Method and device for producing electrodes for lithium-ion batteries

Abstract

A method for producing an electrochemical lithium-ion cell component, comprising: Advancing a substrate for a lithium-ion cell between opposing first and second calender rolls (6, 8, 106, 108, 206, 208, 306, 308, 406, 408, 506, 508); depositing particles of electrode material (16, 116, 302) comprising an active electrode material and a metal into a gap (18, 410, 510) between a first side of the substrate (20, 120, 228, 310, 413, 513) and the first calender roll (6, 106, 206, 306, 406, 506) by atmospheric plasma deposition, wherein the metal is surface-activated by the atmospheric plasma; and Pressing the deposited particles of the active electrode material and the metal particles between the first and second calender rolls (6, 8, 106, 108, 206, 208, 306, 308, 406, 408, 506, 508) to form an electrode layer (2) on the first side of the substrate.

Description

FIELD OF THE INVENTION

[0001] The patent description relates to methods and equipment for manufacturing electrodes and electrode assemblies of lithium-ion cells. INTRODUCTION

[0002] This section provides information that is helpful in understanding the invention but is not necessarily prior art.

[0003] Arrays of lithium-ion battery cells are used in numerous applications, from rechargeable batteries for laptops and other personal devices to providing motive power in automobiles. Each lithium-ion cell in a battery can provide an electrical potential of approximately three to four volts and a direct electrical current, depending on the composition and mass of the electrode materials within the cell. Lithium-ion battery cells can be discharged and recharged over many cycles. A battery can be assembled by combining an appropriate number of individual cells in a combination of parallel and series electrical connections to meet the voltage and current requirements for an electrical device or motor.For example, the assembled battery for a motor vehicle may have approximately three hundred individually packaged cells electrically connected together to provide forty to four hundred volts and sufficient electrical power for an electric traction motor to propel a vehicle.

[0004] Each lithium-ion cell typically comprises a negative electrode layer (anode during cell discharge), a positive electrode layer (cathode during cell discharge), a thin, porous separator layer placed in face-to-face contact between parallel, facing electrode layers, a liquid, lithium-containing electrolyte solution that fills the pores of the separator and contacts the facing surfaces of the electrode layers for the transport of lithium ions during repeated cell discharge and recharge cycles, and a thin layer of a metallic current collector. It is desirable to have a manufacturing process that does not waste the costly materials used in the manufacture of lithium-ion components.Because a battery requires such a large number of lithium-ion cells to provide sufficient electrical power for an electric traction motor to power a vehicle, an efficient, high-quality manufacturing process is a critical commercial consideration for this end-use.

[0005] Current production methods have several disadvantages. For example, electrodes are manufactured by painting or spraying a liquid slurry composition containing electrode material, conductive carbon materials, and a polymeric binder in a solvent system onto one or both sides of a thin metal foil serving as the current collector for the electrode. Thus, electrodes have previously been manufactured by dispersing mixtures of binders and active particulate materials in a suitable liquid and depositing the wet mixture as a coating layer of controlled thickness onto the surface of a current collector metal foil. The deposited slurry layer must then be dried, for example, in an oven to drive off the solvent and then pressed between calender rolls to fix the resin-bonded electrode particles to their respective current collector surfaces.The electrodes, formed on conductive metal current collector foil sheets of suitable area and shape, can then be cut, folded, rolled, or otherwise formed for assembly into lithium-ion cell containers with suitable porous separators and a liquid electrolyte (if required).

[0006] This current process requires a significant footprint for the production of the liquid slurry mixture and for the separate coating, drying, calendering, and assembly stations, and requires high capital investments for equipment and high energy costs, especially in the drying step. Furthermore, the use of solvents can pose health and fire hazards and also generate regulated emissions.

[0007] Gayden, published patent application US 2016 / 0254533 A1, describes the fabrication of electrode elements using an atmospheric plasma stream to heat the electrode material and deposit it onto thin substrate sheet material. The plasma stream, containing the particles, is directed onto a substrate supported on a flat work surface. Due to overspray, this deposition arrangement results in significant loss of electrode material. Gayden, published patent application DE 11 2018 001 599 T5, describes an anode component for a lithium-ion cell formed using atmospheric plasma deposition. The anode component comprises an anode material layer containing silicon particles with high lithium intercalation capacity as the active anode material in pores of a bonded layer of metal particles. The atmospheric plasma deposition process deposits metal particles and smaller silicon-containing particles simultaneously or sequentially onto an anode current collector substrate or a polymeric separator substrate for the lithium-ion cell. Schaefer, published patent application DE 10 2010 032 770 A1, describes a method for producing a multilayer electrode structure, comprising a step of forming at least two layers of the electrode structure on top of each other by thermal spraying or deposition.

[0008] It would therefore be desirable to improve the process for producing lithium-ion cells. Metal portions of the composite particles are surface-activated, surface-softened, and / or surface-melted (hereinafter collectively referred to as "surface-activated") by the atmospheric plasma, so that the deposited electrode material is compressed between the calender rolls to form a coherent electrode layer that adheres to the substrate. The calender rolls do not need to be heated, or can optionally be heated. The process can be used with cathode or anode materials deposited from the atmospheric plasma, and can be used to produce an electrode layer on a single side or both sides of the substrate and / or sandwiched between the substrates. The substrate can be in the form of individually fed sheets or in the form of a continuous roll (also referred to as a web).

[0009] One or more atmospheric plasma deposition units may be used to deposit the electrode material particles, depending on factors such as the size and deposition rate of the atmospheric plasma deposition unit, the width of the substrate, and the desired thickness and density of the electrode layer. For example, for a thicker and denser electrode layer, a plurality of atmospheric plasma deposition units may be arranged to deposit the electrode material particles in generally the same area of ​​the gap as the substrate passes between the calender rolls, thus depositing more electrode material per unit area of ​​the substrate than could be deposited with fewer atmospheric plasma deposition units.In another example, for a wider substrate, a plurality of atmospheric plasma deposition devices may be arranged to deposit the electrode material particles in generally adjacent or overlapping areas widthwise across the substrate to produce a generally uniform electrode layer across the width of the substrate. The thickness and / or density of the electrode layer may be controlled by adjusting the width of the gap in which the electrode material is deposited.

[0010] In one embodiment of the process, the lithium-ion cell substrate may be pulled through a nip between an opposing pair of calender rolls, with a first side against a first of the calender rolls, and deposition of the electrode material from an atmospheric plasma deposition device into the nip between the second side of the substrate and the second calender roll, wherein the calender rolls press the deposited electrode material into an electrode layer adhered to the second side of the substrate.A second lithium-ion cell substrate can be simultaneously nip-drawn, with a first side against the second calender roll and a second side facing the first lithium-ion cell substrate. The atmospheric plasma deposition device deposits the electrode material between the two substrates, and the calender rolls press the two substrates and the deposited electrode material together to sandwich the electrode layer between the two lithium-ion cell substrates. Surface activation in the atmospheric plasma deposition of the metal particles of the electrode material or the metal regions of electrode material composite particles causes the surface-activated metal to adhere to other particles and the substrates.For example, the lithium-ion cell substrate that is pulled through the nip with a first side against a first roll of the opposing pair of calender rolls may be a metal foil, and the second lithium-ion cell substrate that is pulled through the nip with a first side against a second roll of the opposing pair of calender rolls may be a separator sheet, or vice versa. After leaving the calender rolls, the electrode layer-substrate assembly, optionally with the second substrate on the opposite side of the electrode layer, may be cut into a shape to be assembled into lithium-ion cells, e.g., into strips that are further cut, e.g., with a laser, into individual lithium-ion cell assemblies or collected, e.g., by rolling the electrode layer-substrate assembly onto a take-up roll for later fabrication into lithium-ion cells.

