Fluorine-rich organic / inorganic coatings for lithium-rich manganese materials

Abstract

Aspects of the present disclosure include lithium-rich manganese (LMR) battery cells having fluorine-rich organic / inorganic coatings and methods of making the same. An example vehicle includes an electric motor and a battery pack electrically coupled to the electric motor. The battery pack includes a battery cell including an anode current collector, an anode active material layer in direct contact with a surface of the anode current collector, a cathode current collector, a cathode active material layer in direct contact with a surface of the cathode current collector, and a separator. The cathode active material layer includes a lithium manganese rich (LMR) cathode active material coated with a fluorine rich organic / inorganic coating. The fluorine rich organic / inorganic coating includes carbon nanotube (CNT) filled polytetrafluoroethylene (PTFE) nanofibers that are physically adsorbed onto the LMR cathode active material.

Description

Technical Field

[0001] This disclosure relates to the manufacture of battery cells, and more specifically to the use of fluorine-rich organic / inorganic coatings for lithium and manganese-rich (LMR) materials. Background Technology

[0002] Lithium-ion batteries (also known as lithium-ion battery cells) are a type of rechargeable battery technology that has gained significant attention due to their relatively high energy density and long cycle life compared to other battery chemistry. The anode (negative electrode) in a lithium-ion battery is typically made of graphite, a carbon-based material that allows for the reversible intercalation and decaling of lithium ions. The cathode (positive electrode) can be made of various lithium-containing compounds, such as lithium transition metal oxides (e.g., LiCoO2, LiNiMnCoO2, etc.), lithium metal phosphates (e.g., LiFePO4), or other suitable materials that allow for the reversible intercalation and decaling of lithium ions.

[0003] In a lithium-ion battery cell, the electrodes are separated by an electrolyte, which is typically a lithium salt dissolved in an organic solvent, solid polymer, or solid electrolyte. The electrolyte acts as the medium for lithium-ion transport between the anode and cathode during charging and discharging. Current collectors provide a conductive path for electrons to flow between the electrodes and external circuitry. Current collectors for the anode are typically made of copper or copper alloys, while current collectors for the cathode are typically made of aluminum or aluminum alloys.

[0004] During discharge, lithium ions are deintercalated from the anode and migrate through the electrolyte to intercalate into the cathode material, while electrons flow through the external circuitry to power the device. During charging, this process is reversed, with lithium ions being extracted from the cathode and intercalated into the anode. Summary of the Invention

[0005] In one exemplary embodiment, the vehicle includes an electric motor and a battery pack electrically connected to the electric motor. The battery pack includes battery cells, each battery cell comprising an anode current collector, an anode active material layer in direct contact with the surface of the anode current collector, a cathode current collector, a cathode active material layer in direct contact with the surface of the cathode current collector, and a separator. The cathode active material layer comprises lithium-rich manganese (LMR) cathode active material coated with a fluorine-rich organic / inorganic coating. The fluorine-rich organic / inorganic coating comprises polytetrafluoroethylene (PTFE) nanofibers filled with carbon nanotubes (CNTs) physically adsorbed onto the LMR cathode active material.

[0006] In addition to one or more features described herein, in some embodiments, the LMR cathode active material comprises nickel in a nickel-manganese molar ratio of 30:70 to 80:20.

[0007] In some embodiments, the LMR cathode active material comprises a lithium to transition metal molar ratio of 1.06 to 1.60.

[0008] In some embodiments, the LMR cathode active material comprises CNTs to PTFE in a weight ratio of 2.0% to 5.0% by weight of CNTs.

[0009] In some embodiments, the LMR cathode active material comprises CNT / PTFE in a weight ratio of 0.5% to 10.0% by weight of CNT / PTFE.

[0010] In some embodiments, the LMR cathode active material comprises 0.1 to 1.0% by weight of alumina.

[0011] In some embodiments, the weight ratio of LMR cathode active material in the cathode active material layer is 80% to 99% by weight.

[0012] In another exemplary embodiment, the battery cell includes an anode current collector, an anode active material layer in direct contact with the surface of the anode current collector, a cathode current collector, a cathode active material layer in direct contact with the surface of the cathode current collector, and a separator. The cathode active material layer includes lithium-rich manganese (LMR) cathode active material coated with a fluorine-rich organic / inorganic coating. The fluorine-rich organic / inorganic coating includes polytetrafluoroethylene (PTFE) nanofibers filled with carbon nanotubes (CNTs) physically adsorbed onto the LMR cathode active material.

