Sanyo Electric Co., Ltd.

Mikiya Yamasaki

Koji Nishio

Yoshihiro Shoji

Toshiyuki Nohma

Yasuyuki Kusumoto

Toshihiko Saito

Kentaro Takahashi

A polymer electrolyte secondary cell that is superior in the cycle characteristic and security during cell overcharge is provided. The polymer electrolyte of the cell includes a non-aqueous solvent, a lithium salt, and a polymer. The non-aqueous solvent contains at least one of ethylene carbonate and propylene carbonate. The volume ratio (25&#xb0; C., 1 atm) of the ethylene carbonate and the propylene carbonate combined to the non-aqueous solvent is equal to or more than 60%. The polymer is made of a copolymer having a monomer containing N,N-dimethyl acrylamide and a compound with three or more acrylate groups and/or methacrylate groups. The ratio of the compound to the total mass of the monomer is from 10 to 30 mass %. The ratio of the polymer to the polymer electrolyte is from 1.0 to 2.0 mass %.

Polymer gel electrolyte secondary cell

A polymer electrolyte battery having a high discharge capacity, a high mechanical strength, and a high heat resistance is provided. This polymer electrolyte battery includes: a polymer electrolyte layer covering an edge face of a positive electrode plate and an edge part of a porous membrane ; a polymer electrolyte layer covering an edge face of a negative electrode plate and an edge part of the porous membrane ; and a polymer electrolyte layer covering an edge face of the porous membrane in a manner that connects the polymer electrolyte layer with the polymer electrolyte layer

Polymer electrolyte battery of high mechanical strength and high heat resistance, and method for producing the polymer electrolyte battery

The present invention is directed to a non-aqueous electrolyte battery comprising an anode, a cathode using a carbon material, and a non-aqueous electrolytic solution, wherein the carbon material obtained by coating a core composed of graphitized carbon in which spacing (d.sub.002) of lattice planes (002) is in the range of 3.35 to 3.39 .ANG. and the length (Lc) of a crystallite in the direction of the c axis is not less than 1000 .ANG. with coating graphitized carbon in which spacing (d.sub.002) of lattice planes (002) is more than that in the graphitizing carbon and is in the range of 3.36 to 3.48 .ANG., the carbon material obtained by coating a core composed of graphitized carbon in which spacing (d.sub.002) of lattice planes (002) is in the range of 3.35 to 3.39 .ANG. with a calcined product of an organic substance composed of carbon containing sulfur atoms, or the carbon material composed multi-phase graphitized carbon having two or more crystals respectively different crystallinities in one particle, the length (Lc) of a crystallite in the direction of the c axis in each of the crystals being not less than 10 .ANG., are used for the cathode.

Non-aqueous electrolyte battery

Disclosed is a nonaqueous electrolyte secondary battery including a negative electrode prepared by coating a substrate with a slurry comprising a carbon material, an alkali metal salt of carboxymethylcellulose, and a styrene-butadiene rubber and drying it, the alkali metal salt accounting for 0.5.about.2 weight % of the total weight of the carbon material, styrene-butadiene rubber, and CMC alkali metal salt. Because of the higher electrical conductivity of the CMC alkali metal salt used as the thickening agent than the conventional carboxymethylcellulose or its ammonium salt, the secondary battery of the invention including the above negative electrode has an excellent load characteristic.

Nonaqueous electrolyte secondary battery

A nonaqueous electrolyte battery comprises a positive electrode comprising a mixture of manganese dioxide and a fluorinated graphite as a positive electrode active material, a negative electrode comprising lithium metal or a substance capable of occluding and discharging lithium ion as a negative electrode material, and a nonaqueous electrolyte, said fluorinated graphite being represented by the formula (CFx)n wherein 1.2.ltoreq..times..ltoreq.1.4 and contained in said mixture in a ratio by weight of 0.1 to 4%. This battery undergoes minimal self discharge and has excellent storage capability, since reaction products formed by reaction of manganese dioxide and the nonaqueous electrolyte used minimally react with lithium on the negative electrode side.

Growing community of inventors

Hirakata, Japan

Mikiya Yamasaki