CN115070344A

CN115070344A - Electrode current collector and preparation method thereof

Info

Publication number: CN115070344A
Application number: CN202210285272.5A
Authority: CN
Inventors: 不公告发明人
Original assignee: Individual
Current assignee: Individual
Priority date: 2022-03-23
Filing date: 2022-03-23
Publication date: 2022-09-20
Anticipated expiration: 2042-03-23
Also published as: CN115070344B

Abstract

The invention provides an electrode current collector and a preparation method thereof, wherein when the texturing operation of a metal roller is carried out, the metal roller is controlled to sequentially form an axial anchor point group and a circumferential anchor point group, and the preparation processes of the axial anchor point group and the circumferential anchor point group are independent. In the rolling process of foil, arranging of texturing point self is the level form setting, at rolling in-process, carries out tension control to the foil through unwinding equipment and rolling equipment, consequently can avoid the circumstances such as the vertical line texture that appears among the prior art even fold to take place effectively, ensures that the mass flow body foil face type is good, avoids the foil to take place the shrink on the width direction simultaneously, and then avoids the mass flow body because of a series of service problems that the face type is bad and the width shrink brings.

Description

Electrode current collector and preparation method thereof

Technical Field

The invention relates to the technical field of preparation of electrode current collectors, in particular to a preparation method of an electrode current collector and the prepared electrode current collector.

Background

In the prior art, the electrode current collector is applied to energy storage devices such as electrolytic capacitors, super capacitors, lithium ion super capacitors, primary lithium batteries, lithium ion batteries, sodium ion batteries and the like, and mainly comprises aluminum foils, copper foils and lithium tapes with the thickness of 2-20 microns. In order to increase the contact area and the bonding force between the current collector of the device and the electrode coating material and reduce the contact impedance, the conventional method adopts aluminum foils and copper foils which are chemically etched or punched, and carbon-coated aluminum foils and copper foils which are coated with conductive coatings on the basis of optical foils.

For the etched foil, because chemical agents are needed for etching, the manufacturing cost of the foil is increased, extra chemical pollution is caused, the base foil subjected to chemical etching is influenced by etching, and the mechanical property of the foil is greatly reduced; meanwhile, because the etched small holes are often small, the electrode material is overhead on the small holes during coating, so that the larger contact surface area and the higher energy density of the surface of the etched foil are limited; furthermore, the etched foil does not contribute much to the roughness increase and therefore the surface area increase. These factors limit the widespread use of etched foils, and currently only electrolytic capacitors, supercapacitors, etc. are still using etched foils, and these devices are also looking for a more cost-effective alternative.

For the punching foil, because the foil needs to be punched continuously in a large area by adopting precise equipment means such as laser and the like, the production efficiency is low, the manufacturing cost is high, the mechanical performance of the foil after excessive punching is greatly reduced, but a small amount of punching has little effect on improving various application performances of the foil, and therefore, the punching foil is difficult to be widely applied.

In order to solve the above problems, the prior art provides a method for rolling a roughened surface current collector foil in a staggered manner, as shown in fig. 1, which includes the following steps: step 100, respectively erecting a first roller 1 and a second roller 2 with smooth surfaces on a numerical control lathe, and processing annular bulges with preset sizes and distribution positions on the surfaces of the rollers by using a laser texturing system 3, wherein a first annular bulge 1a is formed on the first roller 1, and a second annular bulge 2a is formed on the second roller 2, wherein the first annular bulge and the second annular bulge are arranged in a spiral shape; and 200, loading the manufactured double rollers in a concave-convex shape spiral curve symmetrical mode, adjusting the relative positions of the two rollers to enable the annular bulges on the surfaces of the two rollers to be staggered, penetrating the foil 3 through a gap between the two rollers, and applying rolling force to form a surface texturing structure formed by non-penetrating pits on the upper surface and the lower surface of the foil.

