The multilayer copper foil includes: a recrystallization active layer disposed on a surface of a substrate; and a recrystallization suppressing layer disposed on a surface of the recrystallization active layer to inhibit recrystallization of the recrystallization active layer, wherein a concentration of impurities within the recrystallization suppressing layer is greater than a concentration of impurities within the recrystallization active layer.

The multilayer copper foil includes: a recrystallization active layer disposed on a surface of a substrate; and a recrystallization suppressing layer disposed on a surface of the recrystallization active layer to inhibit recrystallization of the recrystallization active layer, wherein a concentration of impurities within the recrystallization suppressing layer is greater than a concentration of impurities within the recrystallization active layer.

A composite metal foil and a preparation method thereof are provided. The composite metal foil includes a carrier layer, a barrier layer, a striping layer, and a metal foil layer. The carrier layer, the barrier layer, the striping layer, and the metal foil layer are sequentially stacked, the barrier layer includes a metal bonding layer and a high-temperature resistant layer stacked, and the metal bonding layer is disposed between the carrier layer and the high-temperature resistant layer. The striping layer is disposed between the carrier layer and the metal foil layer so as to facilitate peeling of the carrier layer, and the barrier layer is disposed between the carrier layer and the metal foil layer so as to prevent the carrier layer and the metal foil layer from diffusing mutually to cause bonding at a high temperature, so that the carrier layer and the metal foil layer are easy to peel off. In addition, the metal bonding layer is disposed between the carrier layer and the high-temperature resistant layer, so that the barrier layer is not easy to separate from the carrier layer, and peeling between the barrier layer and the carrier layer is prevented.

Provided is an electrodeposited copper foil having high smoothness and exhibiting high flexibility (particularly, high flexibility after annealing at 180° C. for 1 hour) suitable for a flexible substrate. This electrodeposited copper foil has an Rz of 0.1 to 2.0 μm on at least one surface. In cross-sectional analysis by EBSD, a proportion of an area occupied by copper crystal grains satisfying the following conditions relative to an area of an observation field occupied by copper crystal grains is 63% or more. The conditions are as follows: i) (101) orientation; ii) an aspect ratio of 0.500 or less; iii) | sin θ| of 0.001 to 0.707, where θ)(°) is an angle between a normal line of an electrode surface of the electrodeposited copper foil and a major axis of the copper crystal grain; and iv) when the crystal is elliptically approximated, a length of a minor axis of 0.38 μm or smaller.

Stacked magnetic cores that can achieve high density with a small footprint, as well as methods of fabricating and using the same, are provided. A stacked magnetic core can be fabricated by depositing nanomagnetic films with control in composition and nanostructure via a continuous electroplating process. The magnetic films are interspersed with thin adhesive films (that can be insulating) in an automated roll-to-roll process. That is, the magnetic films and adhesive films are disposed in an alternating fashion. The adhesive films can keep the magnetic films completely electrically isolated from each other, while also adhering adjacent magnetic films to each other.

Stacked magnetic cores that can achieve high density with a small footprint, as well as methods of fabricating and using the same, are provided. A stacked magnetic core can be fabricated by depositing nanomagnetic films with control in composition and nanostructure via a continuous electroplating process. The magnetic films are interspersed with thin adhesive films (that can be insulating) in an automated roll-to-roll process. That is, the magnetic films and adhesive films are disposed in an alternating fashion. The adhesive films can keep the magnetic films completely electrically isolated from each other, while also adhering adjacent magnetic films to each other.

A tab, a preparation method thereof, and a battery including the tab are disclosed. The tab is a copper foil material, a surface of the copper foil material having a large compressive stress is an S surface, a surface having a small compressive stress is an M surface, and only the M surface is provided with an indentation or a reinforcing rib. In the preparation method of the tab of the disclosure, the S surface/M surface of the copper foil material are identified, and it is ensured that a feed direction is oriented so that the M surface faces outward (or inward), and winding/unwinding directions of each process and a mounting direction of an embossing device are reasonably fixed, so as to ensure that a tab emboss pattern of a product is pressed on the M surface of the copper foil material rather than the S surface or both surfaces.

Disclosed is a method for preparing a high-flatness metal foil suitable for making a metal mask, and the method comprises the following steps: forming a raw metal coarse foil; rolling the raw metal coarse foil at least once into a high-flatness metal foil; performing, by a heat treatment device, heat treatment processing on the precisely rolled metal foil according to a preset temperature and a preset time; using a tension leveler to perform tension leveling on the rolled and heat-treated metal foil; and obtaining a high-flatness metal foil after completion of the tension leveling and forming a rolled metal foil in a continuous forming process. The resulting metal foil has high flatness and low residual stress, which improves quality and performance of the metal foil and is suitable for the fabrication of fine metal masks.

Disclosed is a method for preparing a high-flatness metal foil suitable for making a metal mask, and the method comprises the following steps: forming a raw metal coarse foil; rolling the raw metal coarse foil at least once into a high-flatness metal foil; performing, by a heat treatment device, heat treatment processing on the precisely rolled metal foil according to a preset temperature and a preset time; using a tension leveler to perform tension leveling on the rolled and heat-treated metal foil; and obtaining a high-flatness metal foil after completion of the tension leveling and forming a rolled metal foil in a continuous forming process. The resulting metal foil has high flatness and low residual stress, which improves quality and performance of the metal foil and is suitable for the fabrication of fine metal masks.

A surface-treated copper foil includes a treated surface, where the peak extreme height (Sxp) of the treating surface is 0.4 to 3.0 μm. When the surface-treated copper foil is heated at a temperature of 200° C. for 1 hour, the ratio of the integrated intensity of diffraction peak of (111) plane to the sum of the integrated intensities of diffraction peaks of (111) plane, (200) plane, and (220) plane of the treating surface is at least 60%.