Nippon Kodoshi Corporation

Sei Corporation

Juki Corporation

Masahiko Ueta

Atsushi Igawa

Norihiro Wada

Shinji Saito

Takehiko Sawai

Kazunori Urao

Naoki Fujimoto

Yoshiyo Kubo

Jyunichi Ushimoto

Yoshitada Hayashi

Masami Minami

Satomi Hara

Natsuko Yashiro

A separator for an electrochemical element suitable extends the service life of an electrochemical element under high temperature conditions. This separator for an electrochemical element is disposed between a pair of electrodes and is for separating the two electrodes from each other and retaining an electrolytic solution, wherein the separator contains a cellulose-based fiber, and the limiting viscosity of the separator as measured by the measurement method specified in JIS P 8215 is in a range of 150-500 ml/g.

Separator for electrochemical element and electrochemical element

A separator for an electrochemical element interposed between a pair of electrodes, capable of holding an organic electrolytic solution contains an electrolyte. The separator is a wet-laid nonwoven fabric containing 10-50 mass % of thermoplastic synthetic fibers and 50-90 mass % of beaten regenerated cellulose fibers having a mean fiber length of 0.2-2.0 mm, the separator has a thickness of 10-70 &#x3bc;m and a density of 0.25-0.90 g/cm3, including two parts obtained by bisecting a cross-section of the separator in a thickness direction. Two A-parts with a small number of the thermoplastic synthetic fibers and B-part with a large number of the thermoplastic synthetic fibers, and the A and B parts are formed into a single layer in an integrated manner; a value obtained by dividing the number of thermoplastic synthetic fibers in the A part by the number of the thermoplastic synthetic fibers in the B part is 0.85 or less.

Separator for electrochemical element, electrochemical element, automobile, and electronic device

The present invention provides an electrolyte holder for a lithium secondary battery capable of holding an electrolytic solution inside electrodes or at an interface between the separator and each of the electrodes, preventing electrolyte shortage inside the electrodes, and restraining dendrite from precipitating and growing and also provide the lithium secondary battery, using the electrolyte holder, which is capable of achieving a cycle life to such an extent that the lithium secondary battery can be used for industrial application. An electrolyte holder () for use in the lithium secondary battery consists of a multi-layer structure having at least two hydrophilic fibrous layers (A, B) having different porosities. The electrolyte holder () is composed of an electrode group formed by winding a cathode () and an anode () or laminating the cathode () and the anode () one upon another with an electrolyte holder () serving as a separator interposed between the cathode () and the anode (). The organic electrolytic solution is permeated into the electrode group or the electrode group is immersed in the organic electrolytic solution. A porosity (40% to 80%) of the fibrous layer (A) disposed at an interface between the fibrous layer (A) and the anode () is set smaller than a porosity (60% to 90%) of the fibrous layer (B) disposed at an interface between the fibrous layer (B) and the cathode (). An average porosity of the entire fibrous layer is set to not less than 50%. The fibrous layers are formed by using cellulose fibers as a main material thereof. An active substance for use in the anode () is a carbon material.

Electrolyte holder for lithium secondary battery and lithium secondary battery

A thin separator paper is provided for separating a positive electrode active material and a negative electrode active material from one another in alkaline battery. The separator paper has high gas tightness, high shortage preventing effect, and low deterioration. The separator paper possesses a crystalline structure in which celluloseand cellulosecoexist. A ratio of the celluloseis controlled in relation to the celluloseand the separator paper is made by using an alkali treated pulp beaten from CSF 50 ml to 0 ml, as a raw material. The separator paper has the thickness between 15 &#x3bc;m and 60 &#x3bc;m, the gas tightness between 10 minutes/100 ml and 800 minutes/100 ml, and the area shrinkage rate which is not greater than 2%. Also provided is an alkaline battery containing the separator paper.

Separator paper for alkaline battery and the alkaline battery

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Kochi, Japan

Masahiko Ueta