Continuous and semi-continuous methods of semi-solid electrode and battery manufacturing

Abstract

To provide systems and methods for continuously and / or semi-continuously manufacturing semi-solid electrodes and batteries incorporating semi-solid electrodes.SOLUTION: In some embodiments, a process of manufacturing a semi-solid electrode includes continuously dispensing a semi-solid electrode slurry onto a current collector, separating the semi-solid electrode slurry into discrete portions, and cutting the current collector to form a finished electrode.SELECTED DRAWING: Figure 7

Description

[Technical Field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims priority to and benefit of U.S. Provisional Patent Application No. 62 / 695,483, filed July 9, 2018, entitled "Continuous and Semi-Continuous Methods of Semi-Solid Electrode and Battery Manufacturing," the disclosure of which is incorporated herein by reference in its entirety.

[0002] FIELD OF THE INVENTION The embodiments described herein generally relate to systems and methods for continuous and / or semi-continuous manufacturing of semi-solid electrodes and batteries incorporating semi-solid electrodes. [Background technology]

[0003] Battery manufacturing methods typically involve coating a conductive substrate (i.e., current collector) with a slurry containing active material, conductive additives, and a binder dissolved or dispersed in a solvent. After the slurry is coated onto the metal substrate, it is dried (e.g., by evaporating the solvent) and polished to a specified thickness. Battery electrode manufacturing also generally involves material mixing, casting, polishing, drying, slitting, and processing (bending, rolling, etc.), depending on the battery architecture being constructed. Because electrodes are manipulated during assembly and to ensure the conductive network is in place, all components are compressed into a tightly packed assembly, for example, using a binder. However, the binder itself occupies space, can complicate processing, and can hinder ionic and electronic conductivity. Therefore, there is a need for improvements in electrochemical cell (e.g., battery) and electrochemical cell manufacturing, such as eliminating electrochemical cell components and / or reducing electrochemical cell packaging while maintaining the same energy storage capacity. Summary of the Invention

[0004] SUMMARY OF THE INVENTION

[0003] Embodiments described herein generally relate to systems and methods for continuous and / or semi-continuous manufacturing of semi-solid electrodes and batteries incorporating the semi-solid electrodes. In some embodiments, a process for manufacturing a semi-solid electrode includes continuously dispensing a semi-solid electrode slurry onto a current collector, separating the semi-solid electrode slurry into distinct portions, and cutting the current collector to form a finished electrode. [Brief explanation of the drawings]

[0005] [Figure 1] FIG. 1 illustrates process steps for manufacturing an electrode and optionally an electrochemical cell, according to an embodiment. [Figure 2] FIG. 2 illustrates a dispensing mechanism according to an embodiment. [Figure 3] FIG. 3 illustrates a dispensing mechanism according to an embodiment. [Figure 4] FIG. 4 illustrates a dispensing mechanism according to an embodiment. [Figure 5] FIG. 5 illustrates a process for manufacturing an electrode according to an embodiment. [Figure 6A] FIG. 6A is a photograph of a semi-solid electrode slurry deposited on a moving current collector where a portion of the current collector is pressed between two plates, according to an embodiment. [Figure 6B] FIG. 6B is a photograph of the current collector of FIG. 3A after the two plates have been moved apart to reveal the pressed portion of the current collector, according to an embodiment. [Figure 7] FIG. 7 is a schematic diagram of a system for semi-continuous or continuous manufacturing of semi-solid electrodes, according to embodiments. [Figure 8] FIG. 8 is a schematic diagram of a system for semi-continuous or continuous manufacturing of semi-solid electrodes, according to embodiments. [Figure 9] FIG. 9 is a schematic diagram of a system for semi-continuous or continuous manufacturing of semi-solid electrodes, according to embodiments. [Figure 10]FIG. 10 is a schematic diagram of a system for semi-continuous or continuous manufacturing of semi-solid electrodes, according to embodiments. [Figure 11] FIG. 11 is a schematic diagram of a system for semi-continuous or continuous manufacturing of semi-solid electrodes, according to embodiments. [Figure 12A] FIG. 12A illustrates process steps for fabricating an electrochemical cell, according to an embodiment. [Figure 12B] FIG. 12B illustrates process steps for fabricating an electrochemical cell, according to an embodiment. [Figure 12C] FIG. 12C illustrates a process step for fabricating an electrochemical cell, according to an embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0006] FIELD OF THE INVENTION

[0002] Embodiments described herein generally relate to systems and methods for continuous and / or semi-continuous manufacturing of semi-solid electrodes and batteries incorporating the semi-solid electrodes. Embodiments described herein generally relate to a method for manufacturing semi-solid electrodes that includes disposing a semi-solid electrode material on a current collector. In some embodiments, the method can include continuously dispensing a semi-solid electrode slurry onto a current collector, separating the semi-solid electrode slurry into separate portions, and cutting the current collector to form finished electrodes.

[0007] Conventional electrodes and conventional electrochemical cells are typically prepared by coating separate portions of a metal foil substrate with a thin (e.g., about 10 μm to about 200 μm) wet slurry, which is then dried and polished to the desired thickness. The slurry components in this process typically include the active material, a conductive additive, a binder, and a solvent (e.g., commonly N-methylpyrrolidone (NMP)). Once the solvent evaporates (in a drying oven over a transfer line), the binder is converted to an "adhesive" that holds all the solid particles together in a matrix bonded to the substrate. Electrodes are typically coated with the same material on both sides of the substrate.

[0008] There are two common battery design approaches: (1) wound and (2) stacked. In wound battery designs, electrode sheets are cut to the desired dimensions, then a separator is placed between them, wound into a spiral or jelly roll, and then impregnated with electrolyte and packaged appropriately (usually in a cylindrical or rectangular metal can) to provide containment and electrical connection. In stacked battery designs, electrode sheets may also be cut to the desired dimensions, but then a separator is placed between them and stacked. Thus, stacked cells consist of physically discrete electrode sheets rather than continuous electrodes (i.e., anode / cathode pairs) as in wound cells. The stacked assembly can then be impregnated with electrolyte and packaged, typically in either a pouch / bag, plastic box, or metal can, each of which is also referred to as a cell or battery casing, as described herein.

[0009] In conventional pouch packaging, the pouch serves several functions. One such function is to provide hermetic isolation of the battery materials from the environment. Thus, the pouch can help prevent leakage of hazardous materials, such as electrolyte solvents and / or corrosive salts, into the surrounding environment and can prevent water and / or oxygen from penetrating the cell. Other functions of the pouch include, for example, compression packaging of the inner layer, voltage insulation for safety and handling, and mechanical protection of the battery assembly.

[0010] Typical pouch materials may include, for example, laminates (e.g., multi-layer sheets) formed into two or three solid film-like layers and bonded together by adhesive. As used herein, the term "laminate" also refers to materials that are not chemically bonded to each other. The term "pouch" can also refer to layers of materials. For example, the layers may be in face-to-face contact with each other and bonded using other bonding methods, such as heat sealing. The inner layer may be a plastic layer, such as non-oriented polypropylene (CPP). The next or second layer may be a metal foil layer, such as aluminum or an aluminum alloy. In some pouch configurations, additional layers may be present. The additional layer may be a protective coating formed by a plastic, such as nylon. Metal foil can provide airtightness and is much less permeable to certain compounds, especially water, than plastic. The inner plastic layer may be thermally bonded to itself, which is a rule regarding pouch closure and electrical pass-through acceptance. In pouch closure, when the inner layers (e.g., CPP) of two pouch laminates are brought into physical contact and heat is applied, the layers melt and fuse, forming a robust seal if the processing conditions (e.g., power, temperature, duration) are appropriately selected. For example, if the sealing is performed in a closed loop, an internal volume isolated from the surrounding or external environment can be formed.

[0011] Some known electrochemical cells (e.g., batteries) can include a variety of shapes and / or sizes, can be based on a wide variety of implementing materials and internal architectures, can be passively or actively controlled, can be rechargeable or non-rechargeable, and / or can share certain common features that enable the conversion of chemical energy into electrical energy. Some known batteries can include a first electrode with a high electrochemical potential and a second electrode with a lower electrochemical potential compared to the first electrode. Each electrode can include an active material that participates in chemical reactions and / or physicochemical transformations during discharge due to favorable thermodynamic changes in material state that can result in the flow of current when a switch is closed. In some cases, two different conductive networks can allow the anode and cathode to be electrically connected for charge transfer to occur. A separator can be used to provide separation between the anode and cathode so that only ions can pass and prevent short circuits.

[0012] The manufacture of battery electrodes can be a complex and capital-intensive process and generally involves mixing materials, casting, polishing, drying, slitting, and processing (bending, rolling, etc.) depending on the battery architecture being constructed. Because the electrodes are manipulated during assembly and to ensure the conductive network is in place, all components are compressed into a tight assembly, for example, using a binder. However, the binder itself takes up space, can complicate processing, and can hinder ionic and electronic conductivity.