[0011] In a further embodiment of the process, an electrode layer may be built up by passing through successive pairs of calender rolls, each successive pair of calender rolls being separated by a larger gap width between the rolls than the previous pair of calender rolls, so that an additional amount of electrode material can be deposited by atmospheric plasma deposition into the gap between the rolls and pressed by the rolls onto the existing electrode layer to produce a thicker electrode layer.In this embodiment, the lithium-ion cell substrate may be pulled through a nip of a first width with a first side against a first roll of a first opposing pair of calender rolls, with deposition of the electrode material from an atmospheric plasma deposition device into the nip of the first width between the second side of the substrate and the second calender roll, the calender rolls pressing the deposited electrode material into an electrode layer of a first thickness adhered to the second side of the substrate.The substrate is then pulled through a second, wider nip having a second width greater than the first width, with a first side against a first roll of a second opposing pair of calender rolls, with deposition of the electrode material by a second atmospheric plasma deposition device into the second nip between the electrode layer already present on the substrate and the second calender roll of the second pair of calender rolls, wherein the second pair of calender rolls presses the electrode material deposited by the second plasma deposition device to form an electrode layer of a second thickness greater than the first thickness on the second side of the substrate.The substrate may pass through further pairs of calender rolls that are progressively further apart, with additional electrode material being deposited by atmospheric plasma deposition into a gap between the calender rolls and onto the electrode layer to further build up the thickness of the electrode layer on the first substrate until a desired final thickness of the electrode layer is reached between a final pair of calender rolls.Optionally, a second lithium-ion cell substrate may be simultaneously pulled through the nip between the last pair of calender rolls, with a first side of the second substrate against a calender roll and a second side facing the electrode layer on the first lithium-ion cell substrate, wherein an atmospheric plasma deposition device deposits the final amount of electrode material, and the calender rolls press the two substrates and the deposited electrode material together to sandwich the electrode layer of the desired final thickness between the two lithium-ion cell substrates, which (as described above) may also be described as a metal foil and a separator sheet.In another method, after the electrode layer of the desired final thickness has been formed on the first substrate, the electrode layer and first substrate assembly may be drawn between a pair of calender rolls with the electrode layer facing a gap between the rolls, and metal particles may be deposited from an atmospheric plasma into the gap and calendered between the rolls to form a metal current collector layer on the electrode layer.The electrode layer and substrate assembly, optionally with the second substrate or plasma-deposited current collector layer on the opposite side of the electrode layer or current collector layer, can be cut into a final shape (as described above) to be assembled into lithium-ion cells or collected, for example by rolling the electrode layer-substrate assembly on a take-up reel for later manufacturing steps.

[0012] In a further embodiment, a lithium-ion cell substrate can be pulled through the gap, comprising a first layer of a first electrode material applied to a first side of the substrate by atmospheric plasma deposition, and a second layer of a second electrode material applied to a second side of the substrate by atmospheric plasma deposition; wherein, upon passing between the opposing calender rolls, the first layer is pressed between a first calender roll and the first side to form a first electrode layer, and the second layer is pressed between a second calender roll and the second side to form a second electrode layer. The first electrode material can be the same as the second electrode material, or the first electrode material can comprise a different active electrode material and / or metal than the second electrode material.In one embodiment, the first electrode material is an anode material, the second electrode material is a cathode material, and the substrate is a porous separator sheet. In this embodiment, there may be a separation between the sides of the cathode material and the anode material to prevent cross-contamination. Also in this embodiment, a first metal foil may be pulled through the nip against a first of the calender rolls, and a second metal foil may be pulled through the nip against a second of the calender rolls to be pressed into a metal foil-anode layer-porous separator-cathode layer-metal foil assembly. In another embodiment, the first electrode material and the second electrode material are either both anode materials or both cathode materials, and the substrate is a metal foil (i.e., current collector for the lithium-ion cell).In a further method, the first electrode layer is an anode layer, the second electrode layer is a cathode layer, and the anode layer-substrate-cathode layer assembly can be drawn between a second pair of calender rolls, with one or both of the electrode layers facing a gap between the rolls, and metal particles can be deposited from an atmospheric plasma into the gap and calendered between the rolls to form a metal current collector layer on one or both of the electrode layers. After exiting the calender rolls, the lithium-ion cell product assembly can be cut into a final shape for assembly into lithium-ion cells and batteries, e.g.be cut lengthwise into strips, which are further cut, for example with a laser, into individual lithium-ion cell assemblies or collected, for example by rolling the electrode layer-substrate assembly onto a take-up reel for later manufacturing steps.

[0013] In a further embodiment of the process, in which a lithium-ion cell substrate is pulled through the gap, having a first layer of a first electrode material applied by atmospheric plasma deposition to a first side of the substrate, and a second layer of a second electrode material applied by atmospheric plasma deposition to a second side of the substrate, the electrode layer may be built up on the first side or on the second side or on both sides by passing through successive pairs of calender rolls, each successive pair of calender rolls having a larger gap width between the substrate and the calender roll on the substrate side of the electrode layer being built up than that provided by the previous pair of calender rolls,so that an additional amount of the electrode material can be deposited by atmospheric plasma deposition into the gap between the substrate and the calender roll and pressed by the calender rolls to produce a thicker electrode layer. In this embodiment, the lithium-ion cell substrate can be pulled through a gap between a first opposing pair of calender rolls, with deposition of the electrode material from an atmospheric plasma deposition device into a gap of a first width between one side of the substrate and a first calender roll, and deposition of the electrode material from an atmospheric plasma deposition device into a gap of a second width between the second side of the substrate and a second calender roll, wherein the calender rolls press the deposited electrode materials into an electrode layer of a first thickness that adheres to the first side.and an electrode layer of a second thickness adhered to the second side of the substrate. The first width and the second width may be the same or different, and the first thickness and the second thickness may be the same or different. The substrate is then drawn through a second, wider nip between a second opposing pair of calender rolls, in which a further nip is present between the electrode layer and the calender roll on one or both sides of the substrate to allow the deposition of more electrode material from an additional atmospheric plasma deposition device into the nip between the electrode layer already present on the substrate and a calender roll of the second pair of calender rolls, the second pair of calender rolls pressing the deposited electrode material.to form an electrode layer of greater thickness on the substrate on one or both sides of the substrate. The substrate may pass through further pairs of calender rolls that are progressively further apart, with additional electrode material being deposited by atmospheric plasma deposition into a gap between a calender roll of each further pair and onto the electrode layer on one or both sides of the substrate to further build up the thickness of the electrode layer or to further build up the thickness of both electrode layers until a desired final thickness of the electrode layer is reached between a final pair of calender rolls. A second lithium-ion cell substrate may be simultaneously drawn through a gap between a first roll of the final pair of calender rolls and a first electrode layer.with a first side of the second substrate against a calender roll and a second side facing the electrode layer already present on the first lithium-ion cell substrate, wherein a device for atmospheric plasma deposition deposits the last amount of electrode material between the second substrate and the electrode layer on the first substrate; optionally wherein a third substrate is simultaneously drawn through a nip between a second roll of the last pair of calender rolls and a second electrode layer, with a first side of the third substrate against the second calender roll and a second side facing the second electrode layer already present on the first lithium-ion cell substrate,wherein an atmospheric plasma deposition device deposits the final amount of electrode material between the third substrate and the second electrode layer on the first substrate; and wherein the calender rolls press the substrates and the deposited electrode material together to sandwich the electrode layer(s) of the desired final thickness between the two lithium-ion cell substrates. For example, the first substrate may be a porous separator layer with an anode layer on one side and a cathode layer on the other side, and the second and third substrates may be metal foils. In another example, the first substrate may be a metal foil with anode layers on both sides, or with cathode layers on both sides.and the second and optionally a third substrate are a porous separator sheet material. In a further variation of the process, if the first substrate is a porous separator layer with an electrode layer built on one side and a cathode layer built on the other side, this assembly can be drawn through a gap between another pair of calender rolls, and metal particles can be deposited from an atmospheric plasma on one or both electrode layers and calendered between the rolls to form a current collector layer on the electrode layer or both electrode layers. The electrode layer-substrate assembly(s) can be cut (as described above) into a final shape for assembly into lithium-ion cells, or collected,for example, by rolling the electrode layer-substrate arrangement on a take-up reel for later production steps.

