Methods and systems for coating a substrate for use in electrode production, for use in applications such as batteries

Abstract

A method of coating a substrate for use in electrode production is provided. The method includes the steps of: (a) providing the substrate; (b) applying a dry electrode coating to the substrate to provide a coated substrate; and (c) curing the coated substrate with a laser system.

Description

METHODS AND SYSTEMS FOR COATING A SUBSTRATE FOR USE IN ELECTRODE PRODUCTION, FOR USE IN APPLICATIONS SUCH AS BATTERIESCROSS-REFERENCE TO RELATED APPLICATION

[0001] This application claims the benefit of U.S. Provisional Application No. 63 / 602,350, filed November 22, 2023, the content of which is incorporated herein by reference.FIELD

[0002] The invention relates to methods and systems for coating a substrate for electrode production, for example, for use in applications such as batteries.BACKGROUND

[0003] Electrode manufacturing for batteries (and other applications) traditionally consists of spreading a viscous mixture (e.g., a "slurry") of solid particles and additives in a processing fluid onto thin metal foils or grids (e.g., a "current collector") followed by evaporation of the process fluid leading to a porous layer structure. In the final cell, the pores are filled with an electrolyte. Traditional processes using such wet coating techniques involve a lengthy curing time which substantially increases the cost of battery production (e.g., by requiring using large heating / curing systems). Electrode manufacturing processes often use heat lamps, which utilize large amounts of energy and / or floorspace.

[0004] It would be desirable to provide improved systems and methods for coating a substrate for electrode production (e.g., without the use of heat lamps).SUMMARY

[0005] According to an exemplary embodiment of the invention, a method of coating a substrate for use in electrode production is provided. The method includes the steps of: (a) providing the substrate; (b) applying a dry electrode coating to the substrate to provide a coated substrate; and (c) curing the coated substrate with a laser system.

[0006] According to other embodiments of the invention, the method recited in the immediately preceding paragraph may have any one or more of the following features: the dry electrode coating includes a dry powder mixture containing particles of (i) an active material and (ii) a fusible material; the laser system includes an area laser for irradiating the coated substrate; the laser system includes an area laser for irradiating the coated substrate, the area laser provides at least one of a (i) continuous laser beam, and (ii) a pulsed laser beam; the laser system includes a raster laser for irradiating the coated substrate; the laser system includes a raster laser for irradiating the coated substrate, the raster laser provides at least one of a (i) continuous laser beam, or (ii) a pulsed laser beam; the laser system is configured to provide laser energy, the laser energy being infrared or near-infrared; the laser system includes a plurality of lasers for curing the substrate in step (c); step (c) includes using the laser system to heat a roller of a calendering system to cure the dry electrode coating applied in step (b); step (c) includes curing the coated substrate with the laser system and another laser system, the laser system irradiating the substrate prior to reaching a roller of a calendering system, the another laser irradiating the roller; further including the step of (d) further curing the coated substrate with an oven; the substrate is configured for use in electrode production for battery cells; the substrate is configured for use in electrode production for supercapacitors; the substrate is configured for use in electrode production for fuel cells; the substrate is configured for use in electrode production for water splitting applications; the substrate is configured for use in electrode production for applications where electrodes are configured to be in contact with an electrolyte layer.

[0007] According to another exemplary embodiment of the invention, a system for processing a substrate for use in electrode production is provided. The system includes a dry electrode coating system for applying a dry electrode coating to the substrate to provide a coated substrate. The system also includes a laser system including a laser configured to cure the coated substrate.

[0008] According to other embodiments of the invention, the system recited in the immediately preceding paragraph may have any one or more of the following features: the dry electrode coating includes a dry powder mixture containing particles of (i) an active material and (ii) a fusible material; the laser system includes an area laser for irradiatingthe coated substrate; the laser system includes an area laser for irradiating the coated substrate, the area laser being configured to provide at least one of a (i) continuous laser beam, and (ii) a pulsed laser beam; the laser system includes a raster laser for irradiating the coated substrate; the laser system includes a raster laser for irradiating the coated substrate, the raster laser being configured to provide at least one of a (i) continuous laser beam or (ii) a pulsed laser beam; the laser system is configured to provide laser energy, the laser energy being infrared or near- infra red; the laser system includes a plurality of lasers for curing the substrate; further including a calendering system including a roller, wherein the laser system is configured to heat the roller of the calendering system to cure the dry electrode coating; further including a calendering system including a roller, and another laser for heating the roller, wherein the laser system is configured to irradiate a portion of the substrate prior to reaching the roller; further including an oven for further curing of the coated substrate after curing by the laser system; the substrate is configured for use in electrode production for battery cells; the substrate is configured for use in electrode production for supercapacitors; the substrate is configured for use in electrode production for fuel cells; the substrate is configured for use in electrode production for water splitting applications; the substrate is configured for use in electrode production for applications where electrodes are configured to be in contact with an electrolyte layer.BRIEF DESCRIPTION OF THE DRAWINGS

