JP2018125280A - Surface treated copper foil, and current collector, electrode, and battery using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a surface-treated copper foil for a battery which has less dropping off of roughening particles and can obtain good adhesion with an active material.SOLUTION: A surface-treated copper foil for a battery according to the present invention includes a copper foil and a surface treatment layer on at least one surface side of the copper foil, and the surface treatment layer includes a primary particle layer and a secondary particle layer, and the ten point average roughness Rz when the surface treatment layer is measured by using a laser microscope with a wavelength of 405 nm according to JIS B0601 1994 is 1.8 μm or more.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a surface-treated copper foil and a current collector, an electrode and a battery using the same.

  A rolled copper foil and an electrolytic copper foil are used as a current collector for a positive electrode or an electrode of a battery, particularly a secondary battery. In any copper foil, high adhesion between the positive electrode or negative electrode active material and the copper foil as a current collector is required. In order to improve adhesion, there is an example in which a surface treatment for forming irregularities on the copper foil surface is performed. For example, as disclosed in Patent Document 1, the surface of the copper foil is polished with emery paper to form irregularities, aiming to improve adhesion.

Japanese Patent No. 3733067

  However, as described in Patent Document 1, even if the copper foil is simply polished by polishing paper such as emery paper, unevenness is formed even when the current collector copper foil and the active material have sufficient adhesion. There was a problem that it could not be obtained.

  Moreover, when the roughening process layer by roughening plating was provided in copper foil and the unevenness | corrugation was formed, there existed a problem that omission of the roughening particle | grains of a roughening particle layer would arise a lot.

  An object of the present invention is to provide a surface-treated copper foil for a battery in which roughened particles are less dropped and good adhesion to an active material can be obtained.

  The present inventors diligently studied the reason why sufficient adhesion could not be obtained in the prior art, and the roughened particles formed on the copper foil surface by the roughening treatment using a copper sulfate plating bath were enlarged. We found the problem of non-uniformity due to the accumulation of roughened particles. That is, there is a problem that sufficient adhesion between the current collector copper foil and the active material cannot be obtained because the roughened particles fall off as copper powder from the portion where the roughened particles are stacked. Therefore, the present inventors control the ten-point average roughness Rz of the surface treatment layer obtained by forming the primary particle layer and the secondary particle layer on the surface side of the copper foil, thereby adhering to the active material. It was found that the property is good. And this invention is completed based on the said knowledge.

  That is, the present invention is a copper foil and a surface-treated copper foil for a battery having a surface treatment layer on at least one surface side of the copper foil, wherein the surface treatment layer is a primary particle layer or a secondary particle layer. In this order from the surface side of the copper foil, and the surface-treated layer surface of the surface-treated copper foil for batteries was measured using a laser microscope with a wavelength of 405 nm in accordance with JIS B0601 1994. This is a surface-treated copper foil for a battery having a thickness Rz of 1.8 μm or more.

  Moreover, in one Embodiment of this invention, arithmetic mean roughness Ra when the surface treatment layer surface of the said surface treatment copper foil for batteries is measured using the laser microscope of wavelength 405nm based on JISB06011994 is 0. .26 μm or more.

  In one embodiment of the present invention, the primary particle layer includes one or more selected from the group consisting of Cu, W, Ti, As, V, Mo, Ni, Co, Cr, Zn, P, and Sn.

  In one embodiment of the present invention, the secondary particle layer includes one or more selected from the group consisting of Cu, W, Ti, As, V, Mo, Ni, Co, Cr, Zn, P, and Sn. .

In one embodiment of the present invention, the surface treatment layer includes a total of 100 μg of at least one selected from the group consisting of Cu, W, Ti, As, V, Mo, Ni, Co, Cr, Zn, P, and Sn. / Dm ² or more.

In one embodiment of the present invention, the surface treatment layer includes a total of 10,000 μg of at least one selected from the group consisting of Cu, W, Ti, As, V, Mo, Ni, Co, Cr, Zn, P, and Sn. / Dm ² or less.

Moreover, in one Embodiment of this invention, the said surface treatment layer contains Ni, and the adhesion amount of Ni is 100 microgram / dm < ² > or more.

Moreover, in one Embodiment of this invention, the said surface treatment layer contains Ni and the adhesion amount of Ni is 4500 microgram / dm < ² > or less.

Moreover, in one Embodiment of this invention, the said surface treatment layer contains Co, and the adhesion amount of Co is 100 microgram / dm < ² > or more.

Moreover, in one Embodiment of this invention, the said surface treatment layer contains Co, and the adhesion amount of Co is 6000 microgram / dm < ² > or less.

  Moreover, in one Embodiment of this invention, the said primary particle layer consists of Cu.

  Moreover, in one Embodiment of this invention, the said secondary particle layer consists of Cu, Co, and Ni.

  In one embodiment of the present invention, the copper foil is made of In, Au, Pd, Ag, Cr, Fe, P, Ti, Sn, Zn, Mn, Mo, Co, Ni, Si, Zr, B, and Mg. 1 type or more selected from the group which consists of 5 mass ppm or more and 0.3 mass% or less is included in total.

  In one embodiment of the present invention, the copper foil is made of In, Au, Pd, Ag, Cr, Fe, P, Ti, Sn, Zn, Mn, Mo, Co, Ni, Si, Zr, B, and Mg. 1 type or more selected from the group which consists of 5 mass ppm or more and 300 mass ppm or less is included in total.

  In one embodiment of the present invention, the copper foil is made of In, Au, Pd, Ag, Cr, Fe, P, Ti, Sn, Zn, Mn, Mo, Co, Ni, Si, Zr, B, and Mg. 1 type or more selected from the group which consists of 301 mass ppm or more and 0.3 mass% or less in total is included.

  In one embodiment of the present invention, the surface treatment layer further comprises a heat-resistant layer, a rust prevention layer, a chromate treatment layer, a silane coupling treatment layer, a plating layer, and a resin layer on the secondary particle layer. One or more layers selected from:

  Moreover, in one Embodiment of this invention, the surface-treated copper foil for batteries of this invention is for secondary batteries.

  Moreover, in one Embodiment of this invention, the surface-treated copper foil for batteries of this invention is an object for secondary battery collectors.

  Moreover, this invention is a collector which has the above-mentioned surface-treated copper foil for batteries.

  Moreover, this invention is an electrode which has the above-mentioned surface-treated copper foil for batteries.

  Moreover, this invention is a battery which has the above-mentioned surface-treated copper foil for batteries, or a collector or an electrode.

  According to the present invention, it is possible to obtain a surface-treated copper foil for a battery with less dropout of roughened particles and good adhesion to an active material. Moreover, according to some embodiments of the present invention, it is possible to obtain a surface-treated copper foil for a battery provided with a surface treatment having further excellent heat resistance characteristics.

It is a conceptual diagram which shows the mode of the roughening particle | grains at the time of performing the conventional roughening process on the surface of copper foil. It is a conceptual diagram which shows the mode of the surface treatment layer of the surface treatment copper foil for batteries which has the surface treatment layer of this invention.

<Surface-treated copper foil for batteries>
The surface-treated copper foil for a battery of the present invention (including a copper alloy foil) is prepared, for example, by forming an active material thin film thereon as a current collector of a battery or a secondary battery, and finally producing this electrode. Can be produced as a battery or a secondary battery. A method for forming the active material thin film on the current collector is not particularly limited. For example, a CVD method, a sputtering method, a vapor deposition method, a thermal spraying method, a liquid containing an active material is applied on the current collector, and The method of drying after that or the plating method etc. are mentioned. Among these thin film forming methods, the CVD method, the sputtering method, and the vapor deposition method are particularly preferably used. Further, an intermediate layer may be formed on the current collector, and an active material thin film may be formed on the intermediate layer. The surface-treated copper foil for batteries of the present invention can be used for known electrodes, known current collectors, and known batteries. Known batteries include, for example, lithium ion secondary batteries, all solid state secondary batteries, air batteries (lithium-air batteries, zinc-air batteries, etc.), sodium ion batteries, magnesium ion batteries, polyvalent ion batteries, and sulfur-based positive electrodes. Secondary batteries using substances, secondary batteries using an organic substance exhibiting redox activity on the positive electrode, nickel / cadmium batteries, manganese batteries (dry batteries), alkaline batteries (dry batteries), lithium batteries (dry batteries), and the like. Examples of known electrodes and known current collectors include electrodes and current collectors used in the aforementioned known batteries.