However, in the above scheme, as shown in fig. 1 and 3, the force applied to the foil 3 during the rolling process is analyzed, the angle of the spiral line on the roller is very small, a plurality of roughened points extending along the vertical straight line direction in fig. 3 are formed on the foil 3, and because the distances between the roughened points cannot be uniform, the plurality of concave and convex roughened points form inward local concentrated stresses Fa and Fb on two sides of the edge after being arranged in the same straight line, and in addition, unwinding and winding operations need to be performed on two sides of the foil 3, and the generated tension aggravates the local concentration of the linear stress, so that macroscopically, two inward pulling forces, that is, F, are applied to two sides of the foil 3 at the same time _{Drawing 1} And F _{Drawing 2} . The concentrated stress and the pulling force on both sides acting on the foil can result in the formation of vertical lines 3b on the foil 3, and even in the formation of a plurality of strip-like folds adjacent to each other on the foil 3 when the force of the vertical lines 3b is too great. Further, the multiple sets of linear depressions at the positions of the vertical stripes 3b will cause the foil to contract inwardly along the x-axis direction in fig. 3, resulting in the movement of the two sides of the foil 3 to the positions of the contraction lines 3a in the figure.

The shrinking foil 3 will present the following problems: because the foil material has produced vertical lines or fold, produce easily when coating electrode material and pile up, thereby it is inhomogeneous to cause the electrode material of device electrode surface distribution, both coat the surface density inequality, in lithium ion battery, such condition can and then lead to the local excessive lithium deposition of pole piece, when having lost lithium ion and lead to lithium ion battery capacity loss, accumulational lithium can produce lithium dendrite, lithium dendrite accumulates after certain height, can pierce lithium ion battery diaphragm etc. and take place interior short-circuit phenomenon with another electrode contact, thereby cause the device to overheat, safety problems such as burning.

Disclosure of Invention

Therefore, the technical problem to be solved by the invention is to overcome the defects that in the prior art, the bimetallic rollers are distributed and rolled in a staggered manner in a spiral longitudinal line form lattice manner, and the obtained current collector foil has a poor surface shape, so that the density distribution of the coating surface of the pole piece of the manufactured energy storage device is uneven, and further the device is easy to have capacity reduction, internal short circuit and the like.

To this end, a method for preparing an electrode current collector includes the steps of:

placing a first roller to be roughened at a set position;

the laser texturing system is corresponding to a first starting texturing point position of a first roller to be textured, the laser texturing system is controlled to be started, and texturing operation is carried out on the first starting texturing point position;

controlling the laser texturing system to horizontally move relative to a first roller to be textured, wherein the horizontal distance between the first initial texturing point and the first axial texturing point is x 1;

repeatedly controlling the laser texturing system to horizontally move relative to the first roller to be textured, so that the distance between two adjacent axial texturing points is x1, and forming a first row of axial anchor point groups parallel to the axis of the first roller to be textured on a circumferential generatrix of the first roller to be textured;

controlling the first roller to be roughened to rotate to a second row of first circumferential texturing points, wherein the circumferential distance between the second row of first circumferential texturing points and the corresponding first row of first axial texturing points is y1, controlling the first roller to be roughened to horizontally move by taking the second row of first circumferential texturing points as a starting point, and forming a second row of axial anchor points in the direction of a second generatrix of the roller cylinder;

repeatedly controlling the first roller to be roughened to rotate, wherein the distance between two adjacent circumferential texturing points is y1, and forming the N-row axial anchor point group by taking the first circumferential texturing point corresponding to the N-row as a starting point;

selecting a second metal roller to be roughened, wherein the size of the second metal roller to be roughened is consistent with that of the first roller to be roughened, and repeating the step of preparing the first roller to be roughened to obtain a second roller to be roughened;

the first texturing roller and the second texturing roller which are obtained through preparation are oppositely arranged according to a preset mode, and a rolling gap is formed between the first texturing roller and the second texturing roller;

firstly, controlling a first starting texturing point of the first texturing roller and a second starting texturing point of the second roller to be textured to be oppositely arranged;

controlling the first texturing roller to rotate relative to the second texturing roller, wherein the circumferential relative rotation distance is (y1-a)/2, and a is the diameter of the first texturing point;

controlling the first texturing roller and the second texturing roller to offset along the axial direction, wherein the offset distance is (x 1-a)/2;

and drawing the foil from the unwinding end, rolling the foil through a rolling gap between the two rollers, controlling the rolling mill to press down, simultaneously starting the rolling mill, the unwinding equipment and the winding equipment, adjusting the tension control device, and gradually adjusting the rolling speed and the unwinding and winding speed.