[0009] The invention is best understood from the following detailed description when read in connection with the accompanying drawings. It is emphasized that, according to common practice, the various features of the drawings are not to scale. On the contrary, the dimensions of the various features are arbitrarily expanded or reduced for clarity. Included in the drawings are the following figures :

[0010] FIG. 1 is a block diagram cross-sectional side view illustrating a system for processing a substrate for use in electrode production, the system including an area laser, in accordance with an exemplary embodiment of the invention;

[0011] FIG. 2 is a block diagram cross-sectional side view illustrating a system for processing a substrate for use in electrode production, the system including a plurality of lasers, in accordance with an exemplary embodiment of the invention;

[0012] FIG. 3 is a block diagram cross-sectional side view illustrating a system for processing a substrate for use in electrode production, the system including a raster laser, in accordance with an exemplary embodiment of the invention;

[0013] FIG. 4 is a block diagram cross-sectional side view illustrating a system for processing a substrate for use in electrode production, the system including a laser irradiating a roller, in accordance with an exemplary embodiment of the invention;

[0014] FIG. 5 is a block diagram cross-sectional side view illustrating a system for processing a substrate for use in electrode production, the system including an area laser and a laser irradiating a roller, in accordance with an exemplary embodiment of the invention ;

[0015] FIG. 6 is a block diagram cross-sectional side view illustrating a system for processing a substrate for use in electrode production, the system including a raster laser and a laser irradiating a roller, in accordance with an exemplary embodiment of the invention ;

[0016] FIG. 7 is a block diagram cross-sectional side view illustrating a system for processing a substrate for use in electrode production, the system including a laser system and an oven, in accordance with an exemplary embodiment of the invention; and

[0017] FIG. 8 is a flow diagram illustrating a method of coating a substrate for use electrode production, in accordance with an exemplary embodiment of the invention.DETAILED DESCRIPTION

[0018] In many binder-based dry electrode production processes, a curing step is usually conducted to thermally cure a typical polymer-based binder. This step is often performed with energy intensive infrared heat lamps, which are energy intensive and may have heat uniformity issues.

[0019] Certain methods described herein use a laser as the binder thermal curing or melting heat source. The laser may be applied, for example, as an area beam, as a fast raster pattern, and / or other embodiments.

[0020] In direct calender-based heat curing (e.g., using a hot roller), a thermal resistive heater inside a roller and / or a laser can be used to heat the roller. The laser can be applied as an area beam, as a fast raster pattern, and / or other embodiments. In certain embodiments, the laser can be applied externally to the roller and / or internally to the roller (e.g., as either an area laser beam and / or fast raster laser beam).

[0021] Certain embodiments of the invention may improve electrode yield (e.g., for use in battery cells) and reduce energy consumption. Certain embodiments of the invention may reduce operational cost and increase uniformity when using a laser for binder thermal curing or as a melting heat source.

[0022] As used herein, the term "dry coating" refers to a coating to be applied without a solvent and / or a coating configured to reduce (or eliminate) a drying process. Such a "dry coating" may refer to a dry powder mixture containing particles of an active material and particles of a meltable / fusible material (e.g., a binder, a polymeric binder, a polymer, polyvinylidene fluoride (PVDF), polytetrafluoroethylene (PTFE) and polysiloxanes, etc.) configured to act as an adhesive for the active material. Examples of active materials for a dry coating include (i) oxides of lithium and transition metals, (ii) phosphates of lithium and transition metals, (iii) carbonaceous materials, among others. In certain embodiments, the dry powder mixture may also include a conductivity additive (e.g., carbon black, porous carbon, carbon nanotubes, graphene, graphite, and carbon fibers).

[0023] As used herein, "curing" refers to a material curing operation that partially, or completely, cures a material (e.g., a coating, a dry-coating, a polymer, etc.).

[0024] Referring now to the drawings, FIG. 1 illustrates a system 100 for processing a substrate 102a for use in electrode production. Substrate 102a (e.g., a foil, etc.) is illustrated being supplied by a substrate source 102 (e.g., a roll, a spool, etc.) and supported by a support structure 112.

