Tabletless energy storage device and its manufacturing method

Abstract

An energy storage device, such as a lithium-ion battery, without tabs connecting the electrode jelly roll to the can, and a method for making the same, is described. A series of flags may be cut, bent, and interleaved with one another to form connection points for upper and lower collector plates within the can. The upper and lower collector plates can be welded directly to the interleaved flags to form connection points for the anode and cathode in the energy storage device.

Description

[Technical Field]

[0001] [CROSS-REFERENCE TO RELATED APPLICATIONS] Any application for which a foreign or domestic priority claim is identified in an Application Data Sheet or application filed with this application is incorporated by reference under 37 CFR 1.57 and Rules 4.18 and 20.6, including U.S. Provisional Application No. 63 / 081,244, filed September 21, 2020, and U.S. Provisional Application No. 63 / 167,565, filed March 29, 2021.

[0002] The present disclosure relates to energy storage devices and methods of manufacturing the same, and more particularly to battery cells having a tabless cathode and anode and methods of manufacturing the battery cells. [Background technology]

[0003] Many types of battery cells are currently used as energy sources in electric vehicles and energy storage applications. Many current cells use a jelly roll configuration in which the cathode, anode, and separator are wound together, with cathode and anode tabs for connecting to the positive and negative terminals of the cell can.

[0004] The path of current naturally travels through these tabs to a connector outside the battery cell. However, if the current must travel out of the cell across the cathode or anode to the tab, ohmic resistance increases with distance. Furthermore, because the tab is an additional component, it adds more thickness to the device and must itself be wound into a jelly roll, increasing cost and presenting manufacturing challenges. Summary of the Invention

[0005] For purposes of summarizing the invention and the advantages achieved over the prior art, certain objects and advantages of the invention are described herein. Not all such objects or advantages may be achieved in any particular embodiment of the invention. Thus, for example, it will be apparent to those skilled in the art that the invention may be embodied or implemented to achieve or optimize one advantage or advantages as taught herein without necessarily achieving other objects or advantages that may be taught or suggested herein.

[0006] One aspect is a method of making a battery cell with an anode or cathode having a series of flags formed from foil sections at the top and bottom of each electrode, where the flags are folded over at each end to form an alternating flower shape.

[0007] In another aspect, a method of making a tabless energy storage device is described that includes providing an electrode layer having an active material disposed over a foil, forming a series of flags on the foil to form a flagged electrode, winding the flagged electrode to form an electrode roll comprising a series of wound flags, and electrically connecting the wound flags to a current collector to form the energy storage device.

[0008] In another aspect, a method of making a wound electrode is described, the method including providing an electrode layer comprising an active material disposed over a foil, forming a series of flags on the foil to form a flagged electrode, winding the flagged electrode to form an electrode roll comprising a series of wound flags, and folding the wound flags to form folded wound flags, wherein each flag of the folded flags is oriented into a substantially interleaved configuration.

[0009] In another aspect, a method of making a wound electrode is described that includes providing an electrode layer comprising an active material disposed over a foil, forming a series of flags on the foil to form a flagged electrode, folding the flags to produce a folded flagged electrode comprising a series of folded flags, and winding the folded flagged electrode to form an electrode roll, wherein the folded flags are oriented into a substantially interleaved configuration as the folded flags are wound.

[0010] In another aspect, an interleaved flagged electrode is described, the electrode comprising a wound flagged electrode layer comprising an active material disposed over a foil, the foil comprising a series of flags, each of which is folded into a substantially interleaved configuration.

[0011] All of these embodiments are intended to be within the scope of the invention disclosed herein. These and other embodiments of the present invention will become readily apparent to those skilled in the art from the following detailed description of the preferred embodiments, taken in conjunction with the accompanying drawings, and the invention is not limited to any particular preferred embodiment disclosed. [Brief explanation of the drawings]

[0012] [Figure 1A] A perspective view of a battery cell can is shown.

[0013] [Figure 1B] A side view of the battery cell can is shown.

[0014] [Figure 2] 1A-1C show perspective views of material layers in a battery electrode of one embodiment of the present invention during a flag folding process.

[0015] [Figure 3A] 10 shows an image of a battery electrode with folded and interleaved flag features.

[0016] [Figure 3B] 3B shows a CT image of a cross section of the battery electrode of FIG. 3A showing the interleaved folded flags on top.

[0017] [Figure 3C] 1 shows split images of the structure of a battery electrode with interleaved flag features, where the left split image is a structural model of a flower design obtained by forming a jelly roll using interleaved flags, and the right split image is a density map model of the flags on the jelly roll.

[0018] [Figure 3D] 10 is a schematic diagram showing possible angles of the electrode flags. FIG.

[0019] [Figure 4] FIG. 1 is a schematic diagram of a jelly roll cross section of one embodiment of a cathode and anode with folded flags.