[0013] In some embodiments, the LMR cathode active material comprises nickel with a nickel-to-manganese molar ratio of 30:70 to 80:20.

[0014] In some embodiments, the LMR cathode active material comprises a lithium to transition metal molar ratio of 1.06 to 1.60.

[0015] In some embodiments, the LMR cathode active material comprises CNTs to PTFE in a weight ratio of 2.0% to 5.0% by weight of CNTs.

[0016] In some embodiments, the LMR cathode active material comprises CNT / PTFE in a weight ratio of 0.5% to 10.0% by weight of CNT / PTFE.

[0017] In some embodiments, the LMR cathode active material comprises 0.1 to 1.0% by weight of alumina.

[0018] In some embodiments, the weight ratio of LMR cathode active material in the cathode active material layer is 80% to 99% by weight.

[0019] In yet another exemplary embodiment, a method may include forming an anode current collector, an anode active material layer in direct contact with the surface of the anode current collector, a cathode current collector, a cathode active material layer in direct contact with the surface of the cathode current collector, and a separator. The cathode active material layer comprises a lithium-rich manganese (LMR) cathode active material coated with a fluorine-rich organic / inorganic coating. The fluorine-rich organic / inorganic coating comprises polytetrafluoroethylene (PTFE) nanofibers filled with carbon nanotubes (CNTs) physically adsorbed onto the LMR cathode active material.

[0020] In some embodiments, the LMR cathode active material comprises nickel with a nickel-to-manganese molar ratio of 30:70 to 80:20.

[0021] In some embodiments, the LMR cathode active material comprises a lithium to transition metal molar ratio of 1.06 to 1.60.

[0022] In some embodiments, the LMR cathode active material comprises CNTs to PTFE in a weight ratio of 2.0% to 5.0% by weight of CNTs.

[0023] In some embodiments, the LMR cathode active material comprises CNT / PTFE in a weight ratio of 0.5% to 10.0% by weight of CNT / PTFE.

[0024] In some embodiments, the LMR cathode active material comprises 0.1 to 1.0% by weight of alumina.

[0025] In some embodiments, the weight ratio of LMR cathode active material in the cathode active material layer is 80% to 99% by weight.

[0026] The above-described features and advantages, as well as other features and advantages of this disclosure, will become apparent when taken in conjunction with the accompanying drawings and the following detailed description. Attached Figure Description

[0027] Other features, advantages, and details appear by way of example only in the following detailed embodiments, which are described in conjunction with the accompanying drawings.

[0028] Figure 1 It is a vehicle configured according to one or more embodiments;

[0029] Figure 2A This is an example battery cell according to one or more embodiments;

[0030] Figure 2B According to one or more embodiments Figure 2A A detailed view of the battery cell shown;

[0031] Figure 3The manufacturing process of a lithium-rich manganese (LMR) material coated with carbon nanotube-filled polytetrafluoroethylene (PTFE) nanofibers is described in one or more embodiments.

[0032] Figure 4 The manufacturing process of LMR material coated with PTFE nanofibers filled with carbon nanotubes, according to one or more embodiments;

[0033] Figure 5 This is a manufacturing process for LMR materials coated with PTFE nanofibers filled with carbon nanotubes, according to one or more embodiments; and

[0034] Figure 6 It is a flowchart according to one or more embodiments. Detailed Implementation

[0035] The following description is exemplary in nature only and is not intended to limit this disclosure, its application, or use. It should be understood that throughout the drawings, corresponding reference numerals denote the same or corresponding parts and features.

[0036] The increasing demand for energy storage systems that offer higher energy density, faster charging, and extended operational life, driven in part by the surge in electric vehicles, poses significant challenges to the materials used in battery cell components. Research and development efforts continue to identify novel materials and manufacturing technologies that can meet the growing demands for battery cells and other energy storage systems.

[0037] Lithium-rich manganese (LMR) materials are promising candidates for next-generation lithium-ion battery cathodes due to their high energy density and potential for improved performance. These materials are typically denoted as xLi₂MnO. 3(1-x) LiMO2 (where M = Ni, Co, Mn, etc.) offers several advantages that make it attractive to researchers and battery manufacturers. For example, LMR cathodes can provide significantly higher capacities compared to conventional lithium-ion battery cathodes. Theoretical capacities exceeding 250 mAh / g have been reported, significantly higher than existing lithium-ion cathodes. Other advantages, such as the abundance of manganese and reduced dependence on cobalt, make LMR materials ideal for large-scale production. Despite the promising properties of LMR materials, they face several challenges that hinder their widespread commercial adoption. Perhaps most notably, LMR materials typically require cycling (activation, charging) at relatively high voltages (i.e., at least 4.4 to 4.6 mAh) to realize their high capacity benefits. Unfortunately, more side reactions occur at such high voltages, which can lead to capacity decay, excess electrolyte usage, and gassing problems.