[0014] Also disclosed is an apparatus having a path for advancing a lithium-ion cell substrate between at least one pair of opposing calender rolls, which may optionally be heated. At least one device for atmospheric plasma deposition is arranged to deposit, by atmospheric plasma deposition, particles of electrode material comprising an active electrode material and a metal, which are supplied from a reservoir or reservoirs of particles, which is / are connected to the plasma deposition device, into a gap between a first side of the substrate and one of the pair of calender rolls. The pair of calender rolls serves toto press the deposited particles into an electrode layer on the first side of the substrate. The line may include an unwinding roll for the substrate and a take-up roll for the product substrate with an electrode layer on the first side. Instead of the take-up roll, the device may include a cutting table for longitudinally and / or transversely cutting the product substrate with the electrode layer into a desired shape for assembly in a lithium-ion cell. The device may include a plurality of atmospheric plasma deposition devices positioned along the width of the substrate and each arranged to deposit particles of electrode material from a connected reservoir or reservoirs. The active electrode material and a metal may be deposited by the plasma deposition devices simultaneously (as separate particles of metal and particles of active electrode material or as composite particles,containing both active electrode material and metal) or deposited separately by different plasma deposition devices, preferably generally uniformly and in a desired volume ratio of metal to active electrode material, into the gap across a desired portion of the width of the substrate, wherein the calender rolls have a length suitable for pressing the deposited electrode layer into an electrode layer on the substrate. In one embodiment, the path advances the substrate, which may be a metal foil or a sheet of porous separator material, against a first calender roll of the pair, and the apparatus may further include a path for advancing a second substrate, which may be the other of a metal foil or a sheet of porous separator material, against a second calender roll of the pair.so that the electrode layer is formed between the first substrate and the second substrate. In a further embodiment, the path advances the substrate through one or more pairs of calender rolls, each subsequent pair of calender rolls having a larger gap width than the immediately preceding pair of calender rolls, wherein one or more further atmospheric plasma deposition devices are arranged to deposit, by atmospheric plasma deposition, particles of electrode material comprising an active electrode material and a metal, supplied from a reservoir or reservoirs of particles connected to the plasma device, into the gap between the electrode layer and one of the pair of calender rolls, so that the thickness of the electrode layer is increased.while the substrate passes through each subsequent pair of calender rolls. Both in the embodiment with a pair of calender rolls equipped with at least one plasma deposition device for depositing electrode material and in the embodiment with a plurality of pairs of calender rolls equipped with plasma deposition devices for depositing electrode material, the disclosed apparatus may include a last pair of calender rolls equipped with one or more plasma deposition devices for depositing electrode material, as well as a path for advancing a second lithium-ion cell substrate between a roll of the last pair of calender rolls and the electrode layer formed between the last pair of calender rolls, and optionally equipped with one or more plasma deposition devices for depositing electrode material.and a path for advancing a third lithium-ion cell substrate between the other roller of the last pair of calender rollers and an electrode layer on the other side of the substrate formed between the last pair of calender rollers. In other embodiments, the apparatus may include a last pair of calender rollers equipped with at least one plasma deposition device for depositing metal particles from a supply of metal particles suitable for forming a current collector layer on the electrode layer, or, if the substrate has an electrode layer on both sides, at least one plasma deposition device for depositing metal particles from a supply into a gap between each electrode layer and a roller of the last pair of calender rollers.wherein the deposited metal particles are pressed by the last pair of calender rolls to form a current collector layer on the electrode layer.,

[0015] Also disclosed is an apparatus comprising a path for advancing a lithium-ion cell substrate between a plurality of pairs of calender rolls, wherein the rolls can optionally be heated, wherein each pair of calender rolls is equipped with one or more atmospheric plasma deposition devices configured to feed particles of electrode material comprising an active electrode material and a metal, supplied from a reservoir or reservoirs of particles connected to the plasma device, into a nip between a first side of the substrate and a roll of the pair of calender rolls, as described above, wherein each subsequent pair has a larger nip width as described above, wherein, after an electrode layer of desired thickness has been formed on one side of the substrate,the substrate path advances the substrate through the next pair of calender rolls, with the electrode layer against a first roll of the calender rolls and one or more atmospheric plasma deposition devices positioned to deposit particles of electrode material into a gap between the substrate side opposite the electrode layer and a second roll of the calender rolls. The apparatus of this embodiment can apply an electrode layer to a first side of the substrate and then apply an electrode layer to the second side of the substrate. As described above, the apparatus can optionally include a plurality of pairs of calender rolls depositing electrode material on each side to build up the thickness of the electrode layer on each side; the apparatus can optionally include a path for providing a further substrate between the electrode layer being formed.and the calender roll facing the electrode layer being formed for sandwiching the electrode layer being formed between lithium-ion cell substrates, or a pair of calender rolls equipped with at least one plasma deposition device for depositing metal particles from a supply of metal particles suitable for forming a current collector layer on the electrode layer. In these embodiments, the electrode material in the supply to the plasma deposition devices positioned on both sides of a lithium-ion cell substrate may have the same composition or different compositions.

[0016] Also disclosed is an apparatus for advancing a lithium-ion cell substrate between at least one pair of opposing calender rolls, wherein at least one atmospheric plasma deposition device with a supply of particles of electrode material comprising an active electrode material and a metal is positioned to deposit the particles of electrode material by atmospheric plasma deposition into a gap between a first side of the substrate and the first calender roll, and at least one further atmospheric plasma deposition device with a supply of particles of electrode material comprising an active electrode material and a metal is positioned to deposit the particles of electrode material by atmospheric plasma deposition into a second gap between a second side of the substrate and the second calender roll. The pair of calender rolls serves toto press the deposited particles into an electrode layer on the first side of the substrate and a second electrode layer on the second side of the substrate. The line may include an unwinding roll for the substrate and a take-up roll for the product substrate with the electrode layers on both sides. Instead of the take-up roll, the device may include a cutting table for longitudinally and / or transversely cutting the product substrate with the electrode layers on both sides into a desired shape for assembly in a lithium-ion cell. The device may include a plurality of atmospheric plasma deposition devices with a supply of particles of electrode material comprising an active electrode material and a metal, which are positioned to deposit the particles of electrode material, either together from the same deposition devices or separately from different deposition devices.generally evenly into the gaps over a desired portion of the width of the substrate so that the calender rolls can press the deposited electrode layer into an electrode layer or the substrate. If the substrate is a metal foil, the electrode material type (cathode or anode) may be the same on both sides of the metal foil (i.e., anode material supply for the plasma deposition devices on both sides or cathode material supply for the plasma deposition devices on both sides), and the apparatus may further include, on one or both sides of the metal foil, a path for providing sheet material from a porous separator between the electrode layer being formed and the calender roll facing the electrode layer being formed, to press the electrode layer being formed.sandwiched between the metal foil and the separator sheet. If the substrate is a porous separator sheet, the electrode material type in the supply (cathode or anode) may be different on the first and second sides of the porous separator sheet (i.e., a cathode layer on one side and an anode layer on the other side), and the apparatus may optionally further include a path for providing a metal foil between the electrode layer being formed and the calender roll facing the electrode layer being formed in order to sandwich the electrode layer being formed between the metal foil and the separator sheet, or alternatively, the apparatus may optionally further include at least one further pair of opposing calender rolls,in which at least one further atmospheric plasma deposition device with a supply of metal particles suitable for forming a current collector layer is positioned to deposit the metal particles by atmospheric plasma deposition into a third gap between a first side of the substrate and one roller of the pair of calendering rollers, and at least one further atmospheric plasma deposition device with a supply of metal particles suitable for forming a current collector layer is positioned to deposit the metal particles by atmospheric plasma deposition into a fourth gap between a second side of the substrate and the other roller of the pair of calendering rollers to form current collector layers on the electrode layers.

