Temperature-controllable calender roller for producing electrode tracks using a dry electrode process

Abstract

The present invention relates to a temperature-controllable calender roller for manufacturing electrode tracks using a dry electrode method, the temperature-controllable calender roller having a roller body and two roller journals extending outward from an end face of the roller body, a fluid channel arrangement for temperature control of the roller body, the fluid channel arrangement having a central bore extending axially at least partially through the roller body and through at least one of the roller journals, a plurality of temperature control channels distributed over the circumference of the roller body, extending below the roller body surface parallel to the roller body and fluidically coupled to the central bore, inlet and outlet lines for thermal fluid, the inlet and outlet lines being connected to the fluid channel arrangement, the inlet line having a supply pipe extending at least partially into the central bore for introducing the thermal fluid into the fluid channel arrangement, the outlet line being fluidically coupled to an outer gap of the fluid channel arrangement formed between the outside of the supply pipe and the inner diameter of the central bore.

Description

[Technical field]

[0001] The present invention relates to a temperature-controllable calender roller for manufacturing electrode tracks using a dry electrode process, comprising a roller body and two roller journals extending from an end face of the roller body, wherein a fluid channel arrangement is provided inside the calender roller. [Background technology]

[0002] A hollow roller with a temperature control device is known from document DE 33 21 122 A1. It has a number of passages extending parallel to the roller surface for conducting a temperature control fluid and a central bore connected to the passages, by which the passages are supplied with the fluid.

[0003] The manufacture of electrode tracks using dry electrode processes requires process temperatures in excess of 100°C. Therefore, the calender rollers used in the manufacture of the electrode tracks need to be heated. However, one problem with heating the rollers is that in some circumstances the roller surface has a temperature gradient along its axial direction, which causes, for example, the temperature of the central region of the roller to be higher than that of the outer regions at the edges. This causes crowning, i.e. a thickening of the cross section that deviates from a cylindrical shape, as the more heated roller material expands more in the center than the less heated material in the edge regions. However, there is a requirement for the electrode track of a battery cell to have the most uniform possible thickness across its width. Therefore, crowning occurring when the roller is heated needs to be avoided. Summary of the Invention

[0004] It is therefore an object of the present invention to improve a temperature controllable calender roller for producing electrode tracks using a dry electrode process in such a way as to have a uniform temperature profile on the roller surface.

[0005] The invention is achieved by a temperature-controllable calender roller having the features of claim 1. Further advantageous embodiments of the invention are described in the dependent claims.

[0006] It is therefore provided that the calender roller has a fluid channel arrangement for temperature control of the roller body, the fluid channel arrangement having a central bore extending axially at least partially through the roller body and through at least one of the roller journals, and a plurality of temperature control channels distributed over the circumference of the roller body and extending below and parallel to the roller body surface, the plurality of temperature control channels being fluidically coupled to the central bore. Furthermore, the calender roller has inlet and outlet lines for a thermal fluid, the inlet and outlet lines being connected to the fluid channel arrangement, the inlet line having a supply pipe extending at least partially into the central bore for introducing the thermal fluid into the fluid channel arrangement, the outlet line being fluidically coupled to an outlet gap of the fluid channel arrangement formed between the outside of the supply pipe and the inner diameter of the central bore. The fluid channel arrangement can be used to heat the roller to a process temperature provided by a thermal fluid, such as oil, for example. Alternatively, it can be provided that, for example, if a calendar roller needs to be removed for maintenance reasons, a cooling medium, which may be the same as the thermal fluid used for heating, can be directed through the fluid channel arrangement to reduce the cooling time of the roller before it is ready for removal.

[0007] It can be defined that the inlet line and the outlet line open into the same roller journal of the calender roller, the temperature control channel is fluidly connected to the supply pipe via a plurality of inlet channels and fluidly connected to the outlet gap via a plurality of outlet channels, the inlet channels opening into the central bore on the side facing opposite the inlet lines and the outlet channels opening into the outlet gap.

[0008] It can further be provided that the supply pipe extends axially into the central bore beyond the opening of the mouth of the inlet channel. The supply pipe can for example extend axially to or into the opposite roller journal. This allows a better circulation of the thermal fluid in the roller journal in relation to a shorter supply pipe. Furthermore, in the region between the outlet of the supply pipe and the mouth region of the inlet channel, an inlet gap can be formed between the outside of the supply pipe and the inlet of the central bore, through which the thermal fluid can flow towards the mouth region of the inlet channel after leaving the outlet of the supply pipe.