[0038] This disclosure describes a lithium-ion battery and a method for manufacturing the same, which utilizes a fluorine-rich organic / inorganic coating on a lithium-rich manganese (LMR) material. Specifically, three novel composite coatings are described herein. In the first composite coating, polytetrafluoroethylene (PTFE) nanofibers are filled with carbon nanotubes (CNTs). The PTFE / CNT composite material is mixed with the LMR cathode active material to form an LMR coated with carbon-filled PTFE nanotubes via physical adsorption. In the second composite coating, a calcination step is introduced after the formation of the carbon-filled PTFE nanotube-coated LMR. The result is the formation of a fluorine-rich carbon coating on the LMR. In the third composite coating, an alumina precursor is included in a mixture of the PTFE / CNT composite and the LMR cathode active material, and a calcination step is introduced after shear mixing or spring drying of the resulting composite. The result is the formation of a fluorine-doped alumina-carbon coating. Advantageously, the fluorine-rich organic / inorganic coatings described herein can function as a protective layer, mitigating side reactions during high-voltage LMR cycling.

[0039] According to an exemplary embodiment, the vehicle is Figure 1 The vehicle 100 is generally indicated by 100. The vehicle 100 is shown in the form of an automobile having a body 102. The body 102 includes a passenger compartment 104, within which a steering wheel, front seats, and rear passenger seats (not shown separately) are arranged. Several components are arranged within the body 102, including, for example, an electric motor 106 (shown by a projection below the front hood). The electric motor 106 is shown only for ease of illustration and discussion. It should be understood that the configuration, location, size, arrangement, etc., of the electric motor 106 are not intended to be particularly limited, and all such configurations (including multi-motor configurations) are within the scope of this disclosure.

[0040] The electric motor 106 is powered via a battery pack 108 (shown in projection near the rear of the vehicle 100). The battery pack 108 is shown for ease of illustration and discussion only. It should be understood that the configuration, location, size, arrangement, etc., of the battery pack 108 are not intended to be particularly limited, and all such configurations (including split configurations) are within the scope of this disclosure. Furthermore, although this disclosure is discussed primarily in the context of the battery pack 108 configured for the electric motor 106 of the vehicle 100, the aspects described herein can be similarly incorporated into any system (vehicle, building, or otherwise) having an energy storage system (e.g., one or more battery packs or modules), and all such configurations and applications are within the scope of this disclosure.

[0041] As will be detailed herein, the battery pack 108 includes one or more battery modules, battery cells and / or battery pouches (collectively, “battery cells”) having lithium-ion batteries based on lithium-rich manganese (LMR) having fluorine-rich organic / inorganic coatings. Figure 2A An example battery cell is shown in the image. Figure 2B It shows Figure 2A A detailed view of the battery cells. (For...) Figure 3 , Figure 4 and Figure 5 Three novel composite coatings are described.

[0042] Figure 2A An example battery cell 202 according to one or more embodiments is shown. The battery cell 202 can be incorporated into a battery pack (e.g., Figure 1 One of the multiple battery cells in the battery pack 108. Figure 2B An illustration is provided according to one or more embodiments. Figure 2A Detailed view 204 of the battery cell 202 shown. (See attached image.) Figure 2B As shown, the battery cell 202 includes, from left to right, an anode current collector 206, an anode active material layer 208, a separator 210, a cathode active material layer 212, and a cathode current collector 214, which are configured and arranged as shown in the figure.

[0043] The anode current collector 206 and the cathode current collector 214 can be made of sheets, foils (continuous or perforated or slitted), or meshes of conductive material. For example, the cathode current collector 214 can be made of aluminum foil, stainless steel, and / or titanium foil. Other materials are possible, such as half-metals (e.g., tin, graphite) and alloys of metals and / or their half-metals. In some embodiments, the cathode current collector 214 is made of aluminum foil. The anode current collector 206 may include, for example, copper foil and / or one or more graphene layers. In some embodiments, the anode current collector 206 is made of copper foil. The thickness of the current collector can be approximately 10 to 20 μm, but other thicknesses are also within the scope of this disclosure.