[0017] Also disclosed is an apparatus configured as in any of the above-described embodiments, in which the pair of opposed calender rolls equipped with the atmospheric plasma deposition device(s) are configured with a gap guard or closure positioned near or at the ends of the calender rolls to retain deposited electrode material and either prevent the deposition of material at an outer edge of the substrate or prevent the loss of electrode material from the ends of the calender rolls. The guard or closure may be fixed in the gap between the calender rolls or may be attached to or integrated with one or both of the calender rolls.In such an embodiment, at least one roller of the pair has a raised ring or bead at or near one or both of its ends, which may be part of the roller or a separate article fitted over the end of the roller, such as a gasket comprising, for example, a rubber such as silicone rubber, and extending toward the second roller of the pair so as to close or at least partially close the gap between that roller and the substrate. The apparatus may further include a brush or scraper edge outside the gap (i.e., in an area remote from the gap) to remove any accumulated electrode material from the raised ring, bead, or gasket.In another such embodiment, a fixed guard or shutter is inserted into the gap between substrate and a calender roll near or at one end of the calender roll to retain deposited electrode material, optionally with a path for a second substrate between the fixed guard and the calender roll.

[0018] The disclosed methods and equipment advantageously minimize waste of the active electrode material due to overspray to efficiently and economically produce electrodes and combined electrodes for lithium-ion batteries. Because the application of the electrode material to the substrate is a solid-state coating process, the disclosed methods and equipment avoid the use of solvents. As a further advantage, the disclosed methods and equipment provide high throughput of electrodes, multi-electrode arrays, half-cell arrays, and full-cell arrays for more economical production than prior methods requiring separate coating and assembly steps, and also allow easy control of the thickness and density of the applied electrode material layer. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The embodiments will be better understood by reference to the following drawings and description. The components in the figures are not necessarily to scale; rather, emphasis is placed upon illustrating the principles of the embodiments. The drawings are for the purpose of illustrating selected aspects and not all possible implementations, and are not intended to limit the scope of the present disclosure in any way. Fig. Figure 1 is a schematic illustration of a first aspect of the invention; Fig. Figure 2 is a schematic illustration of a second aspect of the invention; Fig. Figure 3 is a schematic illustration of a third aspect of the invention; Fig. Figure 4 is a schematic illustration of a fourth aspect of the invention; Fig. 5A is a detailed cross-sectional view schematically showing an arrangement for an integrated raised ring at one end of a roll of a pair of calender rolls; and Fig. Figure 5B is a detailed cross-sectional view schematically showing an arrangement for a seal over the end of each roll of a pair of calender rolls to contain electrode material while allowing the central passage of a substrate. DETAILED DESCRIPTIONDefinitions

[0020] "A," "the," "at least one," and "one or more" are used interchangeably to indicate that at least one of the items is present; a plurality of such items may be present unless the context clearly indicates otherwise. All numerical values ​​of parameters (i.e., of quantities or states) in this specification, including the appended claims, are to be understood as being modified by the term "about," regardless of whether the term "about" actually precedes the numerical value. "About" indicates that the stated numerical value allows for slight uncertainty (with some degree of accuracy in the value; approximately or reasonably close to the value).Unless the uncertainty provided by the term "about" in this ordinary sense is otherwise understood in the prior art, "about" as used herein indicates, at a minimum, deviations that may arise from ordinary measurement techniques and the use of such parameters. Furthermore, the disclosure of ranges of values ​​includes the disclosure of all values ​​and further separate ranges within the entire range.

[0021] “Active electrode material” means a lithium intercalation material that is present in either an anode or a cathode during operation of a lithium-ion cell or battery.

[0022] When used to describe the attachment of metal particles that are surface-energized, surface-softened, and / or surface-melted (collectively, "surface-activated") in an atmospheric plasma to other metal particles, active electrode material particles, or a lithium-ion cell substrate, "attached" or "adhered" means surface attachment / adhesion of the metal particles. The metal particles are adhered when they return to their original state after surface-energized activation by the atmospheric plasma. The metal particles are not completely or substantially melted. The active electrode material particles do not undergo any alteration in the atmospheric plasma.

[0023] "Atmospheric plasma" refers to a plasma produced at a temperature of up to approximately 3500 °C and a pressure approximately equal to atmospheric pressure. In an atmospheric plasma, the peak temperature reached by the particles of active electrode material is typically less than approximately 1200 °C.

[0024] The terms "comprises," "comprising," "including," and "having" are inclusive and therefore indicate the presence of the listed features, integers, steps, operations, elements, and / or components, but do not preclude the presence and addition of one or more additional features, integers, steps, operations, elements, components, and / or groups thereof. As used in this specification, the term "or" includes any combination of one or more of the items listed in connection therewith.

[0025] "Particle size" refers to the mean particle size as determined by the test method according to ISO 13320.

[0026] Each of the disclosed methods involves depositing particles of a lithium-ion cell electrode material, the particles including an active electrode material and a metal, from an atmospheric plasma deposition device into a gap between an opposed pair of calender rolls. At least one sheet of a lithium-ion cell substrate is drawn through the gap, and the calender rolls press the deposited particles into an electrode layer on one side of the sheet of the lithium-ion cell substrate to produce an electrode assembly for a lithium-ion cell. The metal is surface-activated in the atmospheric plasma, causing the electrode material to cohere and adhere to the substrate.The rate at which the particles are deposited by the atmospheric plasma deposition device(s) and the width of the gap are selected to produce an electrode layer of particles having a desired thickness and density in the electrode assembly.

[0027] A detailed description of exemplary, non-limiting embodiments follows with reference to the figures.

[0028] In Fig. 1, opposing calender rolls 6, 8 define an inner gap 18. The calender rolls 6, 8 are positioned such that the gap 18 produces a desired thickness of the electrode layer 2 between the separator sheet material 25 and the metal foil 20 in the assembly 4 of separator-electrode-metal foil emerging from the calender rolls 6, 8. In Fig. 1, the separator sheet material 25 is pulled over the calender roll 6, and the metal foil 20 is pulled over the calender roll 8. The lengths of the calender rolls 6, 8 along their axes of rotation and the widths of the separator sheet material 25 and the metal foil 20 may be substantially the same or approximately the same for efficient production of the separator-electrode-metal foil assembly and to prevent accumulation of the electrode material on the calender rolls 6, 8. Guards (not shown) may be provided at each end of the calender rolls 6, 8, extending upward to the uppermost part of or above the nip 18, to prevent leakage of the electrode material 16 (i.e., to prevent electrode material 16 from leaking out of the nip 18). In the example of Fig. 1, the separator sheet material 25 and the metal foil 20 are shown as webs that can be drawn from unwinding rolls (not shown), optionally through a feed path including tensioning rolls (not shown), with the separator-electrode-metal foil product assembly 4 being wound onto a take-up roll 30. The separator-electrode-metal foil product assembly 4 can be cut into individual electrode shapes instead of being wound onto a take-up roll 30.

[0029] Atmospheric plasma deposition device 12 and atmospheric plasma deposition device 14 deposit particulate electrode material 16 into gap 18 by atmospheric plasma deposition. Electrode material 16 includes a particulate electrode material comprising active electrode material and a metal surface-activated by the plasma. In one embodiment, particulate active electrode material and particulate metal surface-activated by the plasma are co-deposited by each atmospheric plasma deposition device, either as individual particles or as composite particles containing active electrode material and metal adhered to one another.The deposition rate of the electrode material from each atmospheric plasma deposition device may be from about 0.5 grams to about 20 grams per minute, or may be from about 1 gram to about 15 grams per minute. A sufficient number of atmospheric plasma deposition devices may be located along the length of the calender rolls 6, 8 to deposit the electrode material 16 along a desired length of the open gap.Depending on the rate at which each atmospheric plasma deposition device deposits the electrode material 16, the rate at which the separator sheet 25 and the metal foil 20 move through the gap 18, and the desired thickness of the electrode layer 2 in the separator-electrode-metal foil product assembly 4, a plurality of atmospheric plasma deposition devices may be positioned to deposit the electrode material 16 in a given area or in overlapping areas to deliver a desired amount of the electrode material 16 per unit volume into the gap between the separator sheet 25 and the metal foil 20.A portion of the electrode material 16 may be deposited by atmospheric plasma deposition onto one or both of the separator sheet 25 and the metal foil 20 at a point upstream of the gap 18, but at least a portion, preferably substantially all, and more preferably all of the electrode material 16 is deposited by atmospheric plasma deposition into the gap 18 or onto one or both of the separator sheet 25 and the metal foil 20 at a point after the substrates enter the gap 18. The gap 18 begins at an imaginary plane AA passing through the outermost circumferential points of the calender rolls 6, 8. Thus, the jet device(s) of the plasma deposition devices can be arranged such that the opening emitting the particles lies behind the plane AA and is directed into the gap 18.

