Reverse lamination process for a battery slurry coating

Abstract

A method of forming an electrode, the method comprising: applying an active layer to a transfer device configured to move the active layer onto a current collector, the active layer comprising at least one binder, at least one active material, and at least one solvent; heating the active layer to evaporate the at least one solvent and draw the at least one binder to an outer surface of the active layer; and after heating the active layer, applying the active layer to the current collector, the outer surface in contact with the current collector.

Description

INTRODUCTION

[0001] The information provided in this section is intended to provide a general context for the disclosure. Work by the presently named inventors, to the extent described in this section, as well as aspects of the description that may not be prior art at the time of filing, are neither expressly nor impliedly acknowledged as prior art to the present disclosure.

[0002] The present disclosure relates to battery cells and, more particularly, to methods and systems for coating electrodes with an active layer.

[0003] Electric vehicles (EVs), such as battery electric vehicles (BEVs), hybrid vehicles, and / or fuel cell vehicles, comprise one or more electric machines and a battery system comprising one or more battery cells, modules, and / or packs. Each battery includes electrodes with current collectors coated with active material. A current control system is used to control the charging and / or discharging of the battery system during charging and / or driving. SUMMARY

[0004] The present disclosure includes, in various aspects, a method of manufacturing an electrode. The method includes: applying an active layer to a transfer device configured to move the active layer onto a current collector, wherein the active layer comprises at least one binder, at least one active material, and at least one solvent; heating the active layer to evaporate the at least one solvent and draw the at least one binder to an outer surface of the active layer; and after heating the active layer, applying the active layer to the current collector, wherein the outer surface is in contact with the current collector.

[0005] In further features, the present disclosure includes drying the active layer with a dryer after the active layer is applied to the current collector.

[0006] In further features, heating the active layer to evaporate the at least one solvent comprises heating the transfer device that transfers heat to the active layer.

[0007] In further features, the present disclosure further includes heating the active layer with a heater adjacent to the transfer device.

[0008] In further features, the present disclosure includes heating the active layer present on the transfer device by circulating a heating fluid through the transfer device.

[0009] In further features, the present disclosure includes heating the active layer present on the transfer device with heat generated by induction coils.

[0010] In further features, the present disclosure includes heating the active layer present on the transfer device with heat generated by an electrically conductive cover on the transfer device.

[0011] In further features, the present disclosure includes applying the active layer to the transfer device by applying the active layer to a conveyor belt mounted on a roller of the transfer device.

[0012] In further features, the present disclosure further includes heating the active layer with a heater adjacent to the conveyor belt.

[0013] In further features, the present disclosure includes, after heating the active layer to evaporate the at least one solvent and attract the at least one binder to an outer surface of the active layer, applying the active layer to both a first side and a second side of the current collector, wherein the outer surface is in contact with the current collector and the first side is opposite the second side.

[0014] The present disclosure also includes, in various features, a system for applying an active layer to a current collector to form an electrode. The system includes: a transfer device configured to move the active layer onto the current collector; a coating device configured to apply the active layer to the transfer device, wherein the active layer comprises at least one binder, at least one solvent, and at least one active material; a heating device configured to heat the active layer prior to applying the active layer to the current collector to evaporate the at least one solvent and draw the at least one binder to an outer surface of the active layer.

[0015] In further features, after heating the active layer by the heater, the transfer device is configured to move the active layer onto the current collector with the outer surface in contact with the current collector; and the system further includes a dryer configured to heat the active layer after applying the active layer to the current collector.

[0016] In further features, the transmission device comprises a roller.

[0017] In further features, the heater is enclosed in the transmission device.

[0018] In further features, the heater includes openings defined within the transfer device configured to receive a heated fluid.

[0019] In further features, the heater comprises a conductive layer on an outer surface of the transmission device.

[0020] In further features, the transfer device is a first roller, the system further comprising a second roller opposite the first roller configured to apply pressure to apply an additional active layer to the current collector.