[0020] [Figure 5A] 10 illustrates an embodiment of upper and lower current collectors with cutouts.

[0021] [Figure 5B] 10 is an image of the upper current collector showing the laser weld on the cutout.

[0022] [Figure 5C] 1 is a series of images of a jelly roll having upper and lower current collectors with different patterns of laser welds.

[0023] [Figure 6A] 1 shows an electrode roll with a cap or top edge that is used to compress and fold the flags at the ends of the roll into an interleaved position.

[0024] [Figure 6B] 6A shows a top image that can be used to compress the flag as shown in FIG. 6A.

[0025] [Figure 7A] FIG. 10 is a perspective view of a directional air ring and press for interleaving electrode flags.

[0026] [Figure 7B] FIG. 7B is a cross-sectional cutaway view of the directional air ring of FIG. 7A showing the internal air channels and outlets.

[0027] [Figure 8] FIG. 10 shows a perspective view of a set of diverters and rollers for folding the electrode foil flags before winding.

[0028] [Figure 9] 10 shows a perspective view of a roller and wedge configuration for folding the electrode foil flag before winding. FIG.

[0029] [Figure 10] 10 shows a perspective view of a press roller and anvil configuration for folding the electrode foil flag before winding. FIG.

[0030] [Figure 11A] FIG. 10 illustrates the problem of flags interfering with each other when the electrode is wound onto a roll.

[0031] [Figure 11B] FIG. 10 illustrates a flag management system being used to move or shift flags into staggered positions relative to one another so that the trailing edge of one flag is under the leading edge of an adjacent flag as the roll is wound.

[0032] [Figure 12] FIG. 1 is a schematic diagram of an inspection device that can be used to inspect an electrode roll.

[0033] [Figure 13A] 1 is a set of images illustrating a process for inspecting flag formation in a wound electrode roll.

[0034] [Figure 13B] 1 is an image of an incorrectly formed electrode roll under inspection. [Figure 13C] 1 is an image of an incorrectly formed electrode roll under inspection. [Figure 13D] 1 is an image of an incorrectly formed electrode roll under inspection. DETAILED DESCRIPTION OF THE INVENTION

[0035] The present disclosure relates to energy storage device cells and methods of making cells for energy storage devices, such as lithium-ion batteries, having tabless connections from the anode and cathode conductors to a can. In one example, in a jellyroll cell configuration, negative and positive electrodes are formed to include flag structures on their edges for making electrical connections to the battery can. As each flagged electrode is wound in the jellyroll configuration, the flags can be pressed inward to form an interleaved "flower" or "artichoke" shaped configuration at each end of the jellyroll. The folded flags can be joined (e.g., pressed, soldered, laser welded, etc.) to the top and bottom current collectors at the ends of the battery cell to form a cylindrical unit. The cylindrical unit can then be loaded into a battery can for final processing to form a lithium-ion battery.

[0036] Each electrode can have tens or hundreds of flags, and the flags can be any configuration. For example, the flags may be spaced very close together to form a flower shape when wound into a jelly roll. In other embodiments, the flags can be spaced so that each flag aligns with the other flags to form a single line of flags on one side of the jelly roll. In one embodiment, the flags are spaced so that they are interleaved when the jelly roll is formed. In one embodiment, the interleaved flags can be compressed into a flat or substantially flat configuration at each end of the cell.

[0037] In one embodiment, each end of the cell is capped with a current collector. The current collector may be a solid, circular metal structure. In other embodiments, notches may be formed that act to relieve axial or torsional stresses from the components within the jelly roll. For example, a set of triangles, circles, squares, rectangles, or other geometric shapes may be cut out of the current collector to give the current collector greater ability to flex under stresses imposed on the battery cell.

[0038] Reference will now be made in detail to certain aspects or features, examples of which are illustrated in the accompanying drawings. Wherever possible, corresponding or like reference numbers are used throughout the drawings to refer to the same or corresponding parts.

[0039] FIG. 1 shows a battery cell 100 in a perspective view in FIG. 1A and a side view in FIG. 1B. Referring to FIGS. 1A and 1B together, the battery cell 100 may be any type of conventional battery cell capable of converting chemical energy of materials stored in the battery cell 100 into electrical energy. The battery cell 100 has a first end 102 and a second end 104. The battery cell 100 has a positive terminal 106 and a negative terminal 108 toward the first end 102. The positive terminal 106 preferentially protrudes from the first end 102 of the battery cell 100 to enable access to the positive terminal 106 and distinguishes the first end 102 from the second end 104, although different shapes of the positive terminal 106 may exist. The negative terminal 108 preferentially begins at the second end 104 and continues at an exterior surface 110 of the battery cell 100, covering at least a portion of the first end 102. The portion of the battery cell 100 that covers the outer surface to the first end may be referred to as the "shoulder" of the battery cell 100. The negative terminal 108 is preferably formed on the shoulder, so that connection to the negative terminal can be made at the shoulder. That is, the negative terminal 108 is preferentially located on the shoulder of the battery cell 100. An insulating region 112 may be provided on the surface 110 of the battery cell 100 to prevent the positive terminal 106 and the negative terminal 108 from contacting each other and shorting out. The insulating region 112 may also be provided on the region of the surface 110 between the positive terminal 106 and the negative terminal 108 via any other means. In an alternative embodiment, the positive and negative terminals may be switched.

