Device and method for machining an electrode material

Abstract

The invention relates to a method and to a device (10) for machining an electrode material (12), wherein the electrode material (12) comprises a carrier film (14) having active material (16), wherein the device (10) comprises a laser unit (18) which is designed to generate a pulsed laser beam (20) and to focus on the active material (16) and / or the carrier film (14) such that a laser spot (22) is generated on the active material (16) and the active material (16) is removed.

Description

[0001] Title: Device and method for processing a

[0002] Electrode material

[0003] Description

[0004] The invention relates to a device for processing an electrode material having the features of claim 1 and to a method for processing an electrode material having the features of the independent claim.

[0005] In the electrode production for battery cells, carrier foils are usually used which are coated with an active material. For this purpose, the carrier foil and / or the active material can be subjected to several production steps. If defects occur during one of these production steps, the affected sections of the carrier foil can be

[0006] Active material can be sorted out as production waste. An entire coil can also be sorted out if, for example, there are mixing and / or material defects.

[0007] The disadvantage is that both the carrier film and the active material are treated as scrap and disposed of. This is costly and unsustainable.

[0008] It is therefore an object of the present invention to provide a device and a method for processing an electrode material, wherein the above disadvantages are eliminated.

[0009] The above object is achieved by a device for processing an electrode material having the features of claim 1. The electrode material comprises a carrier foil with active material. The active material can be arranged (e.g., coated) on one or both sides of the carrier foil.

[0010] The device comprises a laser device which is configured to generate a pulsed laser beam and to focus it on the active material and / or the carrier film in such a way that a laser spot, in particular a circular one, is generated on the active material and the active material is removed.

[0011] This allows the active material to be removed from the carrier film using simple means. The carrier film and the active material can be reused (if necessary, with additional processing). Disposal of production waste is unnecessary. This saves costs and makes electrode production more sustainable.

[0012] The device can be integrated into a roll-to-roll process. Furthermore, process control can be optimized because the roll-to-roll process of electrode production does not need to be interrupted. The device or the laser device can, for example, be arranged directly below or above the carrier film in a roll-to-roll process of electrode production. It is also conceivable that the device could be implemented as a stand-alone solution outside of the roll-to-roll process.

[0013] Particle emissions can be reduced. The use of chemical agents and the associated chemical contamination can be avoided. Likewise, delamination (i.e., the removal of the active material) can be implemented selectively.

[0014] The device can in particular be designed to dissolve or break the bond (bonding layer) between the active material and the carrier film by targeted laser irradiation.

[0015] Electrodes for a lithium-ion battery typically consist of a cathode and an anode. The cathode (positive) can comprise a metallic carrier foil made of, for example, aluminum. The active material of the cathode can be made of, for example, lithium cobalt oxide (LiCoO2), lithium iron phosphate (LiFePO4), lithium nickel cobalt manganese oxide (LiNiCoMnO2 or NCM), or lithium nickel cobalt oxide (LiNiCoO2 or NCA). The anode (negative) can comprise a metallic carrier foil made of, for example, copper or lithium. The active material of the anode can be made of, for example, graphite, silicon, or lithium titanate.

[0016] (Li4Ti5O12) may be formed.

[0017] The electrode material may also include, for example, binders, conductive carbon black, metal collectors and other additives.

[0018] Additives can be used, for example, to improve electrical conductivity. The active material, especially for lithium-ion batteries, can have a thickness of 50 to 200 pm (micrometers) for the cathode and 10 to 200 pm for the anode.

[0019] The diameter of the laser spot can be in a range from 15 pm (micrometers) to 5 mm (millimeters), in particular in a range from 30 pm to 70 pm for single mode and 100 pm to 300 pm for multi mode.

[0020] According to a further development of the device, the laser device can comprise a pulsed laser beam source (or a pulsed laser) and / or a GW (continuous wave) laser beam source (or a CW laser). In particular, the laser device can be configured to generate a pulsed laser beam using a GW laser beam source.

