is adhered to at least one surface of at least one of the positive and negative electrodes, the composite binder comprises a primary binder and a secondary binder, the primary binder comprises polyether sulfone and the secondary binder comprises polyvinylpyrrolidone.

The present invention provides a light-modulation element comprising at least: liquid crystal droplets having a particle size between 0.6 &mgr;m-2 &mgr;m, which have light-modulating functions to scatter light rays or transmit light rays and polymer matrix having an interstructure thickness of 0.5 &mgr;m or less between the liquid crystal droplets. The light-modulation element works to scatter light rays or transmit light rays by turning on a voltage or turning off a voltage. The light-modulation element is produced by a polymerization process and a mixing step to separate out liquid crystal phases in a polymer matrix.

Light-modulation element and production method thereof

A mixed material of liquid crystals and resin is dropped on at least one substrate in an amount greater than the amount needed to cover a display area for the LCD panel. The substrate is adhered to another substrate, and excess material is removed to the outside of a display area. The phase-separation of the liquid crystals and resin is carried out by irradiating light while pressure is added to at least one substrate, so that a liquid crystal display panel applied to a liquid crystal display device or a light shutter can be manufactured without applying a complex vacuum device.

Growing community of inventors

Osaka, Japan

Junji Nakajima