<Copper foil>
There is no restriction | limiting in particular in the form of the copper foil which can be used for this invention, A well-known copper foil can be used. Typically, the copper foil used in the present invention may be a copper foil formed by dry plating or wet plating, an electrolytic copper foil, or a rolled copper foil. In general, the electrolytic copper foil is produced by electrolytically depositing copper on a titanium or stainless steel drum from a copper sulfate plating bath. Moreover, a rolled copper foil is manufactured by repeating plastic working and heat treatment with a rolling roll. Rolled copper foil is often used for applications that require flexibility. When using the above-mentioned copper foil, for example, rolled copper foil, after manufacturing copper foil after rolling etc., the copper foil which annealed (annealed) can also be used. A rolled copper foil subjected to an annealing treatment is preferable because the bending resistance and the like are improved.
Copper foil materials include tough pitch copper (JIS H3100 alloy number C1100), oxygen-free copper (JIS H3100 alloy number C1020 or JIS H3510 alloy number C1011), phosphorous deoxidized copper (JIS H3100 alloy number C1201, C1220 or C1221), and electric copper. In addition to high-purity copper, for example, Sn-containing copper, Ag-containing copper, the above-described high-purity copper, In, Au, Pd, Ag, Cr, Fe, P, Ti, Sn, Zn, Mn, Mo, Co, Copper alloys such as a copper alloy added with one or more selected from the group consisting of Ni, Si, Zr, B and / or Mg, and a Corson copper alloy added with Ni, Si and the like can also be used. Moreover, the copper foil and copper alloy foil which have a well-known composition can also be used. In addition, when the term “copper foil” is used alone in this specification, a copper alloy foil is also included. As the copper foil material, the above-described high-purity copper is made of In, Au, Pd, Ag, Cr, Fe, P, Ti, Sn, Zn, Mn, Mo, Co, Ni, Si, Zr, B, and Mg. One or more selected from the group consisting of 5 mass ppm or more, preferably 10 mass ppm or more, preferably 15 mass ppm or more, preferably 20 mass ppm or more, preferably 25 mass ppm or more, preferably 30 mass ppm or more. , Preferably 35 mass ppm or more, preferably 40 mass ppm or more, preferably 45 mass ppm or more, preferably 50 mass ppm or more, preferably 301 mass ppm or more, preferably 310 mass ppm or more, preferably 350 mass ppm or more, Preferably 380 ppm by mass or more, preferably 400 ppm by mass or more, preferably 500 ppm by mass or more It is also possible to use a copper alloy. As the copper foil material, the above-described high-purity copper is made of In, Au, Pd, Ag, Cr, Fe, P, Ti, Sn, Zn, Mn, Mo, Co, Ni, Si, Zr, B, and Mg. One or more selected from the group consisting of 50% by mass or less, preferably 40% by mass or less, preferably 30% by mass or less, preferably 20% by mass or less, preferably 10% by mass or less, preferably 5% by mass or less. 1 mass% or less, preferably 0.8 mass% or less, preferably 0.6 mass% or less, preferably 0.5 mass% or less, preferably 0.3 mass% or less, preferably 0.28 mass%. % Or less, preferably 0.25 mass% or less, preferably 0.23 mass% or less, preferably 0.20 mass% or less, preferably 0.17 mass% or less, preferably 0.15 mass% or less, preferably 300 mass p m it is possible to use the added copper alloy below. Selected from the group consisting of In, Au, Pd, Ag, Cr, Fe, P, Ti, Sn, Zn, Mn, Mo, Co, Ni, Si, Zr, B and Mg added to the above-described high purity copper When the total concentration of one or more elements is high (for example, 301 mass ppm or more), the strength of the copper foil becomes higher, which is effective. Also, the sum of one or more elements selected from the group consisting of In, Au, Pd, Ag, Cr, Fe, P, Ti, Sn, Zn, Mn, Mo, Co, Ni, Si, Zr, B, and Mg When the concentration of is low (for example, 300 mass ppm or less), it is effective because it has excellent flexibility.

<Surface treatment layer>
The surface treatment layer has a primary particle layer and a secondary particle layer in this order from the copper foil side. The surface treatment layer has a primary particle layer and a secondary particle layer in this order from the copper foil side, so that powder falling due to falling off of the roughened particles is reduced. Moreover, the surface treatment layer has an effect that the adhesion between the copper foil and the active material is improved by having the primary particle layer and the secondary particle layer in this order from the copper foil side. This is presumably because the roughened particles are less likely to break by providing the primary particle layer and the secondary particle layer. Moreover, the surface treatment layer has a primary particle layer and a secondary particle layer in this order from the copper foil side, whereby the heat resistance of the copper foil is improved. The primary particle layer and the secondary particle layer can be formed by an electroplating layer. The secondary particles are characterized by one or more particles grown on the primary particles. Alternatively, the secondary particle layer is a normal plating layer grown on the primary particles. The secondary particles may have a dendritic shape. That is, in the present specification, when the term “secondary particle layer” is used, a normal plating layer such as overlay plating is also included. Further, the secondary particle layer may be a layer having one or more layers formed of roughened particles, or may be a layer having one or more normal plating layers, and is normal with a layer formed of roughened particles. A layer having one or more plating layers may be used. The surface treatment layer may have one or a plurality of other layers other than the primary particle layer and the secondary particle layer. In addition, normal plating means plating performed under conditions of current density equal to or lower than the limit current density.
The primary particle layer is a roughened particle directly formed on the copper foil and a roughened particle stacked on the roughened particle, and is directly formed on the copper foil. A layer containing roughened particles having the same composition as the roughened particles or having the same elements as the elements contained in the roughened particles directly formed on the copper foil is used. The secondary particle layer is a roughened particle formed on the roughened particles contained in the primary particle layer and has a composition different from that of the roughened particles forming the primary particle layer or the primary particles. A layer containing roughened particles containing an element not included in the roughened particles forming the layer is used.
Further, when the presence or absence of the elements constituting the primary particles and / or the secondary particles and / or the concentration or adhesion amount of the elements cannot be measured, the primary particles and the secondary particles are scanned, for example. When observed with a scanning electron micrograph, particles that appear to overlap and exist on the copper foil side (downward), and non-overlapping particles are primary particles that appear to overlap and other particles The particles present above can be determined as secondary particles. In addition, when the base plating layer (normal plating layer) such as copper is provided on the copper foil, the above-mentioned “roughened particles directly formed on the copper foil” It also includes roughened particles that are formed directly on the surface.

The surface-treated copper foil for a battery of the present invention has a 10-point average roughness Rz of 1.8 μm or more when the surface treatment layer surface is measured using a laser microscope with a wavelength of 405 nm in accordance with JIS B0601 1994. If Rz is less than 1.8 μm, as shown in the conceptual diagram of FIG. 1, the roughened particles on the copper foil are distributed in the shape of elongated dendrites. Since it is easy to break or falls off from the root, adhesion to the active material is not good. On the other hand, when Rz is 1.8 μm or more, as shown in the conceptual diagram of FIG. 2, sharp rising does not occur and rounded particles grow, so that the branches are difficult to break and fall off from the root. As a result, the adhesion with the active material is improved. In this respect, the ten-point average roughness Rz is more preferably 1.9 μm or more, more preferably 2.0 μm or more, still more preferably 2.1 μm or more, still more preferably 2.2 μm or more, and even more preferably It is 2.3 μm or more, and more preferably 2.35 μm or more. The upper limit of the ten-point average roughness Rz is not particularly limited, but is typically, for example, 10 μm or less, preferably 8 μm or less, more preferably 5 μm or less, more preferably 3.30 μm or less, and further preferably 3.20 μm. Or less, more preferably 3.10 μm or less, more preferably 3.05 μm or less, further preferably 3 μm or less, further preferably 2.95 μm or less, more preferably 2.90 μm or less, still more preferably 2.85 μm or less, and further preferably Is 2.80 μm or less. When Rz is small to some extent such as 3 μm or less, it is presumed that the roughened particles are more difficult to fall off and the adhesion to the active material is better. In addition, when the surface treatment layer exists on both surfaces of the copper foil, the effect of the present invention is exhibited if one of the ten-point average roughness Rz is within the above range. Therefore, the one ten-point average roughness Rz is within the above range. The ten-point average roughness Rz may be within the above range.
In addition, the above-mentioned “surface treatment layer surface” means that the surface treatment copper foil for the battery includes a primary particle layer, a secondary particle layer, a heat-resistant layer, a rust prevention tank, a chromate treatment layer, a silane coupling treatment layer, a plating layer, and the like. In the case of having a plurality of layers, it means the surface of the outermost layer of the plurality of layers.