The preparation method of the electrode current collector further comprises the following steps:

the method comprises the steps of oppositely grinding, namely measuring the surface roughness Ra, Rz and Rt of the bimetal roller, controlling the first texturing roller and the second texturing roller to be arranged side by side, enabling transverse anchor point groups to be staggered, controlling the outer surfaces of the first texturing roller and the second texturing roller to be in mutual contact and pressed down, controlling the pressing-down gap to be 1-5 times of Ra, and starting a rolling mill to oppositely grind the textured bimetal roller;

and carrying out dust removal operation on the first texturing roller and the second texturing roller after the opposite grinding operation is finished.

According to the preparation method of the electrode current collector, provided by the invention, (y1+ a) can be divided by the circumference (pi x d) of the roller, wherein d is the diameter of the first roller to be roughened.

According to the preparation method of the electrode current collector, the thickness of the foil to be rolled is 2-20 micrometers.

According to the preparation method of the electrode current collector, the pressure applied to the foil to be rolled is 5-100 Mpa.

The invention provides an electrode current collector which is obtained by adopting the preparation method provided by the invention.

The technical scheme of the invention has the following advantages:

1. according to the preparation method of the electrode current collector, when the texturing operation of the metal roller is carried out, the metal roller is controlled to sequentially form the axial anchor point group and the circumferential anchor point group, and the preparation processes of the axial anchor point group and the circumferential anchor point group are independent.

In the prior art, when the surface roughening operation is performed on the metal roller, a spiral line formed by circumferentially compact protruding points formed by the two rollers can form vertical stress concentration on the surface of a foil when the foil is pressed in a staggered mode, so that the surface of the foil presents obvious vertical lines and even vertical wrinkles.

And in this application, at the rolling in-process of foil, the arrangement of texturing point self is horizontal transverse arrangement, at rolling in-process, even form horizontal local stress concentration by rolled foil texturing point group, nevertheless exert certain tension to the foil through unwinding equipment and rolling equipment, can effectively offset the stress of local concentration, consequently can avoid the circumstances such as the vertical line texture that appears among the prior art or local fold to take place effectively, and then can avoid the foil to take place the shrink on the width direction, thereby ensure that the face type is good.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and other drawings can be obtained by those skilled in the art without creative efforts.

FIG. 1 is a schematic view of a rolling method according to the background of the invention;

FIG. 2 is a schematic structural view of a rolling method according to the background art of the present invention;

FIG. 3 is a graph of the analysis of the stress of a foil during rolling in the prior art;

FIG. 4 is a stress analysis diagram of the foil in the rolling process according to the technical scheme of the invention;

FIG. 5 is a schematic view of the arrangement of rollers and the structure of the roughened metal foil according to the present invention;

FIG. 6 is a schematic view of an apparatus for texturing a foil according to the present invention;

FIG. 7 is a schematic structural view of a first texturing roller and a second texturing roller provided by the present invention;

FIG. 8 is a schematic diagram of the arrangement of the second texturing roller in the rolling process according to the technical scheme of the invention;

FIG. 9 is a schematic view of a rolling process;

FIG. 10 is a schematic structural view of a roughened metal foil obtained by rolling;

the reference signs in the background of the application indicate:

1. a first roll; 2. a second roll; 1a, a first annular bulge; 2a, a second roller; 3. a laser texturing system; 3a, a contraction wire; 3b, vertical stripes;

description of reference numerals in the examples:

1. a laser texturing system; 2. a first roller to be roughened; 21. a first point of incipient hair formation; 22. a first axial frosted point location; 23. a first group of axial anchor points; 24. a first circumferential frosted spot; 25. a first group of circumferential anchor points; 3. a second roller to be roughened; 32. a second axial frosted spot; 33. a second set of axial anchor points; 35. a second set of circumferential anchor points; 4. a machine tool; 5. a horizontal rail; 7. a smooth metal foil; 8. roughening the metal foil; 9. a first texturing roller; 10. a second texturing roller; 11. unwinding equipment; 12. and (7) winding equipment.

Detailed Description

The technical solutions of the present invention will be described clearly and completely with reference to the accompanying drawings, and it should be understood that the described embodiments are some, but not all embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of description and simplicity of description, but do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

In the description of the present invention, it should be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.