[0013] As used herein, the singular forms "a," "an," and "the" include plural referents unless the context clearly dictates otherwise. Thus, for example, the term "element" is intended to mean a single element or a combination of elements, and "material" is intended to mean one or more materials or a combination thereof.

[0014] The term "substantially" when used in connection with "cylindrical," "linear," and / or other geometric relationships is intended to convey that the structure so defined is nominally cylindrical, linear, etc. As an example, a portion of a support member described as "substantially linear" is intended to convey that while linearity of the portion is desired, some nonlinearity can occur in the "substantially linear" portion. Such nonlinearity can result from manufacturing tolerances or other practical considerations (e.g., pressure or force applied to the support member, etc.). Thus, a geometric structure modified by the term "substantially" includes such geometric characteristics within a tolerance of plus or minus 5% of the described geometric structure. For example, a "substantially linear" portion is intended to convey that linearity is desirable, but that ... It is the part that defines the axis or centerline that is within ±5% of the square root of the axis.

[0015] As used herein, the terms "set" and "plurality" can refer to multiple features or a single feature having multiple portions. For example, when referring to a set of electrodes, the set of electrodes can be considered as one electrode having multiple portions, or the set of electrodes can be considered as multiple separate electrodes. Furthermore, for example, when referring to multiple electrochemical cells, the multiple electrochemical cells can be considered as multiple separate electrochemical cells or one electrochemical cell having multiple portions. Thus, a set of portions or multiple portions can include multiple portions that are either continuous or discontinuous with each other. Multiple particles or multiple materials can also be made from multiple articles that are manufactured separately and later bonded together (e.g., via mixing, adhesive, or any suitable method).

[0016] As used herein, the term "z-direction" generally refers to a third direction where the longitudinal and lateral directions are the first and second directions. In other words, the z-direction refers to the depth or thickness of a feature, rather than its length or width.

[0017] As used herein, the terms "about" and "approximately" generally mean plus or minus 10% of the stated value, e.g., about 250 μm includes 225 μm to 275 μm, and about 1,000 μm includes 900 μm to 1,100 μm.

[0018] As used herein, the term "semi-solid" refers to a material that is a mixture of liquid and solid phases, such as, for example, a particle suspension, a colloidal suspension, an emulsion, a gel, or a micelle.

[0019] As used herein, the terms "activated carbon network" and "networked carbon" refer to the general qualitative state of an electrode. For example, an electrode with an activated carbon network (or networked carbon) is one in which the carbon particles within the electrode assume an individual particle morphology and arrangement relative to one another that promotes electrical contact and conductivity between the particles. Conversely, the terms "non-activated carbon network" and "non-networked carbon" refer to an electrode in which the carbon particles exist as individual particle islands or multi-particle agglomerate islands that may not be sufficiently connected to provide adequate electrical conduction through the electrode.

[0020] FIG. 1 shows a schematic diagram of a method 10 for continuously or semi-continuously manufacturing a semi-solid electrode. In some embodiments, the method 10 includes continuously dispensing a semi-solid electrode slurry onto a current collector 11 as the semi-solid electrode slurry passes through a conveying system. In some embodiments, the conveying system can be configured to continuously or semi-continuously convey the current collector past a fixed dispensing mechanism. In some embodiments, the dispensing mechanism can be adjustable and / or move relative to the current collector. In some embodiments, the fixed dispensing mechanism can be a nozzle configured to dispense the semi-solid electrode slurry at a precise predetermined rate onto specific areas of the current collector as the semi-solid electrode slurry passes through the fixed dispensing mechanism.

[0021] Dispensing a semi-solid slurry can generate significant forces on the delivery system. The force generated by dispensing a semi-solid slurry is proportional to the load of the semi-solid slurry (i.e., a load of semi-solid slurry with a higher viscosity generates a greater force on the delivery system). In some embodiments, the force acting on the delivery system can be greater than 2,000 lbf, greater than 2,500 lbf, greater than 3,000 lbf, or greater than 3,500 lbf. This force can cause mechanical deflections in the delivery system, regardless of how thoroughly the system is designed to limit deflections. These deflections can affect the casting gap between the dispensing mechanism and the current collector. This affects the thickness of the electrode. In some embodiments, deflections can reach 100 μm over the course of only 10 mm of movement of the current collector through the transport system. In some embodiments, the adjustable dispensing mechanism can move to counteract these deflections. In other words, the adjustable dispensing mechanism can move up and down (i.e., along the z-axis) to compensate for deflections caused by the forces of the dispensed slurry. In some embodiments, the dispensing mechanism can move up and down (i.e., in the z-direction) along the entire width of the electrode. In some embodiments, the dispensing mechanism can move up and down at an angle on the left side of the electrode so that the dispensing mechanism is lower on the left side of the electrode than on the right side of the electrode. In some embodiments, the dispensing mechanism can move up and down at an angle on the right side of the electrode so that the dispensing mechanism is lower on the right side of the electrode than on the left side of the electrode.

[0022] In some embodiments, the dispensing mechanism can move to control the casting gap between the dispensing mechanism and the current collector to an accuracy of less than 10 μm, less than 9 μm, less than 8 μm, less than 7 μm, less than 6 μm, less than 5 μm, less than 4 μm, less than 3 μm, less than 2 μm, or less than 1 μm. In some embodiments, the dispensing mechanism can move along the z-axis a distance of more than about 1 μm, more than about 5 μm, more than about 10 μm, more than about 20 μm, more than about 30 μm, more than about 40 μm, more than about 50 μm, more than about 60 μm, more than about 70 μm, more than about 80 μm, more than about 90 μm, or more than about 100 μm to ensure accuracy in electrode thickness. The dispensing mechanism can be adjusted very quickly to match the timing of the transport system's movements. In some embodiments, the reactive movement of the dispensing mechanism can occur in less than 0.5 seconds, less than 0.4 seconds, less than 0.3 seconds, less than 0.2 seconds, less than 0.1 seconds, less than 0.09 seconds, less than 0.08 seconds, less than 0.07 seconds, less than 0.06 seconds, less than 0.05 seconds, less than 0.04 seconds, less than 0.03 seconds, less than 0.02 seconds, or less than 0.01 seconds. For example, the casting gap can be changed from 150 μm to 200 μm in 0.1 seconds, and a 200 μm gap can be achieved with 1 μm accuracy. And, the casting gap can be changed from 200 μm to 175 μm in 0.1 seconds, and a 175 μm gap can be achieved with 1 μm accuracy. In some embodiments, servo-controlled movement can control the movement of the dispensing mechanism to control the casting gap to a desired level of accuracy. In some embodiments, beta gauge readings from recently manufactured electrodes can be used to determine the movement schedule of the dispensing mechanism. In some embodiments, the distribution mechanism can control the casting gap between the distribution mechanism and the current collector in the casting nozzle. In some embodiments, a blade in the casting nozzle can move up and down to control the casting gap between the distribution mechanism and the current collector. In some embodiments, the semi-solid electrode slurry can be configured to remain in a predetermined area once dispensed onto the current collector.

[0023] In some embodiments, electrodes comprising the semi-solid electrode slurries described herein can reduce the volume, mass, and cost contribution of inactive components relative to the active components, thereby increasing the commercial appeal of batteries fabricated with the semi-solid electrodes. In some embodiments, the semi-solid electrodes described herein are binder-free and / or do not use binders used in conventional battery manufacturing. Instead, the volume of the electrode typically occupied by the binder in conventional electrodes can be occupied by: 1) an electrolyte, which has the effect of reducing tortuosity and increasing the total salt available for ion diffusion, thereby countering the salt depletion effect typical of thick conventional electrodes when used at high rates; 2) an active material, which has the effect of increasing the charge capacity of the battery; or 3) a conductive additive, which has the effect of increasing the electronic conductivity of the electrode, thereby countering the high internal impedance of thick conventional electrodes. While not wishing to be bound by any particular theory, the reduced tortuosity and higher electronic conductivity of the semi-solid electrodes described herein result in superior rate capability and charge capacity of electrochemical cells formed from the semi-solid electrodes.

[0024] In some embodiments, the current collector comprises a conductive material that is not already distributed on a separate current collector. The current collector has a length defining a longitudinal axis and a width defined as the dimension perpendicular to the longitudinal axis. The current collector is configured to be transported through a conveying system (i.e., the direction of travel) along its longitudinal axis. In some embodiments, the width of the current collector can be substantially similar to the desired width or height of the current collector used in the finished semi-solid electrode. In some embodiments, the width of the current collector can be greater than about 101%, 105%, 110%, 120%, 130%, 140%, 150%, 175%, 200%, 300%, 400%, or 500% of the desired width or height of the current collector used in the finished semi-solid electrode.

