CN210467983U

CN210467983U - Splicing forming lithium belt

Info

Publication number: CN210467983U
Application number: CN201921243065.3U
Authority: CN
Inventors: 谢斌; 陈仕通; 龚志杰
Original assignee: Contemporary Amperex Technology Co Ltd
Current assignee: Contemporary Amperex Technology Co Ltd
Priority date: 2019-08-02
Filing date: 2019-08-02
Publication date: 2020-05-05
Anticipated expiration: 2029-08-02

Abstract

The utility model discloses a concatenation shaping lithium area. The spliced lithium belt is formed by splicing more than two basic lithium belts; wherein the thickness fluctuation of the base lithium band is 5% or less; the spliced and formed lithium belt is provided with splicing areas and non-splicing areas which are alternately distributed along the splicing direction, and the maximum thickness H of the splicing areas and the minimum thickness L of the non-splicing areas meet the following requirements:

the utility model provides a splice shaping lithium area can compromise great width and good thickness uniformity simultaneously.

Description

Splicing forming lithium belt

Technical Field

The utility model belongs to the technical field of energy memory, concretely relates to concatenation shaping lithium area.

Background

Along with the popularization of new energy automobiles, the endurance mileage requirement of power batteries is higher and higher. Meanwhile, consumer electronics such as mobile phones are increasingly popularized and diversified, and an important experience feeling of a user is the service time after one-time charging. Therefore, the demand for high energy density secondary batteries is increasingly desired.

Increasing the electrode width increases the capacity of the cell. To achieve higher energy density, the anode (also called negative electrode) may be prelithiated. There are many ways of prelithiation, one of which employs metallic lithium ribbons. For example, a lithium metal strip is rolled to obtain a pre-lithium-doped lithium foil, and the lithium foil is in contact with or laminated on the negative electrode film layer, so that the lithium metal foil pre-lithiates the negative electrode active material under the action of a potential difference. However, the lithium ribbons currently in common use are of small width and do not meet the requirements of wide electrode prelithiation well. Therefore, it is urgently needed to develop a wide lithium ribbon to meet the market demand.

SUMMERY OF THE UTILITY MODEL

The inventor finds that if the width of the metal lithium strip is directly increased, namely, the wide lithium strip is prepared in a one-step forming mode, the thickness consistency of the wide lithium strip in the TD (Transverse Direction) Direction is poor. When the lithium strip is used for pre-supplementing lithium foil, lithium strip accumulation is easy to occur in the production process, continuous production is not facilitated, and the production efficiency and the excellent rate are seriously influenced; meanwhile, when the obtained lithium foil is used for anode pre-lithium supplement, the uniformity of anode pre-lithium intercalation is poor, and the cycle performance of the battery is affected.

The inventors of the present invention have conducted extensive studies and have skillfully found that a wide lithium ribbon having good thickness uniformity can be obtained by splicing and molding two or more narrow lithium ribbons as a base lithium ribbon.

Therefore, the utility model provides a splicing molding lithium belt, which is formed by splicing more than two basic lithium belts; wherein the content of the first and second substances,

the thickness variation of the base lithium band is less than 5%;

the spliced and formed lithium belt is provided with splicing areas and non-splicing areas which are alternately distributed along the splicing direction, and the maximum thickness H of the splicing areas and the minimum thickness L of the non-splicing areas meet the following requirements:

according to the utility model discloses an aspect, the splice area includes that the body is regional and transition region, and the transition region of each splice area is adjacent with non-splice area, and the width that each body is regional is 0.1mm ~ 3.5mm, preferably 1mm ~ 3 mm.

According to the utility model discloses an aspect, the splice area includes along two relative bulges of the thickness direction of concatenation shaping lithium area, and two bulges do not bulge in two ascending surfaces of non-splice area in thickness direction, and each bulge is trapezoidal or type of trapezoidal in the transversal trapezoidal or type of personally submitting of thickness direction, and each trapezoidal or type of trapezoidal angle of going to the bottom is below 0.02 degree.

According to one aspect of the present invention, the lower base angle is 2 × 10^-3Degree of less than or equal to, preferably 1X 10^-4Degree of 2X 10^-3And (4) degree.

According to an aspect of the present invention, the thickness fluctuation of the basic lithium ribbon is 3% or less, preferably 2.5% or less.

According to the utility model discloses an aspect, satisfy between the minimum thickness L of the biggest thickness H of splice area and non-splice area:

according to an aspect of the present invention, the width of the basic lithium ribbon is 170mm or less, preferably 80mm to 160mm, and more preferably 80mm to 130 mm.

According to an aspect of the present invention, the thickness of the basic lithium belt is 0.2mm to 4mm, preferably 0.5mm to 3mm, and more preferably 1mm to 2 mm.