In addition, the technical features involved in the different embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.

Example 1

The embodiment provides a preparation method of an electrode current collector, and the electrode current collector is mainly applied to a battery. The method comprises the following steps:

placing a first roller to be roughened at a set position;

specifically, the first roller to be roughened can be made of a special alloy material for the roller. Meanwhile, the set position can be arranged on a lathe, and belongs to the initial processing position of the first roller to be roughened;

the laser texturing system 1 is corresponding to a first texturing point 21 of a first roller to be textured, the laser texturing system 1 is controlled to be started, and texturing operation is carried out on the first texturing point 21;

the laser texturing technique is characterized in that a pulse laser beam with high energy and high repetition frequency is irradiated on the surface of a roller through negative defocusing after being focused to implement preheating and strengthening, a focused point is incident on the surface of the roller to form a tiny molten pool, and meanwhile, an auxiliary gas with set pressure and flow is applied to the tiny molten pool by a side blowing device, so that the fusant in the molten pool is accumulated to the edge of the molten pool as much as possible to form an arc-shaped boss according to the specified requirement.

Specifically, the structure of the laser texturing system 1 itself is not limited as long as a specific texturing spot can be formed on the roll, and the formed texturing spot includes a convex portion and a concave portion;

controlling the laser texturing system 1 to horizontally move relative to the first roller to be textured, wherein the horizontal distance between the first initial texturing point 21 and the first axial texturing point 22 is x 1;

in particular, the movement of the laser texturing system 1 relative to the first roll to be textured is not limited. The first roller to be roughened can be controlled to be static, and the laser texturing system 1 is controlled to move; the laser texturing system 1 can also be controlled to stand, and the first roller to be textured is controlled to move.

In this embodiment, as shown in fig. 6, a texturing operation is implemented on the machine tool 4, the laser texturing system 1 is arranged on the horizontal rail 5, the power device is connected to the laser texturing system 1, the power device may be a motor, and after the motor is started, the laser texturing system 1 moves on the horizontal rail 5, so as to implement a movement relative to the first roll to be textured.

Repeatedly controlling the laser texturing system 1 to horizontally move relative to the first roller to be textured, so that the distance between two adjacent first axial texturing points 22 is x1, until a first row of axial anchor point groups parallel to the axis of the first roller to be textured is formed on a circumferential generatrix of the first roller to be textured;

in this embodiment, as shown in fig. 7, a plurality of first axial textured points 22 are formed, and a connection line between the plurality of first axial textured points 22 is arranged along a horizontal shape, so as to form a first axial anchor group 23, specifically, the first axial anchor group 23 has a structure as shown in fig. 3, and the first axial anchor group 23 extends along a horizontal direction, that is, an x-axis direction in fig. 3.

As shown in fig. 7, the first axial anchor group 23 includes a plurality of first axial texturing points 22 arranged side by side, and the length of the first roll to be textured 2 is an integral multiple of the distance between two adjacent first axial texturing points 22.

Controlling the first roller to be roughened 2 to rotate to a second row of first circumferential texturing positions 24, wherein the circumferential distance between the second row of first circumferential texturing positions 24 and the corresponding first row of first axial texturing positions 22 is y1, controlling the first roller to be roughened 2 to horizontally move with the second row of first circumferential texturing positions 24 as a starting point, and forming a second row of first axial anchor points 23 in the second generatrix direction of the roller cylinder; the plurality of first circumferential frosted points 24 form a first circumferential group of anchor points 25.

That is, as shown in fig. 3, after the arrangement of one first axial anchor point group 23 is completed, the first roll to be roughened 2 is controlled to rotate to the first circumferential texturing point 24 along the y-axis direction, and at this time, a plurality of first axial texturing points 22 are sequentially formed along the x-axis direction with the first circumferential texturing point 24 as a starting point.

In this step, the position of the first circumferential texturing point 24 is not limited, and it may correspond to the tail of the previous first axial anchor point group 23, and at this time, only the first roller to be textured 2 needs to be controlled to rotate; as a variant, it is also possible to associate the first circumferential texturing station 24 with the start of the last first axial anchor group 23, in which case it is necessary to first control the laser texturing system 1 to reset and then control the first roll to be textured to rotate.