  From the same viewpoint, the surface-treated copper foil for a battery of the present invention has an arithmetic average roughness Ra when the surface-treated layer surface is measured using a laser microscope with a wavelength of 405 nm in accordance with JIS B0601 1994. The thickness is preferably 0.26 μm or more. The arithmetic average roughness Ra is more preferably 0.28 μm or more, more preferably 0.30 μm or more, more preferably 0.32 μm or more, more preferably 0.34 μm or more, more preferably 0.36 μm or more, more preferably Is 0.38 μm or more, still more preferably 0.40 μm or more. The upper limit of the arithmetic average roughness Ra is not particularly limited, but typically, for example, 5.0 μm or less, preferably 4.5 μm or less, more preferably 4.0 μm or less, more preferably 3.5 μm or less, Preferably it is 3.0 μm or less, more preferably 2.5 μm or less, more preferably 2.0 μm or less, more preferably 1.5 μm or less, more preferably 1.0 μm or less, more preferably 0.5 μm or less, and further preferably It is 0.45 μm or less, more preferably 0.44 μm or less, further preferably 0.41 μm or less, and further preferably 0.40 μm or less. In addition, when the surface treatment layer exists on both surfaces of the copper foil, the effect of the present invention is exhibited if one arithmetic average roughness Ra is within the above range, so that one arithmetic average roughness Ra is within the above range. Both arithmetic mean roughness Ra may be within the above range.

The average particle diameter of the primary particle layer is preferably 0.1 to 0.6 μm. Moreover, it is preferable that the average particle diameter of a secondary particle layer shall be 0.01-0.45 micrometer. Here, the particle diameter means the diameter of the smallest circle surrounding the particles when the roughened particles are observed by taking a photograph from directly above the copper foil with a scanning electron microscope. Moreover, an average particle diameter means the arithmetic mean value of the particle diameter of several roughening particle | grains. Specifically, the average particle diameter of the primary particle layer is the arithmetic average of the particle diameters of the coarse particles of the primary particle layer present in the region of 4 μm wide × 3 μm long in the photograph taken with the scanning electron microscope. Mean value. The average particle size of the secondary particle layer is the arithmetic average value of the particle size of the coarse particles of the secondary particle layer existing in the region of 4 μm wide × 3 μm long in the photograph taken with the scanning electron microscope. Means.
The average particle size of the primary particle layer is such that when the primary particle layer is formed, the concentration of the element attached to the copper foil by plating in the plating solution used is lowered and / or the current density is increased. It can be increased by increasing the surface treatment time (energization time during plating) and / or increasing the number of times of plating. The average particle size of the primary particle layer is such that when forming the primary particle layer, the concentration of the element attached to the copper foil by plating in the plating solution used is increased and / or the current density is decreased. Or / and shortening the surface treatment time (energization time for plating) and / or reducing the number of times of plating.
In addition, the average particle diameter of the secondary particle layer is determined by reducing the concentration of the element attached to the copper foil by plating in the plating solution used when forming the secondary particle layer, and / or the current density. Can be increased by increasing the surface treatment time (or energizing time during plating) and / or increasing the number of times of plating. The average particle size of the secondary particle layer is determined by increasing the concentration of elements attached to the copper foil by plating in the plating solution used when forming the secondary particle layer and / or current density. And / or shortening the surface treatment time (energization time for plating) and / or reducing the number of times of plating.

In the surface-treated copper foil for a battery of the present invention, the primary particle layer in the surface-treated layer is a kind selected from the group consisting of Cu, W, Ti, As, V, Mo, Ni, Co, Cr, Zn, P, and Sn. Or it can have 2 or more types of elements. The primary particle layer in the surface treatment layer preferably has one or more elements selected from the group consisting of Cu, W, Ti, As, Cr and P. The primary particle layer in the surface treatment layer preferably has one or more elements selected from the group consisting of Cu, W, As and P. This is because it becomes easier to prevent powder falling. The secondary particle layer also has one or more elements selected from the group consisting of Cu, W, Ti, As, V, Mo, Ni, Co, Cr, Zn, P and Sn. it can. And one or more elements selected from the group consisting of Cu, W, Ti, As, V, Mo, Ni, Co, Cr, Zn, P and Sn contained in the primary particle layer and the secondary particle layer. The total adhesion amount can be, for example, 100 μg / dm ² or more. The upper limit of the total adhesion amount is not particularly limited, but can be, for example, 10,000 μg / dm ² or less. One or more selected from the group consisting of Cu, W, Ti, As, V, Mo, Ni, Co, Cr, Zn, P, and Sn contained in the primary particle layer and the secondary particle layer described above. The total adhesion amount of these elements can be, for example, 100 μg / dm ² or more. The upper limit of the total adhesion amount is not particularly limited, but can be, for example, 10,000 μg / dm ² or less.

  From the viewpoint of improving battery capacity, electrode active materials have been studied from simple carbon-based active materials to silicon-based and composite active materials in which a plurality of types are mixed. When such a silicon-based active material is used, a polyimide-based binder may be used, and heating at 300 ° C. or higher is required for bonding. Therefore, if the adhesiveness with the active material is good, the object of the present invention can be achieved, but for a secondary battery current collector that has a heat resistance property that does not cause oxidation discoloration of the copper foil surface even after heating at 300 ° C. or higher. More preferably, it is a copper foil. Select one or more elements from the group consisting of Cu, W, Ti, As, V, Mo, Ni, Co, Cr, Zn, P and Sn, and form a secondary particle layer according to the amount of adhesion. By doing so, the above heat resistance characteristics can be improved.

The surface treatment layer of the surface-treated copper foil for a battery of the present invention may not contain Ni or the surface treatment layer may contain Ni. When the surface treatment layer contains Ni, the adhesion amount of Ni in the surface treatment layer is preferably 100 μg / dm ² or more. When the adhesion amount of Ni is less than 100 μg / dm ² , there may be a problem that the heat resistance is remarkably deteriorated. When the surface treatment layer contains Ni, the adhesion amount of Ni in the surface treatment layer is preferably 4500 μg / dm ² or less. If it exceeds 4500 μg / dm ² , the Ni film thickness is increased, so that there is a possibility that the electrical resistance value increases and the electrical characteristics of the current collector copper foil deteriorate. The adhesion amount of Ni is more preferably 200 μg / dm ² or more, still more preferably 300 μg / dm ² or more, and even more preferably 400 μg / dm ² or more. The coating weight of the Ni is more preferably 4400μg / dm ² or less, still more preferably from 4300μg / dm ² or less, even more preferably 4200μg / dm ² or less, even more preferably 4100μg / dm ² or less, even more Preferably it is 4000 μg / dm ² or less, and more preferably 3950 μg / dm ² or less. In addition, when a surface treatment layer contains Ni, there exists a case where there exists an effect that the chemical resistance of a surface treatment copper foil improves compared with the case where it does not contain Ni.

The surface treatment layer of the surface-treated copper foil for a battery of the present invention may not contain Co, or the surface treatment layer may contain Co. When the surface treatment layer contains Co, the amount of Co deposited on the surface treatment layer is preferably 100 μg / dm ² or more. When the adhesion amount of Co is less than 100 μg / dm ² , there may be a problem that heat resistance is remarkably deteriorated. When the surface treatment layer contains Co, the amount of Co deposited on the surface treatment layer is preferably 6000 μg / dm ² or less. If it exceeds 6000 μg / dm ² , the Co film thickness is increased, and thus magnetism is exhibited, which may cause a problem that the electrical characteristics are inferior as a copper foil for a battery, particularly as a copper foil for a current collector. The adhesion amount of Co is more preferably 200 μg / dm ² or more, more preferably 300 μg / dm ² or more, more preferably 400 μg / dm ² or more, more preferably 500 μg / dm ² or more, more preferably 600 μg / dm ^2. or more, more preferably 700 [mu] g / dm ² or more, more preferably 800 [mu] g / dm ² or more, more preferably 900 [mu] g / dm ² or more, more preferably 1000 [mu] g / dm ² or more. Further, the adhesion amount of the Co is more preferably 5500μg / dm ² or less, more preferably 5000 [mu] g / dm ² or less, more preferably 4500μg / dm ² or less, more preferably 4300μg / dm ² or less, more preferably 4200Myug / dm ² or less, more preferably 4100 μg / dm ² or less, more preferably 4000 μg / dm ² or less, more preferably 3950 μg / dm ² or less. In addition, when a surface treatment layer contains Co, there exists a case where there exists an effect that the weather resistance of a surface treatment copper foil improves compared with the case where Co is not contained.