[0030] In an alternative embodiment, particulate metal surface-activated by the plasma may be deposited by a first jet means of the atmospheric plasma deposition device, and particulate active electrode material may be deposited by a second jet means of the atmospheric plasma deposition device in a same region of the gap 18.

[0031] The Fig. 1 may be oriented vertically as shown, or may be oriented horizontally or at any angle between vertical and horizontal.

[0032] Atmospheric plasma generation and spray deposition equipment are commercially available. The plasma deposition equipment typically comprises a metallic tubular housing providing a flow path of a suitable length for receiving a flow of a working gas carrying dispersed particles of the electrode material and for enabling the formation of the plasma stream in an electromagnetic field established within the flow path of the tubular housing. The tubular housing typically terminates in a conically tapered outlet shaped to direct the contained particle-bearing plasma stream against the substrate (i.e., separator sheet 25 or metal foil 20) to be coated. An electrically insulating ceramic tube is typically inserted at the inlet of the tubular housing so as to extend along a portion of the flow channel.A stream of working gas, such as air, carrying the dispersed particles of electrode material is introduced into the inlet of the deposition device. The stream of air-particle mixture can be turbulently swirled in its flow path by using a swirler with flow openings inserted near the inlet end of the deposition device. A linear (pin-like) electrode can be placed in place of the ceramic tube along the flow axis of the deposition device at the upstream end of the tubular housing. During plasma generation, the electrode is powered by a high-frequency generator, for example, with a frequency of approximately 50 to 60 kHz, and a suitable potential, such as a few kilovolts. The metallic housing of the plasma deposition device is grounded, and an electrical discharge can be generated between the axial pin electrode and the housing.When the generator voltage is applied, the frequency of the applied voltage and the dielectric properties of the ceramic tube produce a corona discharge at the flow inlet and the electrode. As a result of the corona discharge, an arc discharge is formed from the electrode tip to the housing. This arc discharge is carried by the turbulent flow of the air / particulate electrode material stream to the outlet of the deposition device. A reactive plasma composed of the air (or other carrier gas, if applicable) and suspended particulate electrode material is generated at a relatively low temperature and atmospheric pressure. The outlet of the plasma deposition device is shaped to direct the particle-bearing plasma stream into the gap between the calender rolls.

[0033] The width of the separator sheet 25 and the metal foil 20 can be from about 1 mm to about 800 mm, preferably from about 5 mm to about 300 mm, and more preferably from about 30 mm to about 200 mm. The thickness of the separator sheet 25 can be from about 5 micrometers to about 30 micrometers, preferably from about 10 micrometers to about 25 micrometers, and more preferably from about 15 micrometers to about 20 micrometers. The thickness of the metal foil 20 can be from about 5 micrometers to about 25 micrometers, preferably from about 10 micrometers to about 20 micrometers, and more preferably from about 12 micrometers to about 15 micrometers. The thickness of the electrode layer 2 may be from about 5 micrometers to about 500 micrometers, preferably from about 30 micrometers to about 300 micrometers, and more preferably from about 60 micrometers to about 200 micrometers.The thickness of the separator-electrode-metal foil assembly 4 may be from about 15 micrometers to about 550 micrometers, preferably from about 60 micrometers to about 300 micrometers, and more preferably from about 85 micrometers to about 225 micrometers. The separator sheet material 25 and the metal foil 20 may enter the gap 18 at a rate of about 5 to about 150 meters per minute.

[0034] The particulate active electrode material may have particle sizes in the range of about 100 nanometers to about 100 micrometers. In one exemplary embodiment, the active electrode material may have a particle size in the range of about 1 micrometer to about 50 micrometers. The deposited electrode layer containing the active electrode material and the metal may typically be from about 5 micrometers to about 500 micrometers thick. In one exemplary embodiment, the deposited electrode layer is from about 5 micrometers to about 350 micrometers thick.

[0035] Suitable examples of active anode materials include, without limitation, lithium titanate (LTO), graphite, and silicon-based materials such as silicon, silicon alloys, SiOx, and LiSi alloys. Suitable examples of active cathode materials include, without limitation, lithium manganese nickel cobalt oxide (NMC), lithium manganese oxide (LMO), lithium cobalt oxide (LCO), lithium nickel cobalt aluminum oxide (NCA), lithium iron phosphate (LFP), and oxides and phosphates of other metals complementary to lithium. In the formation of a deposited anode layer, more than one active anode material may be deposited by atmospheric plasma deposition, and in the formation of a deposited cathode layer, more than one active cathode material may be deposited by atmospheric plasma deposition.When more than one active electrode material is deposited, the different active electrode materials can be deposited by separate atmospheric plasma deposition devices, or they can be deposited by the same atmospheric plasma deposition device. When deposited by the same atmospheric plasma deposition device, the different active electrode materials can be introduced into the atmospheric plasma as a pre-formulated mixture, or they can be introduced into the atmospheric plasma from separate feed lines.

[0036] The plasma-deposited particulate electrode material also includes a particulate metal that is surface-activated by the plasma and serves to adhere the electrode layer to the substrate. In the case of the particulate metal for the cathode layer, the metal particles may have a particle size smaller than the particle size of the active cathode material, or they may have a particle size up to approximately equal to that of the active cathode material. For example, the metal particles deposited during the fabrication of a cathode layer may have particle sizes in the range of about 1 nanometer to about 100 micrometers, or from about 10 nanometers to about 50 micrometers, or from about 100 nanometers to about 5 micrometers.In the case of the particulate metal for the anode layer, the metal particles may have a particle size approximately equal to or larger than the particle size of the active anode material. For example, the metal particles deposited during the fabrication of an anode layer may have particle sizes in the range of about 100 nanometers to about 100 micrometers, or from about 10 nanometers to about 50 micrometers, or from about 100 nanometers to about 5 micrometers. During the fabrication of an anode layer, the metal particles may comprise a metal or metals selected from, but are not limited to, copper, tin, silver, gold, nickel, palladium, platinum, and alloys thereof. During the fabrication of a cathode layer, the metal particles may comprise a metal or metals selected from, but are not limited to, aluminum, indium, thallium, titanium, zirconium, hafnium, nickel, palladium, platinum, silver, gold, and alloys thereof.

[0037] The metal particles and the active electrode materials can be deposited by separate atmospheric plasma deposition devices, or they can be deposited by the same atmospheric plasma deposition device. When deposited by the same atmospheric plasma deposition device, the metal particles and the active electrode materials can be introduced into the atmospheric plasma as a pre-formed mixture (in which the metal particles are either mixed with the active anode material or adhered to it to form composite particles), or they can be introduced into the atmospheric plasma from separate feed lines.