[0044] The anode active material layer 208 is not particularly limited and may include, for example, lithium metal, activated carbon powder, graphite, silicon, silicon-graphite composites, tin, tin oxide (SnO2), tin-cobalt alloys, and lithium titanate (Li4Ti5O2). 12 LTO and its combinations.

[0045] For example, targeting Figure 3 , Figure 4 and Figure 5In more detail, the cathode active material layer 212 may comprise a lithium-rich manganese (LMR) cathode material having a fluorine-rich organic / inorganic coating. In some embodiments, the LMR cathode material may comprise nickel and manganese in a molar ratio of 30:70 to 80:20. In some embodiments, the cathode active material layer 212 may also comprise Co in the range of 0% to 20%. In some embodiments, the LMR cathode material may comprise lithium and a transition metal in a molar ratio of 1.06 to 1.60. In some embodiments, the cathode active material layer 212 comprises an LMR cathode material coated with carbon nanotube-filled PTFE nanofibers (see [link to documentation]). Figure 3 In some embodiments, the CNT / PTFE ratio may be in the range of 2 to 5% by weight of CNT. The composite CNT / PTFE-LMR weight ratio may be in the range of 0.5 to 10% by weight of CNT / PTFE.

[0046] In some embodiments, the LMR cathode material may include, for example, lithium-rich manganese oxide (LMR), lithium manganese oxide (LMO), and lithium nickel manganese oxide (LNMO). Other materials include nickel manganese cobalt (NMC) variants, such as NMC 622, NMC 811, and NMC 532. These materials are part of layered oxide cathodes and can be modified to produce an LMR-type structure. Other options include lithium nickel manganese spinel (LNMO) and lithium-rich manganese-rich layered NMC materials (LMR-NMC). While not intended to be particularly limiting, the weight percentage of coated LMR in the cathode active material layer 212 can be between 80% and 99% (by weight).

[0047] Depending on the battery construction (e.g., conventional current collector versus bipolar current collector), separator 210 is optional, but if included, separator 210 can be positioned to separate the anode active material layer 208 and the cathode active material layer 212. Separator 210 may include dielectric materials such as polyethylene (PE), polypropylene (PP), polyethylene terephthalate (PET), synthetic fluoropolymers (e.g., polytetrafluoroethylene (PTFE)) and their composites, but other dielectrics are also within the scope of this disclosure. In some embodiments, separator 210 may include a thermally stable coating to improve shrinkage behavior (e.g., a porous ceramic coating or a porous ester-type polymer coating, including, for example, polyimide, polyamide, polyimide-polyamide (PI / PA) copolymer, etc.). The thickness of separator 210 may be approximately 12 μm to 16 μm, but other thicknesses are also within the scope of this disclosure.

[0048] like Figure 2BAs further shown, battery cell 202 includes electrolyte 216. Electrolyte 216 may include liquid electrolyte, solid electrolyte, and / or polymer electrolyte. In some embodiments, electrolyte 216 is a liquid electrolyte that permeates, covers, and / or permeates cathode active material layer 212 (as shown). In some embodiments, the liquid electrolyte partially permeates separator 210 (as shown). In some embodiments, electrolyte 216 includes a lithium salt dissolved in a solvent, but other liquid electrolytes are also possible, and all such configurations are within the scope of this disclosure. The lithium salt selected for electrolyte 216 is not intended to be particularly limited and may vary depending on the needs of a given application. In some embodiments, for example, lithium salts include lithium hexafluorophosphate (LiPF6), lithium bis(trifluoromethanesulfonyl)imide (LiTFSI), lithium bis(oxalate)borate (LiBOB), lithium difluoro(oxalate)borate (LiDFOB), lithium bis(fluorosulfonyl)imide (LiFSI), lithium trifluoromethanesulfonate (LiTf), lithium tetrafluoroborate (LiBF4), lithium nitrate (LiNO3), and / or lithium bis(pentafluoroethanesulfonyl)imide (LiBETI) and combinations thereof.

[0049] The concentration of one or more lithium salts in electrolyte 216 will vary depending on the selected lithium salt (one or more) and the needs of a given application. The lithium salt concentration can be varied, for example, to target a predetermined ionic conductivity (increasing the salt concentration causes the ionic conductivity to increase to a point beyond which the conductivity decreases due to increased ion-ion interactions and viscosity), to provide suitable levels of salt dissociation and ion mobility (for a given lithium salt, there exists a minimum threshold concentration below which the salt may not completely dissociate, resulting in a lack of charge carriers; conversely, there exists a maximum threshold concentration above which increased ion-ion interactions sufficiently impede ion mobility to reduce conductivity), to provide a target electrolyte viscosity, to target a predetermined electrochemical stability window, and / or to influence the formation and composition of the SEI layer on the lithium metal anode. In some embodiments, the lithium salt can be formed at a concentration of 0.1 M to 2 M, for example, 0.8 M, but other concentrations are also within the scope of this disclosure.