[0021] The present disclosure also provides, in various features, a system for applying an active layer to a current collector to form an electrode. The system includes: a conveyor belt configured to move the active layer onto the current collector; conveyor rollers configured to drive the conveyor belt; a coating device configured to apply the active layer to the conveyor belt, wherein the active layer is in slurry form and comprises at least one binder and at least one solvent, at least one active material, and at least one conductive additive; and a heating device configured to heat the active layer prior to applying the active layer to the current collector to evaporate the at least one solvent and draw the at least one binder to an outer surface of the active layer.After the active layer is heated by the heater, the conveyor belt is configured to move the active layer onto the current collector with the outer surface in contact with the current collector.

[0022] In further features, the heater is located adjacent to the conveyor belt to heat the active layer prior to deposition of the active layer on the current collector.

[0023] Other features include the heating incorporated into the conveyor rollers.

[0024] Further areas of applicability of the present disclosure will become apparent from the detailed description, claims, and drawings. The detailed description and specific examples are provided for purposes of illustration only and are not intended to limit the scope of the disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The present disclosure will be more fully understood from the detailed description and the accompanying drawings, in which: Fig. 1 is a cross-sectional side view of an exemplary battery cell including current collectors coated with active layers in accordance with the present disclosure; Fig. 2 is a perspective view of an example of a prismatic battery cell including current collectors coated with active layers according to the present disclosure; Fig. 3 is a perspective view of another example of a prismatic battery cell including current collectors coated with active layers according to the present disclosure; Fig. 4A and Fig. 4B illustrates an exemplary system for applying an active layer to a current collector according to the present disclosure; Fig. 5 illustrates another system according to the present disclosure for applying an active layer to a current collector; Fig. 6 illustrates another system according to the present disclosure for applying an active layer to a current collector; Fig. 7 illustrates another system according to the present disclosure for applying an active layer to a current collector; and Fig. 8 illustrates an exemplary method according to the present disclosure for applying an active layer to a current collector.

[0026] Reference symbols may be reused in the drawings to identify similar and / or identical elements. DETAILED DESCRIPTION

[0027] The present disclosure provides various methods for coating a battery current collector with an active layer to form an electrode. The active layer comprises one or more active materials, at least one conductive additive, and at least one binder. The binder holds the active material and the conductive additive together, providing mechanical stability to the electrode. The binder also bonds the active layer to the current collector. When manufacturing slurry-based electrodes, the binder transitions from a liquid or gel-like state to a solid state when at least one solvent evaporates during the drying process. During this phase transition, the binder can be caused by capillary forces to migrate to an outer surface of the electrode coating.Capillary forces pull the binder toward the outer surface of the coating, traditionally resulting in areas on the inner surface of the coating at the coating / current collector interface that have relatively low binder content. Excessive migration of the binder can lead to uneven binder distribution, which can affect the bond strength between the electrode and current collector and can affect the mechanical properties of the electrode. The slurry can also be prepared without separate mixing of binder solutions. For example, a slurry can be mixed directly without first mixing the binder solution (this is common in pilot lines and larger plants). The slurry can also contain no conductive additives, a conductive additive, or combinations of conductive additives.Non-conductive additives may also be included, such as dispersants and / or viscosity modifiers.

[0028] With regard to the present disclosure, the active layer slurry is first coated onto a suitable transfer device, such as a roller or conveyor belt, at elevated temperature, rather than being coated directly onto the current collector. During this application step, at least one binder migrates from the coating-roller interface to an outer surface of the coating, creating a binder-rich surface. The coating is then laminated "inverted" onto the current collector: the binder-rich top surface of the coating, which was facing outward (or upward), becomes the underside at the interface between the coating and the current collector. This application method can reduce both drying time and drying space. Furthermore, the method can increase adhesion strength, allowing relatively thick electrodes to be formed.However, since the binder is also not electrically conductive, moving the binder to the current collector minimizes the non-conductive effect of the binder because the non-conductive property of the binder is balanced by the conductive current collector.

[0029] With reference now to Fig. 1 illustrates a battery cell 10 according to the present disclosure. The battery cell 10 can be configured for use in any suitable application, such as any suitable automotive or non-automotive application. The battery cell 10 includes C cathode electrodes 20, A anode electrodes 40, and S separators 32 arranged in a predetermined order in a stack 12 housed in a housing 48. C, A, and S are integers each greater than one. In some examples, A = C+1. The C cathode electrodes 20-1, 20-2, ..., and 20-C include active cathode layers 24 disposed on one or both sides of cathode current collectors 26. The A anode electrodes 40-1, 40-2, ..., and 40-A include active anode layers 42 disposed on one or both sides of the anode current collectors 46.