[0021] This allows the pulsed laser beam to be generated using simple means.

[0022] The laser device can be a ns (nanosecond) pulsed laser beam source, for example with an average power of 20 to 5000 W (watts), in particular 50 to 600 W, further in particular 100 to 600 W, further in particular 200 to 600 W, a pulse duration of 3 to 2000 ns, in particular 50 to 500 ns or 10 to 60 ns, and / or a repetition rate of 1 kHz

[0023] (kilohertz) to 10 MHz (megahertz), in particular 40 to 1600 kHz, (single-mode or multi-mode).

[0024] It is also conceivable that the laser device may comprise a ps (picosecond) or fs (femtosecond) pulsed laser beam source. The laser device may also comprise a VCSEL (vertical-cavity surface-emitting laser) laser beam source (or a surface emitter).

[0025] The laser device may comprise a CW laser beam source, which may be embodied as a single-mode laser. The laser device may comprise a CW laser beam source capable of generating a pulsed laser beam with a maximum repetition rate of 100 Hz (Hertz). The laser device may comprise a solid-state laser (e.g., fiber laser or disk laser) with an average laser power of 50 W to 12 kW, in particular 50 W to 2 kW.

[0026] The laser device may comprise an infrared laser having a wavelength in a range of 800 to 1200 nm (nanometers), in particular 1030 nm or 1070 nm.

[0027] Alternatively, the laser device may comprise a VIS laser with a visible wavelength, in particular of, for example, 515 nm (green).

[0028] The laser device can be configured to generate a pulsed laser beam with a pulse energy in a range of 4 pj (microjoules) to 500 mJ (single pulse), in particular 500 pj to 200 mJ (ns process) or 4 pj to 300 pj (ps / fs process), in particular 1 mJ (millijoules). The laser device can be configured to generate a pulsed laser beam with an average power in a range of 20 to 100 W (ps / fs process) or 60 to 1000 W

[0029] (ns process) to create.

[0030] The laser device may comprise a pulsed laser beam source configured to generate a pulsed laser beam having a pulse length in a range of 200 fs to 1 ps (microsecond), in particular 200 fs to 500 ns.

[0031] The laser device may comprise a pulsed laser beam source which may be configured for burst mode operation.

[0032] According to a further development of the device, the laser device can be configured such that the laser spot has a fluence in a range of 0.14 J / cm A 2 (joules per square centimeter) to 17.8 J / cm A 2 , in particular 1 .42 J / cm A 2 . In this case, fluence refers to the ratio of energy per area. Fluence refers specifically to the energy per laser spot or laser spot area.

[0033] In this way, the energy required for the removal process of the active material can be optimally introduced into the active material using simple means.

[0034] According to a further development of the device, the laser device can be configured such that the laser beam is a single-mode laser beam and, in particular, has a Gaussian or Gaussian-like beam profile. The single-mode laser beam can preferably have a beam parameter product in the range from 0.38 mm*mrad to 1 mm*mrad, preferably approximately 0.6 mm*mrad (millimeters times milliradians). With such a laser beam, the active material can be removed, in particular, layer by layer.

[0035] This allows the introduction of energy into the active material to be further optimized.

[0036] According to a further development of the device, the laser device can be configured such that the laser beam is embodied as a multi-mode laser beam, and in particular has a top-hat or quasi-top-hat beam profile. For example, the multi-mode laser beam can have a beam parameter product in the range of 4 mm*mrad to 16 mm*mrad, preferably approximately 6 mm*mrad. Such a laser beam can, in particular, be used to remove a bonding layer of the active material.

[0037] This allows the introduction of energy into the active material to be further optimized.

[0038] The device may comprise a scanner optics system for moving the laser spot and / or the laser beam. The scanner optics system may have an imaging ratio of 1:1 to 5:1, in particular of 1.5:1 to 2:1. Alternatively, the device may comprise a fixed optics system.