  In the present invention, the adhesion amount of elements such as Cu, W, Ti, As, V, Mo, Ni, Co, Cr, Zn, Sn, and P in the surface treatment layer is defined. It defines the total amount of attached elements present in the surface treatment layer including the secondary particle layer. Moreover, when these surface treatment layers exist in both surfaces of copper foil, it is prescription | regulation in the surface treatment layer of one surface, and the element contained in the surface treatment layer formed in both surfaces (for example, It is not the total value of Ni and the like.

  The surface treatment layer of the surface-treated copper foil for a battery of the present invention has an adhesion amount of elements such as Cu, W, Ti, As, V, Mo, Ni, Co, Cr, Zn, Sn, and P within the above range. For example, the type and amount of adhesion can be changed as necessary, but the primary particle layer is preferably made of Cu from the viewpoint of further improving the adhesion to the active material thin film. Here, “the primary particle layer is made of Cu” is a concept including “the primary particle layer contains only Cu” and “the primary particle layer contains only Cu and inevitable impurities”. Moreover, it is preferable that a secondary particle layer consists of Cu, Co, and Ni from a viewpoint of improving the heat resistance of surface-treated copper foil. Here, “the secondary particle layer is made of Cu, Co, Ni” means “the secondary particle layer contains only Cu, Co and Ni” and “the secondary particle layer is Cu, Co and Ni”. And “contains only inevitable impurities”.

  In addition, the adhesion amount of the element contained in the surface treatment layer is to increase the concentration of the element in the surface treatment liquid used when forming the surface treatment layer and / or when the surface treatment is plating. It can be increased by increasing the current density and / or increasing the surface treatment time (the energization time during plating). In addition, the adhesion amount of the element contained in the surface treatment layer is such that the concentration of the element in the surface treatment liquid used when forming the surface treatment layer is lowered and / or when the surface treatment is plating. It can be reduced by reducing the current density and / or shortening the surface treatment time (energization time for plating).

<Formation conditions of primary particle layer and secondary particle layer>
The surface treatment layer of the surface-treated copper foil for a battery according to the present invention sequentially forms a primary particle layer and a secondary particle layer from the surface side of the copper foil. The primary particle layer and the secondary particle layer may be formed directly from the surface side of the copper foil. The base plating layer is formed on the surface side of the copper foil, and then the primary particle layer and the secondary particle layer are formed in order. May be. The aforementioned base plating layer may be a Cu plating layer. The formation conditions of the primary particle layer and the secondary particle layer are shown below, but this is only a preferable example, and the surface treatment layer surface is compliant with JIS B0601 1994 using a laser microscope with a wavelength of 405 nm. If the ten-point average roughness Rz when measured is 1.8 μm or more, it does not disturb the plating conditions other than those indicated below.
In addition, 10-point average roughness Rz when the surface treatment layer surface is measured using a laser microscope having a wavelength of 405 nm in accordance with JIS B0601 1994 forms a primary particle layer and / or a secondary particle layer. In the plating solution to be used, the concentration of the element attached to the copper foil by plating is lowered and / or the current density is increased and / or the surface treatment time (the energization during plating) The time can be increased by increasing the time) and / or increasing the number of times of plating. The 10-point average roughness Rz when the surface treatment layer surface is measured using a laser microscope having a wavelength of 405 nm in accordance with JIS B0601 1994 forms a primary particle layer and / or a secondary particle layer. In the surface treatment solution used, the concentration of the element attached to the copper foil by plating is increased and / or the current density is decreased and / or the surface treatment time (when plating is performed) The energization time can be shortened by shortening.
Further, the arithmetic average roughness Ra when the surface treatment layer surface is measured using a laser microscope with a wavelength of 405 nm in accordance with JIS B0601 1994 is used when forming the primary particle layer and / or the secondary particle layer. In addition, in the plating solution to be used, the concentration of the element adhering to the copper foil due to the plating is lowered and / or the current density is increased, and / or the surface treatment time (the energization time during plating) ) Can be increased by making it longer. Further, the arithmetic average roughness Ra when the surface treatment layer surface is measured using a laser microscope with a wavelength of 405 nm in accordance with JIS B0601 1994 is used when forming the primary particle layer and / or the secondary particle layer. In addition, in the plating solution used, the concentration of the element attached to the copper foil by plating is increased and / or the current density is decreased, and / or the surface treatment time (the energization time during plating) ) Can be shortened and / or the number of times of plating can be reduced.

-Primary particle layer After processing with a primary particle plating solution (A), when processing with a primary particle plating solution (B), it is possible to form a primary particle layer on the following conditions.
(Treatment with primary particle plating solution (A))
<Electrolyte composition>
Copper: 5-15g / L
Sulfuric acid: 70-80g / L
<Production conditions>
Current density: 40-60 A / dm ²
Electrolyte temperature: 25-35 ° C
Electrolysis time: 0.5 to 1.6 seconds (treatment with primary particle plating solution (B))
<Electrolyte composition>
Copper: 20-50 g / L
Sulfuric acid: 60-100 g / L
<Production conditions>
Current density: 4 to 10 A / dm ²
Electrolyte temperature: 35-55 ° C
Electrolysis time: 1.4 to 2.5 seconds

When the primary particle layer is formed only by the treatment with the primary particle plating solution (I), it is carried out under the conditions described in the following treatment 1 with the primary particle plating solution (I) or treatment 2 with the primary particle plating solution (I). It is possible.
(Treatment with primary particle plating solution (I) 1)
<Electrolyte composition>
Copper: 10-45 g / L
Cobalt: 5-30 g / L
Nickel: 5-30g / L
pH: 2.8-3.2
<Production conditions>
Current density: 30 to 45 A / dm ²
Electrolyte temperature: 30-40 ° C
Electrolysis time: 0.3 to 0.8 seconds

(Treatment with primary particle plating solution (I) 2)
<Electrolyte composition>
Copper: 5-15g / L
Nickel: 3-30g / L
pH: 2.6-3.0
<Production conditions>
Current density: 50 to 70 A / dm ²
Electrolyte temperature: 30-40 ° C
Electrolysis time: 0.3 to 0.9 seconds

-Secondary particle layer When forming a secondary particle layer, it is possible to implement by the process by the following secondary particle plating solution (I) or secondary particle plating solution (II).
(Treatment with secondary particle plating solution (I))
<Electrolyte composition>
Copper: 10-15g / L
Cobalt: 5-15g / L
Nickel: 5-15g / L
pH: 2.8-3.2
<Production conditions>
Current density: 20 to 40 A / dm ²
Electrolyte temperature: 33-37 ° C
Electrolysis time: 0.5 to 1.0 seconds

(Treatment with secondary particle plating solution (II))
<Electrolyte composition>
Copper: 5-12g / L
Nickel: 2-11g / L
pH: 2.8
<Production conditions>
Current density: 55 to 65 A / dm ²
Electrolyte temperature: 35-40 ° C
Electrolysis time: 0.3 to 0.9 seconds

<Cover plating>
Cover plating can be performed on the secondary particle layer. The effect of improving heat resistance can be expected by forming the cover plating. The layer formed by covering plating is, for example, a Zn—Cr alloy layer, a Ni—Mo alloy layer, a Zn layer, a Co—Mo alloy layer, a Co—Ni alloy layer, a Ni—W alloy layer, a Ni—Zn alloy layer, Ni -P alloy layer, Ni-Fe alloy layer, Ni-Al alloy layer, Co-Zn alloy layer, Co-P alloy layer, Zn-Co alloy layer, Ni layer, Co layer, Cr layer, Al layer, Sn layer, Zn, Cr, Ni, Fe, Ta, Cu, Al, P, W, Mn, Sn, As, Ti, Mo, Co, etc., such as Sn—Ni layer, Ni—Sn layer or Zn—Ni alloy layer A metal layer composed of one element selected from the group consisting of: or a group consisting of Zn, Cr, Ni, Fe, Ta, Cu, Al, P, W, Mn, Sn, As, Ti, Mo and Co Alloy layer containing 2 or 3 or more selected elements or the aforementioned element group Alloy layer can be mentioned consists of two or more elements selected.
The cover plating can be performed by performing a treatment with the following cover plating solution or a combination thereof. In addition, the metal layer and / or the alloy layer that cannot be provided by wet plating can be provided by a dry plating method such as sputtering, physical vapor deposition (PVD), or chemical vapor deposition (CVD).