[0040] As shown in FIG. 2 , jelly roll 200 includes first substrate 202 having first coating 210 disposed on a side of first substrate 202. In some embodiments, first coating 210 may be disposed on both sides of first substrate 202 to form a dual-layer electrode. In some embodiments, first substrate 202 is preferably embodied in the form of a laminate having a thickness of a predetermined magnitude, for example, within a range of 0.01 to 1 millimeter (mm). In some embodiments, first substrate 202 comprises a current collector. In some embodiments, the current collector comprises a metal foil. In some embodiments, the current collector comprises aluminum or copper.

[0041] In some embodiments, the first coating 210 may be a conductive coating having a first amount of conductivity. In some embodiments, the first coating 210 may be an electrode film. In some embodiments, the conductive coating comprises an electrode active material. In some embodiments, the electrode active material is a cathode active material. In some embodiments, the electrode active material is an anode active material. In some embodiments, the electrode active material is a silicon material, a graphitic material, graphite, a graphene-containing material, hard carbon, soft carbon, carbon nanotubes, porous carbon, conductive carbon, lithium nickel manganese cobalt oxide (NMC), lithium manganese oxide (LMO), lithium iron phosphate (LFP), lithium cobalt oxide (LCO), lithium titanate (LTO), lithium nickel cobalt aluminum oxide (NCA), layered transition metal oxides (e.g., LiCoO (LCO), Li(NiMnCo)O (NMC), and / or LiNi 0.8 Co 0.15 Al 0.05 O2 (NCA)), spinel manganese oxide (LiMn2O4 (LMO) and / or LiMn 1.5 Ni 0.5O4 (LMNO), olivine (e.g., LiFePO4), chalcogenides (LiTiS2), tavorite (LiFeSO4F), silicon, silicon oxide (SiOx), aluminum, tin, tin oxide (SnOx), manganese oxide (MnOx), molybdenum oxide (MoO2), molybdenum disulfide (MoS2), nickel oxide (NiOx), copper oxide (CuOx), and lithium sulfide (Li2S), and combinations thereof.

[0042] In some embodiments, the first coating further comprises a binder. In some embodiments, the first coating 210 may be disposed on the first substrate 202 by any means known to one of ordinary skill in the art. Some examples of disposing the first coating 210 on the first substrate 202 include, but are not limited to, mechanical deposition, electromechanical deposition, electrochemical deposition, or any combination of processes known to one of ordinary skill in the art.

[0043] Additionally or optionally, a foil portion 212 of first substrate 202 is formed midway along width W of first substrate 202 and includes a series of lower flags 218. As shown, a jellyroll is then formed, with lower flags 218 wound around central axis AA'. In some embodiments, lower flags 218 are exposed regions (e.g., current collectors) of first substrate 202. In some embodiments, conductive portion 218 consists of or consists essentially of first substrate 202.

[0044] The inner separator 204 is disposed over the first substrate 102 (e.g., stacked on the first substrate 102). In some embodiments, the inner separator 204 is in the form of a laminate having a thickness of a predetermined magnitude, for example, in the range of 0.01 to 0.05 millimeters (mm). In some embodiments, the inner separator is 10 μm, 15 μm, 20 μm, 30 μm, 40 μm, or 50 μm, or any range of values ​​therebetween (e.g., 10 to 15 μm), or approximately such values. Further, in some embodiments, the inner separator 204 is electrically insulating. In some embodiments, the inner separator may comprise a polymeric material. In some embodiments, the inner separator may be selected from polyethylene, polypropylene, or a combination thereof. In some embodiments, the inner separator comprises multiple separator layers. In some embodiments, the inner separator comprises micropores.

[0045] Second substrate 206 is disposed over inner separator 204 (e.g., stacked on inner separator 204). Second substrate 206 has second coating 220 disposed on one side of second substrate 206. In some embodiments, second coating 220 may be disposed on both sides of second substrate 206. In some embodiments, second substrate 206 is in the form of a laminate having a thickness of a predetermined size, for example, within a range of 0.01 to 1 millimeter (mm). In some embodiments, second substrate 206 comprises a current collector (e.g., foil).

