Matsushita Electric Industrial Co., Ltd.

Panasonic Corporation

Tsumoru Ohata

Tetsuya Hayashi

Kohei Suzuki

Shigeo Ikuta

Masao Fukunaga

Junji Nakajima

Akiko Fujino

Masaru Watanabe

Tatsuo Mifune

Kazunori Kubota

Yusuke Fukumoto

Takashi Takano

Akihiro Horikawa

Tousaku Nishiyama

Kouji Nishida

Akira Kuroda

Motoi Kawamura

Kazunori Sakamoto

Masaki Hirokoh

Shinji Kasamatsu

Eitaro Nakamura

Akira Hashimoto

Toshihide Murata

Takao Kuromiya

Yoriko Takai

Katsuhiro Okamoto

Kiyoshi Kobata

Koji Nishida

Hiroki Muraoka

Hiroshi Suzuki

Kazushige Kinoshita

Junjirou Awano

Kyoushige Shimizu

A method for producing lithium ion secondary batteries includes the steps of: (A) preparing an electrode sheet with lead-forming parts, (B) intermittently forming porous insulating layers containing an inorganic oxide filler and a binder on a surface of the electrode sheet excluding the lead-forming parts, (C) connecting a lead to each of the lead-forming parts, and (D) fabricating batteries by using the electrode sheet to which the leads are connected. The step B includes: the step of applying a slurry containing the inorganic oxide filler and the binder to the outer surface of a gravure roll, and transferring the slurry applied to the outer surface of the gravure roll on a surface of the electrode sheet that is being transported by a plurality of guide rolls excluding the lead-forming part; and the step of moving at least one selected from the gravure roll and the guide rolls to make the electrode sheet away from the gravure roll in the lead-forming part.

Method of producing lithium ion 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 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 having an electrode group that includes: a winding core, a positive electrode containing a positive electrode core member and a positive electrode active material layer, a negative electrode comprising a negative electrode core member and a negative electrode active material layer, and a porous film including a filler and a binder formed on at least one of the positive and negative electrodes which are wound around the winding core. The positive electrode and/or the negative electrode have/has, on the initial winding side, a region where the active material layer is carried on only one side of the core member and a region where the active material layer is carried on neither side of the core member, at a position closer to the initial winding position than the region where the active material layer is carried on only one side of the core member.

Lithium ion secondary battery and production method thereof

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

A method for producing a non-aqueous electrolyte secondary battery comprising the steps of: (i) mixing a positive electrode active material, a first binder A and a dispersion medium to prepare a paste A, the active material comprising a lithium-containing transition metal oxide; (ii) mixing a conductive agent, a second binder B and a dispersion medium to prepare a paste B, the conductive agent comprising carbon black; (iii) mixing the paste A and the paste B to prepare a positive electrode material paste C; (iv) applying the positive electrode material paste C onto a positive electrode core member and rolling and drying the resultant member to prepare a positive electrode; and (v) fabricating a battery using the positive electrode, a negative electrode and a non-aqueous electrolyte, wherein contact angle &#x3b8;between the non-aqueous electrolyte and the binder A and contact angle &#x3b8;between the non-aqueous electrolyte and the binder B satisfy the formula (1): &#x3b8;&#x2212;&#x3b8;&#x2267;15&#xb0;.

Production method of non-aqueous electrolyte secondary battery

Disclosed is an electrode for lithium ion secondary batteries which includes an active material layer containing active material particles and a porous insulating layer formed on the surface of the active material layer. The porous insulating layer includes an inorganic filler and a resin binder, and the surface of the active material layer has a first region on which the porous insulating layer is formed, and a second region on which the porous insulating layer is not formed. By using such an electrode, a lithium ion secondary battery can have a high capacity, excellent characteristics and improved safety.

Electrode for lithium ion secondary batteries, lithium ion secondary battery using the same, and method for manufacturing the battery

A lithium ion secondary battery in which an abnormal overheat due to a short circuit of a current collecting portion of one electrode and an electrode material mixture of the other is prevented. The lithium ion secondary battery has: a positive electrode including a core material having a current collecting portion and a material mixture carrying portion and a material mixture layer carried thereon; a negative electrode including a core material having a current collecting portion and a material mixture carrying portion and a material mixture layer carried thereon; a separator and a porous electron-insulating layer including an inorganic oxide filler and a binder both interposed between the positive and negative electrodes; and a non-aqueous electrolyte. The insulating layer is carried on a region including surfaces of the positive electrode current collecting portion and material mixture layer, and/or a region including surfaces of the negative electrode current collecting portion and material mixture layer. The positive and negative electrodes are wound with the separator and the insulating layer interposed therebetween.

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

Method for producing lithium ion secondary battery

A lithium ion secondary battery has an electrode group including: a winding core; and a positive electrode and a negative electrode that are wound around the winding core. This electrode group does not have an independent separator between the positive and negative electrodes. A porous film is integrally formed on both sides of at least one of the positive electrode and the negative electrode. The negative electrode and the positive electrode are connected to the winding core by a negative electrode resin film and a positive electrode resin film, respectively. The use of such resin films makes it possible to reduce the breakage of the porous films and prevent a short-circuit between the positive and negative electrodes.

Lithium ion secondary battery and method for manufacturing the same

Growing community of inventors

Kyoto, Japan

Tsumoru Ohata