Electrochemical deposition of metal oxide coatings on cathode active materials

Abstract

Aspects of the present disclosure include electrochemically depositing a metal oxide coating on a cathode active material and resulting in a battery cell. An example vehicle includes an electric motor and a battery pack electrically coupled to the electric motor. The battery pack comprises battery units; the battery cell includes 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 between the anode active material layer and the cathode active material layer. The cathode active material layer includes a cathode active material having a metal oxide coating. A metal oxide coating is electrochemically deposited onto the cathode active material.

Description

Technical Field

[0001] This disclosure relates to the fabrication of battery cells, and more particularly to the electrochemical deposition of a metal oxide coating on a cathode active material. Background Technology

[0002] Lithium-ion batteries, also known as lithium-ion batteries, 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 cell is typically made of graphite, a carbon-based material that can reversibly insert and extract 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 can reversibly insert and extract 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, a solid polymer, or a solid electrolyte. During charging and discharging, the electrolyte acts as the medium for lithium-ion transport between the anode and cathode. 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 extracted from the anode and migrate through the electrolyte to embed 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 embedded back 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 a battery cell comprising an anode current collector; an anode active material layer in direct contact with the surface of the anode current collector, the anode active material layer comprising an anode active material, and optionally an anode binder, a conductive material, or both an anode binder and a conductive material; a cathode current collector; a cathode active material layer in direct contact with the surface of the cathode current collector, the cathode active material layer comprising a cathode active material having a metal oxide coating, and optionally a cathode binder, a conductive material, or both a cathode binder and a conductive material; and a separator located between the anode active material layer and the cathode active material layer. The metal oxide coating is electrochemically deposited onto the cathode active material.

[0006] In addition to one or more features described herein, in some embodiments, the metal oxide coating is in the form of MO2, wherein M is titanium, manganese, aluminum, zirconium, zinc, copper, or magnesium.

[0007] In some embodiments, the metal oxide coating is TiO2.

[0008] In some embodiments, the surface of the metal oxide coating includes a thickness variation between 5 nm and 10 nm. In some embodiments, the nominal thickness of the metal oxide coating is between 5 nm and 25 nm.

[0009] In some embodiments, the metal oxide coating comprises an aggregated island morphology.

[0010] In some embodiments, the metal oxide coating comprises a pure crystalline phase.

[0011] 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, the anode active material layer including an anode active material, and optionally an anode binder, a conductive material, or both an anode binder and a conductive material; a cathode current collector; a cathode active material layer in direct contact with the surface of the cathode current collector, the cathode active material including a cathode active material having a metal oxide coating, and optionally a cathode binder, a conductive material, or both a cathode binder and a conductive material; and a separator located between the anode active material layer and the cathode active material layer. The metal oxide coating is electrochemically deposited onto the cathode active material.

[0012] In some embodiments, the metal oxide coating is in the form of MO2, wherein M is titanium, manganese, aluminum, zirconium, zinc, copper, or magnesium.

[0013] In some embodiments, the metal oxide coating is TiO2.

[0014] In some embodiments, the surface of the metal oxide coating includes a thickness variation between 5 nm and 10 nm. In some embodiments, the nominal thickness of the metal oxide coating is between 5 nm and 25 nm.

[0015] In some embodiments, the metal oxide coating comprises an aggregated island morphology.

[0016] In some embodiments, the metal oxide coating comprises a pure crystalline phase.

[0017] In yet another exemplary embodiment, a method may include forming an anolyte current collector, forming an anolyte active material layer in direct contact with the surface of the anolyte current collector, the anolyte active material layer comprising an anolyte active material and optionally an anolyte binder, a conductive material, or both an anolyte binder and a conductive material, forming a cathode current collector, forming a cathode active material layer in direct contact with the surface of the cathode current collector, the cathode active material layer comprising a cathode active material having a metal oxide coating, and optionally a cathode binder, a conductive material, or both a cathode binder and a conductive material, and forming a spacer located between the anolyte active material layer and the cathode active material layer. The metal oxide coating is electrochemically deposited onto the cathode active material.