Specifically, the rotation direction of the first roller to be roughened 2 is not limited, and it may rotate clockwise or counterclockwise as long as the rotation operation can be completed.

Repeatedly controlling the first roll to be roughened 2 to rotate, as shown in fig. 7, the distance between two adjacent first circumferential texturing points 24 is y1, and the first axial anchor point group 23 in the nth row is formed by using the first circumferential texturing point 24 in the nth row as a starting point;

after the step is completed, a plurality of first axial anchor point groups 23 parallel to the axis of the first roller to be roughened can be formed, and at this time, the roughening point positions are uniformly arranged in the x-axis direction and the y-axis direction of the first roller to be roughened at the same time.

Selecting a second metal roller to be roughened, wherein the size of the second metal roller to be roughened is consistent with that of the first roller to be roughened, and repeating the step of preparing the first roller to be roughened to obtain a second metal roller to be roughened;

specifically, the second to-be-roughened metal roller and the first to-be-roughened roller may be made of the same material or different materials, as long as parameters such as the diameter and the length between the first to-be-roughened roller 2 and the second to-be-roughened roller 3 are ensured to be consistent. And meanwhile, controlling the second metal roller to be roughened to adopt the same processing steps as the first roller to be roughened, so as to obtain two rollers with consistent layout of the roughening points.

In this embodiment, a second axial anchor point group 33 and a second circumferential anchor point group 35 are sequentially formed on the second metal roll to be roughened, the second axial anchor point group 33 includes a plurality of second axial roughened points 32, and the second circumferential anchor point group 35 includes a plurality of second circumferential roughened points.

Through the texturing action, the first roller to be textured 2 becomes a first texturing roller 9, and the second roller to be textured 3 becomes a second texturing roller 10.

The first texturing roller 9 and the second texturing roller 10 which are obtained through preparation are oppositely arranged, a rolling gap is formed between the first texturing roller 9 and the second texturing roller 10, and the foil to be rolled is controlled to pass through the rolling gap.

Specifically, the smooth metal foil 7 is selected to enter a rolling gap, a roughened metal foil 8 is obtained after rolling, and the roughened metal foil 8 is used in subsequent tests and products.

The adjustment steps for the first texturing roller and the second texturing roller are as follows: firstly, controlling a first starting texturing point 21 of the first texturing roller 9 and a second starting texturing point of the second texturing roller 10 to be oppositely arranged;

the first starting texturing point 21 corresponds to the same position on the first roller to be textured 2 and the first texturing roller 9, and the second starting texturing point corresponds to the same position on the second roller to be textured 3 and the second texturing roller 10;

controlling the first texturing roller 9 to rotate relative to the second texturing roller 10, moving the rollers from m point to n point position in the figure as shown in fig. 8, wherein the circumferential relative rotation distance is (y1-a)/2, and a is the diameter of the first texturing starting point 21;

controlling the first texturing roller 9 and the second texturing roller 10 to offset along the axial direction, wherein the offset distance is (x 1-a)/2;

and controlling the unwinding device 11 and the winding device 12 to start, and enabling the foil to be rolled to pass through the rolling gap. And drawing the foil from the unwinding end, rolling the foil through a rolling gap between the two rollers, controlling the rolling mill to press down, simultaneously starting the rolling mill, the unwinding equipment and the winding equipment, adjusting the tension control device, and gradually adjusting the rolling speed and the unwinding and winding speed.

Specifically, as shown in fig. 9, in the rolling process of the smooth-faced metal foil 7, the unwinding device 11 and the winding device 12 respectively apply tension to the smooth-faced metal foil 7, so that the smooth-faced metal foil 7 is in a tensioned state in the whole rolling process.

The stress condition of the foil obtained by the present embodiment was analyzed:

as shown in fig. 4, in the foil obtained by the embodiment, in the rolling process of the foil, the textured points are linearly arranged in the X-axis direction and form a plurality of transverse textured point groups, at this time, the concave-convex textured point groups respectively generate inward concentrated stress of Fa and Fb in the y-axis direction in the figures at two sides of the foil, and the tension control for winding and unwinding in the rolling process generates two outward tensile forces, that is, F _{Drawing 1} And F _{Drawing 2} So that F can be adjusted by the tension _{Drawing 1} ＝Fa，F _{Drawing 2} The two outward pulling forces and the two inward concentrated stresses cancel each other out. Therefore, it is possible to effectively avoid the occurrence of abnormal conditions such as wrinkles or creases.

