Continuous and semi-continuous method for manufacturing semi-solid electrodes and batteries

Abstract

The present disclosure relates to continuous and semi-continuous methods of manufacturing semi-solid electrodes and batteries. Embodiments described herein generally relate to systems and methods for continuous and / or semi-continuous fabrication of semi-solid electrodes and batteries incorporating the semi-solid electrodes. In some embodiments, a process of fabricating 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 fabricated electrode.

Description

[0001] This application is a divisional application of the invention application with an application date of July 9, 2019, an international application number of PCT / US2019 / 041061, an entry date of the Chinese national phase of December 15, 2020, an application number of 201980039898.4, and an invention name of “Continuous and semi-continuous methods for the manufacture of semi-solid electrodes and batteries”.

[0002] CROSS-REFERENCE TO RELATED APPLICATIONS

[0003] This application claims priority to and the benefit of U.S. Provisional Patent Application No. 62 / 695,483, filed on 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. Technical Field

[0004]

[0013] 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 Art

[0005] The battery manufacturing method generally includes coating a conductive substrate (i.e., a current collector) with a slurry, which includes an active material, a conductive additive, and a binding agent dissolved or dispersed in a solvent. After the slurry is applied to the metal substrate, the slurry is dried (e.g., by evaporating the solvent) and rolled to a specified thickness. The manufacture of battery electrodes may also generally include material mixing, casting, rolling, drying, slitting, and processing (bending, rolling, etc.) according to the battery architecture to be constructed. Because the electrodes are manipulated during assembly, and in order to ensure that the conductive network is in place, all components are compressed into a cohesive assembly, for example, by using a binding agent. However, the binding agent itself takes up space, increases processing complexity, and hinders ionic and electronic conductivity. Therefore, there is a need for improvements in the manufacture of electrochemical cells (e.g., batteries) and electrochemical cells, such as eliminating components of electrochemical cells and / or providing reduced packaging of electrochemical cells while maintaining the same energy storage capacity. Summary of the invention

[0006] 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. In some embodiments, the process of manufacturing the semi-solid electrode includes continuously dispensing the 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. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] Figure 1 Steps of a process for manufacturing an electrode and optionally an electrochemical cell according to an embodiment are illustrated.

[0008] Figure 2 A dispensing mechanism according to an embodiment is illustrated.

[0009] Figure 3 A dispensing mechanism according to an embodiment is illustrated.

[0010] Figure 4 A dispensing mechanism according to an embodiment is illustrated.

[0011] Figure 5 A process for manufacturing an electrode according to an embodiment is illustrated.

[0012] Fig. 6A is a photograph of a semi-solid electrode slurry deposited on a moving current collector, part of which is tucked between two plates, according to an embodiment.

[0013] Figure 6B According to an embodiment, after moving the two plates apart to expose the folded portion of the current collector Fig. 6A Photo of the current collector.

[0014] Figure 7 is a schematic diagram of a system for semi-continuous or continuous manufacturing of semi-solid electrodes according to an embodiment.

[0015] Figure 8 is a schematic diagram of a system for semi-continuous or continuous manufacturing of semi-solid electrodes according to an embodiment.

[0016] Fig. 9 is a schematic diagram of a system for semi-continuous or continuous manufacturing of semi-solid electrodes according to an embodiment.

[0017] Fig.10 is a schematic diagram of a system for semi-continuous or continuous manufacturing of semi-solid electrodes according to an embodiment.

[0018] Fig.11 is a schematic diagram of a system for semi-continuous or continuous manufacturing of semi-solid electrodes according to an embodiment.

[0019] Figure 12A-12CSteps of a process for manufacturing an electrochemical cell according to an embodiment are illustrated. DETAILED DESCRIPTION

[0020] Embodiments described herein generally relate to systems and methods for continuously and / or semi-continuously manufacturing semisolid electrodes and batteries incorporating semisolid electrodes. Embodiments described herein generally relate to methods for manufacturing semisolid electrodes, the method comprising disposing a semisolid electrode material onto a current collector. In some embodiments, the method may include continuously dispensing a semisolid electrode slurry onto a current collector, separating the semisolid electrode slurry into discrete portions, and cutting the current collector to form a manufactured electrode.

[0021] Conventional electrodes and conventional electrochemical cells are typically prepared by coating discrete portions of a metal foil substrate with a thin (e.g., about 10 μm to about 200 μm) wet slurry that is subsequently dried and calendered to a desired thickness. The slurry components in this process are typically active material, conductive additive, binder, and solvent (e.g., typically N-methylpyrrolidone (NMP)). When the solvent evaporates (in a drying oven covering the conveyor line), the binder is converted into a "glue" that holds all the solid particles together in a matrix that is bonded to the substrate. Electrodes are typically coated with the same material on both sides of the substrate.

[0022] There are two common battery design approaches, (1) winding and (2) stacking. In a wound battery design, the electrode sheets may be cut to a target size and then wound into a spiral or jelly roll with a separator placed in the middle, then infiltrated with electrolyte and appropriately packaged (usually in a cylindrical or rectangular metal can) to provide containment and electrical connections. In a stacked battery design, the electrode sheets may also be cut to a target size, but then stacked one on top of the other with a separator placed in the middle. Thus, a stacked battery consists of physically discrete electrode sheets, rather than continuous electrodes (i.e., in anode / cathode pairs) as in the case of a wound battery. The stacked assembly may then be infiltrated with electrolyte and typically packaged in either a pouch / bag, a plastic box, or a metal can (which may also each be referred to as a battery or battery housing as described herein).

[0023] In conventional bag packaging, the bag can perform several functions. One such function is to provide an airtight isolation of the battery materials from the environment. Thus, the bag can be used to prevent harmful materials (such as electrolyte solvents and / or corrosive salts) from leaking into the surrounding environment, and can prevent water and / or oxygen from penetrating into the battery. Other functions of the bag can include, for example, compression packaging of the inner layer, voltage isolation for safety and handling, and mechanical protection of the battery components.

[0024] Typical bag materials may include a laminate (e.g., a multilayer sheet) formed, for example, as two or three solid film-like layers, and bonded together by an adhesive. As used herein, the word "laminate" may also refer to layers of material that are not chemically adhered to each other. For example, the layers may be in areal contact with each other and coupled using other coupling methods, such as, for example, heat sealing. The inner layer may be, for example, a plastic layer, such as, for example, cast polypropylene (CPP). The next or second layer may be a metal foil layer, such as, for example, aluminum or an aluminum alloy. In some bag constructions, there may be (one or more) additional layers. The additional layer may, for example, be a protective coating formed with, for example, a plastic, such as nylon. The metal foil may provide a sealing function, which is much less permeable to certain compounds, especially water, than plastic. The plastic inner layer may be heat-bonded to itself, which is a convention for bag closure and allowing electrical passage. In bag closure, if the inner layers (e.g., CPP) of two bag laminates are brought into physical contact and heat is applied, the layers will melt and fuse, creating a secure seal if the processing conditions (e.g., power, temperature, duration) are appropriately selected. For example, when sealed in a closed loop, an internal volume isolated from the surrounding or external environment can be formed.

[0025] Some known electrochemical cells (e.g., batteries) can include a variety of shapes and / or sizes, can be based on a variety of enabling materials and internal architectures, can be either passively or actively controlled, can be rechargeable or not rechargeable, and / or can share certain common features that allow them to convert chemical energy into electrical energy. Some known batteries can include a first electrode having a high electrochemical potential and a second electrode having a low electrochemical potential relative to the first electrode. Each electrode can include an active material that participates in a chemical reaction and / or a physicochemical transformation during discharge due to a favorable thermodynamic change in the state of the material, which causes current to flow when the switch is closed. In some cases, two different conductive networks can allow the anode and cathode to be electrically connected in order for charge transfer to occur. A separator can be used to provide isolation of the anode and cathode so that only ions can pass and prevent short circuits.