According to the utility model discloses an aspect, concatenation shaping lithium area is for being spliced the shaping each other by the basic lithium area more than two in self width direction, and splice area and non-splice area distribute in concatenation shaping lithium area self width direction in turn.

According to the utility model discloses an aspect to concatenation shaping lithium area self width direction ascending side border is the benchmark, and the body is regional within 1mm in the ascending position fluctuation of width direction.

Compared with the prior art, the utility model discloses following beneficial effect has at least:

the utility model discloses a mode of basic lithium area concatenation to the thickness of control basic lithium area is undulant and the thickness difference of splice area and non-splice area is in specific range, and great width and good thickness uniformity can be compromise simultaneously in the concatenation shaping lithium area that obtains.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required to be used in the embodiments of the present invention will be briefly described below, and for those skilled in the art, other drawings can be obtained according to these drawings without creative efforts.

Fig. 1 is a schematic cross-sectional view of a splicing region of a spliced lithium ribbon according to an embodiment of the present invention.

Fig. 2 is a graph showing the thickness variation of the splice-molded lithium ribbon of example 21 and the wide lithium ribbon of comparative example 1.

Detailed Description

In order to make the objects, technical solutions and advantageous technical effects of the present invention clearer, the present application is described in detail with reference to specific embodiments below. It should be understood that the embodiments described in this specification are only for the purpose of explaining the present application and are not intended to limit the present application.

For the sake of brevity, only some numerical ranges are explicitly disclosed herein. However, any lower limit may be combined with any upper limit to form ranges not explicitly recited; and any lower limit may be combined with any other lower limit to form a range not explicitly recited, and similarly any upper limit may be combined with any other upper limit to form a range not explicitly recited. Also, although not explicitly recited, each point or individual value between endpoints of a range is encompassed within the range. Thus, each point or individual value can form a range not explicitly recited as its own lower or upper limit in combination with any other point or individual value or in combination with other lower or upper limits.

In the description herein, it is to be noted that, unless otherwise specified, "above" and "below" are inclusive and "one or more" of "the" means "two or more.

The above summary of the present invention is not intended to describe each disclosed embodiment or every implementation of the present invention. The following description more particularly exemplifies illustrative embodiments. At various points throughout this application, guidance is provided through a list of embodiments that can be used in various combinations. In each instance, the list is merely a representative group and should not be construed as exhaustive.

The embodiment of the utility model provides a concatenation shaping lithium area. The spliced lithium belt is formed by splicing more than two basic lithium belts. Wherein the thickness fluctuation of the base lithium band is less than 5%; the spliced and formed lithium belt is provided with splicing areas and non-splicing areas which are alternately distributed along the splicing direction, and the maximum thickness H of the splicing areas and the minimum thickness L of the non-splicing areas meet the following requirements:

the inventor skillfully discovers that the spliced forming lithium belt obtained by adopting the mode of splicing the basic lithium belt and controlling the thickness fluctuation of the basic lithium belt and the thickness difference between the spliced area and the non-spliced area to be within a specific range can simultaneously take large width and good thickness consistency into consideration.

Herein, the maximum thickness of the base lithium ribbon in the TD direction is denoted as L₁And the minimum thickness of the base lithium strip in the TD direction is recorded as L₂The design thickness of the base lithium strip (i.e., the thickness specification of the base lithium strip) is designated as L₀The thickness fluctuation of the base lithium band is (L)₁-L₂)/L₀X is 100 percent, and A satisfies A is less than or equal to 5 percent.

The maximum and minimum thickness of the base lithium strip can be determined using instruments and methods known in the art. For example, a micrometer or a micrometer is used to measure the base from one side edge of the base lithium belt in the width direction (i.e., TD direction) to the opposite side edge at a predetermined intervalThickness values of the lithium strips. The preset spacing may be selected by a person skilled in the art according to the requirement of test accuracy. The predetermined pitch is, for example, 1mm to 30mm, such as 5mm to 20 mm. The maximum of the measured thickness values can be recorded as L₁The minimum value can be noted as L₂。

The utility model discloses a concatenation shaping lithium area is formed by the concatenation of the basic lithium area more than two, like two, three, four or more. Specifically, the edges of two adjacent basic lithium strips are laminated with each other, and the obtained spliced and formed lithium strip comprises a splicing area and a non-splicing area along the splicing direction. The thickness fluctuation of the basic lithium belt is less than 5%, so that the non-splicing area of the spliced and formed lithium belt has higher thickness consistency, and the thickness fluctuation of the splicing area of the spliced and formed lithium belt is smaller.