[0018] In some embodiments, the metal oxide coating is in the form of MO2, wherein M is titanium, manganese, aluminum, zirconium, zinc, copper, or magnesium.

[0019] In some embodiments, the metal oxide coating is TiO2.

[0020] In some embodiments, the surface of the metal oxide coating includes a thickness variation between 5 nm and 10 nm. In some embodiments, the nominal thickness of the metal oxide coating is between 5 nm and 25 nm.

[0021] In some embodiments, the metal oxide coating comprises an aggregated island morphology.

[0022] In some embodiments, the metal oxide coating comprises a pure crystalline phase.

[0023] 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

[0024] Other features, advantages, and details appear as examples only in the following detailed description, with reference to the accompanying drawings.

[0025] Figure 1 It is a vehicle configured according to one or more embodiments;

[0026] Figure 2 These are example battery cells according to one or more embodiments;

[0027] Figure 3 It is an electrochemical deposition system for coating a cathode active material with a metal oxide coating, according to one or more embodiments;

[0028] Figure 4 This is a manufacturing process for coating a cathode active material with a metal oxide coating according to one or more embodiments;

[0029] Figure 5A computer system according to one or more embodiments; and

[0030] Figure 6 It is a flowchart according to one or more embodiments. Detailed Implementation

[0031] 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.

[0032] Driven in part by the surge in electric vehicles, the increasing demand for energy storage systems that offer higher energy density, faster charging, and extended operational life has placed significant challenges on the materials used in battery cell components. Research and development efforts are continuously dedicated to identifying new materials and manufacturing technologies that can meet the growing demands for battery cells and other energy storage systems.

[0033] High-energy-density cathode active materials (CAMs), such as Ni-rich and Mn-rich CAMs, show great promise as next-generation cathode materials for lithium-ion batteries. However, their practical application faces several challenges, including initial irreversible capacity loss and poor cycle stability associated with these materials. Various techniques for surface-coating electrode particles have been demonstrated to enhance the performance of cathode active materials in lithium-ion battery cells, resulting in batteries that offer less capacity loss and longer cycle life. Unfortunately, while vapor deposition techniques such as atomic layer deposition (ALD) and chemical vapor deposition (CVD) can provide precise control over coating thickness, these processes are somewhat complex and not easily scalable.

[0034] This disclosure introduces a wet chemistry-based method that is cost-effective and scalable for coating CAMs with metal oxide coatings. Specifically, an electrochemical method is provided for forming and / or depositing metal oxide (e.g., TiO2) coatings on the surface of cathode particles. Lithium-ion batteries fabricated using the wet chemistry-based method described herein offer numerous advantages over existing batteries. For example, the wet chemistry-based method described herein can be performed as a room-temperature process, where precise control of coating thickness is provided by controlling charge transfer per unit time. In other words, instead of relying on relatively complex techniques such as ALD and CVD, an aqueous and wet chemistry-based electrochemical method for electrodepositing metal oxide coatings (e.g., TiO2) on cam surfaces is described.

[0035] According to an exemplary embodiment, the vehicle is in Figure 1The 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 separately indicated) 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-electric-motor configurations) are within the scope of this disclosure.

[0036] 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 illustrative and discussion purposes 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 in 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.

[0037] Figure 2 An example battery cell 200 according to one or more embodiments is shown. The battery cell 200 can serve as a battery pack (e.g., Figure 1 One of the multiple battery cells in the battery pack 108 is incorporated. For example... Figure 2 As shown, the battery cell 200 includes an anode current collector 202, an anode active material layer 204, a separator 206, a cathode active material layer 208, and a cathode current collector 210, configured and arranged as shown.