・ Treatment with cover plating solution (1) Zn-Cr
Liquid composition: potassium dichromate 1-1 g / L, Zn 0.1-5 g / L
Liquid temperature: 40-60 degreeC
pH: 0.5-10
Current density: 0.01 to 2.6 A / dm ²
Energizing time: 0.05-30 seconds

・ Treatment with cover plating solution (2) Ni-Mo
Liquid composition: nickel sulfate 270-280 g / L, nickel chloride 35-45 g / L, nickel acetate 10-20 g / L, sodium molybdate 1-60 g / L, trisodium citrate 10-50 g / L, sodium dodecyl sulfate 50 ~ 90ppm
Liquid temperature: 20-65 degreeC
pH: 4-12
Current density: 0.5 to 5 A / dm ²
Energizing time: 0.1 to 5 seconds

・ Treatment with cover plating solution (3) Zn
Liquid composition: Zn1-15g / L
Liquid temperature: 25-50 degreeC
pH: 2-6
Current density: 0.5 to 5 A / dm ²
Energizing time: 0.01 to 0.3 seconds

・ Treatment with cover plating solution (4) Co-Mo
Liquid composition: Co 1-20 g / L, sodium molybdate 1-60 g / L, sodium citrate 10-110 g / L
Liquid temperature: 25-50 degreeC
pH: 5-7
Current density: 1-4 A / dm ²
Energizing time: 0.1 to 5 seconds

・ Treatment with cover plating solution (5) Co-Ni
Liquid composition: Co1-20g / L, N1-20g / L
Liquid temperature: 30-80 degreeC
pH: 1.5-3.5
Current density: 1 to 20 A / dm ²
Energizing time: 0.1 to 4 seconds

・ Treatment with cover plating solution (6) Zn-Ni
Liquid composition: Zn1-30 g / L, N1-30 g / L
Liquid temperature: 40-50 degreeC
pH: 2-5
Current density: 0.5 to 5 A / dm ²
Energizing time: 0.01 to 0.3 seconds

・ Treatment with cover plating solution (7) Ni-W
Liquid composition: Ni1-30g / L, W1-300mg / L
Liquid temperature: 30-50 degreeC
pH: 2-5
Current density: 0.1 to 5 A / dm ²
Energizing time: 0.01 to 0.3 seconds

・ Treatment with cover plating solution (8) Ni-P
Liquid composition: Ni1-30g / L, P1-10g / L
Liquid temperature: 30-50 degreeC
pH: 2-5
Current density: 0.1 to 5 A / dm ²
Energizing time: 0.01 to 0.3 seconds

<Other surface treatment>
In addition, the surface treatment layer of the surface-treated copper foil for a battery according to the present invention is further provided with a heat-resistant layer, a rust prevention layer, a chromate treatment layer, a silane coupling treatment layer, a plating layer on the secondary particle layer or the above-mentioned covering plating layer. One or more layers selected from the group consisting of resin layers may be included. The above heat-resistant layer, rust prevention layer, chromate treatment layer, silane coupling treatment layer, plating layer, and resin layer may each form a plurality of layers (for example, 2 layers or more, 3 layers or more, etc.).

As the heat-resistant layer and rust-proof layer, known heat-resistant layers and rust-proof layers can be used. For example, the heat-resistant layer and / or the anticorrosive layer is a group of nickel, zinc, tin, cobalt, molybdenum, copper, tungsten, phosphorus, arsenic, chromium, vanadium, titanium, aluminum, gold, silver, platinum group elements, iron, tantalum A layer containing one or more elements selected from nickel, zinc, tin, cobalt, molybdenum, copper, tungsten, phosphorus, arsenic, chromium, vanadium, titanium, aluminum, gold, silver, platinum group elements Further, it may be a metal layer or an alloy layer made of one or more elements selected from the group consisting of iron, tantalum and the like. Further, the heat-resistant layer and / or the rust-preventing layer may contain oxides, nitrides and silicides containing the above-mentioned elements. Further, the heat-resistant layer and / or the rust preventive layer may be a layer containing a nickel-zinc alloy. Further, the heat-resistant layer and / or the rust preventive layer may be a nickel-zinc alloy layer. The nickel-zinc alloy layer may contain 50 wt% to 99 wt% nickel and 50 wt% to 1 wt% zinc, excluding inevitable impurities. The total adhesion amount of zinc and nickel in the nickel-zinc alloy layer may be 5 to 1000 mg / m ² , preferably 10 to 500 mg / m ² , preferably 20 to 100 mg / m ² . Further, the ratio of the nickel adhesion amount and the zinc adhesion amount of the layer containing the nickel-zinc alloy or the nickel-zinc alloy layer (= nickel adhesion amount / zinc adhesion amount) is 1.5 to 10. It is preferable. Further, the nickel - in adhesion amount of nickel in the zinc alloy layer is preferably from ^{0.5mg / m 2 ~500mg / m 2} , 1mg / m 2 ~50mg / m 2 - zinc alloy layer or the nickel containing More preferably. When the heat-resistant layer and / or rust prevention layer is a layer containing a nickel-zinc alloy, the interface between the copper foil and the resin substrate is eroded by the desmear liquid when the inner wall such as a through hole or via hole comes into contact with the desmear liquid. It is difficult to improve the adhesion between the copper foil and the resin substrate.

For example heat-resistant layer and / or anticorrosive layer has coating weight of 1 mg / m ² -100 mg / m ^2, preferably from 5 mg / m ² and to 50 mg / m ² of nickel or nickel alloy layer, the adhesion amount is 1 mg / m ² to 80 mg / m ^2, preferably it may be obtained by sequentially laminating a tin layer of ^{5mg / m 2 ~40mg / m 2} , wherein the nickel alloy layer is a nickel - molybdenum alloy, nickel - zinc alloys, nickel - molybdenum -You may be comprised by either 1 type of a cobalt alloy and a nickel- tin alloy.

  In the present specification, the chromate-treated layer refers to a layer treated with a liquid containing chromic anhydride, chromic acid, dichromic acid, chromate or dichromate. Chromate treatment layer is any element such as Co, Fe, Ni, Mo, Zn, Ta, Cu, Al, P, W, Sn, As and Ti (metal, alloy, oxide, nitride, sulfide, etc.) May be included). Specific examples of the chromate treatment layer include a chromate treatment layer treated with chromic anhydride or a potassium dichromate aqueous solution, a chromate treatment layer treated with a treatment solution containing anhydrous chromic acid or potassium dichromate and zinc, and the like. .

  The silane coupling treatment layer may be formed using a known silane coupling agent, such as epoxy silane, amino silane, methacryloxy silane, mercapto silane, vinyl silane, imidazole silane, triazine silane. You may form using silane coupling agents, such as. In addition, you may use 2 or more types of such silane coupling agents in mixture. Especially, it is preferable to form using an amino-type silane coupling agent or an epoxy-type silane coupling agent.

  Further, on the surface of the copper foil, surface treatment layer, heat-resistant layer, rust prevention layer, silane coupling treatment layer or chromate treatment layer, for example, International Publication No. WO2008 / 053878, Japanese Patent Application Laid-Open No. 2008-111169, Japanese Patent No. 5024930, International The surface treatment described in publication number WO2006 / 028207, patent 4828427, international publication number WO2006 / 134868, patent 5046927, international publication number WO2007 / 105635, patent 5180815, and JP2013-19056A may be performed. it can.