In particular, the rolling process is completed on a rolling mill. In this embodiment, after the first and second roughening rolls 9 and 10 are prepared, the rolls need to be cooled, and after cooling, the rolls are taken off and placed on a dry, clean, flexible support, and wait for installation on a rolling mill.

Specifically, with the arrangement described above, as shown in fig. 5, in the finally formed roughened metal foil 8, first axial anchor group 23 and second axial anchor group 33 are alternately arranged along the extending direction of the y-axis, but second axial anchor group 33 is offset from first axial anchor group 23 along the x-axis direction by (x 1-a)/2. At this time, as shown in the area C in fig. 5, the connecting line between the first axial textured point 22 and the second axial textured point 32 forms an oblique line, and in this embodiment, the oblique angle of the oblique line ranges from 10 ° to 80 °.

Specifically, as shown by an arrow c in fig. 5, the textured dots appear alternately in a direction inclined at a certain angle.

Further, after finishing the preparation actions of the first texturing roller and the second texturing roller, the method further comprises the following steps: the method comprises the steps of oppositely grinding, namely measuring the surface roughness Ra, Rz and Rt of the bimetal roller, controlling the first texturing roller and the second texturing roller to be arranged in parallel, enabling a transverse anchor point group to be staggered front and back, controlling the outer surfaces of the first texturing roller and the second texturing roller to be in contact with each other and to be pressed down, controlling the pressing-down gap to be 1-5 times of Ra, and starting a rolling mill to oppositely grind the textured bimetal roller;

Specifically, the dust removal step includes: installing dust removal roller brushes with suction force, which are consistent with the width of the rollers and connected with a dust cleaning device, on one side of the two rollers on the rolling machine, wherein the diameter of bristles is within 500 micrometers, opening the dust cleaning device to suck away the brushed particles and dust while the roller brushes, and rotating to brush and suck in the reciprocating manner until no obvious metal impurities are adsorbed on the magnetic bar;

the demagnetizing step comprises the following steps: on one side of two rollers on the rolling machine, the lower part of the roller brush is provided with magnetic bars with the same width as the rollers, the magnetic bars are not contacted with the rollers, the distance is between 1mm and 50mm, the magnetic force of the magnetic bars is used for absorbing away the fine metal magnetic particles which are not removed by the dust removal roller brush, meanwhile, the effect of the roller brush for removing the particles is tested, the magnetic bars exist all the time, and when obvious impurities are found to be attached to the magnetic bars, the magnetic bars need to be detached in time and the impurities need to be removed.

Through the operation, the flatness of the surface of the texturing roller can be effectively improved.

Further, the properties of the obtained foil are analyzed, and the preparation process and the analysis result are as follows:

the first roller to be roughened 2 and the second roller to be roughened 3, each having a diameter d of 150mm and an effective width L of 500mm, were roughened to obtain a roughened point having a diameter a of 90 μm, a bump height of 2.5 μm, L1 of 100mm, x1 of 150.4 μm, and y1 of 150.4 μm. The first texturing roller 9 and the second texturing roller 10 are arranged on a roller press, and the transverse spacing between the starting points of the two rollers is adjusted to be (x 1-a)/2-30.2 mu m, and the longitudinal spacing is adjusted to be (x 1-a)/2-30.2 mu m. The copper foil of 8 μm was placed between the two rolls, the roll press was started and the twin rolls were pre-ground with a pre-grinding gap of 10 μm. After the pre-grinding is finished, adjusting appropriate pressure to carry out double-roller imprinting, preparing a foil, preparing a cylindrical lithium iron phosphate anode pole piece and a multiplying power type lithium ion battery with the capacity of 1500mah, and respectively carrying out the following tests:

performance of

Further, in the present embodiment, in order to effectively ensure the uniform arrangement of the resulting textured dots, the dimensions involved are defined as follows;

the sizes of the first starting frosted point 21, the second starting frosted point, the first axial frosted point 22, the second axial frosted point 32, the first circumferential frosted point 24 and the second circumferential frosted point are kept consistent, and for convenience of description, the starting frosted points can be collectively called as frosted points;

(y1+ a) is divisible by the roll circumference (pi x d), d being the diameter of the first roller to be roughened 2 (first roller to be roughened 9), pi being the circumferential constant;

y1 is 1-5 times the diameter a of the textured spot;

the thickness of the foil to be rolled is 2-20 μm;

the pressure applied to the foil to be rolled is 5-100 Mpa.