[0009] It can further be defined that the central bore is a through hole extending through both the roller journal and the roller body, and that the supply pipe extends into the central bore up to the area of ​​the roller journal opposite the inlet line. Between the outlet of the supply pipe and the end of the central bore, a cover can be closed, providing a space through which the thermal fluid can flow. Thus, heating of the entire roller including the roller journal can be effectively achieved, and the temperature gradient between the roller body and the roller journal is avoided, resulting in a more uniform temperature distribution along the roller surface.

[0010] It is envisaged that the mouth region of the inlet channel is sealed from the mouth region of the outlet channel by at least one sealing bushing disposed between said regions on the outside of the supply pipe. It is further envisaged that two spaced apart sealing bushings are disposed on the outside of the supply pipe between the mouth region of the inlet channel and the mouth region of the outlet channel, whereby no thermal fluid is present in the enclosed area between the sealing bushings between the outside of the supply pipe and the inner diameter of the central bore.

[0011] It is conceivable that an odd number of temperature control channels, spaced parallel to one another in the direction of rotation of the roller, are arranged between each inlet channel and its assigned outlet channel, through which the thermal fluid is guided in an axial meandering manner according to the number of temperature control channels, thereby maximizing the number of temperature control channels extending under the roller surface, since the maximum number of inlet and outlet channels leading to the central bore is limited by the diameter ratio of the central bore to the inlet and outlet channels.

[0012] It can be provided that the temperature control channels are each designed as a through hole guided through the roller body, and adjacent temperature control channels are connected to each other by essentially tangentially extending, axially sealed grooves introduced into the end faces.

[0013] It can further be provided that the roller body has an axial annular groove in the region of the temperature control channel on both end faces of the roller body, into which a cover cap having a groove and a bore is inserted and axially sealed using a sealing element. The sealing element can essentially completely cover the end faces of the roller body. The sealing element can also have a low thermal conductivity of less than 3 W / (m·K). This makes it possible to avoid heat radiation or air convection along the end faces, so that the thermal gradient along the distance traveled through the roller of the fluid flowing through the roller is as small as possible. Each hole can be aligned and adjacent to a temperature control channel connected to the inlet or outlet channel, which increases the contact area between the cover cap and the thermal fluid.

[0014] It may further be provided that the central bore is closed at an end opposite the inlet line with a cover.

[0015] It is contemplated that the inlet channel extends axially from the inlet side and radially away from the central bore in a first diagonal direction, and the outlet channel extends axially towards the inlet side and radially away from the central bore in a second diagonal direction.

[0016] Furthermore, it is conceivable that the fluid channel arrangement comprises a thermal insulating element, at least in the region of the roller journal which contains said arrangement, in order to thermally shield the fluid channel arrangement from the roller journal.

[0017] It is also conceivable that the insulating element consists of a material having a thermal conductivity of less than 0.3 W / (m·K), such as PTFE.

[0018] It can further be provided that the fluid channel arrangement extends at least partially through both roller journals, and that the fluid channel arrangement has insulating elements in the region of both roller journals for thermally shielding the fluid channel arrangement from each roller journal.

[0019] It may be provided that at least one insulating element in the form of an insulating sleeve lining the central bore is inserted within the central bore.

[0020] The invention further relates to a process for manufacturing electrode tracks, said process comprising the steps of: providing a powder electrode precursor material and at least one calender roller, the calender roller having a fluid channel configuration for temperature control of the calender roller; heating the calender rollers by directing a fluid through the fluid channel arrangement; and contacting the calender rollers with the powdered electrode precursor material.

[0021] It may be specified that the fluid is oil. It may be envisaged that the fluid is maintained at a temperature between 30°C and 200°C. It may further be envisaged that the fluid is maintained at a temperature between 60°C and 150°C. It may further be specified that the fluid is maintained at a temperature between 90°C and 120°C.

[0022] It may further be provided that a cooling medium is directed through the fluid channel arrangement to cool the calender rollers, the temperature of the cooling medium being maintained at a lower temperature than the temperature of the calender rollers.

[0023] The invention further relates to a dry electrode manufactured by a process according to any one of claims 17 to 22. The dry electrode may have a thickness tolerance of less than 1 μm.

[0024] The present invention further relates to a process for manufacturing a calender roller, the process comprising manufacturing one or more calender roller parts and connecting the one or more calender roller parts, the one or more calender roller parts comprising at least one supply pipe, at least one temperature control channel and at least one outlet line, the calender roller having a first end and a second end, the at least one supply pipe extending from the first end to the second end.

[0025] It may further be provided that one or more of the calender roller parts are manufactured by CNC machining, forging, investment casting, injection molding, die casting, additive manufacturing, or combinations thereof.

[0026] It may further be provided that one or more of the calender roller components are connected by metal gas welding, arc welding, tungsten inert gas welding, flux core welding, soldering, blending, adhesive bonding, or combinations thereof.