[0046] The second coating 220 is a conductive coating having a second amount of conductivity. In some embodiments, the second coating 220 may be an electrode film. In some embodiments, the conductive coating includes an electrode active material. In some embodiments, the electrode active material is a cathode active material. In some embodiments, the electrode active material is an anode active material. In certain embodiments, the second coating 220 may be similar or the same as the first coating 210 and therefore may have a similar or the same conductivity. In certain other embodiments, the second coating 220 may be different from the first coating 210 and therefore may have a different conductivity. In some embodiments, the second coating 220 may be disposed on the second substrate 206 by any means known to those skilled in the art. Some examples of disposing the second coating 220 on the second substrate 206 include, but are not limited to, mechanical deposition, electromechanical deposition, electrochemical deposition, or any combination of processes known to those skilled in the art.

[0047] The outer separator 208 may be disposed over the second substrate 206 (e.g., stacked on the second substrate 206). In some embodiments, the outer separator 208 is in the form of a laminate having a predetermined thickness, for example, within a range of 0.01 to 0.05 millimeters (mm). Furthermore, the outer separator 208 is electrically insulating. When the first substrate 202, the inner separator 204, the second substrate 206, and the outer separator 208 are sequentially stacked, the first substrate 202, the inner separator 204, the second substrate 206, and the outer separator 208 are wound around the central axis AA' with the first substrate 202 closest to the central axis AA'.

[0048] As shown, second substrate 206 includes a series of flags 206A formed from foil that are in communication with second substrate 206. These flags 206A are wrapped around the top layer of the jellyroll to form a flower or artichoke shape when bent toward central axis AA' as the jellyroll is formed.

[0049] Figure 3A is a photograph showing one embodiment of an anode with an upper flag that is folded to form a flower structure, and Figure 3B is a CT scan of a cross section of the device of Figure 3A, showing that the folded flags are in electrical communication with each other but not with any portion of the cathode material shown at the bottom of Figure 3B.

[0050] 3C shows split images of a battery electrode structure with flag features, where the split image on the left is a structural model of a flower design obtained by using flags to form a jelly roll, and the split image on the right is a density map model of the flags on the jelly roll. As shown, in this embodiment, the flags are relatively square in shape. Of course, it should be understood that any relevant geometric shape, such as rectangular, triangular, or trapezoidal shaped flags, can similarly be used to form the flag structure from the anode or cathode.

[0051] FIG. 3D illustrates that the flags can be angled in one direction. In one embodiment, the flags are angled toward the jelly roll. In other embodiments, the flags are angled away from the jelly roll. The flags, in one embodiment, may be angled from 0 to 30 degrees or more, including 5 to 10 degrees, 11 to 20 degrees, 21 to 30 degrees, 10 to 15 degrees, or any number in between, including, for example, about 10 degrees, 10.5 degrees, 11 degrees, 11.5 degrees, 12 degrees, 12.5 degrees, 13 degrees, 13.5 degrees, 14 degrees, 14.5 degrees, or 15 degrees. Each flag may be 1 to 10 mm high and 1 to 10 mm wide. For example, the flags may be 3 to 6 mm high and 3 to 6 mm wide.

[0052] Figure 4 is a cross-sectional side view of one embodiment of a jelly roll. This configuration includes an anode 405 connected to a copper flag 408. Insulators 410A and 410B prevent the anode material from contacting the adjacent cathode 415. The cathode 418 is electrically connected to an aluminum flag 418. As can be seen by examining Figure 4, each anode section in the jelly roll is connected to an upper copper flag, and each cathode section in the jelly roll is connected to a lower aluminum flag.

[0053] FIG. 5A shows an aluminum current collector 500 that connects from the cathode to the aluminum flags. As can be imagined from examining FIG. 3A, the current collector is positioned on top of the flower structure formed by the interleaved flags. The current collector compresses the flags and allows electrical connection across the large surface area of ​​the flower structure formed from the flags. As shown, each current collector 500 includes a series of cutout sections 510A, 510B that act to provide strain relief from any twisting motion of the electrodes within the cylinder. FIG. 5A also shows a copper current collector 525 with cutouts 530A, 530B that connect to the anode.

[0054] 5B and 5C show copper and aluminum current collectors laser welded from the top end of the current collector weld to flags formed on the top and bottom ends of each cylindrical unit. While the laser welds are shown as circles in the figures, it should be understood that they are not limited to that particular shape. Laser welds of lines, curves, circles, and other geometric shapes are all contemplated within the scope of the present invention. In some embodiments, the flags can be connected to the current collectors by crimping, solder joints, welding (e.g., laser welding), and combinations thereof. Manufacturing method

[0055] Tabless energy storage devices can be manufactured in high speed and / or high volume processes suitable for commercial manufacturing. An embodiment of a method of forming the device can include starting with an electrode comprising a lithium ion current collector and a foil portion positioned at an end of the width of the electrode.