[0038] Anode current collector 202 and cathode current collector 210 collect free electrons and move them to and from external circuit 212, respectively. In some embodiments, external circuit 212 includes load device 214 (e.g., Figure 1The electric motor 106 is mentioned. In some embodiments, the external circuit 212 and the load device 214 connect the anode active material layer 204 (via the anode current collector 202, also referred to as the negative electrode) and the cathode active material layer 208 (via the cathode current collector 210, also referred to as the positive electrode). The anode current collector 202 and the cathode current collector 210 may be made of sheets, foils (continuous or perforated or slitted), or meshes of conductive material. For example, the cathode current collector 210 may be made of aluminum foil, stainless steel, and / or titanium foil. Other materials are also 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 210 is made of aluminum foil. The anode current collector 202 may include, for example, copper foil and / or one or more graphene layers. In some embodiments, the anode current collector 202 is made of copper foil. The thickness of the current collector may be approximately 10 μm to 20 μm, but other thicknesses are also within the scope of this disclosure.

[0039] The anolyte active material layer 204 is not particularly limited and may include, for example, lithium metal, activated carbon powder, carbon-based materials (such as graphite, silicon), silicon-based materials (such as LixSi, SiOx, LiSiOx, and nano-Si), silicon-graphite composites, tin, tin oxide (SnO2), tin-cobalt alloys, and lithium titanate (Li4Ti5O2). 12 The anode active material layer 204 may include conductive materials such as carbon black, graphene, and / or carbon nanotubes. The anode active material layer 204 may further include binder materials such as poly(tetrafluoroethylene) (PTFE), sodium carboxymethyl cellulose (CMC), styrene-butadiene rubber (SBR), poly(vinylidene fluoride) (PVDF), nitrile rubber (NBR), styrene-ethylene-butene-styrene copolymer (SEBS), styrene-butadiene-styrene copolymer (SBS), lithium polyacrylate (LiPAA), sodium polyacrylate (NaPAA), sodium alginate, lithium alginate, ethylene propylene diene monomer (EPDM), and combinations thereof. The anode active material layer 204 may include, for example, more than or equal to about 0% by weight to less than or equal to about 20% by weight, and in some aspects, optionally more than or equal to about 5% by weight to less than or equal to about 15% by weight of one or more binders.

[0040] For example, regarding Figure 3 and Figure 4 In a more detailed description, the cathode active material layer 208 may include a cathode active material coated with a metal oxide (i.e., a CAM having a metal oxide coating) (e.g., cathode active material 302, see [link]). Figure 3The cathode active material is not intended to be particularly limited and may include, for example, nickel manganese cobalt oxide (NMC), lithium iron phosphate (LFP), nickel cobalt aluminum oxide (NCA), nickel cobalt manganese aluminum oxide (NCMA), lithium manganese iron phosphate (LMFP), lithium-rich manganese (LMR), lithium manganese oxide (LMO), lithium nickel manganese oxide (LNMO), and blends and combinations thereof. In some embodiments, the cathode active material comprises a material having a negative electrode capacity to positive electrode capacity ratio (also referred to as an N to P ratio) between 1 and 3. In some embodiments, the cathode active material layer 208 may comprise nickel manganese cobalt (NMC) variants such as NMC 622, NMC 811, and NMC 532. In some embodiments, the cathode active material layer 208 may comprise nickel and manganese in a molar ratio of 30:70 to 80:20. In some embodiments, the cathode active material layer 208 may also comprise Co in the range of 0% to 20%. The cathode active material layer 208 may further comprise a binder material in a manner similar to that described with respect to the anode active material layer 204.

[0041] Depending on the battery construction (e.g., conventional current collectors versus bipolar current collectors, etc.), separator 206 is optional, but if included, separator 206 can be positioned to isolate the anode active material layer 204 and the cathode active material layer 208. Separator 206 also provides a path of least resistance for the interior of lithium ions (and in some cases, associated anions) during lithium-ion cycling. Separator 206 may include dielectric materials such as polyethylene (PE), polypropylene (PP), polyethylene terephthalate (PET), synthetic fluoropolymers such as polytetrafluoroethylene (PTFE), and their composites, but other dielectrics are also within the scope of this disclosure. In some embodiments, separator 206 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 206 may be about 12 to 16 μm, but other thicknesses are also within the scope of this disclosure.

