Provided is a long aluminum foil capable of suppressing, in a case where the aluminum foil is provided with a region where through-holes are not formed, occurrence of deformation at a boundary portion between a region where through-holes are formed and the region where through-holes are not formed. The long aluminum foil includes, in a width direction orthogonal to a longitudinal direction, a perforated portion, a non-perforated portion, and a boundary portion between the perforated portion and the non-perforated portion, in which the perforated portion has a plurality of through-holes penetrating therethrough in a thickness direction, the non-perforated portion does not have a through-hole, the boundary portion has a plurality of through-holes penetrating therethrough in the thickness direction and a plurality of non-through-holes, and an opening ratio of the through-hole in the boundary portion gradually decreases from a perforated portion side to a non-perforated portion side.

The present invention relates to: a current collector comprising a metal plate having a plurality of through holes formed in the thickness direction, and a porous reinforcing material filling the through holes of the metal plate; and a secondary battery comprising the current collector, and provides the effects of increasing ion conductivity of the current collector in the thickness direction and preventing stress from being concentrated at a specific part.

Provided are a lithium ion secondary battery electrode that occurrence of short-circuit and contamination can be reduced and the method for manufacturing such a lithium ion secondary battery electrode. An electrode used for a lithium ion secondary battery includes a current collector formed of a metal porous body. The current collector has a mixture layer impregnated with an electrode material mixture containing an electrode active material and a non-mixture-impregnated portion not impregnated with the electrode material mixture and including a tab portion and a tab converging portion. The surface roughness Ra of the non-mixture-impregnated portion is equal to or less than the surface roughness of the mixture layer.

An electrolyte element (10) comprises a perforated sheet (11) of non-reactive metal such as an aluminium-bearing ferritic steel, and a non-permeable ceramic layer (16b) of sodium-ion-conducting ceramic bonded to one face of the perforated sheet (11) by a porous ceramic sub-layer (16a). The perforated sheet (11) may be of thickness in the range 50 μm up to 500 μm, and the thickness of the non-permeable ceramic layer (16b) may be no more than 50 μm, for example 20 μm or 10 μm. Thus the electrolyte properties are provided by the non-permeable thin layer (16b) of ceramic, while mechanical strength is provided by the perforated sheet (11). The electrolyte element (10) may be used in a rechargeable molten sodium-metal halide cell, in particular a sodium/nickel chloride cell (20). It makes cells with increased power density possible.

The present invention provides a three-dimensional current collector used in a metal secondary battery and the preparation method of said current collector. Said current collector is a three-dimensional porous hollow carbon fiber current collector which has both porous structure and hollow structure and is used to load metal anode, so that lithium dendrites growth can be suppressed and the Coulombic efficiency can be improved. Said current collector is intertwined by micrometer-sized hollow carbon fibers with the diameter of 1 to 50 μm, the wall thick of 0.5 to 6 μm, and the pore volume of 0.005 to 0.05 cm.sup.3 cm.sup.−2.

To provide an electrode for a lithium-ion secondary battery that can reduce risk of a short circuit when a porous metal is used as a current collector.

An electrode for lithium-ion secondary battery having a positive electrode, a negative electrode, and an electrolyte disposed between the positive electrode and the negative electrode, the electrode comprising a current collector and a current collector tab, wherein the current collector is constituted by a metal porous body having voids in communication with each other, wherein a surface of the current, collector, including surfaces of the voids, is covered with an ion conductor layer, and wherein an electrode active material is disposed on the surface of the ion conductor layer of the voids.

An electrochemical cell that cycles lithium ions includes a positive electrode, a negative electrode current collector spaced apart from the positive electrode, and an ionically conductive electrolyte disposed between the positive electrode and the negative electrode current collector. The negative electrode current collector is of unitary one-piece construction and has a three-dimensional porous structure that defines an interconnected network of open pores. During charging of the electrochemical cell, lithium metal is deposited within the open pores of the negative electrode current collector.

To provide a solid-state battery in which the capacity and voltage can be optionally adjusted in a single battery and the installation space for the battery can be reduced. A solid-state battery includes a plurality of electrode layers, and a solid electrolyte layer disposed between the electrode layers. The electrode layers includes positive electrode portion formed by filling a current collector including a metal porous body with a positive electrode material mixture, negative electrode portion formed by filling a current collector including a metal porous body with a negative electrode material mixture, and an isolation portion formed between the positive electrode portion and the negative electrode portion. Between the plurality of electrode layers disposed adjacent to each other, the positive electrode portion and the negative electrode portion are disposed so as to face each other, and the isolation portions are disposed so as to face each other.

An electrode assembly of the present invention comprises a cathode active material layer, a cathode current collector, a separator, an anode current collector, and an anode active material layer, which are stacked in order, wherein the current collectors have a plurality of through-holes formed to allow communication between the upper surface and the lower surface of the current collector. The electrode assembly of the present invention has the effect of preventing a rapid temperature increase if an internal short caused by damage to the separator occurs.

Provided is an electrode for lithium ion secondary batteries in which an electrode material mixture is packed in porous metal, which electrode has excellent penetration of electrolyte solution and improved ion diffusivity. The electrode for lithium ion secondary batteries includes a current collector made of porous metal; and an electrode layer including an electrode material mixture including at least an electrode active material, in which the current collector is filled with the electrode material mixture, the current collector has an intermediate region and two surface regions in its thickness direction and m the electrode layer, the intermediate region has a porosity lower than that of the two surface region, and the intermediate region is filled with a first electrode active material, and the two surface regions are filled with a second electrode active material having a particle size larger than that of the first electrode active material.