Laminated films of alkali metal or alloy thereof, and apparatus for making the same

Abstract

To provide laminated films of an alkali metal or an alloy thereof, and an apparatus for making the same.SOLUTION: A working roller for a rolling mill for laminating a sheet of an alkali metal or alloy thereof to a film is disclosed. The working roller has: a cylindrical center portion defining a central axis, and having an outer surface defining a lamination surface; and first and second frustoconical portions extending from first and second ends of the center portion, respectively. When the central axis is straight, an angle between the outer surface of the center portion and an outer surface of each of the first and second frustoconical portions is less than 0.05°. A width of the center portion is greater than a width of each of the first and second frustoconical portions. The width of the center portion is less than the sum of the widths of the first and second portions. A rolling mill having two such working rollers is also disclosed. A laminated sheet of an alkali metal or alloy thereof obtained by the working roller of the present technology is also disclosed.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] [CROSS-REFERENCE TO RELATED APPLICATIONS] This application claims the benefit of U.S. Provisional Application No. 62 / 936,806, filed November 18, 2019, and U.S. Provisional Application No. 62 / 936,809, filed November 18, 2019, and U.S. Provisional Application No. 62 / 936,814, filed November 18, 2019, the disclosures of all of which are incorporated by reference in their entireties herein.

[0002] The present technology relates to a work roller for a rolling mill for laminating a sheet of an alkali metal or its alloy to a film, and to a rolling mill having such a work roller, and also to a laminated film of an alkali metal or its alloy obtained from a rolling mill including such a work roller. [Background technology]

[0003] Secondary batteries made from laminates of solid polymer electrolytes and thin film anodes and cathodes offer many advantages over conventional liquid electrolyte batteries, including reduced overall battery weight, high specific energy, long life, and environmental protection by eliminating the risk of toxic liquids being released into the environment.

[0004] The components of a solid polymer battery include a positive electrode, a negative electrode, and an insulating material capable of allowing ionic conduction, such as a solid polymer electrolyte sandwiched between the electrodes. The anode or negative electrode is usually made of a lightweight metal film, such as an alkali metal and its alloy, e.g., lithium metal, lithium aluminum alloy. The composite cathode or positive electrode is usually formed of a mixture of an active material, such as a transition metal oxide, a conductive filler, usually carbon particles, an ion-conducting polymer electrolyte material, and a current collector, usually a thin sheet of aluminum. The composite cathode thin film is usually obtained by coating on the current collector.

[0005] Producing thin films of lithium having thicknesses below 100 microns, in wide strips, e.g., 10 centimeters or more, and hundreds of meters long, by rapid and reliable processes faces significant technical difficulties due to the extreme physical and chemical properties of this metal, such as chemical reactivity, malleability, low mechanical strength, rapid self-welding by simple contact, and strong adhesion to most solid materials.

[0006] Cold extrusion is used for the continuous production of sheets above 100 microns. These thicknesses are generally adapted for the manufacture of lithium cells utilizing liquid electrolytes. For thicknesses below that, the film obtained by extrusion is then laminated between working rollers made of a hard material.

[0007] The difficulties in achieving efficient lamination of high density lithium to thicknesses that vary between 20 and 100 microns for the fabrication of polymer electrolyte cells in large scale production processes are numerous.

[0008] Laminated lithium metal often reacts with and / or deforms and adheres to the working rollers it comes in contact with during the lamination process. This problem can be solved by using a lubricant such as those described in U.S. Patent Nos. 5,399,433, 5,443,614, 5,514,715, 5,621,131, and 5,791,625, all of which are incorporated herein by reference. The lubricant contains additives that prevent the thin laminated lithium film from reacting with or excessively adhering to the working rollers, and does not affect the electrochemical properties of the resulting electrochemical cell. However, it is desirable to properly and efficiently apply the lubricant during the lamination process.

[0009] The extremely high ductility of lithium or its alloys allows for very little drawing tension on the lithium film as it leaves the work rollers, and therefore the drawing tension must be precisely monitored and controlled to prevent breakage or tearing of the lithium film and the resulting costly production interruptions.

[0010] At thicknesses between 20 and 100 microns, it is difficult to laminate a lithium or alloy film to a consistent thickness across the entire width of the film and over the extended length of the film. Conventional lamination processes result in thickness variations across the width of the laminated lithium film, which promotes breakage of the lithium film during the lamination operation and makes the resulting laminated lithium film unsuitable for electrochemical cells.

[0011] The working rollers are traditionally made of polyacetal, a hard plastic material that is compatible with (i.e., does not react with) lithium. However, in mass production, polyacetal rollers wear out quickly, necessitating frequent replacement or disposal of worn rollers, significantly increasing costs. This has made the lamination manufacturing process economically unfeasible.

[0012] Thus, what is needed is a mill adapted for laminating a sheet of an alkali metal or its alloy to a film that addresses at least some of the above problems. There is also a need for an alkali metal film produced by such a mill that maintains desirable properties across the width and length of the film. [Prior art documents] [Patent documents]

[0013] [Patent Document 1] U.S. Patent No. 5,837,401 [Patent Document 2] U.S. Patent No. 5,528,920 [Patent Document 3] U.S. Patent No. 6,019,801 Summary of the Invention [Problem to be solved by the invention]

[0014] The objective of the present technology is to ameliorate at least some of the disadvantages present in the prior art. [Means for solving the problem]

[0015] Some embodiments of the present technology relate to a laminated lithium or lithium alloy film obtained by a rolling mill, the rolling mill comprising a frame; a first working roller rotatably mounted to the frame; a second working roller rotatably mounted to the frame, the first and second working rollers being positioned to receive a sheet therebetween; at least two first actuators operably connected to opposite ends of the first working roller to bend the first working roller; and at least two second actuators operably connected to opposite ends of the second working roller to bend the second working roller. each of the first and second working rollers includes a cylindrical central portion defining a central axis, the cylindrical central portion having an outer surface defining a lamination surface; a first frusto-conical portion extending from a first end of the central portion; and a second frusto-conical portion extending from a second end of the central portion; wherein when the central axis is straight, an angle between the outer surface of the central portion and the outer surfaces of each of the first and second frusto-conical portions is less than 0.05 degrees, and a width of the central portion is greater than a width of each of the first and second frusto-conical portions and the width of the central portion is less than a sum of the widths of the first and second portions.