Herein, the maximum dimension of the splicing region in the thickness direction of the spliced and formed lithium tape is the maximum thickness H of the splicing region. The minimum size of the non-splicing region in the thickness direction of the spliced lithium strip is the thickness L of the non-splicing region. The relationship between the maximum thickness H of the splicing region and the minimum thickness L of the non-splicing region is denoted as B ═ H-L |/lx 100%. That is, B may represent the thickness deviation of the spliced region and the non-spliced region of the spliced and formed lithium tape, and at the same time, B also represents the thickness uniformity of the spliced and formed lithium tape. B is less than or equal to 6 percent, so that the fluctuation influence of the thickness of the splicing region on the whole thickness of the spliced and formed lithium belt is small, and the thickness consistency of the spliced and formed lithium belt is obviously improved.

The value of B can be determined using instruments and methods known in the art. For example, a micrometer or a micrometer is used to measure the thickness of the lithium ribbon at predetermined intervals from one side edge of the lithium ribbon to the other side edge of the lithium ribbon in the width direction (i.e., TD direction). The preset spacing may be selected by a person skilled in the art according to the requirement of test accuracy. The predetermined pitch is, for example, 1mm to 30mm, such as 5mm to 20 mm. The measured thickness values include a plurality of thickness values of the splicing region and a plurality of thickness values of the non-splicing region. Wherein the plurality of thickness values of the splicing region comprises a plurality of thickness values of the body region (see the following description for details). The maximum value of the thickness values of the body region of the splicing region is recorded as H, and the minimum value of the thickness values of the non-splicing region is recorded as L.

If A is less than or equal to 5% and B is less than or equal to 6%, the whole spliced lithium belt has good thickness consistency.

In some preferred embodiments, the thickness variation A of the base lithium strip satisfies A.ltoreq.3%, more preferably A.ltoreq.2.5%, more preferably A.ltoreq.1.5%. The thickness fluctuation of the basic lithium belt is small, and the thickness consistency of the spliced and formed lithium belt obtained after splicing is better.

The utility model discloses an among the concatenation shaping lithium area, preferably, the thickness in basic lithium area is below 4 mm. The thickness of the basic lithium belt is proper, so that the spliced lithium belt has smaller thickness while the thickness consistency is better. This better meets the application requirements for prelithiation of the anode in a battery.

Alternatively, the thickness of the base lithium strip may be 10 μm or more, 100 μm or more, 200 μm or more, 300 μm or more, 500 μm or more, 800 μm or more, 1mm or more, 1.2mm or more; the thickness of the base lithium tape may be 4mm or less, 3.5mm or less, 3mm or less, 2.5mm or less, 2mm or less, 1.5mm or less.

Preferably, the thickness of the basic lithium ribbon is 0.2mm to 4 mm. More preferably, the thickness of the base lithium tape is 0.5mm to 3 mm. More preferably, the thickness of the base lithium tape is 1mm to 2 mm.

Optionally, the width of the base lithium strip is 170mm or less. The width of the basic lithium belt influences the thickness consistency of the basic lithium belt, and further influences the thickness consistency of the spliced lithium belt. The base lithium belt has proper width, so that the base lithium belt can obtain better thickness consistency, and the spliced and formed lithium belt with better thickness consistency is obtained.

In some embodiments, the width of the base lithium band may be 10mm or more, may be 30mm or more, may be 50mm or more, may be 60mm or more, may be 70mm or more, may be 80mm or more, and may be 90mm or more. The width of the base lithium tape may be 170mm or less, may be 160mm or less, may be 150mm or less, may be 140mm or less, may be 130mm or less, may be 120mm or less, may be 110mm or less, and may be 100mm or less.

Preferably, the width of the base lithium band is 160mm or less. The spliced lithium belt has better thickness consistency by adopting the basic lithium belt.

To obtain a wider ribbon of spliced shaped lithium, a suitably wide base lithium ribbon may be used. Therefore, the number of the basic lithium strips needing to be spliced is small, namely the number of the splicing areas is small, and the influence of the thickness deviation of the splicing areas on the thickness consistency of the whole spliced and formed lithium strip can be reduced. Therefore, the obtained spliced lithium belt is large in width and good in thickness consistency, and the thickness fluctuation of the whole spliced lithium belt is smaller.

In some preferred embodiments, the width of the base lithium band is 80mm to 160 mm. More preferably, the width of the basic lithium ribbon is 80mm to 130 mm. The base lithium belt can enable the spliced lithium belt to obtain better thickness consistency.

The utility model discloses an among the concatenation shaping lithium area, preferably, the mohs hardness in basic lithium area is 0.6 ~ 2.5. When the Mohs hardness of the basic lithium strip is 0.6-2.5, the fluidity of metal is good in the pressing (such as rolling) process, the pressing operation is convenient, and the splicing strength is high. Particularly, the Mohs hardness of the basic lithium strip is 0.6-2.5, and the uniformity of metal flowing is good in the pressing (such as rolling) process, so that the thickness consistency of the spliced lithium strip can be further improved.