[0056] Once the electrodes are applied, a series of flags are formed from the foil portion of each electrode to create a flagged electrode. In some embodiments, the flags are created by forming slits in the foil portions of the positive and negative electrodes as described above. In some embodiments, the slits are formed by cutting or laser etching the foil. In some embodiments, the series of flags are formed in a pattern such that when the electrode is wrapped, the flags are configured to form a "flower" or "artichoke" shaped formation. The flags may be interleaved, where the trailing edge of one flag is folded under the leading edge of an adjacent flag.

[0057] The flagged electrodes are wound into a "jelly roll" to form an electrode roll comprising a series of wound flags. In some embodiments, the series of wound flags is substantially straight (i.e., not folded) so that each flag does not substantially overlap other flags in the electrode roll. In some embodiments, the series of wound flags is folded toward the interior of the electrode roll.

[0058] To form a "flower" or "artichoke" shaped configuration of the flags of the electrode roll, the flags are folded toward the centerline (i.e., central axis) of the electrode roll. In some embodiments, a series of flags are folded after winding. In some embodiments, the jelly roll is wound first, and then the flags are folded toward the centerline of the jelly roll after winding. In some embodiments, the flags are folded sequentially or continuously from the outer portions of the flags toward the inner portions of the flags. In some embodiments, successive folds are performed on each or groups of flags. In some embodiments, the successive folds are performed by rollers as the jelly roll is rotated, pressing against the outermost flags first and then moving successively inward, interleaving each circumferential set of flags under one another.

[0059] In some embodiments, post-rolling folding of the flags is performed on all or substantially all of the flags simultaneously. For example, as shown in FIG. 6A, a press or cap (FIG. 6B) can be placed over the top of a set of flags at each end of the jelly roll to bend the flags toward the centerline of the jelly roll. In some embodiments, the simultaneous folding is performed by a press. In some embodiments, the press is selected from a flat press, a dome press, and combinations thereof. In some embodiments, the jelly roll or cap or press is rotated to help fold, press down, and interleave the flags toward the centerline to form the configuration shown in FIGS. 3A-3C.

[0060] In some embodiments, a directional air ring or "blow ring," as shown in FIGS. 7A and 7B, comprises a ring-shaped device that can accommodate the ends of a jelly roll. Holes in the central circumference of the ring are positioned or configured to output compressed air at an angle to create an air vortex at the center of the ring. The air vortex can be used to push down and interleave the flags into their final position at the ends of the jelly roll. After the flags are interleave in their proper position, as shown in FIG. 7A, a press with a stalk and a circular bottom can be used to bend the flags and press them down into their final position in a flower-shaped arrangement. In some embodiments, the press and directional air ring can be used simultaneously to bend and / or substantially interleave the flags.

[0061] As can be imagined by examining Figures 7A and 7B, the end of the jelly roll with the flags is inserted into the center of a directional air ring, and compressed air is forced at an angle through the central hole. The air creates a swirling vortex, which helps tilt, interleave, and pressurize the flags into their final flower shape by using air pressure to gently press each flag into place. In some embodiments, the directional air ring is configured to create a fluidized bed for the flags. It should be understood that the directional air ring is not limited to embodiments having a central hole or orifice that creates a pressurized vortex of air. In other embodiments, the central portion can include slits, channels, or other outlets for pressurized air, which create a pressurized air space useful for interleaving the flags within the jelly roll into their final shape.

[0062] In some embodiments, the flag of the electrode is pre-folded in-line (i.e., pre-wound) before winding the jelly roll. As shown in FIG. 8 , in some embodiments, the in-line folding is performed by a deflector that bends the flag in one direction as it approaches a roller. The roller can complete the folding so that the flag has a permanent crease, bend, or bend in relation to the foil portion of the electrode. In the embodiment shown in FIG. 9 , the flag is bent by moving across a roller and then contacting a wedge that presses the flag upward into a bent position relative to the foil electrode. In some embodiments, the in-line folding using a deflector also includes a mating surface against the deflector that forms a narrow channel through which the flag passes to form the bend. Of course, there are countless ways to fold the flag; these are just a few examples of how the flag can be folded before forming the jelly roll. In another example, shown in FIG. 10 , a press roller is positioned adjacent to an anvil roller, and the foil with the flag extends between the flags. The press roller bends the flag against the anvil roller as it passes through the roller set. It should be understood that other embodiments are contemplated, including two or more rollers, scoring spools, or combinations thereof.

[0063] In some embodiments, the folding rollers are pinch rollers, press rollers, or a combination thereof. In some embodiments, the rollers are configured to allow the flags to overhang the edges of the rollers. In some embodiments, the flags of the electrodes are folded in-line and further folded after winding of the electrodes to obtain their final interleaved flower shape.