[0016] According to various aspects, the present technology relates to a laminated lithium or lithium alloy film obtained by a rolling mill including a working roller having a cylindrical central portion defining a central axis and having an outer surface defining a lamination surface; a first frusto-conical portion extending from a first end of the central portion; and a second frusto-conical portion extending from a second end of the central portion; wherein when the central axis is straight, an angle between the outer surface of the central portion and the outer surfaces of each of the first and second frusto-conical portions is less than 0.05 degrees, and a width of the central portion is greater than a width of each of the first and second frusto-conical portions and the width of the central portion is less than a sum of the widths of the first and second portions.

[0017] According to various aspects, the present technology relates to a lithium or lithium alloy film comprising a metal element, the metal element being present in the lithium or lithium alloy film in an amount of at least 3000 ppm; the lithium or lithium alloy film being at least about 1×10 -4 ~Approx. 7×10 -4 The thickness to width ratio is between 0.01 and 0.1.

[0018] According to various aspects, the present technology relates to a laminated lithium or lithium alloy film comprising at least about 3000 ppm aluminum, the laminated lithium or lithium alloy film having a thickness, width and length, the thickness to width ratio being about 1×10 -4 ~Approx. 7×10 -4 and is uniform throughout the length of the lithium or lithium alloy film.

[0019] For the purposes of this application, surface roughness is provided in meters, specifically the roughness average (Ra) expressed in microns, and angles are expressed in degrees (i.e., 360 degrees for a full revolution). For the purposes of this application, hardness describes the resistance of materials (e.g., sheets and films) to localized deformation, which deformation is induced either by mechanical indentation or abrasion. For the purposes of this application, tensile strength (TS) refers to the ability of materials (e.g., sheets and films) to exhibit a tendency to stretch when subjected to a load. Tensile strength is measured by the maximum stress that a material can withstand when stretched or pulled before breaking.

[0020] The term "about" is used herein, whether expressly or not; all amounts given herein are meant to refer to the actual given value, and also to approximations of such given value, including equivalents and approximations by experimental and / or measurement conditions to such given value that would be reasonably inferred based on the skilled artisan. For example, the term "about" in the context of a given value or range means a value or range that is within 20%, preferably within 15%, more preferably within 10%, more preferably within 9%, more preferably within 8%, more preferably within 7%, more preferably within 6%, and more preferably within 5% of the given value or range.

[0021] Each embodiment of the present technology will have at least one, but not necessarily all, of the above-mentioned objects and / or aspects, and it will be understood that some aspects of the present technology, which result from attempting to achieve the above-mentioned object, may not meet that object and / or may meet other objects not specifically described herein.

[0022] Additional and / or alternative features, aspects, and advantages of embodiments of the present technology will become apparent from the following description, the accompanying drawings, and the appended claims.

[0023] For a better understanding of the present technology, as well as other aspects and further features thereof, reference is made to the following description taken in conjunction with the accompanying drawings, in which: [Brief description of the drawings]

[0024] [Figure 1] FIG. 1 is a schematic cross-sectional side view of a rolling mill and associated components for laminating lithium or lithium alloy sheets into thin films. [Diagram 2] FIG. 2 is a schematic side elevational view showing the major components of the rolling mill of FIG. 1 that allow control of the thickness and shape of the laminated lithium or lithium alloy film. [Diagram 3] FIG. 3 is a schematic front elevational view showing the major components of the rolling mill of FIG. [Figure 4A] FIG. 4A is a schematic front elevational view of the backup rollers and work rollers of the rolling mill of FIG. 2 shown in different alignments, with the angle of the frustoconical portion of the work rollers and the degree of bending of the work rollers exaggerated for illustrative purposes. [Figure 4B] FIG. 4B is a schematic front elevational view of the backup rollers and work rollers of the rolling mill of FIG. 2 shown in different alignments, with the angle of the frustoconical portion of the work rollers and the degree of bending of the work rollers exaggerated for illustrative purposes. [Figure 4C] FIG. 4C is a schematic front elevational view of the backup rollers and work rollers of the rolling mill of FIG. 2 shown in different alignments, with the angle of the frustoconical portion of the work rollers and the degree of bending of the work rollers exaggerated for illustrative purposes. [Diagram 5] FIG. 5 is a front elevational view of one work roller of the rolling mill of FIG. 2; [Figure 6A] FIG. 6A is a close-up view of portion 6 of FIG. 5 according to one embodiment of the roller of FIG. [Figure 6B] 6B is a close-up view of portion 6 of FIG. 5 according to another embodiment of the roller of FIG. [Figure 7] FIG. 7 is a schematic cross-sectional profile of a lithium or lithium alloy sheet fed to the rolling mill of FIG. [Figure 8] FIG. 8 is a perspective view of a lamination lubricant distribution unit for lubricating the upper work rollers of the rolling mill of FIG. [Figure 9] FIG. 9 is a perspective view of a lamination lubricant distribution unit for lubricating the lower work roller of the rolling mill of FIG. [Figure 10] FIG. 10 is a top view of the lamination lubricant dispensing unit of FIG. [Figure 11] FIG. 11 is a front elevational view of the lamination lubricant dispensing unit of FIG. [Figure 12] 12 is a cross-sectional view of the lamination lubricant dispensing unit of FIG. 9 taken through line 12-12 of FIG. [Figure 13]FIG. 13 is a close-up view of portion 13 of FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0025] 1 illustrates generally a rolling mill 10 and associated components adapted to produce lithium or lithium alloy thin films 12 of less than 100 microns thickness from pre-extruded lithium or lithium alloy sheets 14 of approximately 100-500 microns thickness. Although embodiments of the present technology are described with respect to producing lithium or lithium alloy thin films 12 from lithium or lithium alloy sheets 14, it is envisioned that at least some aspects of the present technology may be used to produce other alkali metal or alkali metal alloy thin films from other alkali metal or alkali metal alloy sheets.

[0026] The rolling mill 10 includes a main frame 16, a pair of work rollers 18a and 18b, a backup roller 20a adjacent to and in contact with the work roller 18a, a backup roller 20b adjacent to and in contact with the work roller 18b, a lamination lubricant distribution unit 22 for distributing lubricant to the work roller 18a, and a lamination lubricant distribution unit 200 for distributing lubricant to the work roller 18a. As can be seen, the work roller 18a is disposed below the work roller 18b. The work rollers 18a, 18b and the lamination lubricant distribution units 22, 200 will be described in more detail below. The work rollers 18a, 18b and the backup rollers 20a, 20b are rotatably mounted on support frames 50 and 52 (FIG. 2) as described in more detail below.