[0026] The manufacture of battery electrodes can be a complex and capital-intensive process, and can often include material mixing, casting, calendaring, drying, slitting, and processing (bending, rolling, etc.), depending on the battery architecture being built. Because the electrodes are manipulated during assembly, and to ensure that the conductive network is in place, all components are compressed into a cohesive assembly, for example, by using a binder. However, the binder itself takes up space, increases processing complexity, and can hinder ionic and electronic conductivity.

[0027] As used in this specification, the singular forms "a", "an", and "the" include plural referents unless the context clearly dictates otherwise. Thus, for example, the term "a member" is intended to mean a single member or a combination of members, and "a material" is intended to mean one or more materials or a combination thereof.

[0028] The term "substantially" when used in connection with "cylindrical," "linear," and / or other geometric relationships is intended to convey a structure that is defined as being 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 desirable, some nonlinearity may occur in the "substantially linear" portion. Such nonlinearity may be due to manufacturing tolerances or other practical considerations (such as, for example, pressure or forces applied to the support member). Thus, a geometric configuration modified by the term "substantially" includes such geometric properties within a tolerance of plus or minus 5% of the geometric configuration. For example, a "substantially linear" portion is a portion of an axis or centerline that is defined to be within plus or minus 5% of linearity.

[0029] As used herein, the terms "set" and "plurality" can refer to multiple features or a single feature with multiple parts. For example, when referring to a set of electrodes, the set of electrodes can be considered to be one electrode with multiple parts, or the set of electrodes can be considered to be multiple distinct electrodes. In addition, for example, when referring to multiple electrochemical cells, the multiple electrochemical cells can be considered to be multiple distinct electrochemical cells or one electrochemical cell with multiple parts. Therefore, a set of parts or multiple parts can include multiple parts that are either continuous or discontinuous with each other. Multiple particles or multiple materials can also be made of multiple items that are produced separately and later joined together (e.g., via mixing, adhesives, or any suitable method).

[0030] As used herein, the term "z-direction" generally refers to a third direction, where the longitudinal and transverse directions are the first and second directions. In other words, the z-direction refers to the depth or thickness of a feature as opposed to the length and width.

[0031] As used herein, the terms "about" and "approximately" generally refer to plus or minus 10% of the stated value, for example, approximately 250 μm would include 225 μm to 275 μm, and approximately 1,000 μm would include 900 μm to 1,100 μm.

[0032] As used herein, the term "semisolid" refers to a material that is a mixture of a liquid phase and a solid phase, such as, for example, a particulate suspension, a colloidal suspension, an emulsion, a gel, or a micelle.

[0033] As used herein, the terms "activated carbon network" and "networked carbon" refer to the general qualitative state of an electrode. For example, an electrode having an activated carbon network (or networked carbon) causes the carbon particles within the electrode to take individual particle forms and arrangements relative to each other, which promotes electrical contact and conductivity between the particles. In contrast, the terms "unactivated carbon network" and "unnetworked carbon" refer to an electrode in which the carbon particles exist as either individual particle islands or multi-particle agglomerated islands that may not be sufficiently connected to provide sufficient conduction through the electrode.

[0034] Figure 1 A schematic diagram of a method 10 for manufacturing a semi-solid electrode in a continuous or semi-continuous manner is shown. In some embodiments, the method 10 includes continuously dispensing the semi-solid electrode slurry onto a collector 11 as the semi-solid electrode slurry passes through a delivery system. In some embodiments, the delivery system can be configured to continuously or semi-continuously transport the collector through a fixed dispensing mechanism. In some embodiments, the dispensing mechanism can be adjustable and / or movable relative to the collector. In some embodiments, the fixed dispensing mechanism can be a nozzle that is configured to dispense the semi-solid electrode slurry onto a specific area of ​​the collector at a predetermined and precise rate as the semi-solid electrode slurry passes through the fixed dispensing mechanism.

[0035] Distributing semi-solid slurry can generate a large amount of force on the conveying system. The force generated by distributing semi-solid slurry is proportional to the load of semi-solid slurry (that is, the higher the viscosity of semi-solid slurry load, the more force is generated on the conveying system). In some embodiments, the force acting on the conveying system can be greater than 2,000lbf, greater than 2,500lbf, greater than 3,000lbf or greater than 3,500lbf. No matter how thoroughly the system is designed to limit deflection, this force will cause mechanical deflection in the conveying system. These deviations will affect the casting gap between the distribution mechanism and the current collector, which affects the thickness of the electrode. In some embodiments, the deviation can reach 100μm during the movement of only 10mm of the current collector through the conveying system. In some embodiments, the adjustable distribution mechanism can move in a way that offsets these deviations. In other words, the adjustable distribution mechanism can move up and down (that is, along the z-axis) to compensate for the deviation caused by the force of the distributed slurry. In some embodiments, the distribution mechanism can move up and down (that is, in the z-direction) along the entire width of the electrode. In some embodiments, the dispensing mechanism can move up and down on the left side of the electrode in an inclined manner 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 on the right side of the electrode in an inclined manner so that the dispensing mechanism is lower on the right side of the electrode than on the left side of the electrode.

[0036] In some embodiments, the dispensing mechanism can be moved 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 be moved along the z-axis by a distance greater than about 1 μm, greater than about 5 μm, greater than about 10 μm, greater than about 20 μm, greater than about 30 μm, greater than about 40 μm, greater than about 50 μm, greater than about 60 μm, greater than about 70 μm, greater than about 80 μm, greater than about 90 μm, or greater than about 100 μm to ensure accuracy of electrode thickness. The dispensing mechanism can be adjusted very quickly to match the timing of the movement of the delivery system. In some embodiments, the offsetting movement of the distribution 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 the gap of 200 μm can be achieved with an accuracy of 1 μm. The casting gap can then be changed from 200 μm to 175 μm in 0.1 seconds, and the gap of 175 μm can be achieved with an accuracy of 1 μm. In some embodiments, the servo-controlled movement can control the movement of the distribution mechanism to control the casting gap to the desired level of accuracy. In some embodiments, the beta meter reading of the latest produced electrode can be used to determine the movement plan of the distribution 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 within the casting nozzle may be moved up and down to control the casting gap between the dispensing mechanism and the current collector. In some embodiments, the semi-solid electrode slurry may be configured to remain in a predetermined area once dispensed onto the current collector.

[0037] 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 active components, thereby enhancing the commercial appeal of batteries made with 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 that is usually occupied by a binder in a conventional electrode can now be occupied by the following parts: 1) electrolyte, which has the effect of reducing tortuosity and increasing the total salt available for ion diffusion, thereby offsetting the typical salt consumption effect of thick conventional electrodes when used at high rates, 2) active materials, which have the effect of increasing the charge capacity of the battery, or 3) conductive additives, which have the effect of increasing the electronic conductivity of the electrode, thereby offsetting the high internal impedance of thick conventional electrodes. Without wishing to be bound by any particular theory, the reduced tortuosity and higher electronic conductivity of the semi-solid electrodes described herein lead to excellent rate capabilities and charge capacity of electrochemical cells formed by semi-solid electrodes.

[0038] In some embodiments, the current collector is a conductive material band that has not yet been assigned to a discrete current collector. The current collector has a length defining a longitudinal axis and a width defined as a dimension perpendicular to the longitudinal axis. The current collector is configured to be transported along its longitudinal axis by a conveying system (i.e., a direction of travel). In some embodiments, the width of the current collector may be substantially similar to the desired width or height of the current collector to be used in the semi-solid electrode to be made. In some embodiments, the width of the current collector may 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 to be used in the semi-solid electrode to be made.