[0027] Further, manufacturing of at least one insulating sleeve and connection of the insulating sleeve to one or more calender roller parts may be provided, the at least one insulating sleeve may be manufactured by transfer molding, injection molding, melt molding, compression molding, vacuum forming, pultrusion, or a combination thereof, and the at least one insulating sleeve may be connected to one or more calender roller parts by gluing, mechanical fastening, or a combination thereof.

[0028] Further, manufacturing of at least one insulation layer and connection of the insulation layer to one or more calender roller parts may be provided, the at least one insulation layer may be manufactured by transfer molding, injection molding, melt molding, compression molding, vacuum forming, pultrusion, or a combination thereof, and the at least one insulation layer may be connected to one or more calender roller parts by gluing, mechanical fastening, or a combination thereof.

[0029] It can further be specified that the calender roller has a surface, further comprising treating the surface of the calender roller, wherein the surface of the calender roller is treated using a microetching process, a laser engraving process, a super-abrasive process, or a combination thereof.

[0030] Exemplary embodiments of the invention will now be described with reference to the following drawings. [Brief description of the drawings]

[0031] [Figure 1] 1 shows a cross-sectional view of an embodiment of a temperature-controllable calender roller according to the present invention; [Diagram 2] FIG. 2 shows a perspective view of an embodiment of a temperature-controllable calender roller according to the present invention. [Diagram 3] 1 shows a cross-sectional view of an embodiment of a temperature-controllable calender roller according to the present invention having parallel running temperature control channels. [Figure 4] 1 shows a cross-sectional view of the intersection between a temperature control channel and an inlet channel. [Diagram 5] 13 shows a detailed view of connecting grooves of a temperature control channel in half cross section. [Figure 6] 1 is a perspective view of a roller journal and a cover cap attached to an end face of a roller body. FIG. [Figure 7] 1 shows a flow chart of a process for manufacturing a dry electrode. [Figure 8] FIG. 2 shows a diagram with measurement results of a thermal crowning test on a standard roller. [Figure 9]1 shows a diagram of thermal crowning test measurements for rollers with modified end caps. [Figure 10] 1 shows a diagram of the measurement results of a thermal crowning test of a roller with an extended supply pipe. [Figure 11] FIG. 2 shows a diagram with measurement results of a thermal crowning test on a calender roller. [Figure 12] FIG. 2 shows a diagram with measurement results of a thermal crowning test on a calender roller. [Figure 13] FIG. 2 shows a diagram with measurement results of a thermal crowning test on a calender roller.

[0032] The temperature-controllable calender roller 1 shown in Fig. 1 has a roller body 2 with two roller journals 3 protruding from the roller body 2 in opposite directions. A fluid channel arrangement 4 is arranged inside the roller 1, which comprises, on the one hand, a central bore 5 extending through the roller 1 in the axial direction X and a number of temperature control channels 6 distributed over the circumference of the roller and arranged below and parallel to the roller surface. The central bore 5 is fluidly connected to the temperature control channels 6 via a number of inlet channels 11 extending diagonally and a number of outlet channels 12 extending diagonally in the opposite direction. The inlet channels 11 open into the central bore 5 at a first mouth area 13, and the outlet channels 12 open into a second mouth area 14. A supply pipe 9 is inserted into the central bore 5 and is fluidly connected to an inlet line 7 through which the thermal fluid is supplied to the roller 1. The length of the supply pipe 9 is dimensioned such that it projects beyond both mouth areas 13, 14, and the outlet 24 of the supply pipe 9 projects beyond the first mouth area 13 of the inlet channel 11. In the first and second mouth areas 13, 14 the supply pipe 9 has a diameter difference with respect to the central bore 5, forming a gap between the outer diameter of the supply pipe 9 and the inner diameter of the central bore 5. That is to say, an inlet gap 30 between the outlet 24 and the first mouth area 13, and an outlet gap 10 between the second mouth area 14 to the axial end of the roller journal 3 on the right side of the image is formed. Between the first mouth area 13 and the second mouth area 14 the supply pipe 9 is sealed against the central bore 5 by two sealing bushings 15, which prevent the thermal fluid from flowing back through the central bore 5 from the first mouth area 13 and the second mouth area 14. The sealing bushings 15 form an enclosed section 16 between them. Thus, the thermal fluid first enters the supply pipe 9 through the inlet line 7 and then flows along the supply pipe 9 once laterally through the central bore 5 to the outlet 24 of the supply pipe 9. After the outlet 24, the thermal fluid first enters the section of the central bore 5 that extends into the left roller journal 3, which section is closed at its end using a cover 22. This section also has an insulating sleeve 23 made of Teflon, which lines the central bore 5 and thermally seals it against the roller journal 3.When this space is filled, the thermal fluid flows in the opposite direction into the inlet gap 30 between the supply pipe 9 and the central bore 5, and from there into the individual inlet channels 11. The thermal fluid flows through the inlet channels 11 which open into the temperature control channels 6, and thus parallel underneath the roller surface, which is heated. After flowing through the temperature control channels 6, the thermal fluid flows into the outlet channels 12, through these into the discharge gap 10, through which the thermal fluid is supplied to the outlet line 8, which is located on the same roller journal 3 as the inlet line 7.