[0027] The roll 24 of wound extruded lithium or lithium alloy sheet 14 is placed on a feed roller 26 including a drive motor control unit (not shown) adapted to control the tension of the lithium sheet 14 before it reaches the work rollers 18a and 18b. The sheet 14 snakes through a series of free rollers 28 leading to an encoder roller 41 which measures the exact speed of the traveling sheet 14, and a tension roller 43 equipped with a load cell adapted to measure the exact tension of the sheet 14 entering the lamination apparatus 10. The load cell of the tension roller 43 is electronically coupled to the control unit of the drive motor of the roll 24 so that the tension applied to the sheet 14 can be automatically adjusted. The sheet 14 is then fed to a straightener 30 which rapidly winds the sheet 14 through a series of tight rollers 32 which have the effect of eliminating lateral displacement of the sheet 14 and preventing zigzag motion of the sheet 14, thereby ensuring that the sheet 14 is fed straight into the central portion of the work rollers 18a and 18b without lateral weaving motions that are detrimental to the lamination process. Thus, sheet 14 is fed to work rollers 18a and 18b at a fixed position between rollers 18a, 18b.

[0028] At the inlet of the rolling mill 10, the lubricant distribution units 22 and 200 dispense a suitable amount of lithium-compatible lamination lubricant onto the working surface of each of the work rollers 18a and 18b upstream of the lamination area so that the sheet 14 is laminated with the appropriately lubricated work rollers 18a and 18b, thereby preventing undesired adhesion of the laminate film 12 to either of the work rollers 18a, 18b. One suitable lubricant is described in U.S. Pat. No. 5,837,401 and U.S. Pat. No. 6,019,801, which are incorporated herein by reference in their entirety. In one embodiment, the lubricant is based on toluene, hexane, and polyoxyethylene distearate and is used in sufficient amount on each of the work rollers 18a and 18b to prevent excessive adhesion of the laminate film 12 to either of the work rollers.

[0029] The sheet 14 passes between two working rollers 18a and 18b where its thickness is reduced from about 100-500 microns to about 20-100 microns depending on the desired final thickness of the film 12. Pressure is applied to the working rollers 18a and 18b by the backup rollers 20a and 20b, thereby providing sufficient pressure to the sheet 14 to reduce its thickness and transform it into the film 12. Lamination pressure is applied through the backup rollers 20a and 20b, rather than directly to the working rollers 18a and 18b, to help avoid unwanted bending of the working rollers 18a and 18b, which would be reflected in the shape and thickness of the film 12. As will be described below, to produce a quality thin film 12, the surface roughness of the working rollers 18a and 18b should be minimal. The pressure applied by the backup rollers 20a and 20b to the working rollers 18a and 18b is distributed evenly over the surface of each roller 18a and 18b, thereby leaving the shape of the working rollers 18a and 18b undisturbed. However, if the working rollers 18a and 18b are sufficiently rigid, the pressure required to reduce the thickness of the sheet 14 and transform it into the film 12 can be applied directly by the working rollers 18a and 18b without the use of backup rollers. It is also envisioned that multiple backup rollers can be used to apply equal pressure to each of the working rollers 18a and 18b. For example, two pairs of backup rollers can be placed on either side of the working rollers 18a and 18b.

[0030] The laminate film 12 is pulled through an optical fireproofing system 36 that measures the surface uniformity of the film 12 and also detects voids on the film 12 and cracks along the edges of the film 12. The optical system can also be used to measure the thickness of the film 12. A controlled tension is applied to the film 12 by a driven take-up roller 38 to ensure that the film 12 is properly wound. Before reaching the take-up roller 38, the laminate film 12 snakes through a series of rollers under controlled tension. The first of these rollers is a tension roller 45 equipped with a load cell adapted to precisely measure the tension on the laminate film 12 as it exits the rolling mill 10. The load cell of the tension roller 45 is electronically coupled to a control unit for the drive motor of the take-up roller 38 so that the tension applied to the sheet 12 can be automatically adjusted. The film 12 then passes over an encoder roller 47 that measures the exact speed of the film 12 as it travels. The film 12 then passes through a series of free rollers 34 that lead to the take-up roller 38.

[0031] A thin insulating film 90, such as a polypropylene film, is also wound on the take-up roller 38 to separate the layers of the film 12 so that they do not stick to each other. The insulating film 90 is pulled by the take-up roller 38 from a roll 92. From the roll 92, the insulating film 90 reaches the roller 38 after passing over a tension roller 94. The tension roller 94 is equipped with a load cell adapted to accurately measure the tension in the insulating film 90. This tension measurement is used to control the tension exerted by the take-up roller 38 on the film 12, since the tension exerted by the take-up roller 38 is divided between the film 12 and the insulating film 90.

[0032] Encoder rollers 41 and 47 measure the velocity of sheet 14 entering mill 10 and the velocity of laminate film 12 exiting mill 10, respectively. The relationship between the inlet velocity of sheet 14 and the outlet velocity of laminate film 12 is directly proportional to the amount of thickness reduction from the initial sheet 14 to the film 12. In this manner, if the thickness of the initial sheet 14 is known, the thickness of laminate film 12 can be mathematically determined. Thus, the thickness of laminate film 12 is controlled and verified through the speed difference between the velocities measured by encoder rollers 41 and 47. It is envisioned that the thickness of laminate film 12 may be controlled and verified in different ways.

[0033] In one embodiment, the lamination process is carried out in an anhydrous atmosphere containing less than 1% relative humidity to prevent undesirable chemical reactions between the lithium film 12 and water particles that would render the lithium film 12 unsuitable for use in an electrochemical cell.

[0034] 2 and 3, the major components of the rolling mill 10 that allow for control of the thickness and shape of the laminated film 12 will now be described. It should be understood that the illustrated rolling mill 10 is one exemplary embodiment of a rolling mill adapted to control the shape and thickness of the laminated film 12, and that other embodiments are contemplated. For example, the support members and frames may have different configurations, and various hydraulic system configurations may be used.

[0035] The backup rollers 20a and 20b are rotatably mounted on bearings in support frames 50 and 52, respectively. The support frame 52 is slidably mounted on the vertical member of the main frame 16 via any suitable means, such as a sliding channel or bearings. The support frame 50 is fixedly mounted on the vertical member of the main frame 16. Thus, the support frame 52 can move vertically. The work rollers 18a and 18b are driven by electric or hydraulic motors (not shown), respectively. The work rollers 18a, 18b frictionally drive the backup rollers 20a and 20b. A pair of hydraulic linear actuators 66 are mounted on the upper horizontal member of the main frame 16. The hydraulic actuators are connected to the support frame 52. The hydraulic linear actuators 66 control the up and down movement of the support frame 52 and the pressure applied to the work rollers 18a and 18b. The work rollers 18a and 18b are rotatably mounted on support members 54 and 56, respectively. Support members 54 and 56 are operably connected to support frames 50 and 52, respectively. Ends 58 and 59 of support member 54 are operably connected to support frame 50 via a pair of hydraulic linear actuators 60 and 61, and ends 62 and 63 of support member 56 are operably connected to support frame 52 via a pair of hydraulic linear actuators 64 and 65.