[0039] In some embodiments, the thickness of the current collector is between about 0.01 μm and about 100 μm, between about 100 nm and about 100 μm, between about 1 μm and about 95 μm, between about 1 μm and about 90 μm, between about 1 μm and about 85 μm, or between about 1 μm and about 80 μm, including all values ​​and ranges therebetween. In some embodiments, the thickness of the current collector is 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 18 μm, less than about 19 μm, less than about 18 ... About 16μm, less than about 15μm, less than about 14μm, less than about 13μm, less than about 12μm, less than about 11μm, less than about 10μm, less than about 9μm, less than about 8μm, less than about 7μm, less than about 6μm, less than about 5μm, less than about 5μm, less than about 4μm, less than about 3μm, less than about 2μm, less than about 1μm, less than about 900nm, less than about 750nm, less than about 500nm, or less than about 100nm, including all values ​​and ranges therebetween.

[0040] The current collector is electronically conductive and can be electrochemically inactive under the operating conditions of the battery. In some embodiments, the current collector material 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 current collector for the positive electrode. In some embodiments, copper is used as the current collector for the negative electrode. In other embodiments, aluminum is used as the current collector for the negative electrode.

[0041] Semi-solid electrode slurries can be electrochemically configured to be used in anodes and / or cathodes. Semi-solid electrode slurries can include active materials in liquid electrolytes. In some embodiments, active materials that can be organic or inorganic can include but are 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) active materials (i.e., sources and sinks for ions and electrons), (2) carbon (or a mixture of carbons) or (one or more) other materials having the primary but not necessarily exclusive function of electronic conduction, and (3) electrolytes having the primary but not necessarily exclusive function of ion conduction (e.g., a solvent or a solvent mixture plus (one or more) salts). The electrode formulation can optionally include other additives having specific intended chemical, mechanical, electrical and / or thermal functions. The electrode formulation may include active materials, components and / or semisolid suspensions described, for example, 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 which are each hereby incorporated by reference.

[0042] In some embodiments, the semi-solid electrode slurry may include conductive additives, stabilizing additives, and / or gelling agents. Examples of semi-solid electrode slurries may 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.

[0043] In some embodiments, electrodes and electrochemical cells made directly from semi-solid electrode slurries avoid the use of conventional binders and conventional electrode casting steps in general. The use of semi-solid electrode slurries can also eliminate the need to inject electrolytes into electrode materials because the semi-solid electrode slurries already include electrolytes. Some benefits of this method include, for example: (i) a simplified manufacturing process with less equipment (i.e., less capital intensive), (ii) the ability to manufacture electrodes with different thicknesses and shapes (e.g., by changing the extrusion die size or other process conditions), (iii) the processing of thicker (>100 μm) and higher surface charge capacity (mAh / cm2) electrodes, thereby reducing the volume, mass and cost contribution of inactive components relative to active materials, and (iv) the elimination of binders, thereby reducing tortuosity and increasing the ionic conductivity of the electrode.

[0044] In some embodiments, the current collector can move through the distribution mechanism at a rate 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 rate at which the collector moves past a fixed distribution 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.

[0045] In some embodiments, the collector can be transported through the distribution mechanism using a belt, a vacuum tray, a vacuum conveyor, a belt conveyor, a roller, a moving disk, a pneumatic conveyor, a hydraulic conveyor, a vibrating conveyor, a vertical conveyor, a screw conveyor, by pulling or pushing the collector through a surface with a low coefficient of friction, any other suitable equipment or method, or a combination thereof. In some embodiments, the collector can be thin and highly deformable, so care should be taken not to wrinkle, fold, tear, bend, dent, or otherwise mishandle the collector during transportation. In some embodiments, to help protect the collector from such damage, the collector can be deployed on a bag material before the semi-solid electrode slurry is deployed on the collector (e.g., step 11). In some embodiments, deploying the collector on a bag material before the semi-solid electrode slurry is deployed on the collector can also help transport the collector through the distribution mechanism.

[0046] The method 10 also includes separating the semi-solid electrode slurry into discrete portions on the current collector 12. In some embodiments, the semi-solid electrode slurry can be separated into discrete portions on the current collector 12 by removing portions of the continuously deposited semi-solid electrode slurry. In some embodiments, the semi-solid electrode slurry can be separated into discrete portions on the current collector 12 by making portions of the current collector temporarily unavailable for receiving the deposited semi-solid electrode slurry thereon. In some embodiments, the semi-solid electrode slurry can be separated into discrete portions on the current collector 12 by changing the length of the current collector relative to the length of the continuously deposited semi-solid electrode slurry. In some embodiments, once the semi-solid electrode slurry has been deposited, the semi-solid electrode slurry can be separated into discrete portions on the current collector 12 by removing a previously deployed obstructive material from the current collector. In some embodiments, the discrete portions can be discrete electrodes produced by first deploying a masking material to at least a portion of the current collector, deploying the semi-solid electrode slurry onto the masked current collector, and then the masking material can be removed to define one or more fabricated electrodes.

[0047] In some embodiments, the semi-solid electrode slurry can be separated into discrete portions on the current collector 12 by any one of ultrasonic treatment, laser ablation, scraping, irradiation, high-precision cutting, or a combination thereof. In some embodiments, the semi-solid electrode slurry can be separated into discrete portions of the current collector 12 by accelerating the current collector at a certain distance through a dispensing mechanism, so that an uncoated portion of the current collector is formed between each discrete portion of the semi-solid electrode slurry.

[0048] In some embodiments, as discussed above, the width of the current collector (the dimension perpendicular to the direction of travel of the current collector through the delivery system) can be approximately equal to or greater than the width of the current collector to be used in the manufactured electrode. In some embodiments, the width of the current collector can accommodate the separation of the deployed semi-solid electrode slurry into more than one electrode portion in the width direction. In other words, in some embodiments, separating the semi-solid electrode slurry into discrete portions on the current collector 12 can include separating the semi-solid electrode slurry in two directions (parallel to the direction of travel of the current collector, and perpendicular to the direction of travel of the current collector).

[0049] Method 10 also includes cutting the current collector between discrete portions of the semi-solid electrode slurry to form a fabricated electrode 13. In some embodiments, the current collector can be cut by separating the defined segments of the current collector along the perforated range lines. In some embodiments, the current collector can be cut using a laser (e.g., a CO2 gas laser, a high-power diode laser, a fiber 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.

[0050] In some embodiments, each individualized current collector on which a discrete portion of a semi-solid electrode slurry is disposed can be considered a manufactured electrode. In some embodiments, the manufactured electrode can be deployed on an electrically insulating material (e.g., a laminated bag material) so that the current collector is directly adjacent to the insulating material. In some embodiments, an adhesive can be used to hold the manufactured electrode on the insulating material. In some embodiments, as described above, the current collector can be pre-deployed to an insulating material (e.g., a bag material) so that the individualization of the current collector material also includes cutting the insulating material to form a manufactured electrode.

[0051] In some embodiments, the electrode made may include an electrode tab that is electrically connected to the current collector and is configured to transport electrons into or out of the electrode. In some embodiments, the electrode tab may extend beyond the current collector and / or insulating material. In some embodiments, the electrode tab may be electrically coupled to the current collector before the semi-solid electrode slurry is deployed on the current collector. In some embodiments, the battery may include an integrated electrical tapping that eliminates the need for (i) discrete 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, an electrical tab or lead may be provided as part of a current collector that is integral with the current collector. In some embodiments, the tab or lead may be defined by removing material from a larger area of ​​the current collector material, thereby defining the current collector and the tab or lead.