[0033] FIG. 2 shows a perspective view of the temperature-controllable calender roller 1. In contrast to the configuration shown in FIG. 1, it does not have an insulating sleeve 23, so that both areas of the central bore 5 located inside the roller journals 3 are not thermally sealed against the roller journals 3. Also visible are the cover caps 20, each of which is arranged in an axial annular groove 18 and introduced into the roller body 2 at its end faces on both sides. FIG. 2 also shows a detailed view of the supply pipe 9 as installed on the roller 1 and in a separate representation next to the roller 1. On the inlet side, i.e. opposite the outlet 24, the supply pipe 9 has a connection piece for coupling to the inlet line 7. On the outside of the supply pipe 9, two sealing bushings 15 are arranged at a distance from each other and seal the supply pipe 9 against the central bore. The sealing bushings 15 are also used as sliding bushings to facilitate the installation of the supply pipe 9 in the central bore 5.

[0034] FIG. 3 shows a detailed view of the temperature control channels 6 extending below the roller surface, illustrating the path of the thermal fluid through the temperature control channels 6. The thermal fluid enters the axially extending first temperature control channel 6.1 through the inlet 26, which is fluidly connected to its associated inlet channel 11 (not shown). The thermal fluid then enters the second temperature control channel 6.2 through a radially extending groove 17 (not shown) in the cover cap 20 opposite the inlet 26. The second temperature control channel 6.2 extends parallel to the first temperature control channel 6.1 and is spaced apart from each other. In the second temperature control channel 6.2, the thermal fluid now flows in the opposite direction, back towards the side of the inlet 26. At the opposite end, a further cover cap 20 is attached, which has a corresponding radially extending groove 17 (not shown) connecting the second temperature control channel 6.2 to a third temperature control channel 6.3, which is also arranged parallel to the first and second temperature control channels 6.1, 6.2 and spaced apart from each other in the circumferential direction of the roller 1. Through the third temperature control channel 6.3, the thermal fluid again flows away from the inlet side to an outlet 25 located at the end of the third temperature control channel 6.3, from where it flows into an outlet channel 12 (not shown) assigned to the outlet 25.

[0035] FIG. 4 shows a detailed view of the mouth area between the temperature control channel 6 and the inlet channel 11 of the fluid channel arrangement 4. The temperature control channels 6 are each designed as a through hole extending through the roller body 2. In the area where the temperature control channels 6 open into the end face of the roller body 2, the roller body has an axial annular groove 18. An annular cover cap 20 is inserted into the annular groove 18, which is screwed to each end face of the roller body 2 and has a number of blind holes 19 or grooves 17. The blind holes 19 respectively represent an end section of each temperature control channel 6, which protrudes into the cover cap 20 and abuts on each blind hole 19. With reference to FIG. 3, the cover cap 20 has such blind holes 19 on the inlet side of the first temperature control channel 6.1 and on the outlet side of the third temperature control channel 6.3. The blind holes 19 increase the contact area between the thermal fluid and the cover cap 20, which allows the cap to more effectively release heat to the roller body 2. This means that whenever an inlet channel 11 or an outlet channel 12 flows into a temperature control channel 6, a blind hole 19 is assigned to the temperature control channel 6. A flat seal 27 for axial sealing is arranged between the cover cap 20 and the bottom of the axial annular groove 18. For radial sealing, a first O-ring 28.1 is inserted into the outer radial groove of the cover cap 20 and a second O-ring 28.2 is inserted into the inner radial groove of the cover cap 20. For additional sealing of the cover cap 20 from external influences, a flat sealing element 21 is arranged on the outer end face of the cover cap 20. The sealing element 21 covers as large a surface area as possible of the end face of the roller body 2 in order to minimize heat losses at the end face. The sealing element 21 consists of a heat-insulating material with low thermal conductivity.