Hereinafter, description will be made based on Examples and Comparative Examples. In addition, a present Example is an example to the last, and is not restrict | limited only to this example.
<Primary particle layer and secondary particle layer>
First, an ingot having a composition described in the column “Composition of copper foil substrate” in Table 1 was melted, and this ingot was hot-rolled from 900 ° C. to obtain a plate having a thickness of 10 mm. Then, cold rolling and annealing were repeated, and finally cold rolled to a copper foil having a thickness of 12 μm to obtain a rolled copper foil. Further, an HLP foil made by JX Metals Co., Ltd. having a thickness of 9 μm was prepared as the electrolytic copper foil of Example 7.
In Table 1, TPC in the “Composition of copper foil substrate” column represents tough pitch copper (JIS H3100 alloy number C1100), and OFC represents oxygen-free copper (JIS H3100 alloy number C1020). That is, for example, “190 ppm Ag-TPC” in Example 2 means that 190 mass ppm of Ag was added to tough pitch copper. For example, “1200 ppm Sn—OFC” in Example 4 means that 1200 mass ppm of Sn was added to oxygen-free copper.
Subsequently, after performing electrolytic degreasing, water washing, pickling on the surface of the rolled copper foil or the matte surface (deposition surface, M surface) side of the electrolytic copper foil, on the surface of each copper foil base material, A primary particle layer and / or a secondary particle layer was formed under the conditions shown in Table 1. Examples and comparative examples in which “Primary particle layer plating current condition A” and “Primary particle layer plating current condition B” are described in Table 1 are described in B after plating under the conditions described in A. It means that further plating was performed under the conditions. The plating solution conditions for forming the primary particle layer and the secondary particle layer are shown in the columns of “Primary particle layer plating solution A”, “Primary particle layer plating solution B”, and “Secondary particle layer plating solution” in Table 1 and below. . For example, when (1) is described in the “Primary particle layer plating solution A” column, the following “Priming solution condition in the primary particle layer A formation stage” “Plating solution (1)” is used as the primary. It means that the particle layer A was formed.
(Plating solution conditions at the primary particle layer A formation stage)
・ Plating solution (1)
Liquid composition: Copper 11g / L, sulfuric acid 50g / L
Liquid temperature: 25 ° C
pH: 1.0-2.0
・ Plating solution (2)
Liquid composition: Copper 11g / L, tungsten 3mg / L, sulfuric acid 50g / L
Liquid temperature: 25 ° C
pH: 1.0-2.0
・ Plating solution (3)
Liquid composition: Copper 11g / L, Arsenic 100mg / L, Sulfuric acid 50g / L
Liquid temperature: 25 ° C
pH: 1.0-2.0
・ Plating solution (4)
Liquid composition: Copper 11g / L, Titanium 6mg / L, Sulfuric acid 50g / L
Liquid temperature: 25 ° C
pH: 1.0-2.0
・ Plating solution (5)
Liquid composition: Copper 11g / L, chromium 3mg / L, sulfuric acid 50g / L
Liquid temperature: 25 ° C
pH: 1.0-2.0
(Plating solution conditions at the primary particle layer B formation stage)
・ Plating solution (1)
Liquid composition: Copper 22g / L, sulfuric acid 100g / L
Liquid temperature: 50 ° C
pH: 1.0-2.0
(Plating conditions at the secondary particle layer formation stage)
・ Plating solution (1)
Liquid composition: Copper 15g / L, nickel 8g / L, cobalt 8g / L
Liquid temperature: 36 ° C
pH: 2.7
・ Plating solution (2)
Liquid composition: Copper 15g / L, nickel 8g / L, phosphorus 1g / L
Liquid temperature: 36 ° C
pH: 2-3
・ Plating solution (3)
Liquid composition: Copper 15g / L, nickel 8g / L, cobalt 8g / L, molybdenum 8g / L
Liquid temperature: 36 ° C
pH: 2-3
・ Plating solution (4)
Liquid composition: Copper 15g / L, nickel 8g / L, tungsten 3g / L
Liquid temperature: 36 ° C
pH: 2-3
・ Plating solution (5)
Liquid composition: Copper 15g / L, Molybdenum 8g / L, Cobalt 8g / L
Liquid temperature: 36 ° C
pH: 2-3
<Cover plating>
Subsequently, the cover plating shown in Table 1 is formed on the primary particle layer when the primary particle layer is formed, and on the secondary particle layer when the primary particle layer and the secondary particle layer are formed. did. Each specific condition is described below.
(1) Ni layer Plating solution composition: Ni 10 g / L
pH: 2.5
Temperature: 50 ° C
Current density Dk: 12 A / dm ²
Plating time: 0.5 seconds Plating times: 2 times (2) Ni—Co alloy layer Plating bath composition: Ni 10 g / L, Co 5 g / L
pH: 2.5
Temperature: 50 ° C
Current density Dk: 10 A / dm ²
Plating time: 0.5 seconds Plating times: 2 times (3) Ni—Zn alloy layer Plating bath composition: Ni 10 g / L, Zn 5 g / L
pH: 3.5
Temperature: 40 ° C
Current density Dk: 2 A / dm ²
Plating time: 1 second Plating frequency: 2 times <Electrolytic chromate treatment>
After the above-described cover plating was formed, in Examples 1 to 7 and Comparative Examples 2 and 3, the following electrolytic chromate treatment was performed.
Liquid composition: potassium dichromate 3 g / L, Zn 0.5 g / L
Liquid temperature: 40-60 degreeC
pH: 4.0
Current density Dk: 2.0 A / dm ²
Plating time: 0.6 seconds Plating times: 2 times <Silane coupling treatment>
In Examples 1 to 7 and Comparative Examples 2 and 3, after the electrolytic chromate treatment, the following silane coupling treatment was further performed.
Silane coupling agent: N-2- (aminoethyl) -3-aminopropyltrimethoxysilane Silane coupling agent concentration: 1.0 vol%
Processing temperature: 25 ° C
Processing time: 3 seconds

In Comparative Example 4, as shown in Table 1, instead of forming the primary particle layer and the secondary particle layer under the predetermined conditions, the surface temper-rolled with a rolling roll having a roughened surface was used in an atmospheric atmosphere. Thermal oxidation treatment was performed, and then heat reduction treatment was performed in a nitrogen atmosphere containing 1% CO.
In Comparative Example 5, as shown in Table 1, instead of forming the primary particle layer and the secondary particle layer under the predetermined conditions, the first Cu plating, the second Cu plating, and the third Cu plating were sequentially performed under the following conditions. gave.
(First Cu plating conditions)
Plating bath composition: Cu 150 g / L to 250 g / L, sulfuric acid 100 g / L
pH: 1.0
Temperature: 40 ° C
Current density Dk: 5 A / dm ²
Plating time: 7 seconds Plating frequency: 1 time (2nd Cu plating condition)
Plating bath composition: Cu 50 g / L to 150 g / L, sulfuric acid 130 g / L
pH: 1.0
Temperature: 25 ° C
Current density Dk: 40 A / dm ²
Plating time: 7 seconds Plating frequency: 1 time (3rd Cu plating condition)
Plating bath composition: Cu 150 g / L to 250 g / L, sulfuric acid 100 g / L
pH: 1.0
Temperature: 40 ° C
Current density Dk: 5 A / dm ²
Plating time: 7 seconds Plating frequency: 1 time (10-point average roughness Rz measurement)
About the copper foil after the surface treatment of each experimental example, the surface roughness Rz was measured with an Olympus laser microscope OLS4000. Rz conforms to JIS B0601 1994. Using an objective lens 50 times, in the observation of the copper foil surface, the evaluation length is 258 μm, the cut-off value is zero, and the rolled copper foil is measured in the direction (TD) perpendicular to the rolling direction or electrolytic copper The foil was measured 10 times in the direction (TD) perpendicular to the traveling direction of the electrolytic copper foil in the electrolytic copper foil manufacturing apparatus, and each measurement position was changed 10 times, and the average value of 10 measurements was obtained. In addition, the measurement environmental temperature of surface roughness Rz by a laser microscope was 23-25 degreeC. About the copper foil which provided the surface treatment layer on both surfaces, the 10-point average roughness Rz became the same value on both surfaces.
(Measurement of arithmetic average roughness Ra)
About the copper foil after the surface treatment of each experimental example, the surface roughness Ra was measured with an Olympus laser microscope OLS4000. Ra conforms to JIS B0601 1994. Using an objective lens 50 times, in the observation of the copper foil surface, the evaluation length is 258 μm, the cut-off value is zero, and the rolled copper foil is measured in the direction (TD) perpendicular to the rolling direction or electrolytic copper The foil was measured 10 times in the direction (TD) perpendicular to the traveling direction of the electrolytic copper foil in the electrolytic copper foil manufacturing apparatus, and each measurement position was changed 10 times, and the average value of 10 measurements was obtained. In addition, the measurement environmental temperature of surface roughness Ra by a laser microscope was 23-25 degreeC. About the copper foil which provided the surface treatment layer on both surfaces, arithmetic mean roughness Ra became the same value on both surfaces.
(Measurement of adhesion amount of Co, Ni and other elements)
The adhesion amount of Co, Ni and other elements was measured by ICP emission analysis after dissolving a copper foil sample in a nitric acid solution having a concentration of 20% by mass. In Examples and Comparative Examples in which surface treatment layers were provided on both sides of copper foil, masking such as acid-resistant tape was performed on one side, and the surface treatment layer on one side was dissolved to measure the adhesion amount of Co, Ni and other elements. did. Then, measure the amount of adhesion of Co, Ni and other elements on the other side even if the above masking is taken, or use another sample to adhere Co, Ni and other elements on the other side. The amount was measured. The values listed in Table 1 were values on one side. About the copper foil which provided the surface treatment layer on both surfaces, the adhesion amount of Co, Ni, and another element became the same value on both surfaces. If Co, Ni and other elements are not dissolved in a 20% by mass nitric acid aqueous solution, the above ICP issuance analysis is performed after dissolving using a solution capable of dissolving Co, Ni and other elements. You may measure by. In addition, you may use a well-known liquid, a well-known acidic liquid, and a well-known alkaline liquid for the liquid which can dissolve Co, Ni, and another element.
(Evaluation of particle dropout)
(1) Tape test A transparent mending tape is affixed on the surface-treated surface of the surface-treated copper foil, and when the tape is peeled off in the direction of 180 °, the falling particles adhering to the tape adhesive surface cause the tape. The powder fall was evaluated from the appearance of the discoloration. When there was no discoloration of the tape, “◎”, when it became gray, “◯”, and when the tape discolored black, “×”.
(2) Conveyance roll confirmation In the manufacturing process of a secondary battery, when coating an electrode active material on the copper foil for collectors, the conveyance line of a roll to roll is used. Therefore, dropping off of the roughened particles on the copper foil surface treatment for the current collector becomes a problem on the roll of the transport line. Using a slit line device, which is used to adjust the product width of the current collector copper foil, the transport roll is often cleaned once every several thousand meters of copper foil transport. Evaluated. The state in which the roll was hardly soiled was “◎”, the state in which the roll was slightly fixed was “◯”, and the state in which the roll was significantly soiled was “x”.
(Evaluation of adhesion with active material)
The adhesion with the active material was evaluated by the following procedure.
(1) Artificial graphite having an average diameter of 9 μm and polyvinylidene fluoride are mixed at a weight ratio of 1: 9 and dispersed in a solvent N-methyl-2-pyrrolidone.
(2) The above active material is applied to the surface of the copper foil.
(3) The copper foil coated with the active material is heated at 90 ° C. for 30 minutes with a dryer. In this case, since the silane coupling agent has no OH group bonded to the copper surface, it hardly reacts with the copper surface due to a dehydration reaction with the unreacted silane coupling agent.
(4) After drying, cut into 20 mm squares and apply a load of 1.5 ton / mm ² × 20 seconds.
(5) The sample is cut into a grid pattern with a cutter, a commercially available adhesive tape (Cellotape (registered trademark)) is attached, a roller with a weight of 2 kg is placed, and the adhesive tape is crimped by reciprocating once.
(6) The active material remaining on the copper foil after peeling off the adhesive tape is obtained by capturing the surface image into a PC and binarizing to distinguish between the metallic luster portion of the copper surface and the black portion where the active material remains, The residual ratio of was calculated. The residual rate was an average value of three samples. For the determination of the active material adhesion, the residual ratio is less than 50% “x”, 50% to less than 70% “△”, 70% to less than 80% “◯”, 80% to less than 90% “◎”. 90% or more was designated as “「 ”.
(Heat resistance evaluation)
After cutting the surface-treated copper foil into a size of 20 cm × 20 cm, the copper foil cut sample is put into an oven heated to 300 ° C., and after 15 seconds, the copper foil sample is taken out of the oven and oxidized in the surface treatment. The degree of discoloration was evaluated. “O” indicates that no oxidative discoloration occurred, “△” indicates that less than 30% of a 20 cm × 20 cm size has undergone oxidative discoloration, and “×” indicates that oxidative discoloration occurs in 30% or more. It was.