[0038] Fig. Figure 2 illustrates the coating of both sides of a metal foil 120 with cathode or anode material, wherein a series of plasma deposition devices and calender roll pairs are used to build up the thickness of the electrode layer through successive atmospheric plasma depositions of the electrode material, with the deposited electrode material being calendered to an increasing thickness with each successive pair of calender rolls. The plasma deposition devices 112, 114 deposit electrode material 116 on their respective opposite sides of the metal foil 120. The metal foil passes through first calender rolls 106, 108, which press the deposited electrode material to thicknesses of the electrode layer BB. The plasma deposition devices 152, 154 deposit additional electrode material on their respective opposite sides of the metal foil 120.The metal foil passes through second calender rolls 156, 158, which press the deposited electrode material to electrode layer thicknesses CC that are greater than thickness BB. Plasma deposition devices 172, 174 deposit an additional amount of electrode material on their respective opposite sides of the metal foil 120. The metal foil passes through third calender rolls 176, 178, which press the deposited electrode material to electrode layer thicknesses DD that are greater than thickness CC. The gap (also referred to as calender nip or roll gap) between the second calender rolls 156, 158 is larger than the gap between the first calender rolls 106, 108, and the gap between the third calender rolls 176, 178 is larger than the gap between the second calender rolls 156, 158, so that the electrode thickness is steadily increased as the metal foil 120 advances through each successive pair of calender rolls.It should be understood that additional plasma deposition equipment and calender roll pairs may be used to build up the electrode layer on one or both sides of a substrate as desired, and that the gaps between each side surface of the metal foil 120 or other substrate and the calender rolls may be independently selected to independently produce a desired thickness of the electrode on each major side surface of the substrate.

[0039] Fig. Figure 3 illustrates an arrangement for fabricating a lithium-ion cell component from a porous separator sheet having a cathode layer on a first side and an anode layer on a second side, and optionally further having a cathode current collector deposited on the outward-facing side of the cathode layer and an anode current collector deposited on the outward-facing side of the anode layer. A roll of porous separator sheet 228 is unwound and pulled past a separation structure 200, which may be made of a material such as a polymer or metal and is configured to keep the anode and cathode materials separate during atmospheric plasma deposition of these materials to prevent cross-contamination.Although illustrated here as a simple planar barrier, the separation structure 200 may include chambers or housings that at least partially wrap around the ends of at least one of the calender rolls 206, 208 to prevent any passage of electrode material from that side to the other side of the porous separator sheet 228. A first atmospheric plasma deposition device 212 deposits cathode material onto one side of the porous separator sheet 228 into a gap between it and the calender roll 206; a second atmospheric plasma deposition device 214 deposits anode material onto a second side of the porous separator sheet 228 into a gap between it and the calender roll 208. The porous separator sheet material 228 then passes through opposing calender rolls 206, 208, which compress the electrode layers to a desired thickness.The lithium-ion cell assembly can then be cut into a finished shape (not shown) or can be wound onto a take-up reel (not shown) for later fabrication and incorporation into lithium-ion batteries.

[0040] As in Fig. 3, metal particles 233 of a suitable metal for a cathode current collector may be deposited onto the formed cathode layer by an atmospheric plasma deposition device 252, and metal particles 235 of a suitable metal for an anode current collector may be deposited onto the formed anode layer by an atmospheric plasma deposition device 254. The porous separator sheet material 228 then passes through opposing calender rolls 256, 258, which compress the current collector layers to a desired thickness. The lithium-ion cell product component 290 may then be cut into a finished shape (not shown) or may be wound onto a take-up roll (not shown) for later forming and incorporation into lithium-ion batteries.

[0041] Fig. 4 shows another embodiment for fabricating a lithium-ion cell component from a porous separator sheet having a cathode layer on a first side sandwiched between the porous separator sheet and a cathode current collector layer, and an anode layer on a second side sandwiched between the porous separator sheet and an anode current collector. A porous separator sheet 310 is unwound from a roll 328 and pulled past a separation structure (not shown) configured to keep the anode and cathode materials separate during atmospheric plasma deposition of these materials to prevent cross-contamination. The porous separator sheet 310 passes between the calender rolls 306, 308, but does not contact either calender roll.A cathode current collector foil 337 is unwound from the roll 333 and pulled around the calender roll 306, with one side of the cathode current collector foil 337 against the calender roll 306. A first atmospheric plasma deposition device 312 deposits cathode material 302 into the gap between the porous separator sheet 310 and the cathode current collector foil 337. An anode current collector foil 327 is unwound from the roll 323 and pulled around the calender roll 308, with one side of the anode current collector foil 327 against the calender roll 308. A second atmospheric plasma deposition device 314 deposits anode material 304 into the gap between the porous separator sheet 310 and the anode current collector foil 327.The porous separator sheet 310 then passes through opposing calender rolls 306, 308, which compress the electrode layers to a desired thickness between the porous separator sheet 310 and the respective current collector foils 327, 337. The lithium-ion cell assembly 390 can then be cut into a finished shape (not shown) or wound onto a take-up roll 330 for later forming and incorporation into lithium-ion batteries.

[0042] In some embodiments, one or more calender rolls may include an integrated or non-integrated guard or closure at or near one or both roll ends. The guard or closure may prevent the electrode material particles from leaking from the sides of the gap and / or may provide a sharp edge for the electrode layer being formed on the substrate. If the substrate is a film, a guard or closure may keep one end of the film free from the electrode material coating for electrical connection during assembly into a battery. If the substrate is a porous separator, guards or closures may keep both ends of the separator free from the electrode material coating or provide a sharp edge for the electrode layer at both ends of the separator. Fig. Figure 5A shows such an arrangement in which the calender rolls 406, 408 are separated by a gap 410. The calender roll 406 has an integral end ring 450. The substrate 413 passes between the roll 408 and the ring 450. The apparatus may further include a brush or scraper (not shown) disposed on a non-engaged portion of the ring 450 to remove any adhering electrode material from the ring 450. Fig.Figure 5B shows an alternative arrangement in which the calender roll 506 has a non-integrated seal 550 and the calender roll 508 has a non-integrated seal 540 around their ends, respectively. The substrate 513 fits between the seals 540, 550, defining a gap 510 between one side surface of the substrate 513 and the roll 508, and a gap 511 between the opposite side surface of the substrate 513 and the roll 506. The seals 540, 550 contain the electrode material deposited into the gaps 510, 511 by atmospheric plasma deposition and produce sharp edges for the electrode layers formed in the gaps 510, 511. The seals 540, 550 can be cleaned by rotating them through non-engaging surface areas, or can be removed for cleaning.

[0043] Suitable porous separators are currently made from polymers such as polyethylene, polypropylene, polyethylene oxide, polyvinylidene difluoride (PVDF) and ethylene-propylene copolymers, which are filled with particulate ceramic material such as aluminum oxide (Al 2 O 3 ), silicon dioxide (SiO 7 ), magnesium oxide (MgO) or lithium-containing materials such as Li 2 Surgery 2 O 5 -B 2 O 3 , g-Li 3 PO 4 , Li 2 O-Li 2 SO 4 -B 2 O 3 , Li 4 GeO 4 / Li 3 VO 4 , Li 3 PO 4 -Li 2 S-SiS 2 , Li 2 S-SiS 2 -Li 4 SiO 4 , SiS 2 -P 2 S 5 -Li 2 S-Lil, LIPON (lithium phosphorus oxynitride): xLi 2 O:yP 2 O 5:zPON, where x ranges from about 2.8 to 3.8, y ranges from about 3.2 to 3.9, and z ranges from about 0.2 to 0.9, Li x La 2 / 3-x / 3 1 / 3-2x / 3 TiO 3 , Li 7-x La 3 Zr 2 O 12 - 0,5x (LLZO), NASICON-type glass ceramics, such as Li 1+x M x Ti 2-x (PO 4 ) 3 (M=Al, In), or LISICON type glass ceramic: Li 2+2 xZn 1-× GeO 4 .

[0044] A battery is assembled for an application by combining a suitable number of individual cells in a combination of parallel and series electrical connections to meet the voltage and current requirements for a specified electric motor. For example, in a lithium-ion battery application for an electric vehicle, the assembled battery may include up to three hundred individually packaged cells electrically interconnected to provide forty to four hundred volts and sufficient electrical power for an electric traction motor to propel a vehicle. The direct current produced by the battery can be converted to alternating current for more efficient motor operation. The separator is infiltrated with a suitable electrolyte for the lithium-ion cell.The electrolyte for a lithium-ion cell is often a lithium salt dissolved in one or more liquid organic solvents. Examples of salts include lithium hexafluorophosphate (LiPF). 6 ), lithium tetrafluoroborate (LiBF 4 ), lithium perchlorate (LiCIO 4 ), lithium hexafluoroarsenate (LiAsF 6), and lithium trifluoroethanesulfonimide. Some examples of solvents that can be used to dissolve the electrolyte salt include ethylene carbonate, dimethyl carbonate, methyl ethyl carbonate, and propylene carbonate. Other lithium salts and solvents may be used. However, a combination of lithium salt and liquid solvent is selected to provide appropriate mobility and transport of lithium ions during cell operation. The electrolyte is thoroughly dispersed within and between closely spaced layers of the electrode elements and separator layers.