[0052] Method 10 optionally includes coupling the fabricated electrode (e.g., cathode) to a second fabricated electrode (e.g., anode) with a separator interposed therebetween to form a fabricated electrochemical cell 14. In other words, once the fabricated electrodes have been individualized (e.g., according to step 13), they can be assembled into a fabricated electrochemical cell, wherein the second fabricated electrode exhibits an opposite redox reaction. In other words, the cathode and anode can be coupled together with a separator disposed therebetween.

[0053] In some embodiments, the separator may be disposed between the anode and the cathode. In some embodiments, the separator may be coupled to at least one of the anode and the cathode with an adhesive. In some embodiments, an anode, a cathode, and a separator may be stacked together to form a cell assembly. Each cell assembly may also include a conductive tab (also referred to as a lead) to couple the electrode to an external circuit. Multiple cell assemblies are then stacked or arranged together to form a battery cell. In some embodiments, the number of cell assemblies in a single cell may vary depending on, for example, the desired capacity and / or thickness of the resulting single cell. These stacked cell assemblies are electrically connected in parallel, and the corresponding tabs in each cell assembly are typically welded together via welding processes such as resistance welding, laser welding, ultrasonic welding, seam welding, electron beam welding, and the like.

[0054] In some embodiments, the prepared electrochemical cell can be vacuum sealed in a prismatic bag, which can provide an airtight isolation of the electrochemical cell material from the environment. Therefore, the bag can be used to avoid leakage of harmful materials (such as electrolyte solvents and / or corrosive salts) into the surrounding environment, and can prevent water and / or oxygen from penetrating into the battery. Other functions of the bag can include, for example, compression packaging of the inner layer, voltage isolation and processing for safety, and mechanical protection of the battery assembly. In some embodiments, during vacuum bag sealing, the electrolyte can be injected into the stacked unit cell assembly, and then the unit cell assembly and the electrolyte can be sealed into the bag. In some embodiments, if the semi-solid electrode slurry can already contain the entire desired amount of electrolyte, then no electrolyte is added during the bag sealing step.

[0055] In some embodiments, the sealed battery cell may then be subjected to a formation process, wherein an initial charging operation may be performed to produce a stable solid-electrolyte-interphase (SEI) that can passivate the electrode-electrolyte interface and prevent side reactions. In some embodiments, several cycles of charging and discharging may be performed to ensure that the capacity of the battery meets the required specifications. In some embodiments, a degassing step may be performed to release gases introduced or generated during the initial charging phase or during the electrochemical reaction in the battery formation step. The presence of trapped gases in the electrode generally reduces the conductivity and density of the electrode, limits the amount of active electrochemical material that can be placed in the battery cell, and causes dendrite growth that can erode the battery performance of the lithium battery. In some embodiments, dendrite formation results in a reduction in cycle life and a reduction in overall safety performance. In some embodiments, after releasing the trapped gas, a resealing step may be taken to seal the battery cell again.

[0056] In some embodiments, the methods described herein can be used to manufacture semi-solid electrodes and electrochemical cells in a shorter period of time than conventional electrochemical cell manufacturing methods. In some embodiments, the shorter period of time can minimize evaporation and / or degradation of the electrolyte, reduce manufacturing costs, and reduce the factory footprint required for the same electrochemical potential output.

[0057] Figure 2 A dispensing mechanism 100 according to an embodiment is shown, which can control the length of the casting gap T of the electrode. In some embodiments, the nozzle 110 can dispense the electrode slurry 120 onto the current collector 130 placed on the delivery system 140, and the casting gap T can be controlled by the movement of the nozzle blade 150. In some embodiments, the casting gap T can be controlled by the independent movement of the nozzle blade 150 relative to the nozzle 110, the current collector 130 and the delivery system 140 in the z direction. In some embodiments, the casting gap T can be controlled by the movement of both the nozzle 110 and the nozzle blade 150 relative to the current collector 130 and the delivery system 140 in the z direction.

[0058] Figure 3A distribution mechanism 200 is shown according to an embodiment that can control the length of the casting gap T between the nozzle 210 and the current collector 230 on the conveyor system 240. In some embodiments, the movement of the nozzle blade 250 in the z direction can be controlled by a collection of rollers 255. The rollers 255 can be pushed in from either side by a servo system (not shown), which can push the nozzle blade 250 down either on the left, right, 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 the entire width of the nozzle blade 250. In some embodiments, a collection of springs 259 may provide a force to return nozzle blade 250 to its original position after being lowered.

[0059] Figure 4 A distribution mechanism 300 is shown according to an embodiment, which can control the length of the casting gap T between the nozzle 310 and the current collector 330 on the conveying system 340. 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 cam shafts (not shown), which can rotate to push the nozzle blade 350 down either on the left side, on 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, so 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, so 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 the entire width of the nozzle blade 350. In some embodiments, a set of springs 359 can provide a force to return the nozzle blade to its original position after lowering.

[0060] Folding method

[0061] Figure 5-Figure 8A method for manufacturing a semi-solid electrode in a continuous or semi-continuous manner is illustrated. In some embodiments, the current collector material can be continuously moved from the current collector feeding device to the conveyor and pass through the distribution mechanism. In some embodiments, the current collector material can be continuously moved by the conveyor system. In some embodiments, the conveyor system may include a series of plates that are configured to move parallel to and / or perpendicular to the direction of travel of the conveyor. As used herein, a plate refers to a plurality of planar structures configured to move relative to the direction of travel of the conveyor system, and may also be a tray, sheet, cover, film or other suitable structure. In some embodiments, the conveyor system may include a shuttle conveyor, a steel belt conveyor, a belt conveyor, a perforated conveyor, a spreading conveyor, a roller conveyor, a chain conveyor or a combination thereof.

[0062] In some embodiments, a vacuum belt conveyor can be used to transport the current collector material through the manufacturing system. A vacuum belt conveyor generally includes a perforated belt and a sealed slide bed with a conveyor frame. In that way, air can be drawn out through the holes of the frame, thereby producing a partial vacuum. A vacuum belt conveyor can be used to transport lightweight and / or flat materials so that the material is held against the conveyor belt. A vacuum belt conveyor can be used to transport lightweight and / or flat materials at a higher speed, which can improve productivity. In some embodiments, a vacuum belt conveyor can be used to transport lightweight and / or flat materials in a non-horizontal direction (e.g., vertically).

[0063] In some embodiments, Fig. 6A and Figure 6B As shown in , portions of the continuous current collector can be inserted, folded, folded, gathered, wrinkled, doubly doubly, grouped, collected, hidden and / or otherwise excluded from deposition of electrode slurry material onto the continuous current collector. In other words, in some embodiments, one or more discrete portions of the continuous current collector can be isolated and excluded from receiving electrode slurry material.

[0064] In some embodiments, a portion of a continuous current collector can be moved in a direction perpendicular to the direction of travel of the continuous current collector. In some embodiments, after a portion of the current collector is moved away from the plane of travel (e.g., downward), the two edges of the inserted portion of the current collector can be moved together to completely isolate the inserted portion of the current collector.

[0065] In some embodiments, a continuous current collector can be moved across a series of adjacent plates, which are configured to open and close during continuous or semi-continuous manufacturing. In some embodiments, a plate can be configured to approximate the size of a manufactured electrochemical cell to minimize the waste of semi-solid electrode slurry materials. In some embodiments, a plate can be perforated or otherwise configured to be able to cross the surface of a plate to evacuate, so that the material can be kept on the surface regardless of the orientation of the plate. In some embodiments, a plate can be attached to a rotating system so that a plate can accommodate a current collector at one end of a conveyor line, convey the current collector during deposition of electrode material on the current collector, and then can be transferred back to the starting point of the conveyor line. In some embodiments, a plate can be cleaned or otherwise adjusted to reuse between the end of a conveyor line and the starting point of a conveyor line.