[0025] In some embodiments, the current collector has a thickness of about 0.01 μm to about 100 μm, about 100 μm to about 100 μm, about 1 μm to about 95 μm, about 1 μm to about 90 μm, about 1 μm to about 85 μm, or about 1 μm to about 80 μm, including all values ​​and ranges therebetween. In some embodiments, the current collector has a thickness of less than about 500 μm, less than about 400 μm, less than about 300 μm, less than about 200 μm, less than about 100 μm, less than about 90 μm, less than about 80 μm, less than about 70 μm, less than about 60 μm, less than about 50 μm, less than about 45 μm, less than about 40 μm, less than about 35 μm, less than about 30 μm, less than about 25 μm, less than about 20 μm, less than about 19 μm, less than about 18 μm, less than about 17 μm, less than about 16 μm. less than about 15 μm, less than about 14 μm, less than about 13 μm, less than about 12 μm, less than about 11 μm, less than about 10 μm, less than about 9 μm, less than about 8 μm, less than about 7 μm, less than about 6 μm, less than about 5 μm, less than about 4 μm, less than about 3 μm, less than about 2 μm, less than about 1 μm, less than about 900 nm, less than about 750 nm, less than about 500 nm, or less than about 100 nm, including all values ​​and ranges therebetween.

[0026] The current collectors can be electronically conductive and electrochemically inert under the operating conditions of the cell. In some embodiments, the current collector materials can include copper, aluminum, and / or titanium for the negative current collector and aluminum for the positive current collector. In some embodiments, aluminum is used as the positive electrode current collector. In some embodiments, copper is used as the negative electrode current collector. In other embodiments, aluminum is used as the negative electrode current collector.

[0027] The semi-solid electrode slurry can be electrochemically configured for use in the anode and / or cathode. The semi-solid electrode slurry can include an active material in a liquid electrolyte. In some embodiments, the active material, which can be organic or inorganic, can include, but is not limited to, lithium metal, sodium metal, lithium metal alloys, gallium and indium alloys with or without dissolved lithium, molten transition metal chlorides, thionyl chloride, etc., or redox polymers and organics that are liquid under the operating conditions of the battery. The electrode formulation can include, for example, (1) an active material (i.e., a source and sink of ions and electrons), (2) carbon (or a mixture of carbons) or other material having the primary function of, but not necessarily exclusively, electronic conduction, and (3) an electrolyte (e.g., a solvent or solvent mixture and a salt) having the primary function of, but not necessarily exclusively, ionic conduction. The electrode formulation can optionally include other additives with specific intended chemical, mechanical, electrical, and / or thermal functions. The electrode formulation can include, for example, the active materials, compositions, and / or semi-solid suspensions described in U.S. Pat. No. 8,993,159, entitled "Semi-Solid Electrodes Having High Rate Capability," and U.S. Pat. No. 9,437,864, entitled "Asymmetric Battery Having a Semi-Solid Cathode and High Energy Density Anode," the entire disclosures of each of which are incorporated herein by reference.

[0028] In some embodiments, the semi-solid electrode slurry comprises a conductive additive, a stabilizing additive, and and / or gelling agents. Examples of semi-solid electrode slurries can be found in U.S. Patent Nos. 8,993,159, 9,178,200, 9,184,464, 9,203,092, and 9,484,569, the entire disclosures of which are incorporated herein by reference.

[0029] In some embodiments, electrodes and electrochemical cells fabricated directly with the semi-solid electrode slurry completely avoid the use of conventional binders and conventional electrode casting steps. Using a semi-solid electrode slurry also eliminates the need to inject an electrolyte into the electrode material, since the semi-solid electrode slurry already contains the electrolyte. Some advantages of this approach include, for example, (i) a simplified manufacturing process with less equipment (i.e., less capital intensive), (ii) the ability to fabricate electrodes of different thicknesses and geometries (e.g., by varying extrusion die slot dimensions or other process conditions), (iii) the processing of thicker (>100 μm) and higher areal charge capacity (mAh / cm2) electrodes, thereby reducing the volume, mass, and cost contribution of inactive components relative to the active material, and (iv) the elimination of binders, thereby reducing electrode twist and increasing ionic conductivity.

[0030] In some embodiments, the current collector can pass through the distribution mechanism at a velocity greater than about 1 meter per minute, greater than about 5 meters per minute, greater than about 10 meters per minute, greater than about 15 meters per minute, greater than about 20 meters per minute, greater than about 25 meters per minute, greater than about 30 meters per minute, greater than about 35 meters per minute, greater than about 40 meters per minute, greater than about 45 meters per minute, greater than about 50 meters per minute, greater than about 55 meters per minute, greater than about 60 meters per minute, greater than about 65 meters per minute, greater than about 70 meters per minute, greater than about 75 meters per minute, greater than about 80 meters per minute, greater than about 85 meters per minute, or greater than about 100 meters per minute, including all values ​​and ranges therebetween. In some embodiments, the speed at which the current collector passes the fixed dispense point can be between about 1 meter per minute and about 100 meters per minute, between about 5 meters per minute and about 80 meters per minute, between about 10 meters per minute and about 70 meters per minute, between about 20 meters per minute and about 60 meters per minute, between about 30 meters per minute and about 50 meters per minute, including all values ​​and ranges therebetween.

[0031] In some embodiments, the current collectors can be transported through the distribution mechanism using a transfer belt, a vacuum pallet, a vacuum conveyor, a belt conveyor, rollers, moving pans, pneumatic conveyors, hydraulic conveyors, vibrating conveyors, vertical conveyors, spiral conveyors, by pulling or pushing the current collectors across a surface having a low coefficient of friction, by any other suitable equipment or approach, or by a combination thereof. In some embodiments, the current collectors can be thin and highly deformable, so care must be taken not to wrinkle, fold, tear, bend, dent, or otherwise mishandle the current collectors during transport. In some embodiments, to help protect the current collectors from such damage, the current collectors can be placed on a pouch material before the semi-solid electrode slurry is placed on the current collector (e.g., step 11). In some embodiments, placing the current collectors on a pouch material before the semi-solid electrode slurry is placed on the current collectors can also help transport the current collectors through the distribution mechanism.

[0032] Method 10 further includes separating the semi-solid electrode slurry into distinct portions on current collector 12. In some embodiments, the semi-solid electrode slurry can be separated into distinct portions on current collector 12 by removing a portion of the continuously deposited semi-solid electrode slurry. In some embodiments, the semi-solid electrode slurry can be removed from current collector 12 by temporarily making a portion of the current collector unavailable to receive the deposited semi-solid electrode slurry thereon. 2. In some embodiments, the semi-solid electrode slurry can be separated into separate portions on the current collector 12 by varying the length of the current collector relative to the length of the continuously deposited semi-solid electrode slurry. In some embodiments, the semi-solid electrode slurry can be separated into separate portions on the current collector 12 by removing previously deposited occlusive material from the current collector after the semi-solid electrode slurry has been deposited. In some embodiments, the separate portions can be separate electrodes formed by first placing a mask material on at least a portion of the current collector and then placing the semi-solid electrode slurry on the masked current collector, and the mask material can then be removed to define the completed electrode or electrodes.

[0033] In some embodiments, the semi-solid electrode slurry can be separated into distinct portions on the current collector 12 by either sonication, laser ablation, doctor blading, irradiation, precision cutting, or a combination thereof. In some embodiments, the semi-solid electrode slurry can be separated into distinct portions on the current collector 12 by accelerating the current collector a distance through a distribution mechanism, causing uncoated portions of the current collector to form between each distinct portion of the semi-solid electrode slurry.

[0034] In some embodiments, as described above, the width of the current collector (the dimension perpendicular to the direction of movement of the current collector through the transport system) can be approximately equal to or greater than the width of the current collector used in the finished electrode. In some embodiments, the width of the current collector can accommodate separation of the deposited semi-solid electrode slurry into multiple electrode portions in the width direction. In other words, in some embodiments, separation of the semi-solid electrode slurry into separate portions on the current collector 12 can include separation of the semi-solid electrode slurry in two directions (parallel to the direction of movement of the current collector and perpendicular to the direction of movement of the current collector).

[0035] Method 10 further includes cutting the current collector between the separate portions of the semi-solid electrode slurry to form the finished electrode 13. In some embodiments, the current collector can be cut by separating contoured sections of the current collector along pre-drilled section lines. In some embodiments, the current collector can be cut using a laser (e.g., CO gas laser, high-power diode laser, fiber optic laser, etc.), drilling, plasma cutting, using a reciprocating blade, using a punch or press, pneumatic cutting, hydraulic cutting, using other methods known to those skilled in the art, or combinations thereof.

[0036] In some embodiments, each singulated current collector having a separate portion of the semi-solid electrode slurry disposed thereon can be considered a completed electrode. In some embodiments, the completed electrode can be placed on an electrically insulating material (e.g., a laminate pouch material) such that the current collector directly abuts the insulating material. In some embodiments, an adhesive can be used to hold the completed electrode on the insulating material. In some embodiments, as described above, the current collector can be pre-placed in the insulating material (e.g., a pouch material) such that singulating the current collector material also includes cutting the insulating material to form the completed electrode.