[0045] The foregoing description of the embodiments has been presented for purposes of illustration and description. It is not intended to be exhaustive or limiting of the invention. Individual elements or features of a particular embodiment are generally not limited to that particular embodiment, but are, where possible, interchangeable and may be utilized in a selected embodiment even if not specifically shown or described. It may also be modified in many ways. Such variations are not to be regarded as a departure from the invention, and all such modifications are intended to be considered within the scope of the invention.

Claims

[1] A method for producing an electrochemical lithium-ion cell component, comprising: Advancing a substrate for a lithium-ion cell between opposing first and second calender rolls (6, 8, 106, 108, 206, 208, 306, 308, 406, 408, 506, 508); depositing particles of electrode material (16, 116, 302) comprising an active electrode material and a metal into a gap (18, 410, 510) between a first side of the substrate (20, 120, 228, 310, 413, 513) and the first calender roll (6, 106, 206, 306, 406, 506) by atmospheric plasma deposition, wherein the metal is surface-activated by the atmospheric plasma; and Pressing the deposited particles of the active electrode material and the metal particles between the first and second calender rolls (6, 8, 106, 108, 206, 208, 306, 308, 406, 408, 506, 508) to form an electrode layer (2) on the first side of the substrate. [2] The method of claim 1, wherein a plurality of atmospheric plasma deposition devices (12, 14, 112, 114, 152, 154, 172, 174, 212, 214, 252, 254, 312, 314) are arranged to deposit the particles of electrode material (16, 116, 302) in desired amounts and in desired area regions across a width of the substrate (20, 120, 228, 310, 413, 513). [3] The method according to claim 1 or claim 2, wherein the substrate (20, 120, 228, 310, 413, 513) is advanced against the second calender roll (8, 108, 208, 308, 408, 508), and wherein a second substrate (25, 337) for a lithium-ion cell is advanced against the first calender roll (6, 106, 206, 306, 406, 506), so that in the pressing step the electrode layer (2) is sandwiched between the substrate (20, 120, 228, 310, 413, 513) and the second substrate (25, 337). [4] The method of claim 1 or claim 2, further comprising Advancing the substrate (20, 120, 228, 310, 413, 513) with the electrode layer (2) on the first side between opposing third and fourth calender rolls (156, 158, 256, 258); Depositing additional particles of the electrode material (16, 116, 302) into a gap between the electrode layer (2) and the third calender roll (156, 256) by atmospheric plasma deposition, wherein the metal is surface-activated by the atmospheric plasma; Pressing the deposited additional particles between the third and fourth calender rolls (156, 158, 256, 258) to make the electrode layer (2) on the first side of the substrate (20, 120, 228, 310, 413, 513) thicker; and optionally advancing the substrate (20, 120, 228, 310, 413, 513) between one or more further pairs of opposing calender rolls (176, 178), on which additional particles of the electrode material (16, 116, 302) are deposited by atmospheric plasma deposition into a gap between the electrode layer and a roll of the further pair of opposing calender rolls (176, 178) and subsequently pressed by the pair of opposing calender rolls (176, 178) in order to make the electrode layer (2) thicker. [5] A method according to claim 4, wherein either (a) for the last pair of opposing calender rolls (176, 178, 256, 258) on which additional particles of electrode material (16, 116, 302) are deposited by atmospheric plasma deposition, a second substrate (25, 337) is advanced against a roll of the last pair of opposing calender rolls (176, 178, 256, 258) facing the electrode layer (2), so that in the pressing step the electrode layer (2) is sandwiched between the substrate (20, 120, 228, 310, 413, 513) and the second substrate (25, 337), or (b) wherein the substrate is a sheet material made of a porous separator (25, 228, 310), and wherein after the last pair of opposing calender rolls (176, 178, 256, 258) on which additional particles of electrode material (16, 116, 302) are deposited by atmospheric plasma deposition, the substrate (25, 228, 310) comprising the electrode layer (2) is advanced by a pair of opposing calender rolls (176, 178, 256, 258) on which particles of a metal suitable for a current collector layer are deposited by atmospheric plasma deposition into a gap between the electrode layer (2) and one roll of the pair of opposing calender rolls (176, 178, 256, 258), wherein the metal suitable for a current collector layer is surface-activated by the atmospheric plasma, and wherein the deposited particles of the metal suitable for a current collector layer,pressed between the opposing calender rolls (176, 178, 256, 258) to form a current collector layer on the electrode layer., [6] The method of claim 1 or claim 2, further comprising advancing the substrate (20, 120, 228, 310, 413, 513) having the electrode layer (2) on the first side between opposing third and fourth calender rolls (156, 158, 256, 258); Depositing particles of a second electrode material (304) comprising a second active electrode material and a second metal into a gap between the third calender roll (156, 256) and a second side of the substrate (20, 120, 228, 310, 413, 513) opposite the electrode layer (2) by atmospheric plasma deposition, wherein the metal is surface-activated by the atmospheric plasma; and Pressing the deposited particles of the second electrode material (304) between the third and fourth calender rolls (156, 158, 256, 258) to form a second electrode layer on the second side of the substrate. [7] The method of claim 1 or claim 2, further comprising depositing a second electrode material (304) comprising a second active electrode material and a second metal into a second gap between a second side of the substrate (20, 120, 228, 310, 413, 513) and the second calender roll (8, 108, 208, 308, 408, 508) by atmospheric plasma deposition, wherein the second metal is surface-activated by the atmospheric plasma; wherein the second active electrode material may be the same as or different from the active electrode material deposited on the first side, and the second metal may be the same as or different from the metal deposited on the first side; and wherein in the pressing step the deposited particles of the second electrode material (304) are pressed to form a second electrode layer on the second side of the substrate (20, 120, 228, 310, 413, 513). [8] The method of claim 7, further comprising advancing the substrate (20, 120, 228, 310, 413, 513) between one or more further pairs of opposing calender rolls (156, 158, 176, 178, 256, 258), at which additional particles of the electrode material (16, 116, 302) are deposited by atmospheric plasma deposition into a gap between the electrode layer and a roll of the further pair of opposing calender rolls (156, 158, 176, 178, 256, 258) and subsequently pressed by the pair of opposing calender rolls (156, 158, 176, 178, 256, 258) to make the electrode layer (2) thicker, and / or additional particles of the second electrode material (304) by atmospheric plasma deposition into a gap between the second electrode layer and the other roll of the further pair of opposing calender rolls (156, 158, 176, 178, 256,258) and then pressed through the pair of opposing calender rolls (156, 158, 176, 178, 256, 258) to make the second electrode layer thicker. [9] A method according to claim 8, wherein either (a) during a final pressing step, the electrode layer (2) is sandwiched between the metal foil (20, 120) and a sheet material made of a porous separator (25, 228, 310), and optionally the second electrode layer is sandwiched between the metal foil (20, 120) and a second sheet material made of a porous separator (25, 228, 310), or (b) wherein the substrate (20, 120, 228, 310, 413, 513) is a sheet material made of a porous separator (25, 228, 310) and wherein the electrode layer (2) is an anode layer and the second electrode layer is a cathode layer, and during a final pressing step the electrode layer (2) is sandwiched between the sheet material made of a porous separator (25, 228, 310) and a first metal foil (20, 120), and optionally wherein the second electrode layer is sandwiched between the sheet material made of a porous separator (25, 228, 310) and a second metal foil. [10] The method of claim 7, further comprising Pulling the substrate (20, 120, 228, 310, 413, 513) with the electrode layer (2) and the second electrode layer between a further pair of opposing calender rolls; Depositing particles of a current collector metal into a gap between the electrode layer and one roller of the further pair of calender rolls (156, 158, 256, 258) by atmospheric plasma