[0039] The device can comprise a (particularly optical) sensor device for position determination and / or monitoring. The sensor device can comprise a camera or be designed as a camera. According to a further development of the device, the device can comprise a collecting device for collecting the detached active material. The collecting device can comprise a container for receiving and storing the detached active material.

[0040] This allows the removed active material to be collected using simple means.

[0041] According to a further development of the device, the collecting device can be designed as a suction device.

[0042] This allows the collection of the active material to be optimized.

[0043] The above object is achieved by a method for processing an electrode material having the features of the independent claim. The electrode material comprises a carrier foil with active material. The active material can be arranged (e.g., coated) on one or both sides of the carrier foil.

[0044] The procedure includes the following steps:

[0045] Providing a device according to the above statements.

[0046] Generating and focusing a pulsed laser beam onto the active material and / or the carrier film such that the laser beam generates a laser spot, in particular a circular one, on the active material. Moving the laser spot and / or the laser beam along a direction of movement over the active material and ablating the active material.

[0047] In the present case, moving the laser spot and / or the laser beam can mean a relative movement of the laser spot on the active material. In other words, the carrier film and / or the laser beam can be moved. For example, it is conceivable that the carrier film is moved and the laser beam is not moved (held in place). This results in a movement of the laser spot (relative to the carrier film). It is also conceivable that the carrier film and the laser beam are moved in the same way, so that the laser spot remains in the same position on the carrier film or on the active material or is not moved.

[0048] With regard to the advantages achievable with the method, reference is made to the relevant explanations of the device. The measures described in connection with the device and / or those explained below may serve to further refine the method.

[0049] The removal of the active material (delamination) can be carried out after one of the following process steps in the electrode production or assembly of battery cells: coating, drying, calendering, cutting of coils, cutting of the electrode sheets.

[0050] The movement of the laser spot and / or the laser beam can be implemented depending on the thickness and / or composition of the active material. The movement of the laser spot and / or the laser beam can be implemented at a feed rate in a range of 0.1 to 30 m / s (meters per second), in particular in a range of 4 to 20 m / s.

[0051] The laser spot can be used with an area rate in a range of 1 to 10 cm 2 / s (square centimetres per second), especially 6.5 cm 2 / s, along the direction of movement.

[0052] To remove the active material, the laser spot can be moved over the same position at least once, in particular at least twice (one pass or several passes).

[0053] According to a further development of the method, the method may comprise the step:

[0054] Moving the laser spot and / or the laser beam in such a way that a series of laser spots, in particular consecutive ones, is generated along the direction of movement. Two adjacent laser spots can overlap in a laser spot overlap region. The laser spot overlap region can have an area of ​​0% to 99%, in particular 50% to 99%, of the area of ​​a single laser spot.

[0055] This allows the removal of the active material to be further optimized.

[0056] According to a further development of the method, the method may comprise the step:

[0057] Moving the laser spot and / or the laser beam in such a way that a plurality of, in particular temporally successive, rows of, in particular temporally successive, laser spots are generated. The rows can be arranged parallel to one another. Two adjacent rows can overlap in a row overlap region. The row overlap region can have an area of ​​0% to 80%, in particular of 20% to 50%, of the area of ​​an individual row.

[0058] This allows the removal of the active material to be further optimized.

[0059] According to a further development of the method, the method may comprise the step:

[0060] Collecting, in particular vacuuming, the removed active material. This can be achieved in particular by means of the collection device.

[0061] This allows the active material to be collected using simple means.

[0062] According to a further development of the method, the method may comprise the step:

[0063] Reuse of the carrier film and / or the collected, particularly vacuumed, active material.

[0064] Reprocessing the carrier film and / or the collected, especially vacuumed, active material is also conceivable. This can save costs and make electrode production more sustainable.

[0065] Further features, details and advantages of the invention will become apparent from the wording of the claims and from the following description of exemplary embodiments with reference to the drawings. They show:

[0066] Fig. 1 is a schematic representation of an apparatus for processing an electrode material when generating a series of laser spots and

[0067] Fig. 2 is a schematic representation of the device according to Figure 1 when generating several rows of laser spots.