The roughened metal foil 8 manufactured by the embodiment has the advantages that the roughness Rz and Rt values of the surface appearance are closer to Ra values than roughened foils manufactured by other methods, adverse effects brought to energy storage devices due to too many protruding peaks are avoided, the method is more suitable for thin foils, excessive stamping of the foils cannot be caused, and the phenomenon that the mechanical performance of the thin foils is greatly reduced or even the thin foils are broken is avoided.

Example 2

The embodiment provides an electrode current collector obtained by the preparation method provided in embodiment 1, and the morphology of the electrode current collector is shown in fig. 10.

The electrode current collector provided in this embodiment may be applied to a lithium ion battery, and for the lithium ion battery, a commonly used positive electrode current collector is an aluminum foil, and a negative electrode current collector is a copper foil.

It should be understood that the above examples are only for clarity of illustration and are not intended to limit the embodiments. Other variations and modifications will be apparent to persons skilled in the art in light of the above description. And are neither required nor exhaustive of all embodiments. And obvious variations or modifications therefrom are within the scope of the invention.

Claims

1. The preparation method of the electrode current collector is characterized by comprising the following steps:

placing a first roller to be roughened at a set position;

repeatedly controlling the laser texturing system to horizontally move relative to the first roller to be textured, so that the distance between two adjacent first axial texturing points is x1, until a first axial anchor point group parallel to the axis of the first roller to be textured is formed on the circumference of the first roller to be textured;

controlling the first roller to be roughened to rotate to a first circumferential texturing point, wherein the circumferential distance between the first circumferential texturing point and the corresponding first axial texturing point is y1, controlling the first roller to be roughened to horizontally move by taking the first circumferential texturing point as a starting point, and forming the first axial anchor point group in the horizontal direction;

repeatedly controlling the first roller to be roughened to rotate, wherein the distance between every two adjacent first circumferential texturing points is y1, and forming the first axial anchor point group by taking the corresponding first circumferential texturing points as starting points;

selecting a second roller to be roughened, which has the same size as the first roller to be roughened, and repeating the step of preparing the first roller to be roughened to obtain a second roller to be roughened;

controlling the first texturing roller to rotate relative to the second texturing roller, wherein the relative rotation distance is (y1-a)/2, and a is the diameter of the first texturing point;

and drawing the foil to be rolled out from the unwinding end, rolling the foil through a rolling gap between the first texturing roller and the second texturing roller, controlling the rolling mill to press down, simultaneously starting the rolling mill, the unwinding equipment and the winding equipment, adjusting a tension control device, and gradually adjusting the rolling speed and the unwinding speed.

2. The electrode current collector preparation method according to claim 1, further comprising:

the method comprises the steps of oppositely grinding, namely measuring the surface roughness Ra, Rz and Rt of the bimetal roller, controlling the first texturing roller and the second texturing roller to be arranged in parallel, enabling a transverse anchor point group to be staggered front and back, controlling the outer surfaces of the first texturing roller and the second texturing roller to be in contact with each other and to be pressed down, controlling a pressing-down gap to be 1-5 times of Ra, and starting a rolling mill to oppositely grind the textured bimetal roller;

3. The electrode current collector preparation method of claim 2, wherein (y1+ a) is divisible by the roll circumference (pi x d), wherein d is the diameter of the first roll to be textured.

4. The method for preparing an electrode current collector as claimed in any one of claims 1 to 3, wherein the thickness of the foil to be rolled is 2 to 20 μm.

5. The method for preparing an electrode current collector as claimed in claim 4, wherein the foil to be rolled is subjected to a pressure of 5-100 Mpa.

6. An electrode current collector obtained by the production method according to any one of claims 1 to 5.