Abstract: An initial charging operation is carried out by a charging step composed of two-stages or more to improve an initial charging and discharging efficiency, reduce the charge of wasteful materials and improve a high capacity and a high cyclic characteristic without deteriorating various kinds of battery properties. In order to realize the improvements, a nonaqueous solvent which is decomposed under a potential higher than the reduction and decomposition potential of a main solvent is included in electrolyte. This charging method is a method for achieving the addition effect of such a nonaqueous solvent as much as possible. As a specific means, the electrolyte to which vinylene carbonate is added is employed and a constant-current and constant-voltage charge under about 3.2 V is carried out for 1 to 2 hours before a battery is completely charged. Thus, a good coat can be formed on the surface of an anode while suppressing the quantity of electricity required for forming the coat.

Abstract: The present invention provides a gel electrolyte cell including a non-aqueous electrolytic solution containing lithium-containing electrolyte salt solved in a non-aqueous solvent and made into a gel state by a matrix polymer, and the gel electrolyte contains vinylene carbonate or derivative thereof in the amount not less than 0.05 wt % and not greater than 5 wt %. This gel electrolyte exhibits an excellent chemical stability with the negative electrode, strength, and liquid-retention characteristic. This gel electrolyte enables to obtain a gel electrolyte cell satisfying the cell capacity, cycle characteristic, load characteristic, and low-temperature characteristic.

Abstract: A gel electrolyte comprised of a non-aqueous electrolytic solution immersed in a matrix polymer, in which ion conductivity of a solvent is improved and superior cyclic characteristics are achieved. To this end, the gel electrolyte includes an electrolyte, a matrix polymer and a non-aqueous solvent. The non-aqueous solvent is a mixed solvent of ethylene carbonate (EC), propylene carbonate (PC) and &ggr;-butyrolactone (GBL). The non-aqueous solvent is of a weight composition in an area in a triangular phase diagram (EC, PC, GBL) surrounded by a point (70, 30, 0), a point (55, 15, 30), a point (15, 55, 30) and a point (30, 70, 0). A gel electrolyte battery employing this electrolyte is also disclosed.

Abstract: A gel electrolyte in which nonaqueous electrolyte solution obtained by dissolving electrolyte salt containing Li in a nonaqueous solvent is gelled by a matrix polymer including a copolymer as a main component which contains vinylidene fluoride as a monomer unit. The copolymer employed as the matrix polymer is carboxylic acid modified polyvinylidene fluoride into which a structure formed by esterifying a part or all of a carboxyl group, a carboxylic acid or an acetic anhydride structure is introduced. The carboxylic acid modified polyvinylidene fluoride can dissolve and retain therein a solvent of low viscosity having a low boiling point. Therefore, the carboxylic acid modified polyvinylidene fluoride is used as a matrix polymer to improve the ionic conductivity of the gel electrolyte at low temperature. Thus, a low temperature characteristic is improved and a cyclic characteristic and a load characteristic are also improved.

Abstract: An initial charging operation is carried out by a charging step composed of two-stages or more to improve an initial charging and discharging efficiency, reduce the charge of wasteful materials and improve a high capacity and a high cyclic characteristic without deteriorating various kinds of battery properties. In order to realize the improvements, a nonaqueous solvent which is decomposed under a potential higher than the reduction and decomposition potential of a main solvent is included in electrolyte. This charging method is a method for achieving the addition effect of such a nonaqueous solvent as much as possible. As a specific means, the electrolyte to which vinylene carbonate is added is employed and a constant-current and constant-voltage charge under about 3.2 V is carried out for 1 to 2 hours before a battery is completely charged. Thus, a good coat can be formed on the surface of an anode while suppressing the quantity of electricity required for forming the coat.

Abstract: An inorganic compound with a specific inductive capacity not less than 12 is contained in a separator. This improves the degree of ion dissociation of a lithium compound as an electrolytic salt contained in an non-aqueous solvent present in and near voids of pores, while diminishing resistance against ion conduction to improve ion conductivity.

Abstract: A solid electrolyte cell in which oxidative decomposition of electrolyte components is suppressed to maintain the superior cell performance. The solid electrolyte includes a negative electrode 9 having a negative electrode current collector 7 and a negative electrode active material 8, a positive electrode 12 having a positive electrode current collector 10 and a positive electrode active material 11 and a solid electrolyte 13 arranged between the negative electrode 9 and the positive electrode 12 and which is comprised of an electrolyte salt dispersed in a matrix polymer. A diene compound is contained in at least one of the positive electrode 12 and the solid electrolyte 13.

Abstract: A lithium cell, having positive and negative electrodes capable of occluding and releasing lithium and a non-aqueous electrolyte. The cell of the present invention includes a positive electrode, a negative electrode and a gelated electrolyte composed of a polyacrylonitrile containing high molecular material, a &ggr;-caprolactone containing non-aqueous solvent and an electrolyte salt mainly comprised of LiPF6, with the content of &ggr;-caprolactone in the gelated electrolyte being 30 mol % or less. With the gelated electrolyte composed of the polyacrylonitrile containing high molecular material, non-aqueous solvent and the electrolyte salt mainly composed of LiPF6, a carbide film is formed on the electrode surface, on contact with the flame, as a result of the carbonization of the high molecular material and the carbonization accelerating operation of LiPF6. This carbide film inhibits inflammation for realizing superior combustion retardant properties.

Abstract: A gel electrolyte in which nonaqueous electrolytic solution having a lithium-containing electrolyte salt dissolved in a nonaqueous solvent is gelled by a matrix polymer. The gel electrolyte includes a halogen substituted ethylene carbonate obtained by replacing one or more hydrogen atoms of ethylene carbonate by halogens. Since the halogen substituted ethylene carbonate (for instance, fluorinated ethylene carbonate) is extremely low in its reactivity with a negative electrode, a loss capacity is small so that it is very effective for obtaining a high capacity. Further, the halogen substituted ethylene carbonate has a melting point lower than that of ethylene carbonate, it can realize a large capacity with less deterioration of a low temperature performance than that of ethylene carbonate.

Abstract: A thin type cell is made up of a cathode 1, an anode 2 and an electrolyte 3, sheathed within a moisture-proofing multi-layered film 4 comprising a heat fusible layer and a metal foil. A pair of electrode terminals 5, 6 interconnecting electrodes and external terminals are formed of a netted or porous electrically conductive member. By using the netted or porous electrically conductive materials as the electrode terminals 5, 6, the electrode terminals 5, 6 can be firmly bonded to the moisture-proofing multi-layered film 4. Moreover, by increasing the thickness of the heat fusible layer at the sealing portion X passed through by the electrode terminals 5, 6, shorting can be prevented from occurring.

Abstract: A gel electrolyte secondary cell in which discharge capacity loss can be suppressed even with the use of a graphitized carbonaceous material of a small particle size as a negative electrode material to assure low impedance, superior cell voltage and load characteristics and high charging/discharging efficiency. To this end, a graphitized carbonaceous material prepared by firing meso-carbon micro-beads is used as a material for a negative electrode 9.