[0036] In operation, the speed of lamination is set by the speed of the working rollers 18a and 18b. The pressure P required to reduce the thickness of the film 12 to the desired thickness is adjusted through a hydraulic valve controlling the hydraulic linear actuator 66. The backup roller 20b transmits the pressure P to the working roller 18b. Once the desired pressure P is set, the final shape of the laminate film 12 is fine-tuned by adjusting the fluid pressure to each of the hydraulic linear actuators 60, 61, 64 and 65, and thereby the force that each of the hydraulic linear actuators 60, 61, 64 and 65 exerts on the support members 54 and 56, as described in more detail below. The hydraulic linear actuators 60, 61, 64, 65 and 66 may be replaced by other types of actuators capable of generating sufficient force, for example electric actuators. In an alternative embodiment, additional hydraulic linear actuators are connected between the support members 54, 56. In such an embodiment, hydraulic linear actuators 60, 61, 64, 65 and 66 are used to urge support members 54, 56 towards each other and additional hydraulic linear actuators are used to urge support members 54, 56 towards each other.

[0037] During the lamination process, heat builds up on the working rollers 18a and 18b due to friction occurring at the lamination surfaces, which has the effect of slightly expanding the working rollers 18a and 18b. Expansion of the working rollers 18a, 18b of a few microns in the lamination area is sufficient to produce a film 12 of uneven thickness unsuitable for a thin film electrochemical cell. To alleviate this problem and help ensure a film 12 of uniform thickness, the central portion 100 (FIG. 4A) of the expanded working rollers 18a and 18b is adjusted by bending the working rollers 18a and 18b, straightening the central portion 100 and producing a lithium film 12 of uniform thickness. This control process is described below with reference to FIGS. 4A-4C. It should be noted that the shapes of the work rollers 18a and 18b illustrated in Figures 4A-4C have been greatly exaggerated for clarity, but it will be understood that the tapering and curved profiles of the ends of the work rollers 18a, 18b are not visible to the naked eye as they actually represent merely micron deviations from a perfectly straight profile.

[0038] 4A shows working rollers 18a and 18b in a neutral position, with backup rollers 20a and 20b exerting sufficient pressure P on working rollers 18a and 18b to reduce the thickness of sheet 14 to the desired thickness of film 12, while no lateral force is applied to support members 54 and 56 of working rollers 18a, 18b.

[0039] In FIG. 4b, the backup rollers 20a and 20b still exert a pressure P on the working rollers 18a and 18b sufficient to reduce the thickness of the sheet 14 to the desired thickness of the film 12. However, due to thermal expansion, the central portions of the working rollers 18a and 18b expand due to the accumulation of heat generated by the friction of the central portions 100 against the sheet 14. To compensate for this thermal expansion, which has deformed the working rollers 18a and 18b, an inwardly directed lateral force Fx is applied to the support members 54 and 56. The lateral force Fx bends the working rollers 18a and 18b slightly outward, thereby flattening the central portions 100 as depicted in FIG. 4B. The outer edges of the working rollers 18a and 18b are bent inward to straighten the central portions 100. The resulting laminate film 12 is therefore flat and has a uniform thickness. Additionally, the thermal expansion of the work rollers 18a, 18b is partially counteracted by the application of a lamination lubricant to the work rollers 18a, 18b, and it is contemplated that additional means for cooling the work rollers 18a, 18b may be used to help counteract the thermal expansion of the work rollers 18a, 18b.

[0040] If the edges of the sheet 14 to be laminated are thicker than its center, more pressure is applied by the working rollers 18a, 18b to the outer edges of the sheet 14, and thus to the outer edges of the center portion 100, in order to laminate the film 12 with a uniform thickness over its width. To this end, the same lateral force Fx is applied to the support members 54 and 56, thereby bending the outer edges of the working rollers 18a, 18b slightly inward, applying more pressure to the edges of the sheet 14 than to its center portion. As a result, the laminate film 12 has a uniform thickness over its width. As heat accumulates in the working rollers 18a, 18b due to friction of the center portion 100 against the sheet 14, the center portions of the working rollers 18a, 18b expand only slightly. To compensate for this thermal expansion, which causes the diameter of the central portions of the work rollers 18a and 18b to increase only slightly, the lateral force Fx is proportionally reduced to keep the central portions 100 straight and ensure that the resulting laminate film 12 has a uniform thickness across its entire width.

[0041] Sometimes, the center portion of the sheet 14 being laminated may be thicker than its edges. In order to laminate the film 12 with a uniform thickness across its width, more pressure needs to be applied by the working rollers 18a and 18b to the center portion of the sheet 14, and thus the center portion of the central portion 100. To do so, an outwardly directed lateral force Fy is applied to the support members 54 and 56, as shown in FIG. 4c. The lateral force Fy causes the center portions of the working rollers 18a and 18b to bend slightly inwardly, forcing the center portion of the central portion 100 inwardly, thereby applying more pressure to the center portion of the sheet 14 and laminating the film 12 with a uniform thickness across its entire width.

[0042] In some circumstances, heat generated by friction of the central portion 100 against the sheet 14 accumulates on the outer portions of the meeting surfaces of the working rollers 18a and 18b, causing them to expand, resulting in a small gap opening in the center of the central portion 100. To compensate for this thermal expansion, an outwardly directed lateral force Fy is applied to the support members 54 and 56 of the working rollers 18a and 18b. The lateral force Fy bends the central portion of the central portion 100 slightly inward, straightening the central portion 100. The profile of the central portion 100 of the working rollers 18a, 18b is bent back into a straight line so that the resulting laminate film 12 is flat and has a uniform thickness across its entire width.

[0043] 4B and 4C only show symmetrical adjustment of the work rollers 18a, 18b, but other adjustments are possible because the support members 54 and 56 are independent of each other. For example, if the work rollers 18a, 18b expand more on one side than the other, the left or right support member 54, 56 may have a force Fx or Fy that exceeds the force Fx or Fy of the opposite support member 54, 56 so that a large amount of fine adjustment is possible.

[0044] By combining control of the shape of the central portion 100 with precise measurements from a suitable measuring device, such as the optical fireproofing system 36, the rolling mill 10 is able to produce a quality laminate film 12 in the range of thicknesses from 20 to 100 microns, exhibiting a nearly constant thickness over its entire length and width.