[0037] In some embodiments, the completed electrode can include an electrode tab electrically connected to the current collector and configured to input and output electrons to and from the electrode. In some embodiments, the electrode tab can extend beyond the current collector and / or insulating material. In some embodiments, the electrode tab can be electrically bonded to the current collector before the semi-solid electrode slurry is disposed on the current collector. In some embodiments, the cell can include integrated electrical tabs, which can eliminate the need for (i) separate tab components (e.g., electrical leads), (ii) connecting a dedicated tab to the current collector, and (iii) a dedicated tab sealing operation. Instead, in some embodiments, the electrical tab or lead can be provided as an extension of the current collector that is integral to the current collector. In some embodiments, the tab or lead can be electrically bonded to the current collector before the semi-solid electrode slurry is disposed on the current collector. The tabs can be defined by removing material from a larger area of ​​the current collector material, thereby defining the current collector and the tab or lead.

[0038] Method 10 optionally includes joining a completed electrode (e.g., a cathode) with a second completed electrode (e.g., an anode) interposed by a separator to form a completed electrochemical cell 14. In other words, once a completed electrode is singulated (e.g., according to step 13), it can be assembled into a completed electrochemical cell with a second completed electrode exhibiting the opposite redox reaction. In other words, the cathode and anode can be joined together with a separator disposed therebetween.

[0039] In some embodiments, a separator can be disposed between the anode and the cathode. In some embodiments, the separator can be bonded to at least one of the anode and the cathode by an adhesive. In some embodiments, one anode, one cathode, and one separator can be stacked together to form a unit cell assembly. Each unit cell assembly can also include conductive tabs (also called leads) for coupling the electrodes to an external circuit. Multiple unit cell assemblies are then stacked or arranged together to form a battery cell. In some embodiments, the number of unit cell assemblies in a battery cell can vary depending on, for example, the desired capacity and / or thickness of the resulting battery cell. These stacked unit cell assemblies are electrically parallel, and the respective tabs in each unit cell assembly are typically welded together via welding processes such as resistance welding, laser welding, ultrasonic welding, seam welding, and electric beam welding, among others.

[0040] In some embodiments, the prepared electrochemical cell can be vacuum-sealed in a prismatic pouch, which can provide airtight isolation of the electrochemical cell materials from the environment. Thus, the pouch can help prevent leakage of hazardous materials, such as electrolyte solvents and / or corrosive salts, into the surrounding environment and can prevent water and / or oxygen from penetrating into the cell. Other functions of the pouch can include, for example, compression packaging of the inner layers, voltage insulation for safety and handling, and mechanical protection of the electrochemical cell assembly. In some embodiments, electrolyte can be injected into the stacked unit cell assembly during vacuum pouch sealing, and the unit cell assembly and electrolyte can then be sealed in the pouch. In some embodiments, if the semi-solid electrode slurry already contains the desired total amount of electrolyte, no electrolyte is added during the pouch sealing step.

[0041] In some embodiments, the sealed battery cell can then be subjected to a formation process, in which an initial charging operation can be performed to form a stable solid electrolyte interphase (SEI), which can passivate the electrode-electrolyte interface as well as prevent side reactions. In some embodiments, several charge and discharge cycles can be performed to ensure that the battery's capacity meets required specifications. In some embodiments, a degassing step can be performed to release gases introduced or generated during the initial charging phase or during the electrochemical reactions in the battery formation step. The presence of trapped gas in the electrode generally reduces the electrode's conductivity and density, limits the amount of active electrochemical material that can be placed in the battery cell, and can cause dendrite growth, which can impair the battery performance of lithium batteries. In some embodiments, dendrite formation can lead to reduced cycle life and reduced overall safety performance. In some embodiments, a resealing step can be performed to reseal the battery cell after the trapped gas is released.

[0042] In some embodiments, semi-solid electrodes and electrochemical cells can be produced in a shorter period of time using the methods described herein compared to conventional electrochemical cell manufacturing methods. In some embodiments, a shorter duration can minimize electrolyte evaporation and / or degradation, reducing manufacturing costs and the factory footprint required for the same output of electrochemical potential.

[0043] 2 illustrates a dispensing mechanism 100 capable of controlling the length of an electrode casting gap T, according to embodiments. In some embodiments, a nozzle 110 can dispense electrode slurry 120 onto a current collector 130 disposed on a transport system 140, and the casting gap T can be controlled by movement of a nozzle blade 150. In some embodiments, the casting gap T can be controlled by independent movement of the nozzle blade 150 in the z-direction relative to the nozzle 110, the current collector 130, and the transport system 140. In some embodiments, the casting gap T can be controlled by moving both the nozzle 110 and the nozzle blade 150 in the z-direction relative to the current collector 130 and the transport system 140.

[0044] FIG. 3 illustrates a dispensing mechanism 200 capable of controlling the length of the casting gap T between the nozzle 210 and the current collector 230 on the transport system 240, according to embodiments. In some embodiments, the movement of the nozzle blade 250 in the z-direction can be controlled by a set of rollers 255. The rollers 255 can be pushed from either side by a servo system (not shown) that can push the nozzle blade 250 downward on the left side, the right side, or across the entire width of the nozzle blade 250. In some embodiments, only the left roller 255a can be engaged to lower the nozzle blade 250 only on the left side, so that the left side of the nozzle blade 250 is lower than the right side of the nozzle blade 250. In some embodiments, only the right roller 255b can be engaged to lower the nozzle blade 250 only on the right side, so that the right side of the nozzle blade 250 is lower than the left side of the nozzle blade 250. In some embodiments, both the left roller 255a and the right roller 255b can be engaged to lower the nozzle blade 250 along its entire width. In some embodiments, a set of springs 259 can provide a force to return the nozzle blade 250 to its original position after it has been lowered.

[0045] FIG. 4 illustrates a dispensing mechanism 300 capable of controlling the length of the casting gap T between the nozzle 310 and the current collector 330 on the transport system 340, according to embodiments. In some embodiments, the movement of the nozzle blade 350 in the z-direction can be controlled by a set of cams 357. The cams 357 can be controlled by a set of camshafts (not shown) that can rotate to push the nozzle blade 350 downward on the left side, the right side, or across the entire width of the nozzle blade 350. In some embodiments, only the left cam 357a can be engaged to lower the nozzle blade 350 only on the left side, such that the left side of the nozzle blade 350 is lower than the right side of the nozzle blade 350. In some embodiments, only the right cam 357b can be engaged to lower the nozzle blade 350 only on the right side, such that the right side of the nozzle blade 350 is lower than the left side of the nozzle blade 350. In some embodiments, both the left cam 357a and the right cam 357b can be engaged to lower the nozzle blade 350 along its entire width. In some embodiments, a set of springs 359 can provide a force to return the nozzle blade to its original position after it has been lowered.

[0046] Push-in method 5-8 illustrate a method for producing a semi-solid electrode in a continuous or semi-continuous manner. In some embodiments, the current collector material can be continuously moved from a current collector feeder onto a conveyor and passed through a distribution mechanism. In some embodiments, the current collector material can be continuously moved through a conveyor system. In some embodiments, the conveyor system can be moved parallel and / or perpendicular to the direction of conveyor movement. The conveyor system may include a series of plates configured to move relative to the direction of travel of the conveyor system. As used herein, plates refer to a plurality of planar structures configured to move relative to the direction of travel of the conveyor system and may also be pallets, sheets, covers, films, or other suitable structures. In some embodiments, the conveyor system may include a shuttle conveyor, a wire belt conveyor, a belt conveyor, a perforated conveyor, a spreader conveyor, a roller conveyor, a chain conveyor, or a combination thereof.

[0047] In some embodiments, a vacuum belt conveyor can be used to transport current collector material through a manufacturing system. Vacuum belt conveyors typically include a perforated belt and a slider bed with a sealed conveyor frame. In this manner, air can be drawn through the holes in the frame, creating a partial vacuum. Vacuum belt conveyors can be used to transport light and / or flat materials so that the material is held against the conveyor belt. Vacuum belt conveyors can be used to transport light and / or flat materials at higher speeds, which can increase production speeds. In some embodiments, a vacuum belt conveyor can be used to transport light and / or flat materials in a non-horizontal direction, such as vertically.

[0048] 6A and 6B, a portion of the continuous current collector can be inserted, pushed, pleated, folded, gathered, creased, bent, grouped, gathered, obscured, and / or excluded from deposition of electrode slurry material onto the continuous current collector. In other words, in some embodiments, a separate portion or multiple separate portions of the continuous current collector can be isolated and excluded from receiving electrode slurry material.