[0050] Figure 3 The following are illustrated, according to one or more embodiments, for coating LMR materials with PTFE nanofibers filled with carbon nanotubes (e.g., Figure 2B The manufacturing process 300 for the cathode active material in the cathode active material layer 212. For example... Figure 3 As shown, manufacturing process 300 includes steps 302, 304 and 306, which are configured and arranged as shown in the figure.

[0051] In some embodiments, step 302 includes forming or otherwise providing an LMR-type cathode active material (LMRCAM) 350 and carbon nanotube-filled PTFE nanofibers 352. The LMRCAM 350 may be formed from a lithium-manganese-rich cathode material, such as those previously used for… Figure 2B The carbon nanotube-filled PTFE nanofibers 352 may include a PTFE nanofiber membrane 354 filled with carbon nanotubes 356.

[0052] In some embodiments, the carbon nanotube-filled PTFE nanofibers 352 can be formed, as needed, from polyethylene oxide (PEO) (also known as polyethylene glycol (PEG)) and a series of CNT aqueous dispersions with varying contents. For example, 0.409 g of PEO can be mixed with a CNT aqueous dispersion having a CNT content relative to PTFE of 0.1, 0.5, 1.0, 3.0, and 5.0% by weight. The PEO and CNT aqueous dispersions can be mixed using suitable processing conditions. For example, the PEO and CNT aqueous dispersions can be mixed by magnetic stirring at 40°C for 3 hours. After mixing, a PTFE emulsion can be added. Continuing with the previous examples, 5.0 g of PTFE emulsion (PTFE 60% by weight) can be added to the mixed PEO / CNT solution by magnetic stirring for 6 hours. After introducing PTFE, the resulting PTFE / PEO / CNT nanofiber membrane can be electrospinned at 20°C, for example, at a supply rate of 1 mL / h, a voltage of 15 kV, and an atmospheric pressure of 0.1 MPa. The collection distance can be set as needed, for example, 13 cm. The resulting PTFE / PEO / CNT precursor can be collected and dried, for example, at 60°C for 12 hours. Finally, the dried PTFE / PEO / CNT precursor can be sintered at, for example, 380°C to obtain carbon nanotube-filled PTFE nanofibers 352. It was observed that the weight percentage of CNTs in the carbon nanotube-filled PTFE nanofibers 352 will vary depending on the CNT content of the CNT aqueous dispersion used in step 302 (e.g., 3% by weight, etc.).

[0053] In some embodiments, step 304 includes coating the LMRCAM 350 with carbon nanotube-filled PTFE nanofibers 352. The LMR CAM 350 can be coated with the carbon nanotube-filled PTFE nanofibers 352 using any suitable method, such as shear mixing 360, dry mixing (not shown separately), wet coating (not shown separately), and / or spray drying 362. It should be understood that the specific conditions used for mixing and / or drying will vary depending on the given application. For example, a spray drying process may have a powder concentration of 1 g / 30 mL in solution, a nozzle cleaner frequency of 0.2 Hz, a drying air flow rate of 30 L / min, a drying gas temperature of 140 °C, and a sample-to-nozzle flow rate of 5 cc / min. In some embodiments, the carbon nanotube-filled PTFE nanofibers 352 are physically adsorbed onto the surface of the LMR CAM 350, thereby forming a fluorine-rich organic / inorganic coating 358 by physical adsorption.

[0054] In some embodiments, step 306 includes completing the electrode fabrication process using the fluorine-rich organic / inorganic coating 358 obtained in step 304. While not intended to be particularly limiting, step 306 may include forming a completed cathode active material layer (e.g., using LMR CAM 350 and the fluorine-rich organic / inorganic coating 358) Figure 2B The cathode active material layer 212 in the battery cell 202 comprises an LMR material with a nickel / manganese molar ratio of 30:70 to 80:20, a lithium / transition metal molar ratio of 1.06 to 1.60, a CNT / PTFE ratio of 2.0 to 5.0% by weight of CNT, and a CNT / PTFE ratio of 0.5 to 10.0% by weight of CNT / PTFE. In some embodiments, the cathode active material layer 212 may also include Co in the range of 0% to 20%. Step 306 may also include forming a battery cell (e.g., Figure 2B Any other components and / or sub-components of the battery cell 202 shown, such as forming the anode current collector 206, the anode active material layer 208, the separator 210, and the cathode current collector 214. Advantageously, when cycled at relatively high LMR cycling voltages (e.g., 4.4V to 4.6V), the fluorine-rich organic / inorganic coating 358 mitigates side reactions at the cathode-electrolyte interface in the battery cell 202.