[0030] With reference now to Fig. 2, a prismatic battery cell 100 includes a housing 110. In some examples, the housing 110 has a rectangular cross-section. The prismatic battery cell 100 includes external terminals 112 and 114 and a vent cap 116. A stack 115 of the C cathode electrodes 20, the A anode electrodes 40, and the S separators 32 is disposed within the housing 110. The anode current collectors 46 and / or the cathode current collectors 26 include external tabs laser-welded to internal terminals that contact the external terminals 112 and 114 of the battery cell 10.

[0031] With reference to Fig. 3, a prismatic battery cell 200 includes a housing 210 and inner terminals 224 and 226 disposed at opposite ends of the housing 210. A stack 240 of the C cathode electrodes, the A anode electrodes, and the S separators is disposed within the housing 210. The cathode current collectors and / or the anode current collectors each include outer tabs 310 and 410 extending therefrom. The outer terminal tabs 310 and 410 are laser welded to inner surfaces of the respective inner terminals 224 and 226, as further described herein.

[0032] In some examples, the active cathode layers 24 and / or the active anode layers 42 comprise coatings that include one or more active materials, one or more conductive fillers / additives, and / or one or more binders. Examples of active materials for the cathode include, but are not limited to, lithium nickel manganese cobalt oxide (LiNi x Mny Co 1-x-y O2), lithium cobalt oxide (LiCoO2), lithium manganese oxide (LiMn2O4), and lithium iron phosphate (LiFePO4). Graphite is an example active anode material. Example conductive materials include, but are not limited to, carbon black, graphite, carbon nanotubes, graphene, conductive polymers such as polyaniline or polypyrrole, aluminum, copper, and carbon nanofibers. Example binders include, but are not limited to, polyvinylidene fluoride (PVDF), polyacrylic acid (PAA), carboxymethylcellulose (CMC), styrene-butadiene rubber (SBR), polyethylene oxide (PEO), and polyvinyl alcohol (PVA).

[0033] At least one binder is dissolved in at least one solvent to form a binder solution. The binder solution is mixed with the active materials and the conductive additives to form a slurry. The slurry is coated onto the current collectors 26, 46 in a roll-to-roll process as described herein. In some examples, the cathode current collectors 26 and / or the anode current collectors 46 comprise a foil layer, which may comprise a perforated foil or mesh. In some examples, the current collectors are made of copper, stainless steel, brass, bronze, zinc, aluminum, and / or alloys thereof. The current collectors 26 may also be made of any other material that is electrochemically stable within the operating voltage range of the electrode 20-1, 40-1.In some examples, outer tabs connected to the current collectors of the anode electrodes and cathode electrodes are positioned on opposite sides of the battery stack or on the same side of the battery stack, as shown below.

[0034] Fig. 4A-7 illustrate various systems according to the present disclosure for applying the active layers to the electrodes. Although Fig. 4A-7 illustrate systems for applying the active cathode layer 24 to the cathode current collector 26, the systems of the present disclosure are configured to apply the active anode layer 42 to the anode current collector 46 in the same manner.

[0035] With particular reference to Fig. 4A and Fig. 4B, a system 510A according to the present disclosure includes a first roller 520 and a second roller 530 opposite the first roller 520. The first roller 520 includes an outer surface 522, and the second roller 530 includes an outer surface 532. The cathode current collector 26 is in contact with the outer surface 532 of the second roller 530, and the second roller 530 is configured to rotate to move the cathode current collector 26 within the system 510A. The first roller 520 and the second roller 530 may be replaced by other suitable transfer devices, such as a conveyor belt, a moving track, etc.

[0036] The system 510A further includes a coating unit 540 configured to apply the active cathode layer 24 to the outer surface 522 of the first roller 520. The coating unit 540 may be any suitable coating unit, such as a slot die coating unit. The active cathode layer 24 may also be applied in any other suitable manner, such as with a suitable reverse decimal deposition system, as long as an outer surface 50 of the active layer 24 is ultimately applied to the current collector 26.