[0049] In some embodiments, a portion of the continuous current collector can be moved in a direction perpendicular to the direction of movement of the continuous current collector. In some embodiments, after moving a portion of the current collector away from the moving surface (e.g., downward), two edges of the intervening portion of the current collector can be moved together to completely isolate the intervening portion of the current collector.

[0050] In some embodiments, continuous current collectors can be moved across a series of abutting plates configured to open and close during continuous or semi-continuous manufacturing. In some embodiments, the plates can be configured to be approximately the same size as the completed electrochemical cell to minimize waste of semi-solid electrode slurry material. In some embodiments, the plates can be perforated or otherwise configured to allow a vacuum to be drawn across the entire surface of the plate so that the material can be held on the surface regardless of the plate's orientation. In some embodiments, the plates can be mounted on a rotating system so that the plates can accommodate the current collectors at one end of a conveyor line, transport the current collectors during deposition of electrode material onto the current collectors, and then return them toward the beginning of the conveyor line. In some embodiments, the plates can be cleaned or otherwise conditioned for reuse between the end of the conveyor line and the beginning of the conveyor line.

[0051] In some embodiments, a method for continuously or semi-continuously manufacturing a semi-solid electrode can include a first step in which a plate can be initially opened as a continuous current collector is placed on the plate. In some embodiments, the continuous current collector (i.e., foil) can be fed from a reel feeder, across one or more rollers, and onto a conveyor, as shown in Figures 7 and 8. In some embodiments, the continuous current collector can be substantially similar to the continuous current collector described above with respect to Figure 1.

[0052] In some embodiments, in the second step, a portion of the continuous current collector is The continuous current collector can be placed (e.g., inserted or pushed) between the two open plates by any suitable method, including, but not limited to, an extension rod, an air knife, a pusher wire, or other suitable method. In some embodiments, the continuous current collector can be slowed, paused, or stopped to facilitate placement of the continuous current collector portion between the two open plates. In some embodiments, the continuous current collector can be moved nonstop, and placement of the continuous current collector portion between the two open plates can be performed on the fly. In some embodiments, a flying pusher can be used, which can be configured to move at substantially the same speed as the continuous current collector while causing interposition of the continuous current collector portion between the plates. In some embodiments, a stationary pusher can be used, configured to push the continuous current collector portion between the plates as the continuous current collector passes through the stationary pusher. In some embodiments, a computer vision system can be configured to monitor the pushing step and precisely control the pusher, the plate movement, and the timing of pushing and unpushing. In some embodiments, the computer vision system may be a closed-loop computer vision system including a video camera, a processor, memory, a power supply, and a computer-readable medium configured to provide process feedback to an automated manufacturing system.

[0053] In some embodiments, in a third step, the two open plates can be moved into a closed configuration in which the two plates substantially abut one another and an intervening portion of the continuous current collector is held between the two plates. In some embodiments, closing the plates can hold the intervening portion of the continuous current collector between the plates. In some embodiments, the plates can have locking edges such that the locking edge of one plate can directly abut the locking edge of the adjacent plate to frictionally engage the current collector. In some embodiments, the locking edges can include a material that deforms to some extent when the plates close, which can increase how securely the portion of the continuous current collector is held between the plates in the third and fourth steps.

[0054] In some embodiments, in the fourth step, the semi-solid electrode slurry can be deposited onto the continuous current collector by a dispensing mechanism. As shown in FIG. 6A, the deposited semi-solid electrode slurry can be deposited onto the continuous current collector without being deposited on an intervening portion of the continuous current collector. In some embodiments, the deformable fixed edge can help reduce or eliminate loss of the semi-solid electrode slurry to the portion of the continuous current collector interposed between the two plates.

[0055] In some embodiments, the dispensing mechanism can be a nozzle configured to dispense the semi-solid electrode slurry at a precise predetermined rate onto a specific area of ​​the current collector as it passes through the dispensing mechanism, hi some embodiments, the semi-solid electrode slurry can be configured to remain in a predetermined area once dispensed onto the current collector.

[0056] In some embodiments, the semi-solid electrode slurry can be continuously or semi-continuously deposited onto the current collector using a parallel vertical tape casting / hybrid tape casting (VTC / HTC) station containing parallel slurry cartridges, as shown in Figure 7. In some embodiments, the semi-solid electrode slurry can be continuously or semi-continuously deposited onto the current collector using a casting station, as shown in Figure 8.

[0057] In some embodiments, the continuous current collector can be cut to obtain current collectors having the dimensions of the desired current collector in the finished electrode, as shown in Figure 8. In some embodiments, individual current collectors can be picked up from a web reel and placed on the conveyor system described above with respect to Figure 5. In some embodiments, individual current collectors can be placed on a press. The current collectors can be placed directly onto the plate, with the plates configured to create a distance between each current collector after opening and closing to remove them. In some embodiments, individual current collectors can be picked up from a web reel and placed onto the pouch material, with the pouch material configured to become at least a portion of the insulated outer coating of the completed electrochemical cell. In some embodiments, the pouch material can be a continuous pouch material and can be fed onto the plate from a roller. Without wishing to be bound by any particular theory, it may be easier to move and handle thin current collectors when they are placed (e.g., bonded) onto the pouch material than when they are handled individually. In some embodiments, the pouch material with the individual current collectors disposed on its surface can be fed onto a conveyor containing plates, with the plates in an open configuration. In some embodiments, the plates can be positioned and configured so that only the pouch material (without the current collector material) extends beyond the plates. In some embodiments, a pushing device (e.g., a flying tucker as described herein) can be used to place a portion of the pouch material between two plates, with the plates configured to be moved to a closed configuration to secure the portion of the pouch material between them. In some embodiments, when a portion of the pouch material is placed between two plates and isolated by closing the plates, the only surface of the pouch material remaining on the plates is the pouch material with the current collector bonded to it. In other words, the individual current collectors are bonded to the pouch material with a portion of the current collector material sandwiched between them, with a portion of the current collector sandwiched between the plates, and the remaining surface is the continuous surface of the current collector. In some embodiments, a semi-solid electrode slurry can then be continuously or semi-continuously placed on the current collector, and the plates can be opened to separate the individual completed electrodes.

[0058] In some embodiments, in an optional fifth step, the dispensed semi-solid electrode slurry can be spread to a specific thickness across a continuous current collector using, for example, a doctor blade, a roller, a polishing process, a moving press, or a combination thereof. In some embodiments, the semi-solid electrode slurry can be deposited onto a subset of the current collectors (e.g., in the center of the continuous current collector). In some embodiments, the optional fifth step can be performed at an elevated temperature. In some embodiments, a plastic film (e.g., a polyethylene terephthalate film) can be placed on the semi-solid electrode slurry before the polishing step so that the semi-solid electrode slurry remains substantially disposed on the current collector rather than adhering to a polishing roller or other polishing device.

[0059] In some embodiments, in the sixth step, the plates can be opened to expose intervening portions of the continuous current collector and separate the separate portions of the semi-solid electrode slurry on the continuous current collector. In some embodiments, the plates can be opened by manually forcing the plates open and / or by speeding up the continuous current collector. In some embodiments, as shown in FIG. 6B, the separate portions of the semi-solid electrode slurry can be configured to have well-structured (i.e., clean or straight) lines on two or more sides of the separate portions of the semi-solid electrode slurry. In some embodiments, each separate portion of the semi-solid electrode slurry on the current collector can be considered an electrode of an electrochemical cell.

[0060] In some embodiments, a scoring device can be used to score the semi-solid electrode slurry before opening the plates to expose separate portions of the semi-solid electrode slurry. In some embodiments, the scoring device can be used to score the semi-solid electrode slurry at a location that generally corresponds to the interface between the plates to aid in clean separation of the semi-solid electrode slurry when the plates are opened. In some embodiments, the scoring mechanism can include a tensioned wire. In some embodiments, the tensioned wire can be heated or vibrated to aid in scoring the semi-solid electrode slurry. In some embodiments, the scoring mechanism can include a movable blade. In some embodiments, the scoring mechanism can include a directed fluid or air jet. In some embodiments, the scoring device can include an ultrasonic knife configured to separate the semi-solid electrode slurry into separate portions. In some embodiments, the act of opening the plates can separate the separate portions of the semi-solid electrode slurry without the need for a scoring device. In some embodiments, the plates can be moved to the open configuration by moving one of the plates away from the other, while the other plate remains in a fixed relative position. In some embodiments, the plates can be moved to the open configuration by simultaneously moving both plates away from the other. In some embodiments, the plates can be moved to the open configuration by first moving one interfacial corner of the plate away from the corresponding corner of the opposite plate, and then moving the other interfacial corner of the plate away from the second corresponding corner of the opposite plate. In other words, the plates can be rotated away from the adjacent plates, which is useful for creating a clean break in the semi-solid electrode slurry.