[0036] FIG. 5 again shows the contact area between the temperature control channels 6 and the cover cap 20 seen in the circumferential direction of the roller 1. Although only partially shown, the temperature control channels 6 are distributed at regular intervals over the circumference of the roller and each borders at its end face either one of the blind holes 19 or one of the grooves 17. Each blind hole 19 borders a temperature control channel 6 and each of the grooves 17 borders two temperature control channels 6, the grooves 17 being used to divert the thermal fluid from one temperature control channel bordering the groove 17 to the other temperature control channel bordering the groove 17. Each temperature control channel configuration, consisting of three interrelated temperature control channels 6.1, 6.2 and 6.3 sharing a common inlet channel 11 and a common outlet channel 12, is therefore assigned a blind hole 19 and an adjacent groove 17 in the cover cap 20 on both sides. The cover cap 20 is inserted into an axial annular groove 18 introduced into the end face of the roller body and is screwed onto the roller body 2 via a bore 29 introduced into the cover cap 20 .

[0037] 6 shows a perspective view of the roller journal 3 with the roller body adjacent and a cover cap 20 inserted therein, the cap being shown in half section so as to show the rear grooves 17 and the bores 19. It can be seen that the bores 19 and grooves 17 are provided alternately and are regularly spaced from one another.

[0038] FIG. 7 shows a flow chart for manufacturing an electrode track. The method includes providing (701) a dry electrode precursor material and a calender roller including at least one supply pipe, at least one temperature-controlled channel, and at least one outlet line, heating (702) the calender roller by directing a fluid through the at least one temperature-controlled channel, and contacting (703) the calender roller with the dry electrode precursor material. In some embodiments, the calender roller is heated (702) by directing a fluid through the at least one temperature-controlled channel, the fluid being maintained at a temperature higher than the temperature of the environment immediately surrounding the calender roller. The fluid may be any fluid suitable for heating the calender roller and known to those skilled in the art.

[0039] In some embodiments, the fluid is oil. In some embodiments, the fluid is maintained at a temperature value or temperature range of about 30°C, about 35°C, about 40°C, about 45°C, about 50°C, about 55°C, about 60°C, about 65°C, about 70°C, about 75°C, about 80°C, about 85°C, about 90°C, about 95°C, about 100°C, about 105°C, about 110°C, about 115°C, about 120°C, about 125°C, about 130°C, about 135°C, about 140°C, about 145°C, about 150°C, about 160°C, about 170°C, about 180°C, about 190°C, about 200°C, or between two of these values. In some embodiments, the method further comprises cooling the calender rollers by passing a cooling fluid through at least one temperature control channel, the cooling fluid being maintained at a temperature lower than the temperature of the calender rollers. In some embodiments, the cooling gas is air.

[0040] A process for manufacturing a calender roller comprising at least one supply pipe, at least one temperature control channel, and at least one outlet line can be summarized. The process includes manufacturing one or more calender roller parts, the one or more calender roller parts including at least one supply pipe, at least one temperature control channel, and at least one outlet line, and connecting the one or more calender roller parts. In some embodiments, the calender roller has a first end and a second end, and at least one supply pipe extends from the first end to the second end. The calender roller can be manufactured using any manufacturing process known in the art. In some embodiments, the calender roller is manufactured by CNC machining, forging, investment casting, injection molding, die casting, additive manufacturing, or a combination thereof.

[0041] In some embodiments, the calender roller part or parts can be connected by any method deemed suitable by one skilled in the art of connecting metal parts. For example, the calender roller part or parts can be connected by gas metal arc welding, arc welding, tungsten inert gas welding, flux core welding, brazing, mixing, gluing, or a combination thereof.

[0042] In some embodiments, the process further includes manufacturing at least one insulating sleeve. The at least one insulating sleeve can be manufactured by any manufacturing process known to those skilled in the art. In some embodiments, the at least one insulating sleeve is manufactured by transfer molding, injection molding, melt molding, compression molding, vacuum forming, pultrusion, or a combination thereof. In some embodiments, the at least one insulating sleeve is connected to one or more calender roller parts. The at least one insulating sleeve may be connected to one or more calender roller parts by any process known to those skilled in the art. For example, the at least one insulating sleeve can be connected to one or more calender roller parts by adhesive, mechanical fastening, or a combination thereof.

[0043] In some embodiments, the process further includes manufacturing at least one insulation layer. The at least one insulation layer can be manufactured by any manufacturing process known to those skilled in the art. In some embodiments, the at least one insulation layer is manufactured by transfer molding, injection molding, melt molding, compression molding, vacuum forming, pultrusion, or a combination thereof. In some embodiments, the at least one insulation layer is connected to one or more calender roller parts. The at least one insulation layer may be connected to one or more calender roller parts by any process known to those skilled in the art. For example, the at least one insulation layer can be connected to one or more calender roller parts by adhesive, mechanical fastening, or a combination thereof.

[0044] In some embodiments, the method further comprises treating the surface of the calender roller after the calender roller is manufactured. In some embodiments, the surface of the calender roller is treated using a microetching process, a laser engraving process, a super polishing process, or a combination thereof. Metal surfaces often have scratches and defects that can adversely affect the efficiency of the electrodes manufactured by the calender roller. By combining microetching and laser engraving, material is removed from the metal surface and the defects are removed.

