A surface-treated copper foil including a treating surface, where the root mean square height (Sq) of the treating surface is in a range of 0.20 to 1.50 μm and the texture aspect ratio (Str) of the treating surface is not greater than 0.65. When the surface-treated copper foil is heated at a temperature of 200° C. for 1 hour, the ratio of the integrated intensity of (111) peak to the sum of the integrated intensities of (111) peak, (200) peak, and (220) peak of the treating surface is at least 60%.

A nanocrystalline material based on a stainless steel surface. In percentage by weight, the nanocrystalline material comprises: 0 to 3% of carbon, 20% to 35% of oxygen, 40% to 53% of chromium, 10% to 35% of ferrum, 0 to 4% of molybdenum, 1% to 4% of nickel, 0 to 2.5% of silicon, 0 to 2% of calcium, and the balance of impurity elements. Also disclosed is a preparation method for the nanocrystalline material, and the nanocrystalline material that is based on a stainless steel surface and that is prepared by using the preparation method.

A nanocrystalline material based on a stainless steel surface. In percentage by weight, the nanocrystalline material comprises: 0 to 3% of carbon, 20% to 35% of oxygen, 40% to 53% of chromium, 10% to 35% of ferrum, 0 to 4% of molybdenum, 1% to 4% of nickel, 0 to 2.5% of silicon, 0 to 2% of calcium, and the balance of impurity elements. Also disclosed is a preparation method for the nanocrystalline material, and the nanocrystalline material that is based on a stainless steel surface and that is prepared by using the preparation method.

A microporous plating solution characterized by containing nonconductive particles and polyaluminum chloride allows for easy preparation of positively charged nonconductive particles and is highly stable. Then, a method for performing microporous plating on an object to be plated, characterized by plating the object to be plated in the microporous plating solution results in a favorable number of micropores in the plating.

Provided are an electrodeposited copper foil, a current collector, an electrode, and a lithium-ion secondary battery comprising the same. The electrodeposited copper foil has a deposited side and a drum side opposite the deposited side. In a first aspect, ΔRS between the deposited side and the drum side is at most about 95 MPa, and the deposited side exhibits a Vv in a range from about 0.15 μm.sup.3/μm.sup.2 to about 1.35 μm.sup.3/μm.sup.2. In a second aspect, the deposited side has a Sku of about 1.5 to about 6.5 and the deposited side exhibits a Vv in a range from about 0.15 μm.sup.3/μm.sup.2 to about 1.35 μm.sup.3/μm.sup.2. The characteristics are beneficial to improve the quality of the electrodeposited copper foil, thereby extending the charge-discharge cycle life of a lithium-ion secondary battery comprising the same.

A steel sheet for can making and methods for manufacturing the same. The steel sheet includes, in order from a steel sheet side, an iron-nickel diffusion layer, a metallic chromium layer, and a chromium oxide layer. The iron-nickel diffusion layer has a nickel coating weight of 50 mg/m.sup.2 to 500 mg/m.sup.2 per surface of the steel sheet and a thickness of 0.060 μm to 0.500 μm per surface of the steel sheet. The metallic chromium layer includes a flat-like metallic chromium sublayer and a granular metallic chromium sublayer placed on a surface of the flat-like metallic chromium sublayer. The total chromium coating weight of both sublayers per surface of the steel sheet is 60 mg/m.sup.2 to 200 mg/m.sup.2. The chromium oxide layer has a chromium coating weight 3 mg/m.sup.2 to 10 mg/m.sup.2 per surface of the steel sheet in terms of metallic chromium.

A steel sheet for can making and methods for manufacturing the same. The steel sheet includes, in order from a steel sheet side, an iron-nickel diffusion layer, a metallic chromium layer, and a chromium oxide layer. The iron-nickel diffusion layer has a nickel coating weight of 50 mg/m.sup.2 to 500 mg/m.sup.2 per surface of the steel sheet and a thickness of 0.060 μm to 0.500 μm per surface of the steel sheet. The metallic chromium layer includes a flat-like metallic chromium sublayer and a granular metallic chromium sublayer placed on a surface of the flat-like metallic chromium sublayer. The total chromium coating weight of both sublayers per surface of the steel sheet is 60 mg/m.sup.2 to 200 mg/m.sup.2. The chromium oxide layer has a chromium coating weight 3 mg/m.sup.2 to 10 mg/m.sup.2 per surface of the steel sheet in terms of metallic chromium.

Surface-treated copper foils exhibiting a void volume (Vv) in a range of 0.4 to 2.2 μm.sup.3/μm.sup.2 and an arithmetic mean waviness (Wa) lower than or equal to 0.4 μm are reported. Where the surface-treated copper foil is treated on the drum side and includes a treatment layer comprising a nodule layer. Such surface-treated copper foils can be used as a conductive material having low transmission loss, for example in circuit boards.

An electrolyte and a method to electroplate a metal on a substrate using the electrolyte are described. The electrolyte includes an imidazolium compound, a metal salt, and water. The imidazolium compound has formula (I) ##STR00001##
wherein R.sup.1, R.sup.2, R.sup.3, R.sup.4, and R.sup.5 are each independently selected from an H atom and an organic radical. L.sup.− is a compatible anion. The metal salt can include but is not limited to salts of the metals Li, Mg, Ca, Cr, Mn, Fe, Co, Ni, Cu, Zn, Cd, Pb, Bi, La, Ce, Al, Ag, Au, Ga, V, In, Nb, Mo, and W.

Provided are an electrodeposited copper foil, an electrode comprising the same, and a lithium-ion secondary battery comprising the same. The electrodeposited copper foil has a drum side and a deposited side opposing the drum side, wherein at least one of the drum side and the deposited side exhibits a void volume value (Vv) in the range of 0.17 μm.sup.3/μm.sup.2 to 1.17 μm.sup.3/μm.sup.2; and an absolute value of a difference between a maximum height (Sz) of the drum side and a Sz of the deposited side is in the range of less than 0.60 μm.