[0061] In some embodiments, in the seventh step, the current collector can be cut perpendicular to the direction of travel of the current collector between each separate portion of semi-solid electrode slurry to form individual electrodes. In some embodiments, the current collector can be cut using a laser (e.g., a CO gas laser, a high-power diode laser, a fiber optic laser, etc.), drilling, plasma cutting, using a reciprocating blade, using a punch or press, pneumatic cutting, hydraulic cutting, using other methods known to those skilled in the art, or a combination thereof. In some embodiments, as shown in FIG. 8, individual electrodes can be picked up from a conveyor (e.g., using a robotic arm) and placed on a different conveyor. In some embodiments, if the completed electrode has not yet been bonded to a pouch material, the individual electrodes can be bonded to the pouch material in this step. In some embodiments, the individual electrodes can be polished as needed to reduce the thickness of the semi-solid electrode slurry on the current collector and / or to reduce defects. In some embodiments, a beta gauge, such as a moving web thickness and / or weight measurement system, can be used to ensure proper and consistent z-direction thickness of the semi-solid electrode slurry on the current collector. In some embodiments, a video camera and computer processor can be used to visually inspect the finished electrodes and discard any defective electrodes, for example, using a computer vision program.

[0062] This design provides for electrochemical cells to adopt a variety of form factors, which allows them to be constructed in specialized shapes and sizes for specific applications. In some embodiments, the shape and design of the cathode and anode can determine the shape and design of the resulting battery. In some embodiments, the use of various electrode materials, e.g., semi-solid components, separators, and compartment volumes, determines the power and energy capabilities of the battery.

[0063] In some embodiments, in an optional eighth step, a singulated electrode (e.g., a cathode) can be paired with a separator and a second singulated electrode (e.g., an anode) to form an electrochemical cell. In some embodiments, the formed electrochemical cell can be sealed on at least one edge within the pouch material. In some embodiments, the formed electrochemical cell can be sealed on at least two edges within the pouch material. In some embodiments, the formed electrochemical cell can be sealed on at least three edges within the pouch material. In some embodiments, the formed electrochemical cell can be sealed on at least four edges within the pouch material. In some embodiments, the semi-solid electrode slurry may contain less electrolyte than the finished electrode will contain when ultimately formed. In some embodiments, at least a portion of the electrolyte may be added during or after the eighth step. In some embodiments, after sealing the electrochemical cell in the pouch material, the electrochemical cell may be cycled through one or more charge / discharge cycles. In some embodiments, after the first cycle of the electrochemical cell, the pouch material may be punctured to release gas formed during the first cycle. In some embodiments, after evacuating the sealed electrochemical cell pouch, a heat sealer may be used to reseal the pouch along the fourth edge.

[0064] Material forcing and masking In some embodiments, a continuous or semi-continuous method for producing a semi-solid electrode can include a combination of one of the methods described above with respect to Figures 5-8 and an additional step of physically placing a portion of the current collector between two plates to define at least one edge of the finished electrode. In some embodiments, such a hybrid method can include a first step in which the plates can be initially opened as the continuous current collector is placed on the plates. In some embodiments, the continuous current collector can be fed from a reel feeder, across one or more rollers, and onto a conveyor. In some embodiments, the continuous current collector can be substantially similar to the continuous current collector described above with respect to Figure 1.

[0065] In some embodiments, in a first step, a portion of a continuous current collector can be placed (eg, sandwiched or forced) between two open plates, for example, using an air knife.

[0066] In some embodiments, in a second step, the two open plates can be moved to a closed configuration in which the two plates substantially abut one another and an intervening portion of the continuous current collector is held between the two plates. In some embodiments, closing the plates can hold the intervening portion of the continuous current collector between the plates.

[0067] In some embodiments, in the third step, a masking material can be placed on the exposed portion of the continuous current collector to protect at least a portion of the current collector from receiving a coating of the semi-solid electrode slurry and define at least one edge of the current collector. In some embodiments, the edge of the current collector can be defined by limiting the area that can be coated with the semi-solid electrode slurry. In some embodiments, the masking material can be initially stored in a rolled state and can be dispensed onto the current collector by a masking material dispensing system.

[0068] In some embodiments, the masking material can be applied in a direction parallel to the direction of movement of the continuous current collector. In some embodiments, the masking material can be applied before a portion of the current collector is interposed between two plates. In other words, the masking material can be applied to the current collector, and then a portion of both the current collector and the masking material can be interposed between two plates. Interposition of an already masked current collector can cause damage or misalignment of the masking material, but it can also secure the masking material during deposition of the semi-solid electrode slurry onto the masked interposed current collector.

[0069] In some embodiments, the masking material can be applied to the continuous current collector after it is unwound from a feed reel or similar device and before the semi-solid electrode slurry is disposed on the current collector. The coating may be applied to a continuous current collector before being wound onto a reel or similar device.

[0070] In some embodiments, in the fourth step, the semi-solid electrode slurry can be disposed on the masked, partially interposed continuous current collector by a dispensing mechanism. In some embodiments, the disposed semi-solid electrode slurry can be disposed on the continuous current collector without being disposed on the interposed portion of the continuous current collector. In some embodiments, some of the semi-solid electrode slurry material disposed on the current collector can also be disposed on the masking material. In some embodiments, the abutting of the plates can help reduce or eliminate loss of semi-solid electrode slurry to the portion of the continuous current collector interposed between the two plates.

[0071] In some embodiments, in the fifth step, the masking material can be removed from the current collector surface before moving the two plates to the open configuration. The removed masking material can be connected to a masking material recovery system. In some embodiments, the masking material recovery system can include a subsystem for cleaning any accumulated semi-solid electrode slurry from the masking material. In some embodiments, the masking material can be removed from the current collector surface after moving the two plates to the open configuration. In some embodiments, the masking material can be a closed-loop system so that the masking material can be used, cleaned, and then reused in the same manufacturing process. In other words, the masking material can be cleaned, returned to the beginning of the electrode manufacturing process, and applied to the current collector. In some embodiments, a more durable masking material can be used so that the lifespan of the masking material makes its use cost-effective.

[0072] In some embodiments, in the sixth step, the plates can be opened to expose intervening portions of the continuous current collector. In some embodiments, opening the plates can also separate distinct portions of the semi-solid electrode slurry on the continuous current collector. In some embodiments, the plates can be opened by mechanical action on the plates. In some embodiments, the plates can be at least partially opened by accelerating the conveying speed of the continuous current collector. In some embodiments, as shown in FIG. 6B, the distinct portions of the semi-solid electrode slurry can be configured to have well-structured (i.e., clean or straight) lines on two or more sides of the distinct portions of the semi-solid electrode slurry. In some embodiments, each distinct portion of the semi-solid electrode slurry on the current collector can be considered an electrode of an electrochemical cell.

[0073] Continuous Method 9-11 illustrate a method of continuously manufacturing a semi-solid electrode by covering or otherwise protecting a portion of a continuous current collector from being coated with the semi-solid electrode slurry. In some embodiments, the continuous current collector can be protected by prior application of a masking material. In some embodiments, the masking material can be applied onto the continuous current collector before it is loaded into a current collector feeder configured to feed the current collector to a conveyor, e.g., a reel feeder.

[0074] In some embodiments, the mask material can be printed onto the current collector so that it is permanently disposed on the current collector. In some embodiments, the mask material can be printed onto the current collector during its manufacture.

[0075] In some embodiments, the masking material is applied to the continuous current collector after it is unwound from the current collector feeder and before the semi-solid electrode slurry is placed on the masked current collector. can be done.

[0076] In some embodiments, the masking material can include any suitable material configured to removably adhere to the current collector over the range of temperatures and conditions experienced during manufacturing. In some embodiments, the masking material can be made from a polymer, a cross-linking agent, a thermoplastic polymer, a polyimide, a nonwoven synthetic material, an extruded thermoformed material, paper, metal, natural fiber, or a combination thereof. In some embodiments, the masking material can include an adhesive, such as a rubber-based adhesive, an acrylic-based adhesive, or a silicone-based adhesive.

[0077] In some embodiments, the masking material can be applied in a direction parallel and / or perpendicular to the direction of travel of the continuous current collector. In some embodiments, the perpendicularly applied masking material can be applied separately from the parallelly applied masking material. In some embodiments, the masking material can include a web structure such that both the parallel and perpendicular masking materials are included in one material and applied simultaneously.

[0078] In some embodiments, the manufacturing process can be substantially completely continuous, at least in part because the plates do not need to be moved between open and closed configurations. In some embodiments, a conveyor system can be used to pass the masked current collector through a distribution mechanism, such as a slurry casting station. Without wishing to be bound by any particular theory, because the current collector is at least partially masked, the slurry casting speed can be substantially increased, at least to some extent, without the tradeoff of less precise, crumbling electrode edges.

[0079] In some embodiments, the semi-solid electrode slurry can be applied to the masked current collector using a designed nozzle configured to precisely distribute the slurry onto the current collector. In some embodiments, the deposition of the semi-solid electrode slurry here can be substantially similar to the method described above with respect to FIG.