[0064] As shown in FIG. 11A , during the winding process, the flags may be tensioned and / or bunched together to prevent them from interfering with each other and forming a regular, interleaved pattern of flags. Thus, in some embodiments, the flag positions of the unwound electrode sheet and / or wound electrode roll may be managed or manipulated by a flag management device, such as that shown in FIG. 11B , to form a substantially interleaved flag pattern in the final electrode roll. In some embodiments, the flag management device includes a mechanical deflector, an angled roller, a directed air device (e.g., a pressurized air nozzle), or a combination thereof. For example, when a transverse electrode is being wound into a jelly roll, the flag management device may move, move, pull, or push the flags toward the correct interleaved position within the jelly roll without tenting or clamping the flags at each end of the electrode.

[0065] In some embodiments, after the jelly roll is wrapped with folded flags, a second step is taken to complete the flags in their interleaved positions. In some embodiments, the second step utilizes a flag processing device. This post-winding flag processing may be performed by a mechanical deflector, a roller, a press, a directed air device (e.g., a directed air ring or air jet), or a combination thereof. In some embodiments, the roller is a continuous roller. In some embodiments, the press is selected from a flat-form press, a dome-form press, and combinations thereof.

[0066] Following formation of the electrode roll, remaining portions of the electrode sheet not used to form the electrode roll can be removed by cutting. In some embodiments, the cutting is performed by blade cutting, scissors cutting, laser cutting, or a combination thereof. After the first electrode roll is cut from the remaining electrode sheet, a second electrode roll can be formed from the remaining electrode sheet.

[0067] The electrode roll can be inspected to ensure that it meets manufacturing parameters such as electrode roll height and / or that the flags at each end of the roll are properly interleaved without tenting or clamping. In some embodiments, the folded flags are pressed against a clear glass or plastic window, and images are taken through the window of the pressed folded flags. FIG. 12 shows a schematic diagram of an inspection apparatus that can be used to inspect the electrode roll, including a press system with two glass plates, two image capture devices positioned on the outer surfaces of the glass plates, a press assembly, and a hard stop assembly configured to press the ends of the electrode roll using the two glass plates. In FIG. 12, the electrode roll is shown pressed between the two glass plates so that the image capture devices can capture images of the pressed flags of the anode and cathode of the electrode roll through the glass plates. The inspection apparatus of FIG. 12 also includes a jelly roll (JR) height measurement assembly used to measure the height of the electrode roll, as measured by the distance between the glass plates when pressed.

[0068] FIG. 13A shows a three-step process in which one end of a jelly roll is inspected by pressing the end against a glass plate, such as using the inspection apparatus of FIG. 12. As shown, a robotic arm or press is used to press the end of the roll toward the glass inspection plate. The end initially approaches the glass plate with the flags partially bent from a previous folding step during manufacturing. As the flags become more compressed and interleaved, the end continues to press against the glass plate. Finally, the end is fully pressed against the glass inspection plate, making the entire end flower structure available for imaging by an image capture and processing system.

[0069] It should be understood that the electrode roll has a flag formation at each end of the roll, with one end having a cathode flag and the other end having an anode flag. In some embodiments, during inspection, the roll can be pressed against two glass sheets and both ends simultaneously. In some embodiments, during inspection, the roll can be inspected at one end and then rotated to inspect the other end. In some embodiments, during inspection, the roll can be inspected at one end and then translated to another inspection station to inspect the other end.

[0070] The image processor can be fed an image of the fully compressed end of the roll and used to identify damaged, tensioned, and / or jammed flags. The image processor can look for dark spots that indicate clumps or damaged sets of flags. Figures 13B, 13C, and 13D show examples of improperly folded rolls, where bent or misshapen flags create discernible dark spots on the image. The image processor can look for flags that are bent outside the circumference of the jelly roll. The image processor can also look for other indications that the flags were not smoothly interleaved with one another, such as differences in light reflectance and different wavelengths, to determine if any winding errors have occurred. In one embodiment, the image processor can have machine learning capabilities that are trained to analyze properly folded and wound electrodes and generate weights and biases using deep learning, which helps it learn over time how to identify misfolded or damaged flags in a jelly roll. If a particular electrode fails inspection, an alarm, signal, or light can be activated to indicate that the electrode failed inspection.

[0071] Once the electrode roll is formed, it may be used to form an electrode storage device, such as a battery, or it may be packaged for storage and later used to form a battery. In some embodiments, the folded flag of the electrode roll is electrically connected to a current collector. In some embodiments, the flag may be connected to the current collector by a crimp, a solder joint, a weld, and combinations thereof. In some embodiments, the welding is performed by laser welding. In some embodiments, the electrode roll is placed in a housing and the housing is sealed. In some embodiments, an electrolyte is added to the housing.