[0066] In some embodiments, a method of continuously or semi-continuously manufacturing a semi-solid electrode may include a first step in which a sheet may be initially opened while a continuous current collector is disposed on the sheet. Figure 7 and Figure 8 As shown in , a continuous current collector (i.e., foil) can be fed from a reel feeder across one or more rollers onto a conveyor. In some embodiments, the continuous current collector can be substantially the same as described above with respect to Figure 1 The continuous current collector described is similar.

[0067] In some embodiments, in the second step, a portion of the continuous current collector can be deployed (e.g., inserted or folded) between two open plates by any suitable method (including but not limited to extension rods, air knives, winding wires or any other suitable methods). In some embodiments, the continuous current collector can be slowed down, paused or stopped to facilitate the deployment of this portion of the continuous current collector between two open plates. In some embodiments, the continuous current collector can be moved constantly, and the deployment of this portion of the continuous current collector can be performed instantly (on-the-fly). In some embodiments, a flying folding device can be used, which can be configured to move at substantially the same speed as the continuous current collector while inserting this portion of the continuous current collector between the plates. In some embodiments, a fixed folding device can be used, which is configured to fold the portion of the continuous current collector between the plates when the continuous current collector moves through the fixed folding device. In some embodiments, a computer vision system can be configured to monitor the folding step and accurately control the movement of the folding device, the plate, and the timing of folding and loosening. In some embodiments, the computer vision system may be a closed-loop computer vision system including a camera, a processor, a memory, a power source, and a computer-readable medium configured to provide processing feedback to an automated manufacturing system.

[0068] In some embodiments, in the third step, the two open plates can be moved to a closed configuration in which the two plates are substantially adjacent to each other and the inserted portion of the continuous current collector is held between the two plates. In some embodiments, the closure of the plates can hold the inserted portion of the continuous current collector between the plates. In some embodiments, the plates can have a fastening edge so that the fastening edge of one plate can be directly adjacent to the fastening edge of an adjacent plate to frictionally engage the current collector. In some embodiments, the fastening edge can include a material that deforms to some extent when the plates are closed, which can increase the degree of fastening of the portion of the continuous current collector held between the plates in the third and fourth steps.

[0069] In some embodiments, in the fourth step, the semi-solid electrode slurry may be deployed onto a continuous current collector by a dispensing mechanism. Fig. 6A As shown in , the deployed semi-solid electrode slurry can be deployed onto the continuous current collector without being deployed onto the interposed portion of the continuous current collector. In some embodiments, the deformable fastening edge can help reduce or eliminate the loss of the semi-solid electrode slurry onto the interposed portion of the continuous current collector between the two plates.

[0070] In some embodiments, the dispensing mechanism can be a nozzle configured to dispense the semi-solid electrode slurry to a specific area of ​​the current collector at a predetermined and precise rate as the semi-solid electrode slurry passes through the dispensing mechanism. In some embodiments, the semi-solid electrode slurry can be configured to remain in a predetermined area once dispensed onto the current collector.

[0071] In some embodiments, Figure 7 As shown in , a parallel vertical tape casting / hybrid tape casting (VTC / HTC) station including parallel slurry boxes can be used to continuously or semi-continuously deploy the semi-solid electrode slurry onto the current collector. In some embodiments, as Figure 8 As shown in , a casting station can be used to continuously or semi-continuously deploy the semi-solid electrode slurry onto the current collector.

[0072] In some embodiments, Figure 8 As shown in , the continuous current collector can be cut to obtain a current collector having the desired current collector size in the manufactured electrode. In some embodiments, individual current collectors can be picked up from a mesh roll and placed on the top. Figure 5The conveyor system described. In some embodiments, each current collector can be placed directly on a plate, which is configured to open and close to eliminate and then generate the distance between each current collector. In some embodiments, each current collector can be picked up from a mesh reel and placed on a bag material, which is configured to become at least a part of the insulating outer coating of the electrochemical cell made. In some embodiments, the bag material can be a continuous bag material and can be fed to the plate from a roller. Without wishing to be bound by any particular theory, when a thin current collector is deployed to (e.g., coupled to) a bag material instead of being processed separately, the movement and processing of the thin current collector can be made easier. In some embodiments, the bag material in which each current collector is deployed to the surface of the bag material can be fed to a conveyor including a plate, and the plate is in an open configuration. In some embodiments, the plate can be positioned and configured so that only the bag material (without the current collector material) extends beyond the range of the plate. In some embodiments, a folding device (e.g., a flight folding machine described herein) can be used to deploy a portion of the bag material between two plates, and the plate is configured to be moved into a closed configuration to fasten the portion of the bag material therebetween. In some embodiments, when the portion of the bag material is disposed between the two plates and isolated by closing the plates, the only surface of the bag material remaining on the plates is the bag material to which the current collector is coupled. In other words, each current collector is coupled to the bag material through the portion of the current collector material therebetween, the portion of the current collector is inserted between the plates, and the remaining surface is the continuous surface of the current collector. In some embodiments, the semi-solid electrode slurry can then be disposed onto the current collector in a continuous or semi-continuous manner, and the plates can be opened to separate the individual fabricated electrodes.

[0073] In some embodiments, in an optional fifth step, the allocated semi-solid electrode slurry can be spread to a specific thickness on a continuous current collector, for example, using a scraper, a roller, a calendering process, a mobile press, or a combination thereof. In some embodiments, the semi-solid electrode slurry can be deposited on a subset of the current collector (e.g., in the middle of a 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 deployed on the semi-solid electrode slurry before the calendering step so that the semi-solid electrode slurry remains substantially deployed on the current collector rather than adhering to the calendering roller or other calendering equipment.

[0074] In some embodiments, in the sixth step, the plate can be opened to expose the inserted portion of the continuous current collector and separate discrete portions of the semi-solid electrode slurry on the continuous current collector. In some embodiments, the plate can be opened by manually forcing the plate to open and / or by accelerating the continuous current collector. In some embodiments, as Figure 6BAs shown in , the discrete portions of the semi-solid electrode slurry can be constructed to have well-formed (i.e., clean or straight) lines on both sides or more sides of the discrete portions of the semi-solid electrode slurry. In some embodiments, each discrete portion of the semi-solid electrode slurry on the current collector can be considered an electrode of an electrochemical cell.

[0075] In some embodiments, before opening the plate to expose discrete portions of the semi-solid electrode slurry, a scoring device may be used to score the semi-solid electrode slurry. In some embodiments, the scoring device may be used to score the semi-solid electrode slurry at a position substantially corresponding to the interface between the plates to facilitate clean separation of the semi-solid electrode slurry when the plates are opened. In some embodiments, the scoring mechanism may include a tensioned wire. In some embodiments, the tensioned wire may be heated or vibrated to assist in scoring the semi-solid electrode slurry. In some embodiments, the scoring mechanism may include a moving blade. In some embodiments, the scoring mechanism may include a directional fluid or air jet. In some embodiments, the scoring device may include an ultrasonic scalpel configured to separate the semi-solid electrode slurry into discrete portions. In some embodiments, the action of opening the plate may separate discrete portions of the semi-solid electrode slurry without the need for a scoring device. In some embodiments, the plate may be moved to an open configuration by moving one plate away from the other, with the other plate remaining in a fixed relative position. In some embodiments, the plate may be moved to an open configuration by simultaneously moving two plates away from each other. In some embodiments, the plates can be moved to an open configuration by moving a first interface corner of the plate away from a corresponding corner of an opposing plate and then moving another interface corner of the plate away from a second corresponding corner of the opposing plate. In other words, the plates can be rotated away from the adjacent plates if doing so facilitates a clean break of the semi-solid electrode slurry.