[0045] Adjustments to the profile and thickness of the laminate film 12 are performed by an on-site operator who fine-tunes the pressure applied by the backup rollers 20a and 20b and the pressure applied to the support members 54 and 56, or this may be performed electronically by linking the measurement readings and the actuators that control the various pressures and forces of the backup rollers 20a, 20b and the work rollers 18a, 18b to a computer that makes real-time adjustments to these parameters.

[0046] 5 to 6B, the work roller 18a will be described in more detail. In this embodiment, the work roller 18b is identical to the work roller 18a, and therefore the work roller 18b will not be described separately herein. It is envisioned that the work roller 18b may differ in parts from the work roller 18a.

[0047] As previously mentioned, the work roller 18a has a central portion 100. The central portion 100 is cylindrical. The outer surface 102 of the central portion 100 defines a lamination surface against which the sheets 14 roll during the lamination process. As such, the central portion 100 has a width W1 that is slightly greater than the width W2 (FIG. 7) of the sheets 14 being laminated. The central portion 100 defines a central axis 104 of the work roller 18a.

[0048] From the end of the central portion 100, a frustoconical portion 106 extends. The frustoconical portions 106 are mirror images of each other. In FIG. 5, the outer surface 110 of the frustoconical portion 106 appears not to taper. This is because the tapering angle is very small and invisible to the naked eye. This angle is exaggerated in FIGS. 6A and 6B showing two different embodiments of the working roller 18a and will be described below. Each frustoconical portion 106 has a width W3. The width W1 of the central portion 100 is greater than the width W3 of each frustoconical portion 106. The width W1 of the central portion 100 is less than the sum of the widths W3 of both frustoconical portions 106 (i.e., W1 < W3 + W3). In one embodiment, the width W1 is between 125 mm and 210 mm, and the width W3 is between 65 mm and 110 mm.

[0049] In one embodiment shown in FIG. 6A, the frusto-conical portions 106 taper as they extend away from the central portion 100. This embodiment is shown in FIGS. 4A-4C where the tapering is exaggerated. In this embodiment, a shoulder 108 is defined between the central portion 100 and each frusto-conical portion 106 (shown for one frusto-conical portion in FIG. 6A). In some embodiments, the shoulder 108 has a height H1 that is less than 0.05 mm. In some embodiments, the height H1 is less than 0.02 mm. It is contemplated that the shoulder 108 may be omitted. When the central axis 104 is straight (i.e., when the work roller 18a is in a neutral position as in FIG. 4A), the angle A between the outer surface 102 of the central portion 100 and the outer surface 110 of the frusto-conical portion 106 is less than 0.05 degrees. In some embodiments, the angle A is less than 0.03 degrees. In some embodiments, the angle A is less than 0.02 degrees. In some embodiments, the angle A is less than 0.02 degrees but more than 0.01 degrees. In some embodiments, the central portion 100 has a diameter D1 between 70 mm and 90 mm. In some embodiments, the difference between the minimum diameter D2 and the maximum diameter D3 of each frustoconical portion 106 is between 0.03 mm and 0.17 mm. The profile of the working rollers 18a and 18b according to the present embodiment facilitates bending of the central portion 100 by providing a free zone 84 (FIG. 4A) between the frustoconical portions 106 and a free zone 85 (FIG. 4A) between the frustoconical portions 106 and the backup rollers 20a and 20b so that the ends of the working rollers 18a and 18b can be moved to bend the central portion 100 as desired. The free zones 84 also allow excess lamination lubricant to drain laterally during the lamination process. Although the embodiment of work roller 18a shown in FIG. 6A can be used with sheets 14 having many different profiles due to the adjustments that can be made in rolling mill 10 (as described above with respect to FIGS. 4A-4C), this embodiment of work roller 18a is particularly well suited for laminating extruded sheets 14 with a central portion 112 having a height H2 (FIG. 7) that is less than the height H3 (FIG. 7) of its side portions 114.Again, in Figure 7, heights H2 and H3 do not appear to be different because the difference is not visible to the naked eye. In some embodiments, height H2 is less than 15 microns less than height H3.

[0050] In another embodiment shown in FIG. 6B, each frusto-conical portion 106 tapers as it extends from its outer end toward the central portion 100 (i.e., D2 is greater than D3). When the central axis 104 is straight (i.e., when the work roller 18a is in a neutral position), the angle B between the outer surface 102 of the central portion 100 and the outer surface 110 of the frusto-conical portion 106 is less than 0.05 degrees. In some embodiments, the angle B is less than 0.03 degrees. In some embodiments, the angle B is less than 0.02 degrees. In some embodiments, the angle B is less than 0.02 degrees but greater than 0.01 degrees. In some embodiments, the central portion 100 has a diameter D1 between 70 mm and 90 mm. In some embodiments, the difference between the maximum diameter D2 and the minimum diameter D3 of each frusto-conical portion 106 is between 0.03 mm and 0.17 mm. While the embodiment of work roller 18a shown in Figure 6B can be used with sheets 14 having many different profiles due to adjustments that can be made in rolling mill 10 (as discussed above with respect to Figures 4A-4C), this embodiment of work roller 18a is particularly well suited for laminating sheets 14 extruded with a center portion 112 having a height H2 (Figure 7) that is greater than the height H3 (Figure 7) of its sides 114. In some embodiments, height H2 is less than 15 microns greater than height H3.

[0051] Returning to Figure 5, work roller 18a has support shafts 116, 118 extending from the ends of frusto-conical portion 106. Support shafts 116, 118 are received in bearings (not shown) for rotatably mounting work roller 18a to support member 54 (or to support member 56 for work roller 18b). Support shaft 118 has an extension 120 adapted for connection to a motor which drives work roller 18b. Portions 100, 106 and support shafts 116, 118 are integrally formed.

[0052] As previously mentioned, the lamination lubricant dispensed on the work rollers 18a, 18b helps prevent adhesion of the lithium film 12 to the work rollers 18a, 18b so that the film 12 exits the work rollers 18a, 18b in a straight line. The use of the lubricant allows lithium and lithium alloys to be laminated with work rollers 18a, 18b made from materials that are not normally suitable for adhesion with lithium. The lubricant negates this constraint. Thus, for large scale production, the work rollers 18a, 18b are preferably made from a durable hard material such as steel or stainless steel or ceramic. In some embodiments, the steel or stainless steel rollers 18a, 18b have a thin chrome coating to increase hardness. The chrome coating is applied on at least the center and frustoconical portions 100, 106 of the work rollers 18a, 18b. In some embodiments, the chrome coating is a hard chrome coating. To provide a desired surface finish to the film 12 and to allow for some adhesion of the lamination lubricant onto the work rollers 18a, 18b, in some embodiments, the outer surfaces 102, 110 of the central and frusto-conical portions 100, 106 have a surface roughness in the range between 0.025 microns Ra and 0.5 microns Ra. In other embodiments, the surface roughness is in the range between 0.05 microns Ra and 0.30 microns Ra.