[0072] The wound electrode manufacturing process is carried out at high speeds and / or in high volumes. In some embodiments, the electrode wrapping or winding process is carried out at a speed of about, at least, or at least about 0.5 m / s, 0.6 m / s, 0.7 m / s, 0.8 m / s, 0.9 m / s, 1 m / s, 1.2 m / s, 1.4 m / s, 1.6 m / s, 1.8 m / s, 2 m / s, 2.2 m / s, 2.4 m / s, 2.6 m / s, 2.8 m / s, 3 m / s, 3.5 m / s, 4 m / s, 5 m / s, or any value range therebetween. For example, in some embodiments, the electrode winding process is carried out at a speed of 1-3 m / s or about 1-3 m / s. In some embodiments, the high speed of the manufacturing process accurately results in wound electrodes with substantially interleaved flags.

[0073] In one exemplary process, an electrode having a foil is provided, and a slit is made in the foil to create a flag. The electrode is wound into a jelly roll electrode, and the remaining electrode film is cut from the rolled electrode. The straight flag of the cut wound electrode is folded and the flag position is controlled. The wound electrode is then inspected for flag defects.

[0074] In another exemplary process, an electrode having a foil is provided and slit to create a flag. The flag is folded in-line and the flag position is controlled just before winding, and then the electrode is wound into a jellyroll electrode. The remaining electrode film is cut from the wound electrode and inspected for flag defects.

[0075] After the roll with the interleaved flags is manufactured, the roll has anode and cathode current collectors welded, bonded, or otherwise electrically connected at each end, as described above with reference to Figures 5A-5C, to form a cartridge that can be placed in a can with electrolyte to form a lithium ion battery. In some embodiments, the interleaved flags are electrically connected directly to each end of the can.

[0076] The foregoing disclosure is not intended to limit the disclosure to the precise forms or embodiments disclosed herein. Accordingly, various alternative forms, embodiments, and / or modifications to the disclosure, whether expressly described or implied herein, are contemplated as possible in light of this disclosure. While embodiments of the disclosure have thus been described, those skilled in the art will recognize that changes can be made in form and detail without departing from the scope of the disclosure.

[0077] In the foregoing specification, the present disclosure has been described with reference to specific embodiments. However, as will be appreciated by those skilled in the art, the various embodiments disclosed herein can be modified or embodied in various other ways without departing from the spirit and scope of the present disclosure. Accordingly, this description should be considered illustrative and is for the purpose of teaching those skilled in the art how to make and use various embodiments of the disclosed battery system. It should be understood that the forms of the disclosure shown and described herein should be construed as representative embodiments. Equivalent elements or materials may be substituted for those typically shown and described herein. Furthermore, certain features of the present disclosure may be utilized independently of the use of other features, all of which will be apparent to those skilled in the art after having the benefit of this description of the present disclosure. The terms "including," "comprising," "incorporating," "consisting of," "having," "being," and the like, as used to describe and claim the present disclosure, are intended to be construed in a non-exclusive manner, i.e., allowing for the presence of items, components, or elements not expressly described. Also, references to the singular should be construed to relate to the plural as well.

[0078] Furthermore, the various embodiments disclosed herein should be construed in an illustrative and explanatory sense, and should not be construed as limiting the present disclosure in any way. All connection references (e.g., connected, associated, coupled, etc.) are used solely to aid the reader in understanding the present disclosure and do not create limitations with respect to the position, orientation, or use of any elements disclosed herein. Accordingly, any connection references should be interpreted broadly. Furthermore, such connection references do not necessarily indicate that two elements are directly connected to one another.

[0079] Furthermore, all numerical terms, such as, but not limited to, "first," "second," "1," "another," or any other conventional and / or numerical term, should also be construed as identifiers only to aid the reader's understanding of the various elements, embodiments, variations and / or modifications of the present disclosure, and in particular do not create any limitations regarding the order or priority of any element, embodiment, variation and / or modification relative to or over another element, embodiment, variation and / or modification.

[0080] It may be understood that one or more of the elements shown in the drawings / figures may also be implemented in a more separate or integrated manner, or may be removed in certain cases, as may be useful depending on the particular application.

Claims

1. 1. A method of manufacturing a tabless energy storage device, comprising: providing an electrode layer having an active material disposed over a foil; forming a series of flags on the foil to form a flagged electrode; winding the flagged electrode to form an electrode roll comprising a series of wound flags; and electrically connecting the wound flag to a current collector to form an energy storage device; The series of wrapped flags is in a substantially interleaved configuration, wherein the plurality of flags are interleaved in the substantially interleaved configuration with the trailing edge of one flag folded under the leading edge of an adjacent flag.

2. The method of claim 1 , wherein the flag is folded into a series of folded flags before winding the flagged electrode.

3. The method of claim 2 , wherein the folding is performed by a deflector, a roller, a scoring spool, or a combination thereof.

4. 3. The method of claim 2, wherein a flag management device moves the folded flags into the substantially interleaved configuration as the folded flags are rolled.

