Sanyo Electric Co., Ltd.

Atsutoshi Ako

Masao Takee

Yoshifumi Magari

Kazuaki Tamura

Akira Nishida

Masao Inoue

Teruhiko Imoto

Tomoyuki Yamada

Yasuhiko Ikeda

Kentaro Tsukamoto

Makoto Ochi

Kazuhiro Kitaoka

Tetsuyuki Murata

Yasuyuki Harada

Shuhei Yoshida

Yasumasa Kondo

A secondary battery provided with: a belt-like positive electrode plate having a plurality of positive electrode tabs; and a positive electrode current collector which is connected so that the plurality of positive electrode tabs are stacked, wherein the positive electrode plate has a positive electrode core body and a positive electrode active material layer formed on the positive electrode core bodies. At one edge side of the positive electrode plate where the plurality of positive electrode tabs are provided, one surface of the positive electrode core body has formed thereon a first protrusion that protrudes from said surface of the positive electrode core body in the thickness direction of the positive electrode core body, whereas the other surface of the positive electrode core body has no protrusion formed to protrude from said other surface of the positive electrode core body in the thickness direction of the positive electrode core body.

Secondary battery

A positive electrode plate that has a positive electrode active material layer formed on a positive electrode core, wherein the positive electrode core has, on an edge side, a thick portion which has a thickness that is greater than the thickness of a portion of the positive electrode core that has the positive electrode active material layer formed on both sides, and the positive electrode plate has a first region that extends into the thick portion from the portion of the positive electrode core that has the positive electrode active material layer formed on both sides and a second region that is positioned outside the first region in the thick portion. The average maximum diameter of the metal crystal grains that compose the first region is smaller than those of the second region.

Electrode plate and method for manufacturing same, and secondary battery and method for manufacturing same

The nonaqueous electrolyte secondary battery according to one embodiment includes a flat wound electrode body in which a positive plate and a negative plate are wound via a separator and characterized in that the positive plate has a positive core and a positive mixed material layer that is formed on both sides of the positive core, the positive mixed material layer includes a lithium metal composite oxide represented by general formula Li1+xMaO2+b (in the formula, x, a, and b satisfy the conditions x+a=1, −0.2<x≤0.2, and −0.1≤b≤0.1, and M includes Ni and Co and at least one element selected from the group consisting of Mn and Al), and the positive plate has a flexibility index of 15 to 19. Such a positive plate is capable of having a high packing density while suppressing cracks in the positive mixed material layer and buckling of the positive plate and the negative plate.

Method for manufacturing nonaqueous electrolyte secondary battery and nonaqueous electrolyte secondary battery

An alkaline storage battery system according to an aspect of the present invention, with which a partial charging-discharging is performed, includes an alkaline storage batteryincluding an electrode group having a nickel positive electrode, a hydrogen storage alloy negative electrode, a separator; an alkaline electrolyte; and an outer canaccommodating the electrode group and the alkaline electrolyte, and further includes a partial charge-discharge control unit for controlling charging-discharging of the battery. In addition, zinc (Zn) is added to nickel hydroxide that is a main positive electrode active material in the nickel positive electrodewith an addition amount of 5% by mass or less with respect to the mass of nickel in the positive electrode active material. The concentration of the alkaline electrolyte is 6.5 mol/L or less and the content of lithium in the alkaline electrolyte is 0.3 mol/L or more.

Alkaline storage battery system

In a rectangular alkaline storage battery, the sides of negative cores of negative electrode plates , which are disposed at the outermost positions of the group of electrode plates and oppose an outer casing can , are exposed. The pore ratios (ratio of total area taken up by pores to area of electrode plate) of the exposed cores must be made lower than those of the other unexposed cores. The pore ratio of the exposed negative core is specified as falling within a range of 10% to 40%. As a result, the negative electrode plates are improved in binding strength, thereby inhibiting exfoliation of an active material. Further, there can be obtained a large rectangular alkaline storage battery which has superior permeability for a gas which would arise in the battery, an improved capacity ratio, and greater volumetric energy density.

Rectangular alkaline storage battery

An active material slurry obtained by a mixing a powder of the active material with a binder and a solvent for the binder is heated to a predetermined temperature inside a slurry reservoir and the heated active material slurry is coated and adhered to an electrically conductive core body The resulting body is then fed inside a drying furnace to dry the coated and adhered active material slurry by heating, and is rolled to a predetermined thickness by passing it through a pair of rolling rolls thereby obtaining an electrode for alkaline batteries comprising an active material layer on the both sides of the electrically conductive core body On drying the active material slurry that is coated and adhered to the electrically conductive core body the transfer of the binder inside the active material slurry is suppressed, such that the decrease in the amount of the binder inside the active material layer in the vicinity of the electrically conductive core body is prevented from occurring. Thus is obtained an electrode for alkaline batteries improved in adhesion strength.

Growing community of inventors

Itano-gun, Japan

Atsutoshi Ako