[0042] like Figure 2As further shown, the battery cell 200 includes an electrolyte 216. The electrolyte 216 may include a liquid electrolyte, a solid electrolyte, and / or a polymer electrolyte. In some embodiments, the electrolyte 216 is a liquid electrolyte that permeates, covers, penetrates, or partially penetrates the cathode active material layer 208, the separator 206, and / or the anode active material layer 204. In some embodiments, the 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 in the 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.

[0043] The concentration of the lithium salt in electrolyte 216 will vary depending on the selected lithium salt 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 may decrease 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 impede ion mobility sufficiently 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.

[0044] Figure 3 An electrochemical deposition system 300 for coating a cathode active material 302 with a metal oxide coating 304, according to one or more embodiments, is shown. Figure 3As shown, the electrochemical deposition system 300 may include a container 306. In some embodiments, the conductive inner surface 308 of the container 306 serves as an anode 310. In some embodiments, the anode 310 is electrically connected to a cathode 312 positioned within the container 306. In some embodiments, the container 306 is filled with solutions 314 and 316 separated by an ion exchange membrane 318. In some embodiments, the container 306 may include a mixer 320 (or a stirrer, etc.) within solution 316. In some embodiments, the speed of the mixer 320 may be controlled (see reference). Figure 5 This increases the contact between the cathode active material 302 and the anode 310.

[0045] In some embodiments, solution 314 comprises an aqueous solution of HCl (aq). In some embodiments, solution 314 is a reducing solution in which hydrogen atoms (H+, protons) are reduced at cathode 312 to form molecular hydrogen (H2).

[0046] In some embodiments, solution 316 contains a metal chloride (MCl). x Solution 316 is an aqueous solution of TiCl3 and HCl(aq), wherein M is titanium, manganese, aluminum, zirconium, zinc, copper, magnesium, etc., and x is 1, 2, 3, or 4. For example, solution 316 may include an aqueous solution of TiCl3 / HCl(aq). Other chemicals include, for example, MnCl3, AlCl3, ZrCl3, CuCl3, and MgCl3. Solution 316 further includes cathode active material 302 dispersed throughout. In some embodiments, solution 316 is an oxidizing solution, wherein due to metal ions (e.g., Ti when M is Ti), 3+ When M is Mg, Mg 3+ Oxidation of (etc.) at the anode 310 (at the conductive inner surface 308) can cause the cathode active material 302 to become coated with a metal oxide coating 304. In some embodiments, oxygen in the cathode active material 302 reacts with metal ions during this process, thereby depositing a metal oxide (MO2) on the cathode active material 302, where M is titanium, manganese, aluminum, zirconium, zinc, copper, magnesium, etc., as previously discussed. In other words, from metal chloride (MCl) x Metal M can be transmitted via metal ions (e.g., Ti). 3+ The transfer of metal oxides is electrochemically deposited onto the cathode active material 302.