[0037] When applied to the outer surface 522, the active layer 24 includes the outer surface 50 and an inner surface 52 opposite the outer surface 50. The inner surface 52 of the active layer 24 is in contact with the outer surface 522 of the first roller 520. Thus, the outer surface 50 of the active layer 24 is on a side of the active layer 24 opposite the first roller 520. The first roller 520 is configured to rotate and apply the active layer 24 to the current collector 26 between the first roller 520 and the second roller 530. Adjacent to the first roller 520 is a blade scraper 552 configured to facilitate separation of the active layer 24 from the current collector 26. The first roller 520 may also be coated with a suitable non-stick coating to facilitate removal of the active layer 24.

[0038] The active layer 24 is applied as a wet slurry to the outer surface 522 of the first roller 520. The system 510A heats the active layer 24 by any suitable means to evaporate the solvent from the slurry before the active layer 24 is transferred to the current collector 26. During evaporation, capillary forces cause the binder to migrate from the inner surface 52 of the active layer 24 to the outer surface 50. This makes the outer surface 50 a binder-rich surface. Further rotation of the first roller 520 applies the active layer 24 to the current collector 26 so that the binder-rich outer surface 50 directly contacts the current collector 26. Thus, the binder-rich outer surface 50, which originally faced outward on the first roll 520, becomes a bottom layer at an interface between the active layer 24 and the current collector 26 to bond the active layer 24 to the current collector 26.The current collector 26 with the active layer 24 thereon is then transferred to the dryer 550, which further dries the active layer 24 to remove any remaining solvent. The dryer 550 can be any suitable dryer, such as a drying oven.

[0039] As previously mentioned, the active layer 24 is heated in the form of a slurry before being applied to the current collector 26. The active layer 24 may be heated in any suitable manner. For example, and as in the exemplary system 510B of Fig. 5, the first roller 520 may include induction coils 570 configured to be connected to any suitable power source. The electrical current applied to the induction coils 570 heats the coils 570, thereby heating the first roller 520 and the active layer 24 deposited thereon. The induction coils 570 may be configured to heat the first roller 520 through electromagnetic induction. For example, the induction coils 570 may be uniformly disposed on an inner surface of the first roller 520. Alternating currents are charged, then a magnetic line of force is created, and the eddy current induced by this line of force flows on the outer surface 522 of the first roller 520 to heat the active layer 24.Heat pipes 572 may be positioned around the induction coils 570 to dissipate excess heat generated by the induction coils 570 and provide temperature control. The induction coils 570 may be located within or adjacent to the first roller 520.

[0040] The heat pipes 572 may alternatively be enclosed independently of the induction coils 570 and configured to accommodate any suitable material that can be heated. For example, any suitable heating fluid, such as, but not limited to, hot oil, water, steam, etc., may be circulated through the heat pipes 572 to heat the first roller 520, which in turn heats the active layer 24 deposited on the first roller 520. Furthermore, the first roller 520 may be coated with a suitable conductive material 534 and connected to a suitable power source such that, upon current flow through the conductive material 534, the temperature of the conductive material rises, thereby heating the active layer 24 deposited thereon. The first roller 520 may include one or more of the induction coils 570, the heat pipes 572, and the conductive material 534.

[0041] The active layer 24 may also be heated by a suitable external heat source before being applied to the current collector 26. For example, and as shown in Fig. As illustrated in Figure 5, a heating element 560 may be included and positioned adjacent to the first roller 520 to heat the active layer 24 before the active layer 24 is deposited onto the current collector 26. The heater 560 may be any suitable heat source. For example, the heater 560 may be an induction heater, a microwave heater, a heat flux generator, an infrared radiant heater (IR / NIR), a laser-induced drying, etc.

[0042] Fig. 6 illustrates an additional system 510C according to the present disclosure. The system 510C is configured to apply a first active layer 24A to a first side of the current collector 26 and a second active layer 24B to a second side of the current collector 26. The second active layer 24B may be the same or substantially the same as the first active layer 24A. In the system 510C, the coating unit is a first coating device 540A and a second coating device 540B is located adjacent to the second roller 530. The second coating device 540B may be identical to or substantially similar to the first coating device 540A. The second coating device 540B applies the second active layer 24B to the second side of the current collector 26 in the same manner as described above with respect to the first coating device 540A.The second active layer 24B is heated prior to deposition onto the current collector 26 in the same manner as described above with respect to heating the first active layer 24A. In addition to a first heater 560A for the first active layer 24A, a second heater 560B may be included to heat the second active layer 24B prior to deposition onto the current collector 26.