5. The method of claim 4 , wherein the flag management device comprises a diverter, a wheel, or an air nozzle.

6. The method of claim 1 , wherein after the flagged electrode is rolled, the flag is folded into a series of folded flags.

7. 7. The method of claim 6, wherein the folding is performed continuously.

8. 8. The method of claim 7, wherein the folding is performed by rollers, directed air devices, and combinations thereof.

9. 7. The method of claim 6, wherein the folding is performed simultaneously.

10. 10. The method of claim 9, wherein the folding is performed by a press, a directed air device, and combinations thereof.

11. 7. The method of claim 6, wherein a flag processor moves the folded flags into the substantially interleaved configuration.

12. The method of claim 11 , wherein the flag handling device comprises a mechanical deflector, a roller, a press, a directed air device, or a combination thereof.

13. 6. The method of claim 1, wherein the electrode layer comprises a first section used to form the electrode roll and a second section comprising a remaining portion of the electrode layer, the method further comprising cutting the first and second sections.

14. The method of claim 1 , further comprising inspecting the winding flag of the electrode roll.

15. The method according to any one of claims 1 to 5, wherein the electrode winding process is carried out at a speed of about 1 to 3 m / s.

16. 6. The method of claim 1, wherein the flags are exposed areas of the foil separated by slits.

17. The method according to claim 1 , wherein the flag is inclined towards or away from the winding direction of the electrode roll.

18. 1. A method for manufacturing a wound electrode, comprising: providing an electrode layer comprising an active material disposed over a foil; forming a series of flags on the foil to form a flagged electrode; winding the flagged electrode to form an electrode roll comprising a series of wound flags; and folding the folded flag to form a folded folded flag, wherein each flag of the folded flag is oriented into a substantially interleaved configuration; The series of wrapped flags is in a substantially interleaved configuration, wherein the plurality of flags are interleaved in the substantially interleaved configuration with the trailing edge of one flag folded under the leading edge of an adjacent flag.

19. 1. A method for manufacturing a wound electrode, comprising: providing an electrode layer comprising an active material disposed over a foil; forming a series of flags on the foil to form a flagged electrode; folding the flag to create a folded flag electrode comprising a series of folded flags; and winding the folded flagged electrode to form an electrode roll, wherein as the folded flags are wound, each flag of the folded flags is oriented into a substantially interleaved configuration, wherein a plurality of flags are interleaved and the trailing edge of one flag is folded under the leading edge of an adjacent flag.

20. An interleaved flagged electrode, comprising: a wound flagged electrode layer comprising an active material disposed over the foil; the foil comprises a series of flags; each of the series of flags being folded into a substantially interleaved configuration; In the substantially interleaved configuration, the flags are interleaved with the trailing edge of one flag folded under the leading edge of an adjacent flag.

21. The active material may be a silicon material, a graphite material, graphite, a graphene-containing material, hard carbon, soft carbon, carbon nanotubes, porous carbon, conductive carbon, lithium nickel manganese cobalt oxide (NMC), lithium manganese oxide (LMO), lithium iron phosphate (LFP), lithium cobalt oxide (LCO), lithium titanate (LTO), lithium nickel cobalt aluminum oxide (NCA), layered transition metal oxides (e.g., LiCoO ２ (LCO), Li(NiMnCo)O ２ (NMC) and / or LiNi ０．８ Co ０．１５ Al ０．０５ O ２ (NCA)), spinel manganese oxide (LiMn ２ O ４ (LMO) and / or LiMn １．５ Ni ０．５ O ４ (LMNO), olivine (e.g., LiFePO ４ ), chalcogenides (LiTiS ２ ), Tavorite (LiFeSO ４ F), silicon, silicon oxide (SiOx), aluminum, tin, tin oxide (SnOx), manganese oxide (MnOx), molybdenum oxide (MoO ２ ), molybdenum disulfide (MoS ２ ), nickel oxide (NiOx), copper oxide (CuOx), and lithium sulfide (Li ２ 21. The electrode of claim 20, wherein the electrode is selected from the group consisting of:

22. 21. The electrode of claim 20, wherein the flag is square or trapezoidal in shape.

23. 21. The electrode of claim 20, wherein the flag is angled between 5 and 10 degrees, between 11 and 20 degrees, between 21 and 30 degrees, or between 10 and 15 degrees.

24. 21. The electrode of claim 20, wherein each of the flags is 1 to 10 mm in height.

25. 21. The electrode of claim 20, wherein each of the flags is 1 to 10 mm wide.

26. 21. The electrode of claim 20, wherein the series of flags are formed from copper or aluminum.

27. 27. An electrode according to any one of claims 20 to 26, mounted inside a can with a lid.

28. 28. The electrode of claim 27, wherein the series of flags are in electrical communication with the lid of the can.

29. 27. The electrode of any one of claims 20 to 26, wherein the electrode is wound into a jelly roll.

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