[0068] In the following description and in the figures, corresponding components and elements bear the same reference symbols. For the sake of clarity, not all reference symbols are shown in all figures.

[0069] Figure 1 shows a schematic representation of a device 10 for processing an electrode material 12 while generating a row 30 of laser spots 22.

[0070] The electrode material 12 comprises a carrier foil 14 with active material 16. In the present case, the active material 16 is applied or coated on only one side of the carrier foil 14. It is also conceivable that the active material 16 can be applied or coated on both sides of the carrier foil 14. The device 10 comprises a laser device 18 which is configured to generate a pulsed laser beam 20 and to focus it onto the active material 16 and / or the carrier foil 14 in such a way that a laser spot 22 is generated on the active material 16 and the active material 16 is ablated.

[0071] In the present case, a plurality of laser spots 22 are arranged in a row 30 along a direction of movement 28. Two adjacent laser spots 22 overlap in a laser spot overlap region 32. The laser spot overlap region 32 can have an area of ​​0% to 99%, in particular of 50% to 99%, more particularly of 83%, of the area of ​​an individual laser spot 22.

[0072] The laser device 18 may comprise a pulsed laser beam source and / or a CW laser beam source.

[0073] The laser device 18 can be configured such that the laser spot 22 has a fluence in a range of 0.14 J / cm A 2 to 17.8 J / cm A 2 , in particular 1 .42 J / cm A 2 , has .

[0074] The laser device 18 can be configured such that the laser beam 20 is a single-mode laser beam with a beam parameter product in a range from 0.38 to 1 mm*mrad, in particular from 0.6 mm*mrad. The laser beam 20 can, in particular, have a Gaussian or Gaussian-like beam profile.

[0075] The laser device 18 can be configured such that the laser beam 20 is formed as a multi-mode laser beam with a beam parameter product in the range of 4 mm*mrad to 16 mm*mrad, preferably of approximately 6 mm*mrad.

[0076] The laser beam 20 may have a tophat or quasi-tophat beam profile.

[0077] The device 10 may comprise a collecting device 24 for collecting removed active material 16. The collecting device 24 may be designed as a suction device 26.

[0078] Figure 2 shows a schematic representation of the device 10 according to Figure 1 when generating several rows 30 of laser spots 22.

[0079] In the present case, several rows 30 are arranged parallel to one another. Two adjacent rows 30 overlap in a row overlap region 34. The row overlap region 34 has an area of ​​0% to 80%, in particular of 20% to 50%, more particularly of 33%, of the area of ​​an individual row 30.

[0080] In the following, a method for processing an electrode material 12 is described with reference to Figures 1 and 2, wherein the electrode material 12 comprises a carrier film 14 with active material 16. The method comprises the following steps:

[0081] Providing a device 10 according to the above embodiments. The device 10 can in particular be the device 10 shown in Figures 1 and 2.

[0082] Generating and focusing a pulsed laser beam 20 onto the active material 16 and / or the carrier film 14 such that the laser beam 20 generates a laser spot 22 on the active material 16.

[0083] Moving the laser spot 22 and / or the laser beam 20 along a movement direction 28 over the active material 16 and ablating the active material 16. For this purpose, the laser spot 22 can be moved once or multiple times over the same position (one or more passes).

[0084] The movement of the laser spot 22 and / or the laser beam 20 can be implemented such that a row 30 of, in particular, temporally successive laser spots 22 is generated along the direction of movement 28. In this case, two adjacent laser spots 22 can overlap in a laser spot overlap region 32. The laser spot overlap region 32 can have an area of ​​0% to 99%, in particular of 50% to 99%, further in particular of 83%, of an area of ​​an individual laser spot 22 (cf. Figure 1).