[0053] Turning now to FIG. 8, the lamination lubricant distribution unit 22 will be described in more detail. The lamination lubricant distribution unit 22 includes four nozzles 150 mounted on a rail 152. It is envisioned that the lamination lubricant distribution unit 22 may have more or less than four nozzles 150. Lamination lubricant is supplied to a passageway (not shown) within the rail 152 via a suction connector 154. The suction connector 154 is fluidly connected to a pump (not shown) that supplies lubricant to the suction connector 154 from a lubricant reservoir (not shown) that holds the lamination lubricant therein. The four nozzles 150 are in fluid communication with the passageway within the rail 152. As seen in FIG. 1, the lamination lubricant distribution unit 22 is positioned upstream of the lamination region and spaced apart from the work roller 18b. The lamination lubricant dispensing unit is positioned above the central axis 104 of the work roller 18b and is angled such that the nozzle 150 continuously sprays lamination lubricant onto the lamination surface of the work roller 18b. The spray from the nozzle 150 covers an area slightly larger than the lamination surface.

[0054] Each nozzle 150 has a nozzle body 156, a filter, a nozzle head 158, and a nut 160. The nozzle body 156 is threaded onto the rail 152. The filter is disposed within the nozzle body 156. The nozzle head 158 defines a spray opening 162 and is disposed at the end of the nozzle body 156. The nut 160 is disposed over and threaded into the nozzle body 156 to maintain the nozzle head 158 and filter in place.

[0055] 9-13, the lamination lubricant dispensing unit 200 will be described. In this embodiment, the lamination lubricant dispensing unit 200 is made from a single piece of static dissipative acetal copolymer. It is contemplated that other types of materials may be used, such as polyamide, polypropylene, polyethylene, acrylonitrile butadiene styrene, polyethylene terephthalate, polystyrene, thermoplastic polyurethane, poly(methyl methacrylate), polyvinyl chloride, brass, and aluminum. Other materials are also contemplated. It is also contemplated that the lamination lubricant dispensing unit 200 may be made from multiple pieces bonded or otherwise connected together.

[0056] The lamination lubricant distribution unit 200 includes a distribution unit body 202. Each rear corner of the distribution unit body 202 defines two openings 206. The openings 206 receive fasteners (not shown) for securing the distribution unit body 202 to the frame 16 of the rolling mill 10 at a location between the work roller 18a and the straightener 30. The distribution unit body 202 defines a laterally extending wall 208. As best seen in FIG. 12, a single lubricant passage 210 is defined in the distribution unit body 202. The lubricant passage 210 has an inlet (not shown) defined in a rear wall 214 of the distribution unit body 202 and an outlet 216 defined in the laterally extending wall 208. As can be seen, the outlet 216 is laterally centered and located at the bottom of the laterally extending wall 208. It is envisioned that multiple lubricant passages 210 may be defined within the dispensing unit body 202, with outlets of these passages at different locations along the laterally extending wall 208. It is also envisioned that at least some of the multiple lubricant passages 210 may have a common inlet.

[0057] Two side walls 218 extend forwardly from the laterally extending wall 208. As can be seen in Figure 10, the side walls 218 are parallel to one another. As can be seen in Figure 12, the front ends 220 of the side walls 218 are angled from the vertical so as not to interfere with the work rollers 18a.

[0058] The lamination lubricant distribution unit 200 also has a ledge 222. The ledge 222 is connected to and extends forwardly from a lower end of the laterally extending wall 208. The ledge 222 is also connected to and extends between a lower end of the side wall 218. The ledge 222, the side wall 218, and the laterally extending wall 208 together define an open-sided recess 224 at the front of the lamination lubricant distribution unit 200. The ledge 222 has a leading edge 226 that contacts the lamination surface of the work roller 18a at a location vertically below the central axis 104 of the work roller 18a, as seen in FIG. 12. The leading edge 226 has a width W4 (FIG. 10) that is greater than the width W1 of the lamination surface of the work roller 18a to help ensure that the lamination lubricant is applied across the entire width of the lamination surface.

[0059] 13, the ledge 222 has an angled portion 228 that extends upwardly and rearwardly from a leading edge 226 toward the laterally extending wall 208. A corner 230 between the angled portion 228 and the leading edge 226 is arcuate. In some embodiments, the angled portion 228 extends at an angle C between 5 and 25 degrees from the horizontal. In some embodiments, the angle C is between 10 and 20 degrees from the horizontal. The ledge 222 also has a generally horizontal portion 232 that extends between the angled portion 228 and the laterally extending wall 208. The portion 232 is horizontal when viewed from the side (i.e., when viewed in FIGS. 12 and 13). However, when viewed from the front of the portion 232 (i.e., when viewed in FIG. 11), the portion 232 slopes slightly downwardly on either side of its lateral center, such that the lateral center corresponds to the apex of the portion 232. In some embodiments, the angle D (FIG. 11) between the surfaces on either side of the lateral center of the portion 232 is greater than 180 degrees but less than 185 degrees, and in some embodiments less than 182 degrees. It is also contemplated that the portion 232 may be flat (i.e., angle D is 180 degrees) when viewed from a front view of the portion 232 (i.e., as viewed in FIG. 11). As can be seen in FIGS. 11 and 12, the outlet 216 of the lubricant passage 210 is laterally aligned with the apex of the portion 232, and the bottom of the outlet 216 is vertically aligned with the top of the portion 232 of the ledge 222 adjacent thereto. It is contemplated that the portion 232 may be omitted and the angled portion 228 may extend from the leading edge 226 to the laterally extending wall 208.

[0060] A laterally extending gutter 234 is defined in angled portion 228 of ledge 222. As best seen in FIG. 10, an end of gutter 234 is spaced from sidewall 218. Gutter 234 is spaced from leading edge 226 of ledge 222. As can be seen in FIG. 13, gutter 234 is closer to leading edge 226 than portion 232 of ledge 222.