deposition, and optionally depositing particles of a second current collector metal into a gap between the second electrode layer and the other roller of the further pair of calender rolls (156, 158, 256, 258) by atmospheric plasma deposition, wherein the particles of the current collector metal and the second current collector metal may be the same or different and are surface-activated by the atmospheric plasma;and pressing the deposited particles of the current collector metal and, if deposited, the deposited particles of the second current collector metal between the further pair of opposing calender rolls (156, 158, 256, 258) to form a current collector on the electrode layer (2) and, if deposited, to form a second current collector on the second electrode layer; [11] Device comprising: a path for advancing a lithium-ion cell substrate (20, 120, 228, 310, 413, 513) between a pair of opposing calender rolls (6, 8, 106, 108, 206, 208, 306, 308, 406, 408, 506, 508); at least one atmospheric plasma deposition device (12, 112, 212, 312) arranged to deposit, from a supply connected thereto, particles of an electrode material (16, 116, 302) comprising an active electrode material and a metal into a gap between a first side of the substrate and a first of the opposing calender rolls (6, 106, 206, 306, 406, 506); wherein the pair of opposing calender rolls (6, 8, 106, 108, 206, 208, 306, 308, 406, 408, 506, 508) is operable to press the deposited particles of the electrode material (16, 116, 302) into an electrode layer (2) on the first side of the substrate (20, 120, 228, 310, 413, 513). [12] Apparatus according to claim 11, further comprising at least one atmospheric plasma deposition device (14, 114, 214, 314) on the second side, which is arranged to deposit, from a supply connected thereto, particles of a second electrode material (304) comprising a second active electrode material, which may be the same as or different from the active electrode material, and a second metal, which may be the same as or different from the metal, into a second gap between a second side of the substrate (20, 120, 228, 310, 413, 513) and a second roll (8, 108, 208, 308, 408, 508) of the opposed calender rolls (6, 8, 106, 108, 206, 208, 306, 308, 406, 408, 506, 508), wherein the pair of opposing calender rolls (6, 8, 106, 108, 206, 208, 306, 308, 406, 408, 506, 508) is operable,to press deposited particles of the electrode material (304) into a second electrode layer on the second side of the substrate (20, 120, 228, 310, 413, 513). [13] Apparatus according to claim 11 or claim 12, either (a) further comprising a path for advancing a second lithium-ion cell substrate (25, 337) around the first of the opposing calender rolls (6, 106, 206, 306, 406, 506) and facing the nip, and optionally a path for advancing a third lithium-ion cell substrate (327) around the second of the opposing calender rolls (8, 108, 208, 308, 408, 508) and facing the second nip, or (b) comprising a second pair of opposed calender rolls (156, 158, 256, 258) with at least one atmospheric plasma deposition device (152, 252) arranged to deposit, from a supply connected thereto, particles of a metal suitable for a current collector layer into a gap between the electrode layer (2) and a first of the opposed calender rolls (156, 256); wherein the second pair of opposed calender rolls (156, 158, 256, 258) is operable to press the deposited particles of a metal suitable for a current collector layer into a current collector layer on the electrode layer (2). [14] Apparatus according to claim 11 or claim 12, further comprising a second pair of opposed calender rolls (156, 158, 256, 258) having at least one atmospheric plasma deposition device (152, 252) arranged to deposit, from a supply connected thereto, particles of a metal suitable for a current collector layer into a gap between the electrode layer (2) and a first of the opposed calender rolls (156, 256); wherein the second pair of opposed calender rolls (156, 158, 256, 258) is operable to press the deposited particles of the metal suitable for a current collector layer into a current collector layer on the electrode layer (2). [15] The apparatus of claim 11, further comprising a path for advancing a lithium-ion cell substrate (20, 120, 228, 310, 413, 513) between another pair or a plurality of another pairs of opposed calender rolls (156, 158, 176, 178, 256, 258); at least one atmospheric plasma deposition device (152, 172, 252) arranged to deposit, from a supply connected thereto, particles of an electrode material (16, 116, 302) comprising an active electrode material and a metal into a gap between a first side of the substrate (20, 120, 228, 310, 413, 513) and a first roll of the further pair or a first roll of each of the plurality of further pairs of opposed calender rolls (156, 176, 256); wherein the further pair or each of the plurality of further pairs of opposed calender rolls (156, 158, 176, 178, 256, 258) is operable to press the deposited particles of the electrode material (16, 116, 302) into an electrode layer on the first side of the substrate (20, 120, 228, 310, 413, 513) that is thicker than the electrode layer (2) produced by the previous pair of opposed calender rolls (6, 8, 106, 108, 206, 208, 306, 308, 406, 408, 506, 508). [16] Apparatus according to claim 15, further comprising at least one atmospheric plasma deposition device (14, 114, 154, 174, 214, 254, 314) on the second side arranged to deposit, from a supply connected thereto, particles of a second electrode material (304) comprising a second active electrode material, which may be the same as or different from the active electrode material, and a second metal, which may be the same as or different from the metal, into a second gap between a second side of the substrate (20, 120, 228, 310, 413, 513) and a second roll of each of the opposing pairs of calender rolls (8, 108, 158, 178, 208, 258, 308, 408, 508), each of the pairs of opposing Calender rolls (6, 8, 106, 108, 156, 158, 176, 178, 206, 208, 256, 258, 306, 308, 406, 408, 506, 508) can be actuated,to press deposited particles of the second electrode material (304) into a second electrode layer on the second side of the substrate (20, 120, 228, 310, 413, 513), and wherein each successive pair of opposed calender rolls (156, 158, 176, 178, 256, 258) is arranged to produce an electrode layer that is thicker than the electrode layer (2) produced by a preceding pair of opposed calender rolls (6, 8, 106, 108, 206, 208, 306, 308, 406, 408, 506, 508). [17] The apparatus of claim 15 or claim 16, further comprising a path for advancing a second lithium-ion cell substrate (25, 337) around the first of the opposed calender rolls (176, 256) of a last pair of opposed calender rolls (176, 178, 256, 258). [18] The apparatus of claim 16, further comprising a path for advancing a second lithium-ion cell substrate (25, 337) around the first of the opposed calender rolls (176, 256) of a last pair of opposed calender rolls (176, 178, 256, 258), and a path for advancing a third lithium-ion cell substrate (327) around the second of the opposed calender rolls (178, 258) of the last pair of the plurality of pairs of opposed calender rolls (176, 178, 256, 258). [19] Apparatus according to claim 15 or claim 16, comprising a last pair of opposed calender rolls (176, 178, 256, 258) having at least one atmospheric plasma deposition device (172, 252) arranged to deposit, from a supply connected thereto, particles of a metal suitable for a current collector layer into a gap between the electrode layer and a first roll of the last pair of opposed calender rolls (176, 256); wherein the last pair of opposed calender rolls (176, 178, 256, 258) is operable to press the deposited particles of a metal suitable for a current collector layer into a current collector layer on the electrode layer (2). [20] Apparatus according to claim 16, further comprising a last pair of opposed calender rolls (176, 178, 256, 258) with at least one atmospheric plasma deposition device (172, 252) arranged to deposit, from a feed connected thereto, particles of a metal suitable for a current collector layer into a gap between the electrode layer (2) and a first roll of the last pair of opposed calender rolls (176, 256), and at least one atmospheric plasma deposition device (174, 254) arranged to deposit, from a feed connected thereto, particles of a metal suitable for a current collector layer into a second gap between the second electrode layer and a second roll of the last pair of opposed calender rolls (178, 258), wherein the second pair of opposed calender rolls (156, 158, 256, 258) is operable to press the deposited particles of the metal suitable for a current collector layer into a current collector layer on the electrode layer (2) and a current collector layer on the second electrode layer.

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