[0047] Coating the cathode active material 302 with a metal oxide coating 304 in this manner offers numerous advantages over existing processes. Specifically, due to random collisions between the cathode active material 302 and the anode 310, the cathode active material 302 can be gradually coated with the metal oxide coating 304 over time without requiring relatively complex vapor deposition techniques such as ALD and CVD. Furthermore, the cathode active material 302 coated with the metal oxide coating 304 using the previously described electrochemical deposition system 300 results in physical differences compared to cathode active materials coated with metal oxides using vapor deposition techniques. For illustration, consider an example scenario where CAM is coated with TiO2, as previously described. The particle size of the cathode active material 302 can range from 1 micrometer to 10 micrometers, and the metal oxide coating 304 can be formed with a nominal (average) thickness between 1 nm and 25 nm or between 5 nm and 25 nm (allowing for thickness variations of up to 5 nm, as described in more detail below). However, compared to metal oxide coatings formed using vapor deposition techniques, the metal oxide coating 304 will have varying thicknesses, different morphologies, and pure crystalline structures. Specifically, the metal oxide coating 304 will have a thickness variation between 5 nm and 10 nm, while vapor deposition technology results in a thickness variation between 1 nm and 3 nm. In other words, the electrochemical deposition system 300 results in a relatively higher thickness variation for the metal oxide coating 304 than that provided by using vapor deposition technology (e.g., the thickness variation increases by nearly two times to over 300%). Furthermore, because the metal oxide is deposited at the collision surface between the cathode active material 302 and the anode 310 (therefore, this is a non-uniform deposition process), the metal oxide coating 304 will have a coalescing island morphology (also known as agglomeration). In contrast, vapor deposition technologies such as ALD and CVD result in uniform layer-by-layer deposition. Finally, the metal oxide coating 304 will have 100% crystalline phase, which is the opposite of the 50% to 70% crystalline phase (the remainder being amorphous phase) when using vapor deposition technologies such as ALD and CVD. Therefore, the varying thickness, different morphologies, and pure crystalline structure of the metal oxide coating 304 described herein can be used with the electrochemical deposition system 300 (and manufacturing process 400, see below) Figure 4 A physical characteristic of ).

[0048] Figure 4 A manufacturing process 400 for coating a cathode active material 302 with a metal oxide coating 304, according to one or more embodiments, is shown. Figure 4 As shown, manufacturing process 400 includes steps 402, 404, 406, 408, 410 and 412 as configured and arranged as shown.

[0049] In some embodiments, step 402 includes suspending the cathode active material 302 (also referred to as electrode material particles) in an aqueous electrolyte solution (e.g., Figure 3 In some embodiments, the cathode active material 302 is suspended in solution 316 at a temperature between about 20 degrees Celsius and 80 degrees Celsius, but other temperatures are also within the range of this disclosure, limited only by the aqueous electrolyte of solution 316 selected for a given application (e.g., about 0 degrees Celsius to about 100 degrees Celsius for most electrolyte solutions).

[0050] In some embodiments, the cathode active material 302 is dispersed in solution 316 at a predetermined pH, which is selected to target a predetermined metal oxide structure and / or phase in the resulting metal oxide coating 304. In some embodiments, the cathode active material 302 is dispersed in solution 316 at a predetermined pH between 1 and 7, or more specifically between 1 and 3, but it should be understood that the pH will vary depending on the selection of the metal oxide coating 304.

[0051] In some embodiments, step 404 includes applying current and / or voltage to solution 316. In some embodiments, step 404 includes applying current and / or voltage across the anode 310 and cathode 312 of the electrochemical deposition system 300 (see reference). Figure 3 The voltage, current, and / or current density will vary depending on the deposition material, the target deposition thickness, and the reactor (vessel) design. The voltage, current, and / or current density may be kept stable or varied as needed to control the nominal thickness of the metal oxide coating 304 deposited on the cathode active material 302, wherein a relatively increased voltage, current, and / or current density results in a relatively thicker coating, and vice versa.

[0052] In some embodiments, step 406 includes maintaining the current and / or voltage for a predetermined time and / or the time required to achieve the target thickness of the metal oxide coating 304. In some embodiments, a sample is removed from solution 316, and the thickness of the metal oxide coating 304 is determined empirically. In some embodiments, the thickness of the metal oxide coating 304 is estimated using data derived from previous experience (e.g., thickness versus time versus current distribution from previous processes).

[0053] In some embodiments, step 408 includes filtering out and rinsing the cathode active material 302 coated with the metal oxide coating 304. The cathode active material 302 coated with the metal oxide coating 304 can be physically and / or chemically filtered from the solution 316 as needed. In this way, the cathode active material 302 coated with the metal oxide coating 304 can be separated from the solution 316, and electrode fabrication and battery assembly can be performed at step 412.