More preferably, the Mohs hardness of the basic lithium ribbon is 0.6-2.0. More preferably, the Mohs hardness of the basic lithium ribbon is 0.6 to 1.5. More preferably, the Mohs hardness of the basic lithium ribbon is 0.6 to 1.0.

The utility model discloses an in the concatenation shaping lithium area, basic lithium area can be for metal lithium area or lithium alloy area. The lithium alloy ribbon is based on metal lithium and added with a modifying element, so that the Mohs hardness of the basic lithium ribbon can be adjusted. For example, the modifying element may be one or more selected from Al, Mg, Na, K, Ca, Si, Pb, Fe, Ni, and Cu.

Further, the mass percentage of metallic lithium in the lithium alloy ribbon is 80% or more, and more preferably 90% or more. The lithium alloy strip has high content of metal lithium, and when the lithium alloy strip is used for the anode prelithiation, the effect of the anode prelithiation can be improved, so that the energy density of the battery can be improved.

The mohs hardness of the base lithium strip can be measured using instruments and methods known in the art. Such as a mohs hardness scale.

In some preferred embodiments, B ≦ 5% is satisfied between the maximum thickness H of the stitching region and the minimum thickness L of the non-stitching region. The smaller the thickness deviation of the splicing area and the non-splicing area of the spliced and formed lithium belt is, the better the thickness consistency of the whole spliced and formed lithium belt is.

The utility model discloses a concatenation shaping lithium area is including concatenation district and non-concatenation district. Specifically, the edges of two adjacent basic lithium strips are mutually laminated and integrated through a laminating layer. Under the pressure of lamination, the thickness of the lamination area is reduced, and the metal in the lamination area flows to the other edge direction of the two basic lithium strips opposite to the lamination edge, so that each splicing area of the finally formed spliced and formed lithium strip comprises a body area and transition areas positioned on two sides of the body area. The transition area of each splicing area is adjacent to the non-splicing area. Specifically, one side of the transition region, which is far away from the body region, is a non-splicing region. Referring to fig. 1, the thicknesses of the non-splicing regions are substantially the same; the thickness of the body area of the splicing area is basically consistent, and the thickness of the transition area is in a decreasing thickness gradient from the body area to the non-splicing area.

The smaller the splicing width of two adjacent basic lithium belts is, the smaller the influence of the thickness deviation of the splicing region on the thickness consistency of the spliced forming lithium belt is. The utility model discloses an among the concatenation shaping lithium area, the width in body region is equal to the range upon range of width that the edge of two adjacent basic lithium areas was range upon range of each other before the lamination basically, consequently can embody the size of concatenation width through the width in body region. When the width of each body region is less than 3.5mm, a spliced lithium belt with high thickness consistency can be obtained.

In some embodiments, the width of each body region can be 3.5mm or less, 3mm or less, 2.8mm or less, 2.5mm or less, 2.3mm or less, 2mm or less, 1.8mm or less, 1.5mm or less. The width of each body region may be 0.1mm or more, 0.3mm or more, 0.5mm or more, 0.7mm or more, 0.9mm or more, 1.0mm or more, 1.1mm or more.

Preferably, the width of each body region is 0.1mm to 3.5 mm. More preferably, each body region has a width of 1mm to 3 mm. The width of each body region is proper, so that the spliced lithium strip has high splicing strength and mechanical property while having high thickness consistency.

Further, the splicing region comprises two protrusions which are opposite to each other in the thickness direction of the spliced and formed lithium strip. The two convex parts respectively protrude out of two surfaces of the non-splicing area in the thickness direction of the spliced lithium strip. That is, one of the convex parts protrudes from the surface of one side of the non-splicing region in the thickness direction of the spliced lithium strip, and the other convex part protrudes from the surface of the other side of the non-splicing region opposite to the surface of the one side.

The cross section of each protruding part in the thickness direction of the spliced lithium strip is trapezoidal or trapezoid-like. The regions corresponding to the upper bottom of the trapezoid or the trapezoid-like shape are body regions of the splicing region, and the regions corresponding to the two side waists of the trapezoid or the trapezoid-like shape are transition regions of the splicing region respectively. In some preferred embodiments, the lower base angle θ of the trapezoid or trapezoid-like shape is 0.02 degrees or less, preferably 2 × 10^-3Not more than about 1X 10, more preferably 1X 10^-4Degree of 2X 10^-3And (4) degree.

The section angle theta in splicing area is appropriate, and then the thickness uniformity influence of splicing area's horizontal thickness change to splicing shaping lithium area is less, can further improve splicing shaping lithium area's thickness uniformity.