[0076] 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 discrete 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., a CO2 gas laser, a high-power diode laser, a fiber 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 Figure 8As shown in , 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 manufactured electrodes have not yet been coupled to the bag material, the individual electrodes can be coupled to the bag material in this step. In some embodiments, the individual electrodes can be optionally calendered to reduce the thickness of the semi-solid electrode slurry on the current collector and / or reduce defects. In some embodiments, a beta meter such as a mobile mesh thickness and / or weight measurement system can be used to ensure the appropriate and consistent z-direction thickness of the semi-solid electrode slurry on the current collector. In some embodiments, a camera and a computer processor can be used to visually inspect the manufactured electrodes and discard any defective electrodes, for example using a computer vision program.

[0077] This design provides an electrochemical cell that adopts a variety of form factors, which allows the electrochemical cell to be constructed into a specialized shape and size for a specific application. 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 varying electrode materials (e.g., semi-solid components, separators, and compartment volumes) determines the power and energy capacity of the battery.

[0078] In some embodiments, in an optional eighth step, an individualized electrode (e.g., cathode) may be paired with a separator and a second individualized electrode (e.g., anode) to form an electrochemical cell. In some embodiments, the formed electrochemical cell may be sealed on at least one edge within the bag material. In some embodiments, the formed electrochemical cell may be sealed on at least two edges within the bag material. In some embodiments, the formed electrochemical cell may be sealed on at least three edges within the bag material. In some embodiments, the formed electrochemical cell may be sealed on at least four edges within the bag material. In some embodiments, the semi-solid electrode slurry may include less electrolyte than the amount of electrolyte that the electrode made will include when it is finally formed. In some embodiments, at least a portion of the electrolyte may be added during or after the eighth step. In some embodiments, after the electrochemical cell is sealed into the bag material, the electrochemical cell may be cycled through one or more charge / discharge cycles. In some embodiments, after the initial cycle of the electrochemical cell, the bag material may be pierced to release any gas formed during the initial cycle. In some embodiments, after degassing the sealed electrochemical cell bag, the bag may be resealed along the fourth edge using a heat sealer.

[0079] Folding plug plus masking material

[0080] In some embodiments, a continuous or semi-continuous method for making a semi-solid electrode may include the above Figure 5-Figure 8The method of claim 1, wherein the plurality of electrodes are formed by a plurality of electrodes having a plurality of electrodes and a plurality of electrodes having a plurality of electrodes. The plurality of electrodes are formed by a plurality of electrodes having a plurality of electrodes and a plurality of electrodes having a plurality of electrodes. The plurality of electrodes are formed by a plurality of electrodes having a plurality of electrodes and a plurality of electrodes having a plurality of electrodes. The plurality of electrodes are formed by a plurality of electrodes having a plurality of electrodes and a plurality of electrodes having a plurality of electrodes. The plurality of electrodes are formed by a plurality of electrodes having a plurality of electrodes and a plurality of electrodes having a plurality of electrodes. Figure 1 The continuous current collector described is similar.

[0081] In some embodiments, in a first step, a portion of a continuous current collector can be deployed (eg, inserted or crimped) between two open sheets, for example using an air knife.

[0082] In some embodiments, in a second step, the two open plates can be moved to a closed configuration in which the two plates are substantially adjacent to each other and the inserted portion of the continuous current collector is held between the two plates. In some embodiments, the closing of the plates can hold the inserted portion of the continuous current collector between the plates.

[0083] In some embodiments, in the third step, a masking material may be deployed onto an 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 to define at least one edge of the current collector. In some embodiments, the edge of the current collector may be defined by limiting the extent to which the semi-solid electrode slurry may be applied. In some embodiments, the masking material may be initially stored in a rolled state and may be fed onto the current collector by a masking material dispensing system.

[0084] In some embodiments, the masking material may be applied in a direction parallel to the direction of travel of the continuous current collector. In some embodiments, the masking material may be applied before a portion of the current collector is inserted between the two plates. In other words, the masking material may be applied to the current collector, and then portions of both the current collector and the masking material may be inserted between the two plates. While the insertion of the already masked current collector has the potential to cause damage or misalignment of the masking material, it may also secure the masking material during deposition of the semi-solid electrode slurry onto the masked, inserted current collector.

[0085] In some embodiments, a masking material can be applied to the continuous current collector after the continuous current collector is unwound from a feed reel or similar device but before the semi-solid electrode slurry is deployed on the current collector. In some embodiments, a masking material can be applied to the continuous current collector before the continuous current collector is wound onto a feed reel or similar device.

[0086] In some embodiments, in a fourth step, the semi-solid electrode slurry may be deployed by a dispensing mechanism onto the masked, partially inserted continuous current collector. In some embodiments, the deployed semi-solid electrode slurry may be deployed onto the continuous current collector without being deployed onto the inserted portion of the continuous current collector. In some embodiments, some of the semi-solid electrode slurry material deployed onto the current collector may also be deployed onto the masking material. In some embodiments, the adjoining of the plates may help reduce or eliminate the loss of semi-solid electrode slurry onto the portion of the continuous current collector inserted between the two plates.

[0087] In some embodiments, in the fifth step, the masking material can be removed from the current collector surface before the two plates are moved to the open configuration. The removed masking material can be connected to a mask material recovery system. In some embodiments, the masking material recovery system may 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 the two plates are moved to the open configuration. In some embodiments, the masking material can be a closed-loop system so that the masking material can be reused in the same manufacturing process after using and cleaning the masking material. In other words, the masking material can be cleaned and returned to the beginning of the electrode manufacturing process to be applied to the current collector. In some embodiments, a more durable masking material can be used for the life of the masking material so that its use is cost-effective.

[0088] In some embodiments, in the sixth step, the plate can be opened to expose the inserted portion of the continuous current collector. In some embodiments, opening the plate can also separate discrete portions of the semi-solid electrode slurry on the continuous current collector. In some embodiments, the plate can be opened by mechanical action on the plate. In some embodiments, the plate can be opened at least in part by accelerating the delivery rate of the continuous current collector. In some embodiments, as Figure 6B As shown in , the discrete portions of the semi-solid electrode slurry can be configured to have well-formed (i.e., clean or straight) lines on both sides or more sides of the discrete portions of the semi-solid electrode slurry. In some embodiments, each discrete portion of the semi-solid electrode slurry on the current collector can be considered an electrode of an electrochemical cell.

[0089] Continuous method

[0090] Figure 9-11A method of making a semi-solid electrode in a continuous manner by covering or otherwise protecting portions of a continuous current collector from being coated by a semi-solid electrode slurry is illustrated. In some embodiments, the continuous current collector may be protected by pre-applying a masking material. In some embodiments, the masking material may be applied to the continuous current collector prior to loading the continuous current collector onto a current collector feeding device configured to feed the current collector to a conveyor (e.g., a reel feeder).

[0091] In some embodiments, the masking material may be printed onto the current collector such that the masking material is permanently disposed onto the current collector. In some embodiments, the masking material may be printed onto the current collector during manufacture of the current collector.

[0092] In some embodiments, the masking material may be applied to the continuous current collector after it is unwound from the current collector feed apparatus but before the semi-solid electrode slurry is deployed onto the masked current collector.