[0045] The superabrasive treatment reduces the surface roughness of the roller by eliminating surface defects. In some embodiments, the entire surface of the roller is treated using superabrasive. In some embodiments, the superabrasive treatment is applied to a portion of the roller surface. In some embodiments, the average surface roughness of the roller is less than about 0.1 μm, less than about 0.09 μm, less than about 0.08 μm, less than about 0.07 μm, less than about 0.06 μm, less than about 0.05 μm, less than about 0.04 μm, less than about 0.03 μm, less than about 0.02 μm, or less than about 0.01 μm.

[0046] Working Example Example 1: Manufacture of calender rollers The calender rollers were prepared by cleaning the surface of the rollers to remove any contaminants, and the heating system and hydraulic unit were turned on. Then, a first set of nickel foam strips was placed on the surface of the calender rollers. Each nickel foam strip was 10 mm wide and 300 mm long. The strips were applied along the entire length of the roller with a distance of 50 mm between each individual strip. In this way, 31 strips were distributed over the entire length of the roller, each corresponding to a position on the roller. A second set of nickel foam strips was similarly applied to the roller on the opposite side of the first set of nickel foam strips. Then, each roller was placed next to the calender roller and rotated until each nickel foam strip passed through the nip. The rollers rotated at a speed of 2 m / min, the tensile force was 150 kN, and the distance between the rollers was 350 μm. Then, each nickel foam strip was removed from the roller and the thickness of the strip was measured. The tests were carried out using three variants, including a standard roller, a roller with modified end caps, and a roller with an extended feed pipe.

[0047] Example 2: Standard calender roller Testing was performed with two standard rollers according to the parameters described in Example 1. Testing was performed with the rollers heated to 20° C., 90° C., 120° C., and 150° C. The results for each nickel foam strip and the measurements from each roller were averaged and are shown in FIG.

[0048] Example 3: Calender Roller with Modified End Caps Testing was performed on two rollers according to the parameters described in Example 1. The first roller tested was a standard roller. The second roller tested had modified end caps. On the second roller, the caps were crushed and the flat seals were removed. During testing, the rollers were heated to 20° C., 90° C., 120° C., and 150° C. The results for each nickel foam strip and the measurements from each roller were averaged and are shown in FIG. 9.

[0049] Example 4: Calender roller with extended supply pipe Testing was performed on two rollers according to the parameters described in Example 1. The first roller had an elongated feed pipe and all other features corresponded to the standard roller. The second roller also included an elongated feed pipe and the flat seal was removed from the roller. Testing was performed by heating the rollers to 20°C, 90°C, 120°C, and 150°C. The results for each nickel foam strip and the measurements from each roller were averaged and are shown in Figure 10.

[0050] Example 5: Comparison of different calender rollers The thermal crowning measurements for each of the three roller variants were averaged and compared at the different test temperatures. It is noted that at 90°C, only the roller with the extended feed pipe resulted in an average thickness variation within the acceptable 1 μm tolerance across the entire working zone between positions 4 and 28. The standard roller had an average thickness variation within the acceptable 1 μm tolerance between positions 8 and 26, and the roller with the modified end cap had an average thickness variation within the acceptable 1 μm tolerance between positions 5 and 27. The results of the tests at 90°C are shown in Figure 11. At 120°C, the roller with the extended feed pipe had an average thickness variation within the acceptable 1 μm tolerance between positions 5 and 27. For the standard roller, the average thickness variation between positions 8 and 25 was within the acceptable tolerance of 1 μm, and for the roller with the modified end cap, the average thickness variation between positions 7 and 27 was within the acceptable tolerance of 1 μm. The results of the test at 120 °C are shown in Figure 12. At 150 °C, the roller with the extended feed pipe had an average thickness deviation within the acceptable tolerance of 1 μm between positions 5 and 26. For the standard roller, the average thickness variation between positions 7 and 25 was within the acceptable tolerance of 1 μm, and for the roller with the modified end caps, the average thickness variation between positions 7 and 27 was within the acceptable tolerance of 1 μm. The results of the test at 150 °C are shown in Figure 13. The thickness tolerance of the nickel foam strip was increased as a result of the reduction in thermal crowning due to the extension of the feed pipe. This increases the potential working area of ​​the calender roller in the production of the electrodes, and the ratio of the potential working area of ​​the calender roller to the total length of the calender roller is increased. The increase in the potential working area over the entire working zone eliminates the need to trim the edges of the produced electrodes, which would otherwise have poor dimensional accuracy. The ratio between the potential working area and the roller length was calculated by dividing the acceptable tolerance value length of the roller by the total length of the roller of 1,600 mm. The difference in the ratio between the working area of ​​the calender roller and the total length of the calender roller for each roller at each temperature tested is shown in Table 1 below. [Table 1]

[0051] The features of the invention disclosed in the above description, in the drawings and in the claims may be essential to the implementation of the invention both individually and in any combination.