[0061] 12, the inlet of the lubricant passage 210 is fluidly connected to a pump 236, which is itself fluidly connected to a lubricant reservoir 238. The lubricant reservoir 238 holds lamination lubricant therein. It is envisioned that the lubricant reservoir 238 may also be used to supply lamination lubricant to the lamination lubricant distribution unit 22 described above. The pump 236 pumps lamination fluid from the lubricant reservoir 238 into the lubricant passage 210. From the outlet 216 of the lubricant passage 210, the lubricant flows forward and laterally (due to angle D) along the portion 232 of the ledge. The lubricant then flows downward along the angled portion 228. A portion of the lubricant flows into a gutter 234, which helps ensure an even distribution of the lubricant across the width of the ledge 222. The lubricant then flows to the leading edge 226 where it contacts the lamination surface of the work roller 18a. The lamination surface moving over the work roller 18 a picks up lubricant which effectively coats the lamination surface in contact with the sheet 14 .

[0062] In some embodiments, the alkali metal or alkali metal alloy film of the present technology is a laminated lithium film or a laminated lithium alloy film obtained using a rolling mill and working rollers as defined herein.

[0063] Lithium alloys that can be used to prepare the films of the present technology include, but are not limited to: lithium-silicon, lithium-aluminum, lithium-magnesium, lithium-strontium, lithium-barium, and the like.

[0064] The lithium or lithium alloy film of the present technology includes an amount of a metal element. The addition of a metal element to the lithium or lithium alloy film can reduce the overall thickness of the film and improve its overall mechanical strength. In some embodiments, the metal element is present in the lithium or lithium alloy film in an amount that improves the mechanical strength throughout the width, thickness and length of the film.

[0065] The metal element that can be used to prepare the lithium or lithium alloy film of the present technology is preferably electrically conductive. It is understood that the presence of the metal element is desirable not to inhibit the electrical conductivity of the lithium or lithium alloy film. For example, aluminum is a metal element that can be used in the lithium or lithium alloy film. In some examples, aluminum is present in the film in an amount ranging from about 3000 ppm to about 10000 ppm, or from about 3000 ppm to about 9000 ppm, or from about 3000 ppm to about 8000 ppm, or from about 3000 ppm to about 7000 ppm, or from about 3000 ppm to about 6000 ppm, or from about 300 ppm to about 5000 ppm. In some embodiments, aluminum is present in the film in an amount of 3000 ppm or more.

[0066] In some embodiments, the lithium or lithium alloy films of the present technology have a hardness, as measured by Shore A scale, ranging from about 50 to about 85, or between about 60 and about 80, or between about 60 and about 75, or between about 50 and about 70, or between about 60 and about 75, or between about 65 and about 75, or between about 66 and 70, or between about 66 and 69. In some examples, the hardness is at least 65. In some other examples, the hardness is at least about 66. In some examples, the hardness is uniform throughout the lithium or lithium alloy film.

[0067] The lithium films obtained by the techniques defined herein have a width (corresponding to the distance from one end of the film to the other) ranging between about 140 mm and about 200 mm, or between about 150 mm and about 200 mm, or between about 160 mm and about 180 mm, or between about 160 mm and about 175 mm, or between about 160 mm and about 170 mm, or between about 160 mm and about 165 mm, and a thickness ranging between about 20 microns and about 100 microns, or between about 20 microns and about 90 microns, or between about 20 microns and about 75 microns, or between about 20 microns and about 50 microns, or between about 20 microns and about 30 microns. The thickness of the lithium or lithium alloy film is uniform across the entire width of the film. A uniform thickness across the entire width of the film encompasses a thickness variation of about ±2 microns.

[0068] In some embodiments, the lithium or lithium alloy films obtained by the techniques defined herein have a melting point of about 1×10 -4 ~Approx. 7×10 -4 In some instances, the membrane has a thickness / width (t / w) ratio that is between 0.01 and 0.05. ...

[0069] In particular, the present technology allows the lithium or lithium alloy film to maintain its width, thickness, and hardness over extended film lengths, for example, the lithium or lithium alloy film of the present technology maintains its width, thickness, and hardness over at least about 15,000 meters, at least about 10,000 meters, at least about 9,000 meters, at least about 8,000 meters, at least about 7,000 meters, at least about 6,000 meters, at least about 5,000 meters, at least about 4,000 meters, at least about 3,000 meters, at least about 2,000 meters, or at least about 1,000 meters. EXAMPLES

[0070] The following examples are provided to illustrate the practice of various embodiments of the present technology. They are not intended to limit or define the full scope of the present technology. It should be understood that the present technology is not limited to the specific embodiments described and illustrated herein, but includes all modifications and variations that fall within the scope of the present disclosure defined in the accompanying embodiments.

[0071] [Example 1 - Production of Laminated Lithium Alloy Film (3000 ppm)] A laminated lithium film was prepared using a rolling mill including working rollers as defined herein. The resulting lithium film had a width of 170 mm, a thickness of 60 microns, and an aluminum content of 3000 ppm. The hardness of the film was evaluated using a Shore Durometer (PTC Model 320-A scale). The results are shown in Table 1.

[0072] [Table 1]

[0073] [Example 2 - Production of Laminated Lithium Alloy Film (5000 ppm)] A laminated lithium film was prepared using a rolling mill including working rollers as defined herein. The resulting lithium film had a width of 170 mm, a thickness of 60 microns, and an aluminum content of 5000 ppm. The hardness of the film was evaluated using a Shore Durometer (PTC Model 320-A scale). The results are shown in Table 2.

[0074] [Table 2]

[0075] [Example 3 - Evaluation of tensile strength of laminated lithium alloy film (3000 ppm)] A laminated lithium film was prepared using a rolling mill including working rollers as defined herein. The lithium film had a width of 170 mm, a thickness of 60 microns, and an aluminum content of 3000 ppm. The tensile strength of the lithium film was evaluated using a test metric M500 25 kN. The results are shown in Table 3.

[0076] [Table 3]

[0077] [Example 4 - Evaluation of tensile strength of laminated lithium alloy film (5000 ppm)] A laminated lithium film was prepared using a rolling mill including working rollers as defined herein. The lithium film had a width of 170 mm, a thickness of 60 microns, and an aluminum content of 5000 ppm. The tensile strength of the lithium film was evaluated using a test metric M500 25 kN. The results are shown in Table 4.

[0078] [Table 4]

[0079] Modifications and improvements to the above-described embodiments of the technology will be apparent to those skilled in the art. The foregoing description is intended to be illustrative rather than limiting. Accordingly, the scope of the technology is intended to be limited only by the appended claims.