[0043] Fig. 7 illustrates another system 510D according to the present disclosure for heating the first active layer 24A and the second active layer 24B. The system 510D includes a first conveyor belt 570A extending around and rotated by first conveyor rollers 572A and a second conveyor belt 570B extending around and rotated by second conveyor rollers 572B. The first coating device 540A applies the first active layer 24A to the first conveyor belt 570A. The second coating device 540B applies the second active layer 24B to the second conveyor belt 570B. The first conveyor belt 570A with the first active layer 24A thereon is passed past a first heater 562A to heat the first active layer 24A before it is deposited on the current collector 26.The second conveyor belt 570B, with the second active layer 24B thereon, is passed past a second heater 562B to heat the second active layer 24B before it is deposited on the current collector 26. In addition to the first and second heaters 562A, 562B, the first conveyor roller 572A directly upstream of the first heating element 562A and the second conveyor roller 572B directly upstream of the second heating element 562B may be heated in any suitable manner, as described above with respect to the first and second rollers 520, 530. Although the system 510D illustrates that both sides of the current collector 26 are coated with the first and second active layers 24A, 24B, the system 510D may be configured such that only one side of the current collector 26 is coated with the first active layer 24A or the second active layer 24B.

[0044] The present disclosure further provides various binder activations and surface treatments of the current collector 26 to facilitate adhesion of the active layers 24, 24A, 24B to the current collector 26. For example, adhesion may be provided by a primer applied to the outer surfaces 522, 532 of the first roller 520 and / or the second roller 530. Any suitable conductive polymer primer may be included to increase adhesion and reduce interfacial conductivity. Suitable conductive polymers include, but are not limited to, a conductive polyvinylidene fluoride, polyethylene, carboxymethylcellulose, and styrene-butadiene rubber. The primer may be applied either as a wet coat for direct lamination or as a dry coat activated by hot rolling to achieve adhesion.The dry coating can be thermally activated using laminating rolls 520, 530, or another set of hot rolls. Adhesion can also be achieved by applying a suitable solvent by spraying the solvent onto the current collector 26 prior to applying the active layer 24, 24A, 24B. Suitable solvents include, but are not limited to, the following: N-methyl-2-pyrrolidone, dimethyl sulfoxide, gamma-valerolactone, and deionized water.

[0045] Before the active layers 24, 24A, 24B are applied to the current collector 26, the current collector 26 may be treated to remove contaminants by any suitable means. For example, the current collector 26 may be subjected to a suitable plasma treatment, such as an oxygen or air plasma treatment. Such treatments also etch the surface of the current collector 26 to increase its roughness and facilitate the interaction between the current collector 26 and the active layers 24, 24A, 24B.

[0046] To further facilitate the interaction between the current collector 26 and the active layers 24, 24A, 24B, pressure may be exerted by one or more of the rollers 520, 530, 572A, 572B to press the active layers 24, 24A, 24B onto the current collectors 26, thereby improving the interfacial contact of the active layers 24, 24A, 24B with the current collector 26 and reducing the volume of the active layers 24, 24A, 24B.