The determination of the bottom base angle θ of the splice area can be performed using instruments and methods known in the art. The lower base angle θ can be determined, for example, by the following method: taking a spliced and formed lithium belt sample, and cutting the sample to obtain the cross section of the sample; measuring the size of the transition region in the width direction of the spliced forming lithium strip and recording the size as l₁Measuring the size of the convex part in the thickness direction of the spliced forming lithium strip and recording the size as l₂(ii) a θ is then calculated according to the following equation:

in some embodiments, the base lithium strip is a strip, and the base lithium strip is spliced along the width direction of the spliced and formed lithium strip. Namely, the spliced lithium strip is formed by splicing more than two basic lithium strips in the width direction of the lithium strip, and the spliced areas and the non-spliced areas are alternately distributed in the width direction of the spliced lithium strip. The thickness consistency of the spliced lithium belt is high on the whole.

Further, the position fluctuation of the body region in the width direction is within 1mm by taking the side edge of the splicing molding lithium belt in the width direction as a reference.

The positional fluctuation of the splicing region in the width direction can be measured by the following method comprising: testing the distance between one side edge of the body region and the edge of the spliced lithium strip on the same side or the opposite side by a dimension measuring tool (such as a flexible rule and the like, wherein the testing precision is 0.1mm for example), and testing a numerical value at intervals of 0.2-0.5 m (the testing interval can be adjusted by a person skilled in the art according to requirements) in the length direction of the spliced lithium strip; the difference between the maximum value and the minimum value of the plurality of values obtained by the test is less than or equal to 1 mm. Since the luminance of the body region after lamination is larger than that of the other regions, the edges of the body region can be distinguished conveniently.

The position fluctuation of the body region is within 1mm, namely the splicing region is a straight line region along the length direction of the spliced and formed lithium strip basically. The integral thickness consistency of the spliced lithium belt is further improved.

When the Mohs hardness of the basic lithium belt is 0.6-2.5, preferably 0.6-2.0, preferably 0.6-1.5, and more preferably 0.6-1.0, the lower bottom angle theta of the splicing region can meet the requirements. In addition, when the Mohs hardness of the basic lithium belt is 0.6-2.5, preferably 0.6-2.0, preferably 0.6-1.5, and more preferably 0.6-1.0, the position fluctuation of the body area of the splicing area is favorably within 1 mm.

It can be understood that, in the splicing molding lithium strip of the utility model, there is no special restriction on the shape of the basic lithium strip and the splicing direction thereof. The basic lithium ribbon may be any shape, such as triangular, quadrilateral, pentagonal, irregular polygonal, etc. The splicing direction of the basic lithium belt can be along the width direction or the length direction of the spliced and formed lithium belt, or the splicing direction of the basic lithium belt can be any other direction.

The spliced shaped lithium tape as described above can be obtained by the following production method. The method comprises the following steps:

and S10, providing more than two basic lithium belts, wherein the thickness fluctuation of each basic lithium belt is less than 5%.

In step S10, the base lithium ribbon may be a metallic lithium ribbon or a lithium alloy ribbon. The lithium alloy ribbon may be the one described above.

In step S10, the thickness fluctuation of the base lithium ribbon is preferably 3% or less, more preferably 2.5% or less.

In step S10, the width of the base lithium tape is preferably 170mm or less, preferably 80mm to 160mm, and more preferably 80mm to 130 mm.

In step S10, the Mohs hardness of the basic lithium ribbon is preferably 0.6-2.5, preferably 0.6-2.0, preferably 0.6-1.5, and more preferably 0.6-1.0.

In step S10, the thickness of the base lithium ribbon is preferably 0.2mm to 4mm, more preferably 0.5mm to 3mm, and still more preferably 1mm to 2 mm.

In this context, the base lithium tapes are either commercially available or can be prepared using methods known in the art. As an example of a method for preparing the basic lithium ribbon, a first substrate, a lithium sheet to be rolled, and a second substrate may be sequentially stacked and rolled by a rolling device to laminate the three; the second substrate is then peeled off. In the laminated structure, two sides of the lithium sheet to be rolled are completely covered by the first base material and the second base material respectively.

The first substrate can be a polymer membrane, a metal membrane or an inorganic material membrane. For example, the first substrate may employ one or more of teflon, polyethylene, polypropylene, polyurethane, polytetrafluoroethylene, polyarylsulfone, polyethylene glycol terephthalate, acrylonitrile-butadiene-styrene copolymer, polyimide, and polyethersulfone.

The second substrate can be a polymer membrane, a metal membrane or an inorganic material membrane. For example, the second substrate may employ one or more of teflon, polyethylene, polypropylene, polyurethane, polytetrafluoroethylene, polyarylsulfone, polyethylene glycol terephthalate, acrylonitrile-butadiene-styrene copolymer, polyimide, and polyethersulfone.