(Evaluation results)
Examples 1-14 all had good particle dropout evaluation, good adhesion to the active material, and good heat resistance.
In Comparative Example 1, since the secondary particle layer was not provided, the ten-point average roughness Rz and the arithmetic average roughness Ra were out of the predetermined ranges, so that both the particle dropout evaluation and the adhesion were poor. Moreover, since the secondary particle layer was not formed and the covering plating was not provided, the heat resistance was also poor.
In Comparative Example 2, since the primary particle layer was not provided, the ten-point average roughness Rz deviated from the predetermined range, and therefore both the particle dropout evaluation and the adhesion were poor.
In Comparative Example 3, the primary particle layer and the secondary particle layer were provided. However, the ten-point average roughness Rz and the arithmetic average roughness Ra were out of the predetermined ranges, so that the evaluation of adhesion was only “Δ”.
In Comparative Example 4, the ten-point average roughness Rz was within a predetermined range, but the primary particle layer and the secondary particle layer could not be formed sequentially only by the rolling treatment, and thus the adhesion was insufficient. Moreover, since the covering plating layer was not provided, the heat resistance performance was poor.
In Comparative Example 5, the ten-point average roughness Rz is within a predetermined range. However, since the primary particle layer and the secondary particle layer cannot be sequentially formed under such plating conditions, the result of the particle drop test is not preferable, and the adhesion is not good. It was insufficient.

・ Treatment with cover plating solution (1) Zn-Cr
Liquid composition: potassium dichromate 1 to 10 g / L, Zn 0.1 to 5 g / L
Liquid temperature: 40-60 degreeC
pH: 0.5-10
Current density: 0.01 to 2.6 A / dm ²
Energizing time: 0.05-30 seconds

・ Treatment with cover plating solution (5) Co-Ni
Liquid compositions: Co1~20g / L, N i 1~20g / L
Liquid temperature: 30-80 degreeC
pH: 1.5-3.5
Current density: 1 to 20 A / dm ²
Energizing time: 0.1 to 4 seconds

・ Treatment with cover plating solution (6) Zn-Ni
Liquid compositions: Zn1~30g / L, N i 1~30g / L
Liquid temperature: 40-50 degreeC
pH: 2-5
Current density: 0.5 to 5 A / dm ²
Energizing time: 0.01 to 0.3 seconds