[0055] Figure 4 The following are illustrations of coating LMR materials with PTFE nanofibers filled with carbon nanotubes (e.g., according to one or more embodiments). Figure 2B The manufacturing process 400 is similar to that for the cathode active material in the cathode active material layer 212. Figure 3The manufacturing process discussed is 300, but manufacturing process 400 introduces a calcination step after coating LMR CAM 350 with PTFE nanofibers 352 filled with carbon nanotubes (see [link]). Figure 3 Step 304). For example... Figure 4 As shown, manufacturing process 400 includes steps 402, 404, 406 and 408, which are configured and arranged as shown in the figure.

[0056] In some embodiments, step 402 includes using a method for targeting Figure 3 The LMR-type cathode active material (LMR CAM) 350 and carbon nanotube-filled PTFE nanofibers 352 are formed or otherwise provided in a manner similar to that discussed in step 302. The LMR CAM 350 can be formed from lithium-rich manganese cathode materials, such as those previously described for... Figure 2B The carbon nanotube-filled PTFE nanofibers 352 may include a PTFE nanofiber membrane 354 filled with carbon nanotubes 356.

[0057] In some embodiments, step 404 includes coating LMR CAM350 with PTFE nanofibers 352 filled with carbon nanotubes, thereby achieving a coating with a specific purpose. Figure 3 Step 304 discusses a similar method for forming a fluorine-rich organic / inorganic coating 358.

[0058] In some embodiments, step 406 includes calcining the fluorine-rich organic / inorganic coating 358 obtained in step 404 to obtain a fluorine-doped carbon coating 450. In some embodiments, step 406 includes calcination at a temperature of 600 degrees Celsius, but other temperatures are also within the range of considerations in this disclosure. In some embodiments, step 406 includes a calcination period of 6 to 12 hours (e.g., 8 hours) at a temperature of 500 to 800 degrees Celsius under an inert carrier gas.

[0059] In some embodiments, step 408 includes completing the electrode fabrication process using the fluorine-doped carbon coating 450 obtained in step 406. While not intended to be particularly limiting, step 408 may include forming a final cathode active material layer using LMR CAM 350 and the fluorine-doped carbon coating 450 (e.g., Figure 2B The cathode active material layer 212 in the battery cell 202 comprises an LMR material having a nickel / manganese molar ratio of 30:70 to 80:20, a lithium / transition metal molar ratio of 1.06 to 1.60, a CNT / PTFE ratio of 2.0 to 5.0% by weight of CNT, and a CNT / PTFE ratio of 0.5 to 10.0% by weight of CNT / PTFE. Step 408 may also include forming a battery cell (e.g., Figure 2BAny other component and / or sub-component of the battery cell 202 shown, for example, forming an anode current collector 206, an anode active material layer 208, a separator 210, and a cathode current collector 214.

[0060] Figure 5 The following are illustrations of coating LMR materials with PTFE nanofibers filled with carbon nanotubes (e.g., according to one or more embodiments). Figure 2B The manufacturing process 500 is similar to that for the cathode active material in the cathode active material layer 212. Figure 4 The manufacturing process discussed is 400, but manufacturing process 500 introduces an alumina precursor 550 before coating LMR CAM 350 with carbon nanotube-filled PTFE nanofibers 352 (see [link]). Figure 4 Step 404). For example... Figure 5 As shown, manufacturing process 500 includes steps 502, 504, 506 and 508, which are configured and arranged as shown in the figure.