In the process of rolling the laminated structure of the first base material, the lithium sheet to be rolled and the second base material by using a rolling device, the heating temperature of the working roll is 35-120 ℃ for example; the rolling pressure is between 0.2MPa and 1.5 MPa; the speed of the working roll is between 0.001m/min and 60 m/min; the gap between the work rolls may be greater than 0 and 5mm or less.

And S20, splicing more than two basic lithium belts in sequence to enable the edges of two adjacent basic lithium belts to be mutually overlapped, and pressing to obtain the spliced and formed lithium belt.

In step S20, two or more basic lithium strips are sequentially spliced, wherein the edges of every two adjacent basic lithium strips are stacked on each other, and the width of the stack is preferably 3.5mm or less, more preferably 0.1mm to 3mm, and still more preferably 1mm to 3 mm. And pressing the spliced basic lithium belts, so that the laminated edges of every two adjacent basic lithium belts are mutually laminated into a whole.

In step S20, the pressing process may be performed by using a device and method known in the art, such as a rolling device. The temperature of the pressing can be normal temperature, such as 20-30 ℃, and further such as 20-25 ℃. The pressure of lamination may be adjusted according to the material, thickness, etc. of the base lithium tape. For example, in some embodiments, the pressure of lamination can be 0.9 tons to 2 tons, such as 1 ton to 1.5 tons.

In some embodiments, at step S20, two or more basic lithium tapes may be sequentially spliced in the width direction thereof.

In some embodiments, step S20 includes:

and S210, splicing more than two basic lithium belts in sequence along the width direction of the basic lithium belts, and enabling the edges of two adjacent basic lithium belts to be mutually laminated and the laminating width to be less than or equal to 3.5 mm.

In step S210, edges of adjacent two basic lithium strips are stacked one on another and the stacking width is preferably 0.1mm to 3.5mm, more preferably 1mm to 3 mm.

S220, correcting the deviation of more than two spliced basic lithium belts, and taking the outer side edge of the outermost basic lithium belt as a reference, wherein the position fluctuation of a laminated area in the width direction of the mutually laminated edges of two adjacent basic lithium belts is within 1 mm.

The positional fluctuation in the width direction of the laminated region where the edges of two adjacent base lithium strips are laminated to each other can be measured by a method including: testing the distance between one side edge of the laminated region of two adjacent basic lithium strips and the outer side edge of the outermost basic lithium strip by a dimension measuring tool (such as a flexible rule, a CCD image sensor and the like, the testing precision is 0.1mm for example), and testing a numerical value every 0.2-0.5 m (the testing interval can be adjusted by a person skilled in the art according to requirements) in the length direction of the basic lithium strips; the difference between the maximum value and the minimum value of the plurality of values obtained by the test is less than or equal to 1 mm. The outermost base lithium tape may be the same side or a different side of the outermost base lithium tape from the one side edge of the lamination region. The outer side edge of the outermost side basic lithium belt is correspondingly spliced to form the outer side edge of the lithium belt.

The position fluctuation of the laminated regions of two adjacent basic lithium strips in the width direction is within 1mm, so that the spliced and formed lithium strips are based on the side edge in the width direction, and the position fluctuation of the body region in the width direction is within 1mm, so that the obtained spliced and formed lithium strips have better overall thickness consistency.

In step S220, the correction may be performed by using a correction sensor or the like.

And S230, rolling more than two spliced basic lithium belts to obtain spliced and formed lithium belts.

In step S230, rolling may be performed using an apparatus and method known in the art, such as a rolling apparatus. The rolling temperature may be normal temperature, such as 20-30 deg.C, and further such as 20-25 deg.C. The pressure of the rolling may be 0.9 to 2 tonnes, such as 1 to 1.5 tonnes.

According to the preparation method, after the basic lithium belt is spliced, the spliced and formed lithium belt with large width and good thickness consistency can be obtained through pressing. The preparation method has high operability, and can improve production efficiency and reduce production cost. In addition, the wide lithium band with good thickness consistency is prepared by the preparation method, and higher production goodness can be obtained. Therefore, the utility model discloses when improving the thickness uniformity in broad width lithium area, still solved among the prior art the great metal lithium area of direct processing width's production goodness extremely low, the high problem of production and processing cost.

Examples

The present disclosure is more particularly described in the following examples that are intended as illustrative only, since various modifications and changes within the scope of the present disclosure will be apparent to those skilled in the art. Unless otherwise indicated, all parts, percentages, and ratios reported in the following examples are on a weight basis, and all reagents used in the examples are commercially available or synthesized according to conventional methods and can be used directly without further treatment, and the equipment used in the examples is commercially available.

Example 1

The guodi lithium strip is obtained by the roll forming method described above, and serves as a basic lithium strip. Wherein the width of the basic lithium ribbon is 80mm, the design thickness is 2mm, and the thickness fluctuation A in the TD direction is 1%.