[0080] In some embodiments, once the semi-solid electrode slurry is disposed on the masked current collector, the manufacturing process can include an optional slurry spreading step. In some embodiments, the slurry spreading can be performed using a roller or a series of rollers. In some embodiments, a doctor blade or other similar device can be used to remove excess slurry material from the masked current collector.

[0081] In some embodiments, once the slurry is spread substantially uniformly on the current collector, the surface speed of the current collector along the conveyor can be increased to form a small gap between the formed electrodes. In some embodiments, the gap formed between the formed electrodes can be between about 100 μm and about 15 mm, between about 250 μm and about 10 mm, between about 500 μm and about 9 mm, between about 750 μm and about 8 mm, between about 1 mm and about 7 mm, between about 2 mm and about 6 mm, or between about 3 mm and about 5 mm, including all values ​​and ranges therebetween. In some embodiments, the gap formed between the formed electrodes can be greater than about 100 μm, 250 μm, 500 μm, 750 μm, 1 mm, 2 mm, 3 mm, 4 mm, 5 mm, 6 mm, 7 mm, 8 mm, 9 mm, 10 mm, or 15 mm, including all values ​​and ranges therebetween.

[0082] In some embodiments, the formed electrode can be polished by passing the formed electrode between two or more rollers to compress the formed electrode and, if necessary, heat it. In some embodiments, the formed electrode can be polished by, for example, about 1 g / The electrode can be glazed to a particular density of greater than about 4 g / cm, 1.5 g / cm, 1.75 g / cm, 2 g / cm, 2.25 g / cm, 2.5 g / cm, 2.75 g / cm, 3 g / cm, 3.25 g / cm, 3.5 g / cm, 3.75 g / cm, or about 4 g / cm, including all values ​​and ranges therebetween. While not wishing to be bound by any particular theory, glazing the electrode can result in a desired reduction in porosity (increased energy density), a more uniform thickness in the z-direction, and / or a reduction in contact resistance at the current collector-electrode interface, among other results.

[0083] In some embodiments, the polishing process can result in a semi-solid electrode having a porosity of less than about 99%, about 95%, 90%, 85%, 80%, 75%, 70%, 65%, 60%, 55%, or less than about 50% of the porosity of the unpolished semi-solid electrode, including all values ​​and ranges therebetween. In some embodiments, a reduction in porosity to less than about 60% of the porosity of the unpolished semi-solid electrode can result in cracks or other defects in the semi-solid electrode and / or current collector.

[0084] In some embodiments, the polishing process can result in a semi-solid electrode having a raw porosity of less than about 50%, 45%, 40%, 35%, 30%, 25%, 20%, 19%, 18%, 17%, 16%, 15%, 14%, 13%, 12%, 11%, 10%, 9%, 8%, 7%, 6%, or about 5%, including all values ​​and ranges therebetween.

[0085] In some embodiments, after burnishing, the finished electrode comprising the current collector and semi-solid electrode slurry can have a z-direction thickness of less than about 2000 μm, less than about 1,500 μm, less than about 1,000 μm, less than about 750 μm, less than about 500 μm, less than about 250 μm, less than about 200 μm, less than about 150 μm, less than about 100 μm, less than about 75 μm, less than about 50 μm, or less than about 25 μm, including all values ​​and ranges therebetween. In some embodiments, the finished electrode comprising the current collector and semi-solid electrode slurry can have a z-direction thickness of between about 25 μm and about 2000 μm, about 25 μm and about 1,500 μm, about 50 μm and about 1,000 μm, about 75 μm and about 750 μm, or about 100 μm and about 500 μm, including all values ​​and ranges therebetween.

[0086] In some embodiments, the mask material can be removed from the continuous current collector after the formed electrode has been polished as needed. In some embodiments, the mask material can be connected to a mask material recovery system, which is configured to force the removal of the mask material from the continuous current collector. In some embodiments, the removal of the mask material from the continuous current collector can be performed in a controlled manner so that the mask material does not remove the semi-solid electrode slurry from the formed electrode. In some embodiments, the mask material recovery system can include a subsystem for washing any accumulated semi-solid electrode slurry from the mask material.

[0087] In some embodiments, removal of the masking material can form a gap between each formed electrode. In some embodiments, the gap formed between each formed electrode can be sufficient to allow clean separation of each individual formed electrode on the continuous current collector. In some embodiments, the gap formed between each formed electrode can be sufficient to allow cutting of the continuous current collector to form individual electrodes.

[0088] In some embodiments, the current collector can be cut perpendicular to the direction of travel of the current collector between each separate portion of the semi-solid electrode slurry to form individual electrodes. In some embodiments, the current collector can be cut using a laser (e.g., CO gas laser, high-power diode laser, fiber optic laser, etc.), drilling, plasma cutting, using a reciprocating blade, pan cutting, etc. The electrodes can be cut using a tool or press, pneumatic cutting, hydraulic cutting, other methods known to those skilled in the art, or a combination thereof. In some embodiments, as shown in Figure 8, individual electrodes can be picked up from a conveyor (e.g., using a robotic arm) and placed on a different conveyor. In some embodiments, if the gaps formed between each formed electrode after cutting the continuous current collector are insufficient, the speed of the conveyor can be increased beyond a certain point to create more space between adjacent formed electrodes.

[0089] In some embodiments, if the completed electrode is not already bonded to the pouch material, the individual electrodes can be bonded to the pouch material in this step. In some embodiments, the individual electrodes can be bonded to the pouch material by heating at least a portion of the pouch material to fuse the pouch material to the current collector. In some embodiments, an adhesive can be used to adhere the pouch material to the current collector.

[0090] In some embodiments, individual electrodes may be polished as needed to reduce the thickness of the semi-solid electrode slurry on the current collector and / or reduce defects. In some embodiments, a beta gauge, such as a moving web thickness and / or weight measurement system, may be used to ensure proper and consistent z-direction thickness of the semi-solid electrode slurry on the current collector. In some embodiments, a video camera and computer processor may be used to visually inspect the finished electrodes and discard any defective electrodes, for example, using a computer vision program.

[0091] In some embodiments, the semi-solid electrode slurry can be placed on a current collector in a roll casting system, for example, as shown in FIG. 11 . In some embodiments, the roll casting system can include a vacuum pallet or vacuum conveyor system configured to transport the current collector through the manufacturing system. In some embodiments, the anode can be manufactured in an anode conveyor system, and the cathode can be manufactured in a cathode conveyor system. In some embodiments, the anode conveyor system and the conveyor system can be positioned opposite each other so that the conveyors deliver completed anodes near the completed cathodes to facilitate assembly of the electrochemical cell. In some embodiments, a separator roll feeder can deliver a constant or intermittent supply of separator material between each anode and the corresponding cathode. In some embodiments, the separator can be interposed between the cathode and anode after the mask material is removed and before or after the completed electrodes are formed by cutting the current collectors.

[0092] In some embodiments, once the mask material is removed, the conveyor system can be configured to transport the current collector past a beta gauge to determine the thickness of the semi-solid electrode slurry on the current collector. In some embodiments, if the finished electrode is thicker than desired, the electrode can be polished (before or after removing the mask material) to reduce the thickness and / or densify the semi-solid electrode material and / or remove the electrolyte.

[0093] In some embodiments, the roll casting system can be configured to continuously form cathodes and continuously form electrodes with separators interposed therebetween. In some embodiments, the roll casting system can continuously form finished electrodes by sealing separate portions of semi-solid electrode material between portions of pouch material and cutting the pouch material to form individual pouch cells.

[0094] End Frame In some embodiments, a continuous or semi-continuous process for producing a semi-solid electrode comprises: This can include the use of an end frame structure. In some embodiments, instead of or in addition to a masking material, an end frame structure can be placed on the current collector before disposing the semi-solid electrode slurry on the current collector, as described above. In some embodiments, the end frame can hold the current collector in place. In some embodiments, the end frame can have at least some z-direction thickness such that the end frame at least partially defines a cavity in which the semi-solid electrode slurry can be placed and held on the surface of the current collector.

[0095] In some embodiments, the end frame can at least partially define the surface area of ​​the finished electrode (e.g., as the interior extent of the end frame). In some embodiments, the end frame can at least partially define the thickness of the semi-solid electrode slurry on the current collector based on the height of the end frame in the z-direction. In some embodiments, the semi-solid electrode slurry can be smoothed or spread along the surface of the exposed portion of the current collector. In some embodiments, a blade (also referred to herein as a "doctor blade") or other straight-edge device can be used to spread the semi-solid electrode slurry. In some embodiments, the blade and / or end frame can be operably coupled to a vibration source to vibrate the blade or end frame during deposition or smoothing of the semi-solid electrode slurry. The vibration can facilitate distribution of the semi-solid electrode slurry material during or after the slurry deposition step.