[0061] In some embodiments, step 502 includes using a method for targeting Figure 3 Step 302 and Figure 4 The LMR-type cathode active material (LMR CAM) 350 and carbon nanotube-filled PTFE nanofibers 352 are formed or otherwise provided in a manner similar to that discussed in step 402. The LMR CAM 350 can be formed from lithium-rich manganese cathode materials, such as those previously described for... Figure 2B The carbon nanotube-filled PTFE nanofibers 352 may include a PTFE nanofiber membrane 354 filled with carbon nanotubes 356. However, unlike manufacturing methods 300 and 400, step 502 additionally includes forming or otherwise providing an alumina precursor 550. In some embodiments, the alumina precursor 550 includes one or more of lithium aluminate, colloidal alumina, alumina, aluminum nitrate, aluminum hydroxide, aluminum isopropoxide, and aluminum sulfate.

[0062] In some embodiments, step 504 includes coating LMR CAM 350 with carbon nanotube-filled PTFE nanofibers 352 and alumina precursor 550 to form a fluorine-rich organic / inorganic alumina coating 552. In some embodiments, the alumina precursor 550 is combined with LMR CAM 350 and carbon nanotube-filled PTFE nanofibers 352 in a weight ratio of 0.1% to 1.0% by weight.

[0063] In some embodiments, step 506 includes calcining the fluorine-rich organic / inorganic alumina coating 552 obtained in step 504 to obtain a fluorine-doped alumina-carbon coating 554. In some embodiments, step 506 includes calcination at a temperature of 600 degrees Celsius, but other temperatures are also within the range of considerations in this disclosure. In some embodiments, step 506 includes calcination at a temperature of 500 to 800 degrees Celsius under an inert carrier gas.

[0064] In some embodiments, step 508 includes completing the electrode fabrication process using the fluorine-doped alumina-carbon coating 554 obtained in step 506. While not intended to be particularly limiting, step 508 may include forming the final cathode active material layer using LMR CAM 350 and the fluorine-doped alumina-carbon coating 554 (e.g., Figure 2B The cathode active material layer 212 in the battery cell 202 comprises an LMR material of LiAlO2 (alumina) with a nickel / manganese molar ratio of 30:70 to 80:20, a lithium / transition metal molar ratio of 1.06 to 1.60, a CNT / PTFE ratio of 2.0 to 5.0% by weight of CNT, a CNT / PTFE ratio of 0.5 to 10.0% by weight of CNT / PTFE, and a CNT / PTFE ratio of 0.1 to 1.0% by weight. Step 508 may also include forming a battery cell (e.g., Figure 2B Any other components and / or sub-components of the battery cell 202 shown, such as forming the anode current collector 206, the anode active material layer 208, the separator 210, and the cathode current collector 214. Advantageously, the integration of the alumina precursor 550 within the fluorine-doped alumina-carbon coating 554 provides a robust organic / inorganic interface and can enhance conductivity and improve the cycle stability of the battery cell 202.

[0065] Now for reference Figure 6 According to one embodiment, a flowchart 600 for providing a fluorine-rich organic / inorganic coating for lithium-rich manganese (LMR) materials is generally shown. (Reference) Figure 1-5 Describe flowchart 600, and flowchart 600 may include Figure 6 Additional steps not depicted. Although depicted in a specific order, Figure 6 The boxes depicted in the text can be rearranged, subdivided, and / or combined.

[0066] At frame 602, the method includes forming an anode current collector.

[0067] At frame 604, the method includes forming an anolyte active material layer in direct contact with the surface of the anode current collector.

[0068] At frame 606, the method includes forming a cathode current collector.

[0069] At block 608, the method includes forming a cathode active material layer in direct contact with the surface of the cathode current collector. In some embodiments, the cathode active material layer comprises an LMR cathode active material coated with a fluorine-rich organic / inorganic coating. In some embodiments, the fluorine-rich organic / inorganic coating comprises polytetrafluoroethylene nanofibers filled with carbon nanotubes physically adsorbed onto the LMR cathode active material.

[0070] At block 610, the method includes forming a spacer located between the anode active material layer and the cathode active material layer.

[0071] In some embodiments, the LMR cathode active material comprises nickel in a nickel-to-manganese molar ratio of 30:70 to 80:20. In some embodiments, the cathode active material layer 212 may also include Co in the range of 0% to 20%.

[0072] In some embodiments, the LMR cathode active material comprises a lithium to transition metal molar ratio of 1.06 to 1.60.

[0073] In some embodiments, the LMR cathode active material comprises CNTs to PTFE in a weight ratio of 2.0% to 5.0% by weight of CNTs.

[0074] In some embodiments, the LMR cathode active material comprises CNT / PTFE in a weight ratio of 0.5% to 10.0% by weight of CNT / PTFE.

[0075] In some embodiments, the LMR cathode active material comprises 0.1% to 1.0% by weight of alumina, and wherein the LMR cathode active material in the cathode active material layer comprises 80% to 99% by weight.