The edges of the two basic lithium strips were laminated to each other with a lamination width of 1 mm. The two basic lithium tapes were then laminated by rolling to a width of 159mm as a spliced lithium tape, the rolling pressure being 1.5 tons. The thickness fluctuation of the non-spliced region of the spliced lithium belt in the TD direction is 1%, and the B value of the spliced lithium belt is 2%.

Example 2

Similar to example 1, except that the width of the base lithium ribbon was 100mm, the thickness variation in the TD direction was 1.3%, and the remaining parameters are detailed in table 1.

Example 3

Similar to example 1, except that the width of the base lithium ribbon was 130mm, the thickness variation in the TD direction was 1.5%, and the remaining parameters are detailed in table 1.

Example 4

Similar to example 1, except that the width of the base lithium ribbon was 140mm, the thickness variation in the TD direction was 2.0%, and the remaining parameters are detailed in table 1.

Example 5

Similar to example 1, except that the width of the base lithium ribbon was 160mm, the thickness variation in the TD direction was 3.0%, and the remaining parameters are detailed in table 1.

Example 6

Similar to example 1, except that the width of the base lithium ribbon was 170mm, the thickness variation in the TD direction was 5.0%, and the remaining parameters are detailed in table 1.

Example 7

Similar to example 3, except that the mohs hardness of the base lithium tape was 0.8, the remaining parameters are detailed in table 1.

Example 8

Similar to example 3, except that the mohs hardness of the base lithium tape was 1.0, the remaining parameters are detailed in table 1.

Example 9

Similar to example 3, except that the mohs hardness of the base lithium tape was 1.2, the remaining parameters are detailed in table 1.

Example 10

Similar to example 3, except that the mohs hardness of the base lithium tape was 2, the remaining parameters are detailed in table 1.

Example 11

Similar to example 3, except that the mohs hardness of the base lithium tape was 2.5, the remaining parameters are detailed in table 1.

Example 12

Similar to example 3, except that the width of the edges of the two base lithium strips stacked on each other was 0.1mm, the remaining parameters are detailed in table 1.

Example 13

Similar to example 3, except that the width of the edges of the two basic lithium strips stacked on each other was 2mm, the remaining parameters are detailed in table 1.

Example 14

Similar to example 3, except that the width of the edges of the two basic lithium strips stacked on each other was 3mm, the remaining parameters are detailed in table 1.

Example 15

Similar to example 3, except that the width of the edges of the two base lithium strips stacked on each other was 3.5mm, the remaining parameters are detailed in table 1.

Example 16

Similar to example 3, except that the base lithium tape was designed to have a thickness of 0.2mm and a thickness variation in TD direction of 3%, the remaining parameters are detailed in table 1.

Example 17

Similar to example 3, except that the base lithium tape was designed to have a thickness of 0.5mm and a thickness variation in TD direction of 2.5%, the remaining parameters are detailed in table 1.

Example 18

Similar to example 3, except that the base lithium tape was designed to have a thickness of 1mm and thickness variation in TD direction of 1.7%, the remaining parameters are detailed in table 1.

Example 19

Similar to example 3, except that the base lithium tape was designed to have a thickness of 3mm and thickness variation in TD direction of 1.3%, the remaining parameters are detailed in table 1.

Example 20

Similar to example 3, except that the base lithium tape was designed to have a thickness of 4mm and a thickness variation in TD direction of 1.1%, the remaining parameters are detailed in table 1.

Example 21

Similar to example 3, except that the rolling pressure was 0.9 ton, the remaining parameters are detailed in Table 1.

Comparative example 1

The lithium sheet was rolled and a wide lithium ribbon of 259mm width and 2mm design thickness was directly processed by one-shot forming with 23% thickness variation (measured according to the method for measuring the thickness variation of the basic lithium ribbon), with the remaining parameters detailed in table 1. The mohs hardness of the lithium sheet for preparing the wide lithium tape was 0.6.

Comparative example 2

Similar to example 1, except that the width of the base lithium ribbon was 180mm, the thickness variation in the TD direction was 5.5%, and the remaining parameters are detailed in table 1.

Comparative example 3

Similar to example 3, except that the thickness variation of the base lithium strip was 10%, the remaining parameters are detailed in table 1.

Test section

(1) Width of basic lithium belt (Flexible rule, precision 0.1mm)

(2) Thickness (micrometer, precision 0.001mm)

(3) Hardness of basic lithium belt (Mohs hardness tester)

(4) Width of splicing zone body zone (tape, precision 0.1mm)

(5) Splicing shaped lithium belt width (flexible rule, precision 0.1mm)

TABLE 1

In table 1, the overall thickness variation of the spliced lithium tapes in examples 1 to 21 and comparative examples 2 to 3 was equal to the thickness deviation B.