[0025] System 100 includes a coating system 104 (e.g., a dry electrode coating system) for applying a coating 104' (e.g., a dry electrode coating) to substrate 102a, thereby providing the illustrated coated substrate 102b. In certain embodiments, coating 104' is a dry electrode coating including a dry powder mixture containing particles of an active material and a fusible material. System 100 is illustrated including an enclosure 108.

[0026] System 100 also includes a laser system 106 configured to cure the coated substrate 102b. Laser system 106 includes an area laser for irradiating coated substrate 102b. The area laser may be configured to provide a continuous laser beam and / or a pulsed laser beam. Laser system 106 may be configured to provide infrared or nearinfrared laser energy.

[0027] Laser system 106 (e.g ., including an area laser) is illustrated providing an area laser beam 106' to cure (e.g., at least partially cure) applied coating 104' of coated substrate 102b, thereby providing a cured substrate 102c. Cured substrate 102c is illustrated moving through a calendering system 114, including a roller 116, in connection with a calendering process. After cured substrate 102c has been calendered and / or rolled, a calendered substrate 102d is provided. Calendered substrate 102d can be collected (e.g., re-rolled) at collection system 110 (e.g., a roll). Calendered substrate 102d may be later divided (e.g., cut) into portions to be used as electrodes (e.g., electrodes for battery applications or other applications).

[0028] Various systems are illustrated throughout the drawings that include elements similar to elements included in system 100, where like reference numerals denote like elements. Accordingly, the description of certain elements (e.g., coating system 104, support structure 112, etc.) or aspects of system 100 (in connection with FIG. 1) are largely applicable to the description of system 200 (of FIG. 2), system 300 (of FIG. 3), system 400 (of FIG. 4), system 500 (of FIG. 5), system 600 (of FIG. 6), and / or system 700 (of FIG. 7), except where expressly indicated otherwise (or where the context implicitly indicates otherwise). It should be understood that although certain steps are performed on the "top" side of a substrate throughout the drawings, the invention is not so limited; certain steps may be performed on the "bottom" side of the substrate insteadof, or in combination with, the "top" side of the substrate. Although system 100 is illustrated processing substrate 102a within enclosure 108, the invention is not so limited. Certain embodiments of the invention may not always include enclosure 108.

[0029] Referring now to FIG. 2, a system 200 for processing a substrate 102a for use in electrode production is illustrated. System 200 includes a laser system 206, including a plurality of lasers. Laser system 206 is illustrated including a laser 206a (e.g., an area laser), . . ., and a laser 206n (e.g., another area laser). It should be understood that laser system 206 may include more than two lasers (as indicated by the illustrated ellipsis ". . ." between laser 206a and laser 206n).

[0030] Laser system 206 is illustrated providing an area laser beam 206a', via laser 206a (e.g., an area laser), to at least partially cure applied coating 104' of coated substrate 102b. Laser system 206 is illustrated providing an area laser beam 206n', via laser 206n (e.g., an area laser), to further cure (at least partially) applied coating 104' of coated substrate 102b. After curing via laser 206n, cured substrate 102c has been provided. Cured substrate 102c is illustrated moving through roller 116 of calendering system 114, in connection with a calendering process. After cured substrate 102c has been calendered and / or rolled, calendered substrate 102d has been provided. Calendered substrate 102d can be collected at collection system 110 (e.g., a roll). Calendered substrate 102d may be later divided (e.g., cut) into portions to be used as electrodes (e.g., electrodes for battery applications or other applications).

[0031] Referring now to FIG. 3, a system 300 for processing substrate 102a for use in electrode production is illustrated. System 300 includes a laser system 306. Laser system 306 includes (or is) a raster laser configured to irradiate a portion of coated substrate 102b. The raster laser is configured to provide a continuous laser beam and / or a pulsed laser beam. Laser system 306 is illustrated providing laser energy 306' along the translational direction (e.g., along the x-axis) of coated substrate 102b, as indicated by the double arrow. However, it is understood that the raster laser of laser system 306 may move along different and / or additional directions. After curing (e.g ., at least partially) coated substrate 102b via laser system 306, cured substrate 102c has been provided.

[0032] Cured substrate 102c is illustrated moving through roller 116 of calendering system 114, in connection with a calendering process. After cured substrate 102c has been calendered and / or rolled, calendered substrate 102d has been provided. Calendered substrate 102d can be collected at collection system 110 (e.g., a roll). Calendered substrate 102d may be later divided (e.g., cut) into portions to be used as electrodes (e.g., electrodes for battery applications or other applications).