[0054] In some embodiments, step 410 includes recirculating solution 316 (once the cathode active material 302 coated with metal oxide coating 304 has been separated via step 408). In some embodiments, the filtered solution 316 may be returned to the electrochemical deposition system 300 (see reference). Figure 3 ).

[0055] In some embodiments, step 412 involves fabricating a battery cell using a cathode active material 302 coated with a metal oxide coating 304. Step 412 may include, for example, fabricating and / or acquiring a current collector, separator, electrolyte, etc. (see [link to documentation]). Figure 2 ).

[0056] Figure 5 Various aspects of an embodiment of a computer system 500 that can perform various aspects of the embodiments described herein are illustrated. In some embodiments, the computer system 500 may implement an electrochemical deposition system 300 (see reference 300). Figure 3 ) and / or manufacturing process 400 (reference) Figure 4 ) and / or otherwise incorporated into the electrochemical deposition system 300 (reference) Figure 3 ) and / or manufacturing process 400 (reference) Figure 4 ) within or with an electrochemical deposition system 300 (reference) Figure 3 ) and / or manufacturing process 400 (reference) Figure 4 ( ) combinations. For example, in some embodiments, the computer system 500 may control the temperature, pressure, voltage, current, stirring rate, etc. of the electrochemical deposition system 300 during the manufacturing process 400.

[0057] Computer system 500 includes at least one processing device 502, which typically includes one or more processors or processing units for performing various functions, such as, for example, regarding Figure 5 The computer system 500 also includes system memory 504 and bus 506, which connects various system components, including system memory 504, to processing device 502. System memory 504 may include various computer system readable media. Such media may be any available media accessible by processing device 502, and include volatile and non-volatile media as well as removable and non-removable media. For example, system memory 504 includes non-volatile memory 508 such as a hard disk drive, and may also include volatile memory 510, such as random access memory (RAM) and / or cache memory. Computer system 500 may also include other removable / non-removable, volatile / non-volatile computer system storage media.

[0058] System memory 504 may include at least one program product having a set (e.g., at least one) of program modules configured to perform the functions of the embodiments described herein. For example, system memory 504 stores various program modules that typically perform the functions and / or methods of the embodiments described herein. One or more modules 512, 514 may be included to perform functions associated with any block diagram described herein. Computer system 500 is not limited thereto, as other modules may be included depending on the desired functionality of computer system 500. As used herein, the term "module" refers to circuitry that can process circuitry, including application-specific integrated circuits (ASICs), electronic circuitry, processors (shared, dedicated, or grouped) and memories executing one or more software or firmware programs, combinational logic circuitry, and / or other suitable components that provide the described functions.

[0059] The processing device 502 can also be configured to communicate with one or more external devices 516, such as, for example, a keyboard, pointing devices, and / or any device that enables the processing device 502 to communicate with one or more other computing devices (e.g., a network interface card, a modem, etc.). Communication with various devices can occur via input / output (I / O) interfaces 518 and 520.

[0060] Processing device 502 can also communicate with one or more networks 522, such as a local area network (LAN), a general wide area network (WAN), a bus network, and / or a public network (e.g., the Internet), via network adapter 524. In some embodiments, network adapter 524 is or includes an optical network adapter for communication over an optical network. It should be understood that, although not shown, other hardware and / or software components may be used in conjunction with computer system 500. Examples include, but are not limited to, microcode, device drivers, redundant processing units, external disk drive arrays, RAID systems, and data archiving storage systems.

[0061] Now for reference Figure 6 A flowchart 600 for electrochemically depositing a metal oxide coating on a cathode active material is generally shown according to one embodiment. (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 blocks depicted can be rearranged, subdivided, and / or combined.

[0062] At box 602, the method includes forming an anode current collector.