Can know by embodiment 1 ~ 21 and comparative example 1 ~ 3's comparison, the utility model discloses a mode of basic lithium area concatenation to the thickness deviation B of the thickness fluctuation A of control basic lithium area and splice area and non-splice area is in specific range, and great width and good thickness uniformity can be compromise simultaneously in the concatenation molding lithium area that obtains.

In contrast, in comparative example 1, the wide lithium ribbon was directly formed in one step, and the wide lithium ribbon had large thickness variation and poor thickness uniformity (as shown in fig. 2). The thickness of the basic lithium tapes of comparative examples 2 and 3 fluctuates greatly, which also results in poor thickness uniformity of the spliced wide lithium tapes.

From the results of examples 1 to 6 and comparative example 2, it is found that when the width of the base lithium ribbon is 170mm or less, the thickness fluctuation is generally small, and the thickness uniformity of the spliced lithium ribbon can be improved.

From the results of examples 3 and 7 to 11, it is found that when the hardness of the base lithium tape is 0.6 to 2.5, the thickness uniformity of the spliced lithium tape is improved.

From the results of examples 3, 12 to 15, it is understood that when the lamination width of the base lithium tape is 3.5mm or less, the thickness uniformity of the spliced lithium tape can be improved.

From the results of examples 3 and 16 to 20, it can be seen that the thickness of the base lithium tape affects the thickness fluctuation thereof, and further affects the thickness uniformity of the spliced lithium tape. The thickness of the basic lithium belt is less than 4mm, and when the thickness fluctuation is less than 5%, the thickness consistency of the spliced and formed lithium belt is improved.

From the results of example 3 and example 21, it is known that the rolling pressure on the spliced basic lithium ribbon affects the thickness uniformity of the spliced lithium ribbon. The rolling pressure in example 21 was small, resulting in a large thickness of the spliced region, and the thickness uniformity of the obtained spliced shaped lithium ribbon was relatively reduced.

While the invention has been described with reference to specific embodiments, the scope of the invention is not limited thereto, and those skilled in the art can easily conceive various equivalent modifications or substitutions within the technical scope of the invention. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims

1. A spliced lithium belt is characterized in that more than two basic lithium belts are spliced and formed; wherein the content of the first and second substances,

the thickness variation of the base lithium strip is less than 5%;

2. the spliced lithium belt of claim 1, wherein the spliced regions comprise body regions and transition regions, the transition regions of the spliced regions are adjacent to the non-spliced regions, and the width of the body regions is 0.1mm to 3.5 mm.

3. The spliced shaped lithium tape of claim 2, wherein the width of each body region is 1mm to 3 mm.

4. The spliced lithium belt according to any one of claims 1 to 3, wherein the spliced area comprises two opposite protrusions in the thickness direction of the spliced lithium belt, the two protrusions respectively protrude from two surfaces of the non-spliced area in the thickness direction, the cross section of each protrusion in the thickness direction is trapezoidal or trapezoid-like, and the lower base angle of each trapezoidal or trapezoid-like is less than 0.02 degrees.

5. The spliced shaped lithium tape of claim 4, wherein the lower base angle is 2 x 10^-3Degree below.

6. The spliced shaped lithium tape of claim 4, wherein the lower base angle is 1 x 10^-4Degree of 2X 10^-3And (4) degree.

7. The spliced shaped lithium tape of claim 1, wherein the thickness variation of the base lithium tape is 3% or less.

8. The spliced shaped lithium tape of claim 1, wherein the thickness variation of the base lithium tape is 2.5% or less.

9. The spliced shaped lithium ribbon of claim 1, wherein the maximum thickness H of the spliced region and the minimum thickness L of the non-spliced region satisfy:

10. the spliced shaped lithium strip of claim 1, wherein the width of the base lithium strip is 170mm or less.

11. The spliced shaped lithium ribbon of claim 1, wherein the width of the base lithium ribbon is 80mm to 160 mm.

12. The spliced shaped lithium tape of claim 1, wherein the width of the base lithium tape is 80mm to 130 mm.

13. The spliced shaped lithium tape of claim 1, wherein the base lithium tape has a thickness of 0.2mm to 4 mm.

14. The spliced shaped lithium tape of claim 1, wherein the base lithium tape has a thickness of 0.5mm to 3 mm.

15. The spliced shaped lithium tape of claim 1, wherein the base lithium tape has a thickness of 1mm to 2 mm.

16. The spliced lithium strip according to claim 2 or 3, wherein the spliced lithium strip is formed by splicing more than two basic lithium strips in the width direction of the spliced lithium strip, and the spliced regions and the non-spliced regions are alternately distributed in the width direction of the spliced lithium strip.

17. The spliced shaped lithium ribbon of claim 16, wherein the positional fluctuation of the body region in the width direction is within 1mm with reference to the side edges in the width direction of the spliced shaped lithium ribbon itself.