[0080] [1] A laminated lithium or lithium alloy film obtained by a rolling mill, the rolling mill comprising: Frame; a first work roller rotatably mounted on said frame; a second work roller rotatably mounted to the frame, the first and second work rollers being positioned to receive a sheet therebetween; at least two first actuators operatively connected to opposite ends of the first working roller for bending the first working roller; and at least two second actuators operatively connected to opposite ends of the second work roller for bending the second work roller; Including, Each of the first and second work rollers is a cylindrical central portion defining a central axis, the cylindrical central portion having an outer surface defining a lamination surface; a first frustoconical portion extending from a first end of the central portion; and a second frusto-conical portion extending from a second end of the central portion; Including, an angle between an outer surface of the central portion and an outer surface of each of the first and second frusto-conical portions is less than 0.05 degrees when the central axis is straight; a width of the central portion is greater than a width of each of the first and second frustoconical portions; A laminated lithium or lithium alloy film obtained by the rolling machine, wherein the width of the central portion is smaller than the sum of the widths of the first and second portions. [2] A laminated lithium or lithium alloy film obtained by a rolling machine including a working roller, the working roller being: a cylindrical central portion defining a central axis, the cylindrical central portion having an outer surface defining a lamination surface; a first frustoconical portion extending from a first end of the central portion; and a second frusto-conical portion extending from a second end of the central portion; Including, an angle between an outer surface of the central portion and an outer surface of each of the first and second frusto-conical portions is less than 0.05 degrees when the central axis is straight; a width of the central portion is greater than a width of each of the first and second frustoconical portions; A laminated lithium or lithium alloy film obtained by a rolling machine including working rollers, the width of the central portion being less than the sum of the widths of the first and second portions. [3] A lithium or lithium alloy film comprising a metal element, the metal element being present in the lithium or lithium alloy film in an amount of at least 3000 ppm; the lithium or lithium alloy film having a metal content of at least about 1×10 -4 ~Approx. 7×10 -4 A lithium or lithium alloy film having a thickness to width ratio between [4] The lithium or lithium alloy film according to [3], wherein the lithium or lithium alloy film is laminated. [5] The lithium or lithium alloy film according to [3] or [4], wherein the metal element is aluminum. [6] The lithium or lithium alloy film according to [5], wherein the aluminum is present in the lithium or lithium alloy film in an amount of between about 3,000 ppm and about 10,000 ppm, about 3,000 ppm and about 9,000 ppm, about 3,000 ppm and about 8,000 ppm, about 3,000 ppm and about 7,000 ppm, about 3,000 ppm and about 6,000 ppm, or about 3,000 ppm and about 5,000 ppm. [7] The lithium or lithium alloy film according to any one of [3] to [6], wherein the thickness is between about 20 microns and about 100 microns. [8] The lithium or lithium alloy film according to any one of [3] to [6], wherein the width is between about 140 mm and about 200 mm. [9] The lithium or lithium alloy film according to any one of [3] to [8], having a hardness of between about 50 and about 75 on the Shore A scale.

[10] The lithium or lithium alloy film according to any one of [3] to [8], having a hardness of between about 66 and about 69 on the Shore A scale.

[11] The lithium or lithium alloy film according to any one of [3] to [8], having a hardness of at least 66 on the Shore A scale.

[12] The lithium or lithium alloy film of any one of [3] to

[11] , wherein the lithium or lithium alloy film has a length and the ratio of thickness to width is uniform over the entire length.

[13] The lithium or lithium alloy film of

[12] , wherein the length is at least 3000 meters.

[14] The lithium or lithium alloy film of

[12] , wherein the length is at least 5000 meters.

[15] A laminated lithium or lithium alloy film comprising at least about 3000 ppm aluminum, the laminated lithium or lithium alloy film having a thickness, a width and a length, the thickness to width ratio being about 1×10 -4 ~Approx. 7×10 -4 and is uniform throughout the entire length of the lithium or lithium alloy film. [Explanation of symbols]

[0081] 10 Rolling machine, lamination equipment 12 Lithium or lithium alloy thin film 14 Lithium or lithium alloy sheet 16 Mainframe 18a, 18b Working rollers 20a, 20b Backup rollers 22, 200 Lubricant distribution unit for lamination 24, 92 rolls 26 Supply roller 28, 34 Free roller 30 Straightener 32 Dense Roller 36 Optical Fireproofing System 38 Drive winding roller 41, 47 Encoder roller 43, 45, 94 Tension roller 50, 52 Support frame 54, 56 Support member 58, 59, 62, 63 Ends of support members 60, 61, 64, 65, 66 Hydraulic Linear Actuator 84, 85 Free Zone 90 Insulating Film 100 central part 102 Outer surface of central part 104 Center axis 106 Cone-shaped part 108 Shoulder 110 Outer surface of the truncated cone 116, 118 Support shaft 150 nozzles 152 Rail 154 Intake connector 156 Nozzle body 158 Nozzle Head 160 Nut 202 Distribution unit body 206 Opening 208 Horizontal Wall 214 Back wall 216 Exit 220 front end 222 Ledge 224 Recess 226 Leading Edge 228 Angled Section 230 Corner 232 Generally horizontal area 234 Gutter 236 Pump 238 Lubricant Reservoir

Claims

1. A lithium or lithium alloy film comprising a metallic element, said metallic element being aluminum, present throughout said lithium or lithium alloy film in an amount between 3000 ppm and 10000 ppm to enhance mechanical strength throughout the width, thickness and length of said lithium or lithium alloy film; said lithium or lithium alloy film having a molecular weight of about 1×10 －４ ~Approx. 7×10 －４ and the lithium or lithium alloy film comprising said metallic element is suitable for use as part of or as an anode.

2. 10. The lithium or lithium alloy film of claim 1, wherein the lithium or lithium alloy film is laminated.

3. The lithium or lithium alloy film of claim 1 or 2, wherein the thickness is between about 20 microns and about 100 microns.

4. 4. The lithium or lithium alloy film of claim 1, wherein the width is between about 140 mm and about 200 mm.

5. 5. The lithium or lithium alloy film of claim 1 having a hardness of between about 50 and about 75 on the Shore A scale.

6. 5. The lithium or lithium alloy film of claim 1 having a hardness of between about 66 and about 69 on the Shore A scale.

7. 5. The lithium or lithium alloy film of claim 1 having a hardness of at least 66 on the Shore A scale.

8. 8. The lithium or lithium alloy film of claim 1, wherein the lithium or lithium alloy film has a length and the thickness to width ratio is uniform along the length.

9. 9. The lithium or lithium alloy film of claim 8, wherein said length is at least 3000 meters.

10. 9. The lithium or lithium alloy film of claim 8, wherein said length is at least 5000 meters.

Images