[0033] Referring now to FIG. 4, a system 400 for processing a substrate 102a for use in electrode production is illustrated. System 400 includes a laser system 406 configured to heat roller 116 of calendering system 114 to cure the dry electrode coating. Laser system 406 is illustrated applying a laser beam 406' to roller 116 of calendering system 114.

[0034] In contrast to certain embodiments described herein, system 400 is configured such that coated substrate 102b is cured and calendered simultaneously via roller 116 of calendering system 114 without providing a cured substrate (e.g., cured substrate 102c). As illustrated, roller 116 is heated (e.g., at least partially by laser system 406) and calenders coated substrate 102b, thereby curing and calendering coated substrate 102b substantially simultaneously. Thus, calendered substrate 102d has been provided and can be collected at collection system 110 (e.g., a roll). Calendered substrate 102d may be later divided (e.g., cut) into portions to be used as electrodes (e.g., electrodes for battery applications or other applications).

[0035] Referring now to FIG. 5, a system 500 for processing a substrate 102a for use in electrode production is illustrated. System 500 includes calendering system 114 including roller 116. System 500 also includes a laser system 506, including laser 506a and laser 506b. Laser 506a is illustrated as an area laser providing an area laser beam 506a'. Laser 506b is configured to heat roller 116 of calendering system 114 to cure the dry electrode coating. Laser 506b is illustrated providing laser energy 506b' to roller 116.

[0036] Referring now to FIG. 6, a system 600 for processing a substrate 102a for use in electrode production is illustrated. System 600 includes a laser system 606, including laser 606a and laser 606b. Laser 606a is illustrated as a raster laser providing alaser beam 606a'. Laser 606a is illustrated providing laser beam 606a' along the translational direction (e.g., along the x-axis) of coated substrate 102b, as indicated by the double arrow. However, it is understood that laser 606a (e.g., the raster laser) of laser system 606 may move along different and / or additional directions. Laser 606b of laser system 606 is illustrated applying a laser beam 606b' to roller 116 of calendering system 114.

[0037] Referring now to FIG. 7, a system 700 for processing a substrate 102a for use in electrode production is illustrated. System 700 includes laser system 706 (e.g ., including an area laser, a raster laser, etc.). System 700 includes an oven 718.

[0038] Laser system 706 is illustrated providing laser energy 706' (e.g., an area laser beam, a laser beam from a raster laser, a continuous laser beam, a pulsed laser beam, etc.) to at least partially cure applied coating 104' of coated substrate 102b, thereby providing a cured substrate 102c. Cured substrate 102c is illustrated moving through oven 718 to further cure cured substrate 102c, thereby providing cured substrate 102c'. Cured substrate 102c' is illustrated moving through calendering system 114, including roller 116, in connection with a calendering process. After cured substrate 102c' has been calendered and / or rolled, calendered substrate 102d has been provided. Calendered substrate 102d can be collected at collection system 110 (e.g., a roll). Calendered substrate 102d may be later divided (e.g., cut) into portions to be used as electrodes (e.g., electrodes for battery applications or other applications).

[0039] It should be understood that laser system 706 can include (or be) any of the laser systems described in connection with FIGS. 1-6.

[0040] FIG. 8 is a flow diagram of a method of coating a substrate for use in electrode production. As is understood by those skilled in the art, certain steps included in the flow diagram may be omitted; certain additional steps may be added; and the order of the steps may be altered from the order illustrated - all within the scope of the invention.

[0041] At Step 800, a substrate (e.g., substrate 102a of FIGS. 1-7) is provided. At Step 802, a dry electrode coating (e.g ., coating 104' of FIGS. 1-7) is applied to the substrate to provide a coated substrate (e.g., coated substrate 102b of FIGS. 1-7). AtStep 804, the coated substrate is cured with a laser system (e.g., laser system 106 of FIG. 1; laser system 206 of FIG. 2; laser system 306 of FIG. 3; laser system 406 of FIG. 4; laser system 506 of FIG. 5; laser system 606 of FIG. 6; and / or laser system 706 of FIG. 7). In certain embodiments, Step 804 includes using the laser system to heat a roller of a calendering system to cure the dry electrode coating applied in Step 802 (e.g., see FIGS. 4-6). In certain embodiments, the coated substrate is calendered and at least partially cured simultaneously. At optional Step 806, the coated substrate is cured with an oven (e.g., oven 718 of FIG. 7).