[0096] In some embodiments, the instrument is an optical or any analytical tool that uses any of the non-contact measurement techniques including, for example, optical or laser interferometry, ellipsometry, or optical or laser scanning probes to inspect the surface morphology of the spread semi-solid electrode slurry and optionally measure the surface uniformity (e.g., thickness). In some embodiments, the non-contact instrument can be deployed in situ as the blade spreads the semi-solid electrode slurry.

[0097] In some embodiments, after the semi-solid electrode slurry is spread, the end frames can be removed, leaving only the portion of the semi-solid electrode slurry spread on the exposed portion of the current collector. Alternatively, in some embodiments, after the semi-solid electrode slurry is spread, the end frames can remain in place and a separator can be placed over the completed electrode such that the separator, current collector, and end frames each partially define an electroactive zone to contain the semi-solid electrode slurry within the electroactive zone.

[0098] In some embodiments, a masking material can be used in addition to the end frame to prevent contamination of uncoated portions of the current collector and / or exposed portions of the pouch material. In some embodiments, the end frame can be first placed on the current collector, followed by application of a masking material to protect and / or define one, two, three, or four of the edges of the finished electrode. In some embodiments, the masking can extend to or beyond the edges of the current collector material. In some embodiments, the masking material and the end frame can initially be an integral part of a single placed material, which is configured so that the masking can be removed while the end frame remains placed on the current collector. In some embodiments, the single placed material, including the end frame and masking material, can be substantially completely removed from the current collector after the semi-solid electrode slurry is placed on the current collector.

[0099] In some embodiments, the end frames can extend to the edges of the current collector material so that the semi-solid electrode slurry can be more quickly and carefully placed onto the continuous current collector. Similarly, in some embodiments, each end frame can extend to the edges of the semi-solid electrode material. The slurry can be positioned and configured to directly and securely abut at least one other end frame, preventing placement of a continuous current collector or pouch material between two or more end frames. In some embodiments, after the semi-solid electrode slurry is placed on the current collector, vibration or other suitable methods can be used to remove any semi-solid electrode slurry that has accumulated on the end frame structure.

[0100] In some embodiments, the end frame and / or masking material can be configured to naturally repel the semi-solid electrode slurry to some extent based on chemical, electrochemical, physical structure, or other properties. In some embodiments, the end frame and / or masking material can be made of a material that forms a small contact angle with the semi-solid electrode slurry. In some embodiments, the end frame and / or masking material used when fabricating the anode can be different from the end frame and / or masking material used when fabricating the cathode due to chemical differences between the anode and cathode semi-solid electrode slurries.

[0101] Continuous with doctor blade 12A-12C illustrate various steps in a process for fabricating an electrochemical cell having at least one of an anode and a cathode comprising a semi-solid electrode slurry. As shown in FIG. 12A, in step 1, a masking material can be placed over a portion of a conductive material that can be used as a current collector for the electrochemical cell. In some embodiments, the masking material can be placed over the conductive material such that only the exposed portion of the conductive material visible through the masking is available for deposition of the semi-solid electrode slurry. In some embodiments, the conductive material can include a protruding piece of conductive material that can be a power connection tab.

[0102] As shown in FIG. 12B, in step 2, the semi-solid electrode slurry can be placed on the exposed portion of the conductive material. In steps 3 and 4, the electrode can be smoothed or spread along the surface of the exposed portion of the second layer. For example, a blade or straight edge tool can be used to spread the electrode. In step 5, the masking can be removed, leaving only the portion of the electrode that was spread on the exposed portion of the conductive material. As shown in FIG. 12C, in step 6, a separator can be placed on a portion of the current collector so that the separator covers the electrode. In step 7, the completed semi-solid electrode and separator from step 6 can be joined with another electrode. For example, the electrode from step 6 can be a cathode electrode, and the other electrode can include an anode electrode. In step 8, a vacuum and heat sealing process can be performed to seal the two laminate sheets together to form a completed cell, as shown in step 9.

[0103] In some embodiments, after depositing the semi-solid electrode slurry, the completed cathode and anode can be stacked with a separator interposed therebetween. In some embodiments, the separator can be placed in a pouch material first, the cathode can be stacked on the separator, the separator can then be folded over the cathode, the anode can be stacked on the separator, and the separator can be folded back across the anode. In some embodiments, this process of folding the separator back and forth and stacking alternating anodes and cathodes can be carried out until the appropriate number of anodes and cathodes has been assembled accordingly. In some embodiments, the cathodes and anodes can be arranged according to a transverse or longitudinal plane and sealed to form by any of the heat-sealing methods described herein. In some embodiments, the resulting assembly can be folded in a zigzag pattern by the separator. Although the use of either stacking or zigzag folding has been described for continuous manufacturing processes using masking materials, any of the methods for handling finished electrodes, or any other suitable method, can be used with any of the methods and systems described herein.

[0104] While various embodiments have been described above, it should be understood that they have been presented by way of example only, and not by way of limitation. While the above-described schematic diagrams and / or embodiments show particular components arranged in particular orientations or positions, the arrangement of the components can be changed. While embodiments have been particularly shown and described, it will be understood that various changes in form and detail can be made. While various embodiments have been described as having particular features and / or combinations of components, other embodiments are possible having any combination of features and / or components from any of the embodiments described herein.

[0105] The specific configuration of the various components may also be varied. For example, the size and specific shape of the various components may differ from the illustrated embodiment while still providing the functionality described herein. More specifically, the size and shape of the various components may be specifically selected for a desired or intended use. Thus, it should be understood that the size, shape, and / or arrangement of an embodiment and / or its components may be adapted for a given application unless the context clearly dictates otherwise.

[0106] Where the methods and / or events described above indicate that certain events and / or steps occur in a particular order, the order of the certain events and / or steps may be changed. Furthermore, certain events and / or steps may be performed simultaneously in parallel processes where possible, or may be performed sequentially as described above.

Claims

1. continuously dispensing the semi-solid electrode slurry onto a current collector; separating the semi-solid electrode slurry into separate portions; and cutting the current collector to form a finished electrode.

2. moreover, 10. The method of claim 1, comprising adjoining the completed electrode with a second completed electrode sandwiched by a separator to form a completed electrochemical cell.

3. The method of claim 1 , wherein the semi-solid electrode slurry is binder-free.

4. The method of claim 1 , wherein the semi-solid electrode slurry is dispensed via a stationary dispensing mechanism.

5. 5. The method of claim 4, wherein the current collector moves past the stationary distribution mechanism at a speed greater than about 1 meter per minute.

6. 5. The method of claim 4, wherein the stationary distribution mechanism includes a nozzle configured to distribute the semi-solid electrode slurry to multiple regions of the current collector at a predetermined velocity as the current collector passes by the stationary distribution mechanism.

7. The method of claim 1 , wherein the semi-solid electrode slurry is dispensed via an adjustable dispensing mechanism.

8. The method of claim 7 , wherein the adjustable dispensing mechanism is a nozzle configured to move along a z-axis.

9. The method of claim 8 , wherein the nozzle controls the casting gap to an accuracy of less than 1 μm.

10. 1. A method for manufacturing a semi-solid electrode, comprising: interposing a portion of the current collector material between the first plate and the second plate to form a distribution surface; continuously distributing a semi-solid electrode slurry onto said distribution surface; removing a portion of the current collector material from between the two plates to separate the semi-solid electrode slurry into separate portions; and cutting the current collector to form the semi-solid electrode.

11. The method of claim 10, wherein the semi-solid electrode slurry is binder-free.

12. The method of claim 10 , wherein interposing the portion of the current collector material between the first plate and the second plate is performed by a forcing device.

13. 11. The method of claim 10, wherein the first plate has a first fixed edge and the second plate has a second fixed edge, the first fixed edge abutting the second fixed edge to frictionally engage a portion of the current collector.

14. moreover, 11. The method of claim 10, comprising adjoining the completed electrode with a second completed electrode interposed by a separator to form a completed electrochemical cell.

15. moreover, 11. The method of claim 10, comprising inspecting the completed electrode via a video camera and computer processor.

16. 1. A method for manufacturing a semi-solid electrode, comprising: continuously disposing a mask material on a current collector material; continuously dispensing a semi-solid electrode slurry onto the current collector material; removing the mask material to at least partially define discrete portions of semi-solid electrode slurry on the current collector; and cutting the current collector to form the semi-solid electrode.

17. 17. The method of claim 16, wherein the semi-solid electrode slurry is binder-free.

18. moreover, 17. The method of claim 16, comprising spreading the semi-solid electrode slurry with a blade.

19. moreover, 20. The method of claim 18, wherein the blade vibrates during spreading of the semi-solid electrode slurry.

20. moreover, 17. The method of claim 16, comprising adjoining the semi-solid electrode with a second electrode sandwiched by a separator to form a completed electrochemical cell.

Images