[0076] The term “a” does not indicate a limitation of quantity, but rather that at least one of the referenced items is present. Unless the context clearly indicates otherwise, the term “or” means “and / or”. Throughout the specification, reference to “aspect” means that a particular element described in connection with that aspect (e.g., a feature, structure, step, or characteristic) is included in at least one aspect described herein and may or may not be present in other aspects. Furthermore, it should be understood that the described elements may be combined in any suitable manner in the aspects.

[0077] Furthermore, as used in this disclosure, phrases such as "at least one of A, B, or C" or "at least one of A, B, and C" should be interpreted as selecting at least one from the group including "A, B, and C". Unless explicitly stated otherwise in connection with specific instances of this disclosure, this phrasing does not imply "at least one of A, at least one of B, and at least one of C". As used in this disclosure, the example "at least one of A, B, or C" would cover any of the following selections: {A}, {B}, {C}, {A, B}, {A, C}, {B, C}, and {A, B, C}.

[0078] When an element, such as a layer, film, region, or substrate, is referred to as being “on” another element, it can be directly on the other element, or there may be intermediate elements present. Conversely, when an element is referred to as being “directly” on another element, there are no intermediate elements present.

[0079] Unless otherwise stated herein, all test standards are the most recent standards in effect as of the date of filing of this application, or, if priority is claimed, the date of filing of the earliest priority application in which a test standard appears.

[0080] Unless otherwise defined, the technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure pertains.

[0081] While the foregoing disclosure has been described with reference to exemplary embodiments, those skilled in the art will understand that various changes can be made and elements can be substituted with equivalents without departing from its scope. Furthermore, many modifications can be made to adapt particular situations or materials to the teachings of this disclosure without departing from the basic scope of this disclosure. Therefore, it is intended that this disclosure be limited to the specific embodiments disclosed, but will include all embodiments falling within its scope.

Claims

1. A vehicle comprising: Electric motor; as well as A battery pack, connected to the electric motor, the battery pack comprising a plurality of battery cells, each of the plurality of battery cells comprising: Anode current collector; The anolyte active material layer is in direct contact with the surface of the anolyte current collector; Cathode current collector; A cathode active material layer, in direct contact with the surface of the cathode current collector, comprises a lithium-rich manganese (LMR) cathode active material coated with a fluorine-rich organic / inorganic coating; and A separator is positioned between the anode active material layer and the cathode active material layer; The fluorine-rich organic / inorganic coating comprises polytetrafluoroethylene (PTFE) nanofibers filled with carbon nanotubes (CNTs) physically adsorbed onto the LMR cathode active material.

2. The vehicle according to claim 1, wherein the LMR cathode active material comprises nickel with a nickel to manganese molar ratio of 30:70 to 80:

20.

3. The vehicle according to claim 1, wherein the LMR cathode active material comprises a lithium to transition metal molar ratio of 1.06 to 1.

60.

4. The vehicle according to claim 1, wherein the LMR cathode active material comprises CNT to PTFE in a weight ratio of 2.0% to 5.0% by weight of CNT.

5. The vehicle according to claim 1, wherein the LMR cathode active material comprises CNT / PTFE in a weight ratio of 0.5% to 10.0% by weight of LMR.

6. The vehicle according to claim 1, wherein the LMR cathode active material comprises aluminum oxide in a weight ratio of 0.1% to 1.0% by weight.

7. The vehicle according to claim 1, wherein the weight ratio of LMR cathode active material in the cathode active material layer is 80% to 99% by weight.

8. A battery cell, comprising: Anode current collector; The anolyte active material layer is in direct contact with the surface of the anolyte current collector; Cathode current collector; The cathode active material layer is in direct contact with the surface of the cathode current collector, and the cathode active material layer comprises lithium-rich manganese (LMR) cathode active material coated with a fluorine-rich organic / inorganic coating. as well as A separator is positioned between the anode active material layer and the cathode active material layer; The fluorine-rich organic / inorganic coating comprises polytetrafluoroethylene (PTFE) nanofibers filled with carbon nanotubes (CNTs) physically adsorbed onto the LMR cathode active material.

9. The battery cell according to claim 8, wherein the LMR cathode active material comprises nickel with a nickel to manganese molar ratio of 30:70 to 80:

20.

10. The battery cell of claim 8, wherein the LMR cathode active material comprises a lithium to transition metal molar ratio of 1.06 to 1.60.

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