In Comparative Example 4, as shown in Table 1, instead of forming the primary particle layer and the secondary particle layer under the predetermined conditions, the surface temper-rolled with a rolling roll having a roughened surface was used in an atmospheric atmosphere. Thermal oxidation treatment was performed, and then heat reduction treatment was performed in a nitrogen atmosphere containing 1% CO.
In Comparative Example 5, as shown in Table 1, instead of forming the primary particle layer and the secondary particle layer under the predetermined conditions, the first Cu plating, the second Cu plating, and the third Cu plating were sequentially performed under the following conditions. gave.
(First Cu plating conditions)
Plating bath composition: Cu 150 g / L to 250 g / L, sulfuric acid 100 g / L
pH: 1.0
Temperature: 40 ° C
Current density Dk: 5 A / dm ²
Plating time: 7 seconds Plating frequency: 1 time (2nd Cu plating condition)
Plating bath composition: Cu 50 g / L to 150 g / L, sulfuric acid 130 g / L
pH: 1.0
Temperature: 25 ° C
Current density Dk: 40 A / dm ²
Plating time: 7 seconds Plating frequency: 1 time (3rd Cu plating condition)
Plating bath composition: Cu 150 g / L to 250 g / L, sulfuric acid 100 g / L
pH: 1.0
Temperature: 40 ° C
Current density Dk: 5 A / dm ²
Plating time: 7 seconds Plating frequency: 1 time (10-point average roughness Rz measurement)
About the copper foil after the surface treatment of each experimental example, the surface roughness Rz was measured with an Olympus laser microscope OLS4000. Rz conforms to JIS B0601 1994. Using an objective lens 50 times, in the observation of the copper foil surface, the evaluation length is 258 μm, the cut-off value is zero, and the rolled copper foil is measured in the direction (TD) perpendicular to the rolling direction or electrolytic copper The foil was measured 10 times in the direction (TD) perpendicular to the traveling direction of the electrolytic copper foil in the electrolytic copper foil manufacturing apparatus, and each measurement position was changed 10 times, and the average value of 10 measurements was obtained. In addition, the measurement environmental temperature of surface roughness Rz by a laser microscope was 23-25 degreeC. About the copper foil which provided the surface treatment layer on both surfaces, the 10-point average roughness Rz became the same value on both surfaces.
(Measurement of arithmetic average roughness Ra)
About the copper foil after the surface treatment of each experimental example, the surface roughness Ra was measured with an Olympus laser microscope OLS4000. Ra conforms to JIS B0601 1994. Using an objective lens 50 times, in the observation of the copper foil surface, the evaluation length is 258 μm, the cut-off value is zero, and the rolled copper foil is measured in the direction (TD) perpendicular to the rolling direction or electrolytic copper The foil was measured 10 times in the direction (TD) perpendicular to the traveling direction of the electrolytic copper foil in the electrolytic copper foil manufacturing apparatus, and each measurement position was changed 10 times, and the average value of 10 measurements was obtained. In addition, the measurement environmental temperature of surface roughness Ra by a laser microscope was 23-25 degreeC. About the copper foil which provided the surface treatment layer on both surfaces, arithmetic mean roughness Ra became the same value on both surfaces.
(Measurement of adhesion amount of Co, Ni and other elements)
The adhesion amount of Co, Ni and other elements was measured by ICP emission analysis after the surface treatment layer of the copper foil sample was dissolved in an aqueous nitric acid solution having a concentration of 20% by mass. In Examples and Comparative Examples in which surface treatment layers were provided on both sides of copper foil, masking such as acid-resistant tape was performed on one side, and the surface treatment layer on one side was dissolved to measure the adhesion amount of Co, Ni and other elements. did. Then, measure the amount of adhesion of Co, Ni and other elements on the other side even if the above masking is taken, or use another sample to adhere Co, Ni and other elements on the other side. The amount was measured. The values listed in Table 1 were values on one side. About the copper foil which provided the surface treatment layer on both surfaces, the adhesion amount of Co, Ni, and another element became the same value on both surfaces. If Co, Ni and other elements are not dissolved in a 20% by mass nitric acid aqueous solution, the above ICP issuance analysis is performed after dissolving using a solution capable of dissolving Co, Ni and other elements. You may measure by. In addition, you may use a well-known liquid, a well-known acidic liquid, and a well-known alkaline liquid for the liquid which can dissolve Co, Ni, and another element.
(Evaluation of particle dropout)
(1) Tape test A transparent mending tape is affixed on the surface-treated surface of the surface-treated copper foil, and when the tape is peeled off in the direction of 180 °, the falling particles adhering to the tape adhesive surface cause the tape. The powder fall was evaluated from the appearance of the discoloration. When there was no discoloration of the tape, “◎”, when it became gray, “◯”, and when the tape discolored black, “×”.
(2) Conveyance roll confirmation In the manufacturing process of a secondary battery, when coating an electrode active material on the copper foil for collectors, the conveyance line of a roll to roll is used. Therefore, dropping off of the roughened particles on the copper foil surface treatment for the current collector becomes a problem on the roll of the transport line. Using a slit line device, which is used to adjust the product width of the current collector copper foil, the transport roll is often cleaned once every several thousand meters of copper foil transport. Evaluated. The state in which the roll was hardly soiled was “◎”, the state in which the roll was slightly fixed was “◯”, and the state in which the roll was significantly soiled was “x”.
(Evaluation of adhesion with active material)
The adhesion with the active material was evaluated by the following procedure.
(1) Artificial graphite having an average diameter of 9 μm and polyvinylidene fluoride are mixed at a weight ratio of 1: 9 and dispersed in a solvent N-methyl-2-pyrrolidone.
(2) The above active material is applied to the surface of the copper foil.
(3) The copper foil coated with the active material is heated at 90 ° C. for 30 minutes with a dryer. In this case, since the silane coupling agent has no OH group bonded to the copper surface, it hardly reacts with the copper surface due to a dehydration reaction with the unreacted silane coupling agent.
(4) After drying, cut into 20 mm squares and apply a load of 1.5 ton / mm ² × 20 seconds.
(5) The sample is cut into a grid pattern with a cutter, a commercially available adhesive tape (Cellotape (registered trademark)) is attached, a roller with a weight of 2 kg is placed, and the adhesive tape is crimped by reciprocating once.
(6) The active material remaining on the copper foil after peeling off the adhesive tape is obtained by capturing the surface image into a PC and binarizing to distinguish between the metallic luster portion of the copper surface and the black portion where the active material remains, The residual ratio of was calculated. The residual rate was an average value of three samples. For the determination of the active material adhesion, the residual ratio is less than 50% “x”, 50% to less than 70% “△”, 70% to less than 80% “◯”, 80% to less than 90% “◎”. 90% or more was designated as “「 ”.
(Heat resistance evaluation)
After cutting the surface-treated copper foil into a size of 20 cm × 20 cm, the copper foil cut sample is put into an oven heated to 300 ° C., and after 15 seconds, the copper foil sample is taken out of the oven and oxidized in the surface treatment. The degree of discoloration was evaluated. “O” indicates that no oxidative discoloration occurred, “△” indicates that less than 30% of a 20 cm × 20 cm size has undergone oxidative discoloration, and “×” indicates that oxidative discoloration occurs in 30% or more. It was.

Claims (21)

Copper foil, and
It has a surface treatment layer on at least one surface side of the copper foil,
The surface treatment layer has a primary particle layer and a secondary particle layer,
The 10-point average roughness Rz when the surface treatment layer surface is measured using a laser microscope with a wavelength of 405 nm in accordance with JIS B0601 1994 is 1.8 μm or more.
Surface-treated copper foil for batteries.   2. The surface-treated copper foil for a battery according to claim 1, wherein the surface-treated layer surface has an arithmetic average roughness Ra of 0.26 μm or more when measured using a laser microscope having a wavelength of 405 nm in accordance with JIS B0601 1994. .   The battery surface according to claim 1 or 2, wherein the primary particle layer includes one or more selected from the group consisting of Cu, W, Ti, As, V, Mo, Ni, Co, Cr, Zn, P, and Sn. Treated copper foil.   The secondary particle layer includes at least one selected from the group consisting of Cu, W, Ti, As, V, Mo, Ni, Co, Cr, Zn, P, and Sn. The surface-treated copper foil for batteries described in 1. 5. The surface treatment layer contains a total of 100 μg / dm ² or more of at least one selected from the group consisting of Cu, W, Ti, As, V, Mo, Ni, Co, Cr, Zn, P, and Sn. The surface-treated copper foil for batteries as described in any one of these. The said surface treatment layer contains 10000 microgram / dm < ² > or less in total of 1 or more types selected from the group which consists of Cu, W, Ti, As, V, Mo, Ni, Co, Cr, Zn, P, and Sn. The surface-treated copper foil for batteries as described in any one of these. The surface-treated copper foil for a battery according to any one of claims 1 to 6, wherein the surface-treated layer contains Ni, and an adhesion amount of Ni is 100 µg / dm ² or more. The surface-treated copper foil for a battery according to any one of claims 1 to 7, wherein the surface-treated layer contains Ni, and an adhesion amount of Ni is 4500 µg / dm ² or less. The surface-treated copper foil for a battery according to any one of claims 1 to 8, wherein the surface treatment layer contains Co, and the adhesion amount of Co is 100 µg / dm ² or more. The surface-treated copper foil for a battery according to any one of claims 1 to 9, wherein the surface treatment layer contains Co, and the adhesion amount of Co is 6000 µg / dm ² or less.   The surface-treated copper foil for a battery according to any one of claims 1 to 10, wherein the primary particle layer is made of Cu.   The surface-treated copper foil for a battery according to any one of claims 1 to 11, wherein the secondary particle layer is made of Cu, Co, or Ni.   The copper foil is a total of at least one selected from the group consisting of In, Au, Pd, Ag, Cr, Fe, P, Ti, Sn, Zn, Mn, Mo, Co, Ni, Si, Zr, B, and Mg. The surface-treated copper foil for a battery according to any one of claims 1 to 12, comprising 5 mass ppm or more and 0.3 mass% or less.   The copper foil is a total of at least one selected from the group consisting of In, Au, Pd, Ag, Cr, Fe, P, Ti, Sn, Zn, Mn, Mo, Co, Ni, Si, Zr, B, and Mg. The surface-treated copper foil for a battery according to any one of claims 1 to 12, comprising 5 mass ppm or more and 300 mass ppm or less.   The copper foil is a total of at least one selected from the group consisting of In, Au, Pd, Ag, Cr, Fe, P, Ti, Sn, Zn, Mn, Mo, Co, Ni, Si, Zr, B, and Mg. The surface-treated copper foil for a battery according to any one of claims 1 to 12, comprising 301 mass ppm or more and 0.3 mass% or less.   The surface treatment layer further includes at least one layer selected from the group consisting of a heat-resistant layer, a rust prevention layer, a chromate treatment layer, a silane coupling treatment layer, a plating layer, and a resin layer on the secondary particle layer. The surface-treated copper foil for a battery according to any one of claims 1 to 15.   It is an object for secondary batteries, The surface-treated copper foil for batteries as described in any one of Claims 1-16.   The surface-treated copper foil for a battery according to any one of claims 1 to 17, which is for a secondary battery current collector.   The electrical power collector which has the surface-treated copper foil for batteries as described in any one of Claims 1-18.   The electrode which has the surface-treated copper foil for batteries as described in any one of Claims 1-18.   A battery comprising the surface-treated copper foil for a battery according to any one of claims 1 to 18, the current collector according to claim 19, or the electrode according to claim 20.