[0085] The movement of the laser spot 22 and / or the laser beam 20 can be implemented in such a way that a plurality of, in particular temporally successive, rows 30 of, in particular temporally successive, laser spots 22 are generated. The rows 30 can be arranged parallel to one another. Two adjacent rows 30 can overlap in a row overlap region 34. The row overlap region 34 can have an area of ​​0% to 80%, in particular of 20% to 50%, more particularly of 33%, of an area of ​​an individual row 30 (cf. Figure 2). The method can comprise the step:

[0086] Collecting, in particular sucking up, the removed active material 16. In the present case, the removed active material is sucked up by means of the collecting device 24, which is designed as a suction device 26. This is indicated in Figures 1 and 2 by a thick arrow.

[0087] The method may comprise the step of:

[0088] Reusing the carrier film 14 and / or the collected, in particular vacuumed, active material 16. Reprocessing the carrier film 14 and / or the collected, in particular vacuumed, active material 16 is also conceivable.

Claims

Patent claims 1. Device (10) for processing an electrode material (12) wherein the electrode material (12) comprises a carrier film (14) with active material (16), wherein the device (10) comprises a laser device (18) which is configured to generate a pulsed laser beam (20) and to focus it onto the active material (16) and / or the carrier film (14) such that a laser spot (22) is generated on the active material (16) and the active material (16) is ablated.

2. Device (10) according to claim 1, characterized in that the laser device (18) comprises a pulsed laser beam source and / or a CW laser beam source.

3. Device (10) according to claim 1 or 2, characterized in that the laser device (18) is configured such that the laser spot (22) has a fluence in a range of 0.14 J / cm² A 2 to 17.8 J / cm² A 2.

4. Device (10) according to one of the preceding claims, characterized in that the laser device (18) is configured such that the laser beam (20) is designed as a single-mode laser beam, and in particular has a Gaussian or Gaussian beam profile.

5. Device (10) according to one of claims 1 to 3, characterized in that the laser device (18) is configured such that the laser beam (20) is used as a multi-mode laser beam is formed, and in particular has a tophat or quasi-tophat beam profile.

6. Device (10) according to one of the preceding claims, characterized in that the device (10) includes a collection facility (24) for collecting removed active material (16).

7. Device (10) according to the preceding claim, characterized in that the collecting device (24) is designed as a suction device (26).

8. Method for processing an electrode material (12) , wherein the electrode material (12) comprises a carrier film (14) with active material (16), comprising the steps: Providing a device (10) according to any one of the preceding claims; Generating and focusing a pulsed laser beam (20) onto the active material (16) and / or the carrier film (14) such that the laser beam (20) generates a laser spot (22) on the active material (16); Moving the laser spot (22) and / or the laser beam (20) along a direction of movement (28) over the active material (16) and removing the active material (16) .

9. The method of claim 8, characterized in that the method comprises the step of: Moving the laser spot (22) and / or the laser beam (20) such that a series (30) of, in particular, successive laser spots (22) is generated along the direction of movement (28), wherein two adjacent laser spots (22) overlap in a laser spot overlap area (32), wherein the laser spot overlap area (32) has an area of ​​0% to 99%, in particular 50% to 99%, of an area of ​​a single laser spot (22).

10. The method of claim 8 or 9, characterized in that the method comprises the step of: Moving the laser spot (22) and / or the laser beam (20) such that several, in particular temporally successive, rows (30) of, in particular temporally successive, laser spots (22) are generated, wherein the rows (30) are arranged parallel to each other, wherein two adjacent rows (30) overlap in a row overlap area (34), wherein the row overlap area (34) has an area of ​​0% to 80%, in particular of 20% to 50%, of an area of ​​a single row (30).

11. Method according to one of claims 8 to 10, characterized in that the method comprises the step: Collection, in particular absorption, of the removed active material (16) .

12. Method according to one of claims 8 to 11, characterized in that the method comprises the step: Reusing the carrier film (14) and / or the collected, especially absorbed, active material (16) .

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