[0063] At block 604, the method includes forming an anolyte active material layer in direct contact with the surface of the anolyte current collector. In some embodiments, the anolyte active material layer comprises an anolyte active material and optionally includes an anolyte adhesive, a conductive material, or both an anolyte adhesive and a conductive material.

[0064] At block 606, the method includes forming a cathode current collector.

[0065] 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 a cathode active material having a metal oxide coating, and optionally, a cathode adhesive, a conductive material, or both a cathode adhesive and a conductive material.

[0066] At frame 610, the method includes forming a spacer located between the anode active material layer and the cathode active material layer.

[0067] In some embodiments, the metal oxide coating is in the form of MO2, wherein M is titanium, manganese, aluminum, zirconium, zinc, copper, or magnesium.

[0068] In some embodiments, the metal oxide coating is TiO2.

[0069] In some embodiments, the surface of the metal oxide coating includes a thickness variation between 5 nm and 10 nm. In some embodiments, the nominal thickness of the metal oxide coating is between 5 nm and 25 nm.

[0070] In some embodiments, the metal oxide coating comprises an aggregated island morphology.

[0071] In some embodiments, the metal oxide coating comprises a pure crystalline phase.

[0072] The terms “a” and “an” do 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.

[0073] 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 conjunction with specific examples in 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}.

[0074] When a component, such as a layer, film, region, or substrate, is referred to as being “on” another component, it can be directly on the other component, or there may be intermediate components. Conversely, when a component is referred to as being “directly” on another component, there are no intermediate components.

[0075] Unless otherwise stated herein, all test standards are the most recent standards effective up to the filing date of this application, or, if priority is claimed, the most recent standards effective up to the filing date of the earliest priority application in which the test standards appear.

[0076] 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.

[0077] 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: an electric motor; and a battery pack electrically coupled to the electric motor, the battery pack comprising a plurality of battery cells, each battery cell of the plurality of battery cells comprising: an anode current collector; a layer of anode active material in direct contact with a surface of the anode current collector, the layer of anode active material comprising anode active material and optionally anode binder, conductive material, or both anode binder and conductive material; a cathode current collector; a layer of cathode active material in direct contact with a surface of the cathode current collector, the layer of cathode active material comprising cathode active material with a metal oxide coating, and optionally cathode binder, conductive material, or both cathode binder and conductive material; and a separator positioned between the layer of anode active material and the layer of cathode active material; wherein the metal oxide coating is electrochemically deposited onto the cathode active material.

2. The vehicle of claim 1, wherein the metal oxide coating is in the form of MO2, where M is titanium, manganese, aluminum, zirconium, zinc, copper, or magnesium.

3. The vehicle of claim 2, wherein the metal oxide coating is TiO2.

4. The vehicle of claim 1, wherein a surface of the metal oxide coating comprises a thickness variation of 5 nm to 10 nm.

5. The vehicle of claim 4, wherein a nominal thickness of the metal oxide coating is 5 nm to 25 nm.

6. The vehicle of claim 1, wherein the metal oxide coating comprises a merged island morphology.

7. The vehicle of claim 1, wherein the metal oxide coating comprises a pure crystalline phase.

8. A battery cell comprising: an anode current collector; a layer of anode active material in direct contact with a surface of the anode current collector, the layer of anode active material comprising anode active material and optionally anode binder, conductive material, or both anode binder and conductive material; a cathode current collector; a layer of cathode active material in direct contact with a surface of the cathode current collector, the layer of cathode active material comprising cathode active material with a metal oxide coating, and optionally cathode binder, conductive material, or both cathode binder and conductive material; and a separator positioned between the layer of anode active material and the layer of cathode active material; wherein the metal oxide coating is electrochemically deposited onto the cathode active material.

9. The battery cell of claim 8, wherein the metal oxide coating is in the form of MO2, where M is titanium, manganese, aluminum, zirconium, zinc, copper, or magnesium.

10. The battery cell of claim 9, wherein the metal oxide coating is TiO2. ​

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