[0047] Fig.8 illustrates an exemplary method 710 according to the present disclosure for applying the active layer 24 (including the first active layer 24A and the second active layer 24B) to the current collector 26. The method 710 may be performed by any of the systems 510A, 510B, 510C, 510D of the present disclosure or by any other suitable system. The operation of the method 710 and the systems 510A, 510B, 510C, 510D may be performed or otherwise coordinated by any suitable controller 810. In block 712, the method 710 includes dissolving the binder in a solvent to form the electrode binder solution. In block 714, the binder solution is mixed with the active materials and the conductive additive to form the active layer 24, 24A, 24B in slurry form.In block 716, the active layer 24, 24A, 24B is applied in slurry form to the rollers 520, 530 or the conveyor belts 570A, 570B. In block 718, the slurry of the active layer 24, 24A, 24B is heated in a suitable manner, as described above, before being applied to the current collector 26. The active layer 24, 24A, 24B can be heated, for example, by heating the rollers 520, 530, 572A, 572B or by using heaters 560, 560A, 560B, 562A, 562B. By heating the active layer 24, 24A, 24B, the solvent evaporates and draws the binder to the outer surface 50 of the active layer 24, 24A, 24B, as explained above. In block 720, the active layer 24, 24A, 24B is applied to the current collector 26 with the outer surface 50 in contact with the current collector 26. The outer surface 50 is a binder-rich surface that facilitates bonding the active layer 24, 24A, 24B to the current collector 26.In block 722, the deposited active layer 24, 24A, 24B is further dried, such as with dryer 550, to evaporate any remaining solution.

[0048] The foregoing description is merely illustrative and is in no way intended to limit the disclosure, its application, or uses. The broad teachings of the disclosure may be embodied in a variety of forms. Therefore, while this disclosure includes specific examples, the true scope of the disclosure should not be limited thereto, since other changes will become apparent after studying the drawings, the patent specification, and the following claims. It is understood that one or more steps within a method may be performed in a different order (or simultaneously) without altering the principles of the present disclosure.Furthermore, although the embodiments are each described above as having specific features, any one or more of these features described with respect to one embodiment of the disclosure may be implemented and / or combined with features of any of the other embodiments, even if this combination is not explicitly described. In other words, the described embodiments are not mutually exclusive, and interchanging one or more embodiments remains within the scope of this disclosure.

[0049] Spatial and functional relationships between elements (e.g., between modules, circuit elements, semiconductor layers, etc.) are described using various terms, including "connected," "engaging," "coupled," "adjacent," "beside," "on top of," "over," "below," and "disposed." Where a relationship between first and second elements is not explicitly described as "direct" in the above disclosure, that relationship may be a direct relationship, with no other intervening elements between the first and second elements, or an indirect relationship, with one or more intervening elements (either spatial or functional) between the first and second elements.As used herein, the term “A, B and / or C” should be construed as logical (A ORed with B ORed with C) using a non-exclusive logical OR and should not be understood as “at least one of A, at least one of B and at least one of C”.

[0050] In the figures, the direction of an arrow, as indicated by the arrowhead, generally illustrates the flow of information (such as data or instructions) of interest to the illustration. For example, if element A and element B exchange a plurality of pieces of information, but the information sent from element A to element B is relevant to the illustration, the arrow may point from element A to element B. This unidirectional arrow does not imply that no other information is sent from element B to element A. Further, for information sent from element A to element B, element B may send requests or acknowledgments for the information to element A.

[0051] In this application, which includes the definitions below, the term "module" or the term "controller" may be replaced by the term "circuit". The term "module" may refer to, be a portion of, or include: an application-specific integrated circuit (ASIC), a digital, analog, or mixed analog / digital discrete circuit, a digital, analog, or mixed analog / digital integrated circuit, a combinational logic circuit, a field-programmable gate array (FPGA), processor circuitry (common, dedicated, or group) that executes code, memory circuitry (common, dedicated, or group) that stores code executed by the processor circuitry, other suitable hardware components that provide the described functionality, or a combination of some or all of the foregoing components, such as in a system on a chip.

[0052] The module may include one or more interface circuits. In some examples, the interface circuits may include wired or wireless interfaces connected to a local area network (LAN), the Internet, a wide area network (WAN), or combinations thereof. The functionality of any given module of the present disclosure may be distributed among multiple modules connected via interface circuits. For example, multiple modules may enable load balancing. In another example, a server module (also referred to as a remote or cloud module) may perform some functions on behalf of a client module.

[0053] The term "code," as used above, may include software, firmware, and / or microcode and may refer to programs, routines, functions, classes, data structures, and / or objects. The term "common processor circuit" includes a single processor circuit that executes code from multiple modules, in part or in whole. The term "group processor circuit" includes a processor circuit that, in combination with additional processor circuits, executes code from one or more modules, in part or in whole. References to multiple processor circuits include multiple processor circuits on discrete chips, multiple processor circuits on a single chip, multiple cores of a single processor circuit, multiple threads of a single processor circuit, or a combination thereof.The term "shared memory circuit" encompasses a single memory circuit that stores code from multiple modules, either individually or collectively. The term "group memory circuit" encompasses a memory circuit that, in combination with additional memories, stores code from one or more modules, either individually or collectively.