[0093] In some embodiments, the masking material may include any suitable material configured to removably adhere to the current collector at a range of temperatures and conditions experienced during manufacturing. In some embodiments, the masking material may be made of a polymer, a cross-linking agent, a thermoplastic polymer, a polyimide, a non-woven synthetic material, an extruded thermoformed material, paper, a metal, a natural fiber, or a combination thereof. In some embodiments, the masking material may include an adhesive such as a rubber-based adhesive, an acrylic-based adhesive, or a silicone-based adhesive.

[0094] In some embodiments, the masking material may be applied in a direction parallel and / or perpendicular to the direction of travel of the continuous current collector. In some embodiments, the masking material applied in the perpendicular direction may be applied separately from the masking material applied in the parallel direction. In some embodiments, the masking material may include a mesh structure such that the masking materials in the parallel direction and the perpendicular direction are both included in one material and applied simultaneously.

[0095] In some embodiments, this manufacturing process can be substantially fully continuous, at least in part because the plates do not need to be moved between an open configuration and a closed configuration. In some embodiments, a conveyor system can be used to move the masked current collector through a distribution mechanism (e.g., 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 rate can be substantially increased, at least to some extent, without the tradeoff of less precise, broken electrode edges.

[0096] In some embodiments, the semi-solid electrode slurry can be applied to the masked current collector using an engineered nozzle configured to precisely dispense the slurry onto the current collector. In some embodiments, the deposition of the semi-solid electrode slurry herein can be substantially the same as described above with respect to Figure 1 The methods described are similar.

[0097] In some embodiments, once the semi-solid electrode slurry is deployed onto the masked current collector, the manufacturing process may include an optional slurry spreading step. In some embodiments, the slurry spreading may be performed using a roller or a series of rollers. In some embodiments, a scraper or other similar device may be used to remove excess slurry material from the masked current collector.

[0098] In some embodiments, once the slurry has been spread substantially evenly on the current collector, the surface speed of the current collector along the conveyor can be increased to create a small gap between the formed electrodes. In some embodiments, the gap created 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 created 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.

[0099] In some embodiments, the electrode formed can be rolled by passing the formed electrode between two or more rollers to compress and optionally heat the formed electrode. In some embodiments, the formed electrode can be rolled to a specific density, for example, greater than about 1g / cm3, 1.5g / cm3, 1.75g / cm3, 2g / cm3, 2.25g / cm3, 2.5g / cm3, 2.75g / cm3, 3g / cm3, 3.25g / cm3, 3.5g / cm3, 3.75g / cm3 or greater than about 4g / cm3, including all values ​​and ranges therebetween. Without wishing to be bound by any particular theory, among other results, the rolling of the electrode can lead to a desired reduction in porosity (increase in energy density), homogenization of the z-direction thickness, and / or a reduction in contact resistance at the current collector-electrode interface.

[0100] In some embodiments, the calendering process can result in a semi-solid electrode having a porosity of less than about 99% of the porosity of the non-calendered semi-solid electrode, less than about 95%, 90%, 85%, 80%, 75%, 70%, 65%, 60%, 55%, or less than about 50%, including all values ​​and ranges therebetween. In some embodiments, a reduction in porosity to less than about 60% of the non-calendered semi-solid electrode can result in tearing or other defects in the semi-solid electrode and / or current collector.

[0101] In some embodiments, the calendering process can result in an original porosity of the semi-solid electrode of less than approximately 50%, 45%, 40%, 35%, 30%, 25%, 20%, 19%, 18%, 17%, 16%, 15%, 14%, 13%, 12%, 11%, 10%, 9%, 8%, 7%, 6%, or less than 5%, including all values ​​and ranges therebetween.

[0102] In some embodiments, after calendering, the fabricated electrode including the current collector and the semi-solid electrode slurry may have a z-direction thickness of less than about 2,000 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 fabricated electrode including the current collector and the semi-solid electrode slurry may have a z-direction thickness between about 25 μm and about 2,000 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.

[0103] In some embodiments, the mask material can be removed from the continuous current collector after the formed electrode has been optionally calendered. In some embodiments, the mask material can be connected to a mask material recovery system that is configured to force the removal of the masking material from the continuous current collector. In some embodiments, the removal of the masking material from the continuous current collector can be performed in a controlled manner so that the masking material does not remove any semi-solid electrode slurry from the formed electrode. In some embodiments, the mask material recovery system can include a subsystem for cleaning any accumulated semi-solid electrode slurry from the masking material.

[0104] In some embodiments, the removal of the masking material can create a gap between each formed electrode. In some embodiments, the gap created between each formed electrode can be sufficient to allow clean separation of each discrete formed electrode on the continuous current collector. In some embodiments, the gap created between each formed electrode can be sufficient to allow cutting of the continuous current collector to form individual electrodes.

[0105] In some embodiments, the current collector can be cut perpendicular to the direction of travel of the current collector between each discrete 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., a CO2 gas laser, a high-power diode laser, a fiber 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 Figure 8 As shown in , 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 gap created between each formed electrode after cutting the continuous current collector is insufficient, the speed of the conveyor can be increased past a specific point to create more space between adjacent formed electrodes.

[0106] In some embodiments, if the fabricated electrodes have not yet been coupled to the bag material, then each electrode can be coupled to the bag material in this step. In some embodiments, each electrode can be coupled to the bag material by heating at least a portion of the bag material to fuse the bag material to the current collector. In some embodiments, an adhesive can be used to bond the bag material to the current collector.

[0107] In some embodiments, individual electrodes may be optionally calendered 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 mobile mesh thickness and / or weight measurement system may be used to ensure the appropriate and consistent z-direction thickness of the semi-solid electrode slurry on the current collector. In some embodiments, a camera and a computer processor may be used to visually inspect the fabricated electrodes, for example using a computer vision program, and discard any defective electrodes.

[0108] In some embodiments, for example, Fig.11As shown in, the semi-solid electrode slurry can be deployed on the current collector on the roll casting (rollcasting) system. In some embodiments, the roll casting system may include a vacuum tray or a vacuum conveyor system, which is configured to convey the current collector through the manufacturing system. In some embodiments, the anode can be manufactured in the anode conveyor system, and the cathode can be manufactured in the cathode conveyor system. In some embodiments, the anode conveyor system and the conveyor system can be positioned relative to each other so that the conveyor provides the manufactured anode near the manufactured cathode to facilitate electrochemical cell assembly. In some embodiments, the separator roller feeder can provide a constant or intermittent supply of separator material between each anode and the corresponding cathode. In some embodiments, the separator can be inserted between the cathode and the anode after removing the masking material and before or after the electrode manufactured by cutting the current collector.

[0109] In some embodiments, once the masking material is removed, the conveyor system can be configured to convey the current collector through 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 calendered (before or after removing the masking material) to reduce the thickness and / or densify the semi-solid electrode material and / or remove the electrolyte.

[0110] In some embodiments, the roll casting system can be configured to continuously form cathodes and continuously form electrodes with separators continuously inserted therebetween. In some embodiments, the roll casting system can continuously form finished electrodes by sealing discrete portions of semi-solid electrode material between portions of bag material and cutting the bag material to form single individual bag units.

[0111] Endoframe

[0112] In some embodiments, a continuous or semi-continuous process for making a semi-solid electrode may include the use of an inner frame structure. In some embodiments, instead of a masking material or in addition to a masking material, the inner frame structure may be deployed on the current collector before the semi-solid electrode slurry is deployed on the current collector, as described above. In some embodiments, the inner frame may hold the current collector in place. In some embodiments, the inner frame may have at least a certain z-direction thickness such that the inner frame at least partially defines a cavity into which the semi-solid electrode slurry may be deployed and held on the surface of the current collector.