[0052] Explanation of symbols 1.Temperature-controllable calender roller 2. Roller body 3. Laura Journal 4. Fluidic Channel Construction 5.Central bore 6. Temperature Control Channel 6.1. First temperature control channel 6.2. Second Temperature Control Channel 6.3.Third Temperature Control Channel 7. Entrance Line 8. Exit Line 9. Supply pipe 10. Exit Gap 11. Entrance channel 12. Exit Channel 13. Inlet channel mouth area 14. Mouth area of ​​the outlet channel 15. Sealing bushing 16. Enclosed Section 17. Groove 18. Axial annular groove 19.Blind Hole 20.Cover cap 21. Sealing elements 22. Cover 23. Insulating sleeve 24.Exit 25.Entrance 26.Exit 27. Flat Seal 28.1.O-ring 28.2.O-ring 29. Boa 30. Entrance gap X. Axial direction

Claims

1. A temperature-controllable calender roller (1) for producing electrode tracks using a dry electrode process, comprising: The roller has a roller body (2) and two roller journals (3) extending outward from the end faces of the roller body (2). a fluid channel arrangement (4) for temperature control of the roller body (2), the fluid channel arrangement (4) having a central bore (5) extending axially at least partially through the roller body (2) and through at least one of the roller journals (3), and a plurality of temperature control channels (6) distributed around the circumference of the roller body (2), extending below and parallel to the surface of the roller body and fluidically coupled to the central bore (5); an inlet line (7) and an outlet line (8) for a thermal fluid connected to said fluid channel arrangement (4), said inlet line (7) having a supply pipe (9) extending at least partially into said central bore (5) for introducing said thermal fluid into said fluid channel arrangement (4), said outlet line (8) having said inlet line (7) and said outlet line (8) fluidly coupled to an outlet gap (10) of said fluid channel arrangement (4) formed between an outside of said supply pipe (9) and an inner diameter of said central bore (5); The temperature-controllable calender roller (1).

2. 2. The temperature-controllable calender roller (1) according to claim 1, wherein the inlet line (7) and the outlet line (8) open into the same roller journal (3) of the calender roller (1), the temperature control channel (6) being fluidically connected to the supply pipe (9) via a number of inlet channels (11) and to the outlet gap (10) via a number of outlet channels (12), the inlet channels (11) opening into the central bore (5) at a first mouth area (13) facing opposite the inlet lines (7) and the outlet channels (12) opening into the outlet gap (10) at a second mouth area (14).

3. 3. The temperature-controllable calender roller (1) according to claim 2, wherein the outlet (24) of the supply pipe (9) extends axially into the central bore (5) beyond the mouth opening (13) of the inlet channel (11).

4. 4. The temperature-controllable calender roller (1) according to claim 1, wherein the central bore (5) is a through hole extending through both the roller journal (3) and the roller body (2), and the supply pipe (9) extends into the central bore (5) up to a region of the roller journal (3) opposite the supply line (7).

5. 5. The temperature-controllable calender roller (1) according to any one of claims 2 to 4, wherein the first mouth area (13) is sealed from the second mouth area (14) by at least one sealing bushing (15) arranged between said areas on the outside of the supply pipe (9).

6. 6. The temperature-controllable calender roller (1) according to claim 5, wherein two spaced apart sealing bushings (15) are arranged on the outside of the supply pipe (9) between the first mouth area (13) and the second mouth area (14), whereby no thermal fluid is present in the area enclosed between the sealing bushings (15) between the outside of the supply pipe (9) and the inner diameter of the central bore (5).

7. 7. A temperature-controllable calender roller (1) according to claim 2, wherein an odd number of temperature-control channels (6), spaced parallel to one another in the roller rotation direction, are arranged between each inlet channel (11) and its assigned outlet channel (12), through which the thermal fluid is guided in the axial direction (X) and vice versa according to the number of temperature-control channels (6).

8. 8. A temperature-controllable calender roller (1) according to claim 7, wherein the temperature control channels (6) are each designed as through-holes guided through the roller body (2), and adjacent temperature control channels (6) are connected to each other by essentially tangentially extending axially sealed grooves (17) introduced into the end faces.

9. 9. The temperature-controllable calender roller (1) according to claim 8, wherein the roller body (2) has, in the region of the temperature-control channels (6) on both end faces of the roller body (2), an axial annular groove (18) into which a cover cap (20) having the grooves (17) and a bore (19) is inserted, the axial annular groove (18) being axially sealed using a sealing element (21).