[0054] The term "memory circuit" is a subset of the term computer-readable medium. As used herein, the term "computer-readable medium" does not include transitory electrical or electromagnetic signals propagating through a medium (such as on a carrier wave); therefore, the term "computer-readable medium" can be considered tangible and non-transitory.Non-limiting examples of a non-transitory, tangible, computer-readable medium include non-volatile memory circuits (such as a flash memory circuit, an erasable programmable read-only memory circuit, or a mask read-only memory circuit), volatile memory circuits (such as a static random access memory circuit or a dynamic random access memory circuit), magnetic storage media (such as an analog or digital magnetic tape or a hard disk drive), and optical storage media (such as a CD, a DVD, or a Blu-ray Disc).

[0055] The devices and methods described in this application may be implemented, in part or in whole, by a special-purpose computer created by configuring a general-purpose computer to perform one or more specific functions contained in computer programs. The functional blocks, flowchart components, and other elements described above serve as software specifications that can be translated into computer programs through the routine work of a skilled technician or programmer.

[0056] The computer programs include processor-executable instructions stored on at least one non-transitory, tangible, computer-readable medium. The computer programs may also include or be based on stored data. The computer programs may include a basic input / output system (BIOS) that interacts with the hardware of the special-purpose computer, device drivers that interact with specific devices of the special-purpose computer, one or more operating systems, user applications, background services, background applications, etc.

[0057] The computer programs may comprise: (i) descriptive text to be parsed, such as HTML (Hypertext Markup Language), XML (Extensible Markup Language) or JSON (JavaScript Object Notation), (ii) assembly code, (iii) object code generated from the source code by a compiler, (iv) source code for execution by an interpreter, (v) source code for compilation and execution by a just-in-time compiler, etc. By way of example only, source code may be written using the syntax of languages including C, C++, C#, Objective-C, Swift, Haskell, Go, SQL, R, Lisp, Java®, Fortran, Perl, Pascal, Curl, OCaml, Javascript®, HTML5 (Hypertext Markup Language 5th Revision), Ada, ASP (Active Server Pages), PHP (PHP: Hypertext Preprocessor), Scala, Eiffel, Smalltalk, Erlang, Ruby, Flash®, Visual Basic®, Lua, MATLAB, SIMULINK and Python®.

Claims

[1] A method of manufacturing an electrode, the method comprising: Applying an active layer to a transfer device configured to move the active layer onto a current collector, the active layer comprising at least one binder, at least one active material, and at least one solvent; Heating the active layer to evaporate the at least one solvent and draw the at least one binder to an outer surface of the active layer; and after heating the active layer, applying the active layer to the current collector with the outer surface in contact with the current collector. [2] The method of claim 1, further comprising drying the active layer with a dryer after the active layer is applied to the current collector. [3] The method of claim 1, wherein heating the active layer to evaporate the at least one solvent comprises heating the transfer device that transfers heat to the active layer. [4] The method of claim 1, further comprising heating the active layer with a heater adjacent to the transfer device. [5] The method of claim 1, further comprising heating the active layer present on the transfer device by circulating a heating fluid through the transfer device. [6] The method of claim 1, further comprising heating the active layer present on the transfer device with heat generated by induction coils. [7] The method of claim 1, further comprising heating the active layer present on the transfer device with heat generated by an electrically conductive cover on the transfer device. [8] The method of claim 1, wherein applying the active layer to the transfer device comprises applying the active layer to a conveyor belt mounted on a roller of the transfer device. [9] The method of claim 8, further comprising heating the active layer with a heater adjacent to the conveyor belt. [10] The method of claim 1, further comprising, after heating the active layer to evaporate the at least one solvent and attract the at least one binder to an outer surface of the active layer, applying the active layer to both a first side and a second side of the current collector, the outer surface being in contact with the current collector and the first side being opposite the second side.

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