[0113] In some embodiments, the inner frame can at least partially define the surface area of ​​the electrode being made (e.g., defined as the inner extent of the inner frame). In some embodiments, the inner frame can at least partially define the thickness of the semi-solid electrode slurry on the current collector based on the z-direction height of the inner frame. 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 "scraper") or other straight-edge instrument can be used to spread the semi-solid electrode slurry. In some embodiments, the blade and / or the inner frame can be operably coupled to a vibration source to vibrate the blade or the inner frame during deposition or smoothing of the semi-solid electrode slurry. Vibration can promote dispersion of the semi-solid electrode slurry material during or after the slurry deposition step.

[0114] In some embodiments, an instrument such as an optical or any analytical tool that uses any of the non-contact measurement techniques including optical or laser interferometry, ellipsometry, or optical or laser scanning probes to examine the surface morphology and optionally measure the surface uniformity (e.g., thickness) of the spread semi-solid electrode slurry. In some embodiments, the non-contact instrument can be deployed in situ while the blade spreads the semi-solid electrode slurry.

[0115] In some embodiments, after the semi-solid electrode slurry is spread, the inner frame can be removed, leaving only the portion of the semi-solid electrode slurry that has been spread onto the exposed portion of the current collector. Alternatively, in some embodiments, after the semi-solid electrode slurry is spread, the inner frame can be kept in place and the separator can be placed on the finished electrode so that the separator, the current collector, and the inner frame each partially define the electroactive region and contain the semi-solid electrode slurry within the electroactive region.

[0116] In some embodiments, in addition to the inner frame, a masking material may be used to prevent contamination of the uncoated portions of the current collector and / or any exposed portions of the bag material. In some embodiments, the inner frame may be initially deployed onto the current collector, and a masking material may subsequently be applied to protect and / or define one, two, three, or four of the edges of the fabricated electrode. In some embodiments, the masking may extend to or out of the edge of the current collector material. In some embodiments, the masking material and the inner frame may initially be an integral piece of a single deployed material that is constructed so that the masking may be removed while the inner frame remains deployed onto the current collector. In some embodiments, after the semi-solid electrode slurry is deployed onto the current collector, the single deployed material including the inner frame and the masking material may be substantially completely removed from the current collector.

[0117] In some embodiments, the inner frame can extend beyond the edge of the current collector material so that the semi-solid electrode slurry can be deployed onto the continuous current collector more quickly and less prudently. Likewise, in some embodiments, each inner frame can be positioned and configured to be directly and securely adjacent to at least one other inner frame so that the semi-solid electrode slurry cannot be deployed onto the continuous current collector or bag material between two or more inner frames. In some embodiments, after the semi-solid electrode slurry has been deployed onto the current collector, vibration or other suitable methods can be used to remove any semi-solid electrode slurry that has accumulated on top of the inner frame structure.

[0118] In some embodiments, the inner frame and / or masking material can be constructed so that the inner frame and / or masking material naturally repels the semi-solid electrode slurry to a certain extent based on chemical, electrochemical, physical structure or other characteristics. In some embodiments, the inner frame and / or masking material can be made of a material that produces a small contact angle relative to the semi-solid electrode slurry. In some embodiments, due to the chemical differences between the anode semi-solid electrode slurry and the cathode semi-solid electrode slurry, the inner frame and / or masking material used in manufacturing the anode can be different from the inner frame and / or masking material used in manufacturing the cathode.

[0119] Continuous with scraper

[0120] Figure 12A-12C Various steps in a process of making an electrochemical cell having at least one of an anode and a cathode comprising a semi-solid electrode slurry are illustrated. Fig. 12A As shown in , at step 1, a masking material can be placed over a portion of a conductive material that can serve as a current collector for an electrochemical cell. In some embodiments, the masking material can be deployed onto the conductive material so that only the exposed portion of the conductive material visible through the masking can be used for deposition of a 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.

[0121] like Fig. 12B As shown in , at step 2, a semi-solid electrode slurry can be placed on the exposed portion of the conductive material. At 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 instrument can be used to spread the electrode. At step 5, the masking can be removed, leaving only the portion of the electrode that has been spread onto the exposed portion of the conductive material. Fig. 12CAs shown in , at step 6, a separator can be placed on a portion of the current collector so that the separator covers the electrode. At step 7, the completed semi-solid electrode and separator of step 6 can be coupled to another electrode. For example, the electrode of step 6 can be a cathode electrode, and the other electrode can include an anode electrode. At step 8, a vacuum and heat sealing process can be performed to seal the two laminated sheets together to form a finished battery, as shown in step 9.

[0122] In some embodiments, after the semi-solid electrode slurry is deposited, the cathode and anode formed can be stacked with a separator inserted. In some embodiments, the separator is first deployed to the bag material, and then the cathode can be stacked on the separator, and then the separator can be folded onto the cathode, and then the anode can be stacked on the separator, and then the separator can be folded back onto the anode. In some embodiments, this process of folding the separator back and forth and stacking the anode and cathode alternately can be performed until the appropriate number of anodes and cathodes are assembled accordingly. In some embodiments, the cathode and anode can be arranged according to a transverse or longitudinal plane and sealed by any heat sealing method described herein. In some embodiments, the resulting assembly can be folded into a zigzag shape with a separator to form a manufactured electrochemical cell. Although the use of stacking or zigzag folding has been described for continuous manufacturing processes using masking materials, or the method for processing the manufactured electrode or any other suitable method can be used with any method and system described herein.

[0123] Although various embodiments have been described above, it will be appreciated that they are presented by way of example only and not by way of limitation. Where the above schematic diagrams and / or embodiments indicate certain components arranged in certain orientations or locations, the arrangement of the components may be modified. Although embodiments have been specifically shown and described, it will be appreciated that various changes in form and detail may be made. Although various embodiments have been described as having a combination of specific features and / or components, other embodiments having any feature and / or combination of components from any embodiment described herein are possible.

[0124] The specific configuration of the various components may also vary. For example, the size and specific shape of the various components may be different from the illustrated embodiment while still providing the functionality as described herein. More specifically, the size and shape of the various components may be specifically selected for a desired or intended use. Therefore, it should be understood that, unless the context clearly indicates otherwise, the size, shape, and / or arrangement of the embodiments and / or their components may be modified for a given use.

[0125] In the case of certain events and / or processes that occur in a particular order as indicated by the above method and / or event indications, the sequencing of certain events and / or processes may be modified. In addition, certain events and / or processes may be performed simultaneously in a parallel process where possible, and sequentially as described above.

Claims

1. A method comprising: continuously dispensing a semisolid electrode slurry onto a current collector; separating the semisolid electrode slurry into discrete portions; as well as The current collector is cut to form the finished electrode.

2. The method of claim 1, further comprising: The fabricated electrode is adjoined with a second fabricated electrode interposed by a separator to form a fabricated electrochemical cell.

3. The method of claim 1, wherein: Semi-solid electrode slurries are binder-free.

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

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

6. The method of claim 4, wherein: The stationary dispensing mechanism includes a nozzle configured to dispense the semi-solid electrode slurry onto a plurality of regions of the current collector at a predetermined rate as the current collector passes the stationary dispensing 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 the z-axis.

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

10. A method for manufacturing a semi-solid electrode, comprising: inserting a portion of a current collector material between the first plate and the second plate to form a distribution surface; continuously dispensing a semisolid electrode slurry onto a dispensing surface; removing the portion of the current collector material from between the two plates to separate the semi-solid electrode slurry into discrete portions; as well as The current collector is cut to form a semi-solid electrode.

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