10. 10. The temperature-controllable calender roller (1) according to claim 9, wherein the sealing element (21) essentially completely covers the end faces of the roller body (2), and the sealing element (21) has a thermal conductivity of less than 3 W / (m·K).

11. Temperature-controllable calender roller (1) according to any one of claims 4 to 10, wherein the central bore (5) is closed at an end opposite the supply line (7) using a cover (22).

12. 12. The temperature-controllable calender roller (1) according to any one of claims 2 to 11, wherein the inlet channels (11) extend in a first diagonal direction axially away from the inlet side and in a radial direction away from the central bore (5) and the outlet channels (12) extend in a second diagonal direction axially towards the inlet side and in a radial direction away from the central bore (5).

13. 13. The temperature-controllable calender roller (1) according to claim 1, wherein the fluid channel arrangement (4) has, at least in the region of the roller journal (3) which contains it, a thermal insulation element (23) which thermally shields the fluid channel arrangement (4) from the roller journal (3).

14. 14. The temperature-controllable calender roller (1) according to claim 13, wherein the heat insulating element (23) is made of a material having a thermal conductivity of less than 0.3 W / (m·K), such as PTFE.

15. 15. The temperature-controllable calender roller (1) according to claim 13 or 14, wherein the fluid channel arrangement (4) extends at least partially through both roller journals (3), the fluid channel arrangement (4) having, in the region of both roller journals (3), a thermal insulation element (23) for thermally insulating the fluid channel arrangement (4) with respect to each roller journal (3).

16. The temperature-controllable calender roller (1) according to any one of claims 13 to 15, wherein the at least one insulating element (23) is inserted in the central bore (5) in the form of an insulating sleeve lining the central bore (5).

17. A process for manufacturing electrode tracks, comprising the steps of: providing a powder electrode precursor material and at least one calender roller, said calender roller having a fluid channel arrangement (4) for temperature control of said calender roller (1); - heating said calender roller (1) by directing a fluid through said fluid channel arrangement (4); contacting said calender roller (1) with said powder electrode precursor material; The process comprising:

18. 20. The process of claim 17, wherein the fluid is an oil.

19. 19. The process of claim 17 or 18, wherein the fluid is maintained at a temperature of from 30°C to 200°C.

20. 19. The process of claim 17 or 18, wherein the fluid is maintained at a temperature of from 60°C to 150°C.

21. 19. The process of claim 17 or 18, wherein the fluid is maintained at a temperature of from 90°C to 120°C.

22. 18. The process according to claim 17, wherein a cooling medium is guided through the fluid channel arrangement (4) to cool the calender roller (1), the temperature of the cooling medium being kept lower than the temperature of the calender roller (1).

23. A dry electrode manufactured by the process of any one of claims 17 to 22.

24. 24. The dry electrode of claim 23 having a thickness tolerance of less than 1 μm.

25. A process for manufacturing a calender roller (1), the method comprising the steps of: Manufacturing one or more calender roller components; connecting said one or more calender roller components; Including, said one or more calender roller parts comprising at least one supply pipe (9), at least one temperature control channel (6), and at least one outlet line (8); The calender roller (1) has a first end and a second end, said at least one supply pipe (9) extending from said first end to said second end; The above process.

26. 26. The process of claim 25, wherein the one or more calender roller parts are manufactured by CNC machining, forging, investment casting, injection molding, die casting, additive manufacturing, or combinations thereof.

27. 26. The process of claim 25, wherein the one or more calender roller parts are connected by metal gas welding, arc welding, tungsten inert gas welding, flux core welding, soldering, mixing, gluing, or combinations thereof.

28. manufacturing at least one insulating sleeve (23) and connecting said insulating sleeve (23) to said one or more calender roller components, the at least one insulating sleeve (23) is manufactured by transfer molding, injection molding, melt molding, compression molding, vacuum forming, pultrusion, or a combination thereof; said at least one insulating sleeve (23) is connected to said one or more calender roller components by adhesive, mechanical fastening, or a combination thereof; 26. The process of claim 25.

29. manufacturing at least one insulation layer and connecting said insulation layer to said one or more calender roller components; the at least one insulating layer is manufactured by transfer molding, injection molding, melt molding, compression molding, vacuum forming, pultrusion, or a combination thereof; the at least one thermal insulation layer is connected to the one or more calender roller components by adhesive, mechanical fastening, or a combination thereof; 26. The process of claim 25.

30. the calender roller (1) has a surface, and further comprising treating the surface of the calender roller (1), the surface of the calender roller (1) being treated using a microetching process, a laser engraving process, a super-polishing process, or a combination thereof; 26. The process of claim 25.

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