[0042] It should be understood that although the systems and methods of coating a substrate described herein are primarily described in connection with electrode production for use in battery cells, the invention is not so limited. For example, the systems and methods described herein can be used in connection with the production of electrodes (or other components) for many applications such as supercapacitors, fuel cells, water splitting, or other components utilizing electron exchange. Further, the systems and methods described herein can be used in connection with the production of electrodes (or other components) for any applications where electrodes are configured to be in contact with an electrolyte material.

[0043] Although the invention is illustrated and described herein with reference to specific embodiments, the invention is not intended to be limited to the details shown. Rather, various modifications may be made in the details within the scope and range of equivalents of the claims and without departing from the invention.

Claims

What is Claimed :

1. A method of coating a substrate for use in electrode production, the method comprising the steps of:(a) providing the substrate;(b) applying a dry electrode coating to the substrate to provide a coated substrate; and(c) curing the coated substrate with a laser system.

2. The method of claim 1 wherein the dry electrode coating includes a dry powder mixture containing particles of (i) an active material and (ii) a fusible material.

3. The method of claim 1 wherein the laser system includes an area laser for irradiating the coated substrate.

4. The method of claim 3 wherein the area laser provides at least one of a (i) continuous laser beam, and (ii) a pulsed laser beam.

5. The method of claim 1 wherein the laser system includes a raster laser for irradiating the coated substrate.

6. The method of claim 5 wherein the raster laser provides at least one of a (i) continuous laser beam, or (ii) a pulsed laser beam.

7. The method of claim 1 wherein the laser system is configured to provide laser energy, the laser energy being infrared or near-infrared.

8. The method of claim 1 wherein the laser system includes a plurality of lasers for curing the substrate in step (c).

9. The method of claim 1 wherein step (c) includes using the laser system to heat a roller of a calendering system to cu re the dry electrode coating applied in step (b).

10. The method of claim 1 wherein step (c) includes curing the coated substrate with the laser system and another laser system, the laser system irradiating the substrate prior to reaching a roller of a calendering system, the another laser irradiating the roller.

11. The method of claim 1 further comprising the step of (d) further curing the coated substrate with an oven.The method of claim 1 wherein the substrate is configured for use in electrode production for battery cells.

13. The method of claim 1 wherein the substrate is configured for use in electrode production for supercapacitors.

14. The method of claim 1 wherein the substrate is configured for use in electrode production for fuel cells.

15. The method of claim 1 wherein the substrate is configured for use in electrode production for water splitting applications.

16. The method of claim 1 wherein the substrate is configured for use in electrode production for applications where electrodes are configured to be in contact with an electrolyte layer.

17. A system for processing a substrate for use in electrode production, the system comprising : a dry electrode coating system for applying a dry electrode coating to the substrate to provide a coated substrate; and a laser system including a laser configured to cure the coated substrate.

18. The system of claim 17 wherein the dry electrode coating includes a dry powder mixture containing particles of (i) an active material and (ii) a fusible material.

19. The system of claim 17 wherein the laser system includes an area laser for irradiating the coated substrate.

20. The system of claim 19 wherein the area laser is configured to provide at least one of a (i) continuous laser beam, and (ii) a pulsed laser beam .

21. The system of claim 17 wherein the laser system includes a raster laser for irradiating the coated substrate.

22. The system of claim 21 wherein the raster laser is configured to provide at least one of a (i) continuous laser beam or (ii) a pulsed laser beam .

23. The method of claim 17 wherein the laser system is configured to provide laser energy, the laser energy being infrared or near-infrared.

24. The system of claim 17 wherein the laser system includes a plurality of lasers for curing the substrate.

25. The system of claim 17 further comprising a calendering system including a roller, wherein the laser system is configured to heat the roller of the calendering system to cure the dry electrode coating.

26. The system of claim 17 further comprising a calendering system including a roller, and another laser for heating the roller, wherein the laser system is configured to irradiate a portion of the substrate prior to reaching the roller.

27. The system of claim 17 further comprising an oven for further curing of the coated substrate after curing by the laser system .

28. The system of claim 17 wherein the substrate is configured for use in electrode production for battery cells.

29. The system of claim 17 wherein the substrate is configured for use in electrode production for supercapacitors.

30. The system of claim 17 wherein the substrate is configured for use in electrode production for fuel cells.

31. The system of claim 17 wherein the substrate is configured for use in electrode production for water splitting applications.

32. The system of claim 17 wherein the substrate is configured for use in electrode production for applications where electrodes are configured to be in contact with an electrolyte layer.

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