Cathode with prelithiation coating and method of making and use thereof

Abstract

Methods and systems for cathode materials for lithium ion batteries are provided. In an embodiment, the cathode material can include a lithium mixed metal oxide core and a surface coating that coats the core. Optionally, a passivation layer can continuously coat the surface coating. In some embodiments, the surface coating or surface layer can include a lithiation supplementing material, a lithium-based active cathode catalyst, or a combination thereof. In other embodiments, methods of manufacturing cathode materials for lithium ion batteries are provided.

Description

[0001] Cross-reference to related applications

[0002] This application claims priority to U.S. Provisional Application No. 62 / 784,283, filed December 21, 2018, entitled "Cathode with Pre-lithiation Coating, Method of Preparation Thereof and Use Thereof," the entire contents of which are incorporated herein by reference for all purposes. Technical Field

[0003] This disclosure generally relates to cathode materials, methods for their preparation, and their use in lithium-ion batteries.

[0004] Background Art and Invention Content

[0005] Lithium (Li)-ion batteries are being and have been widely used in many different applications, including but not limited to consumer electronics, uninterruptible power supplies, transportation, and stationary applications. To meet the growing demand for energy storage, especially for electric vehicles, attention has turned to high-energy-density lithium-ion hybrid metal oxide layered structures, which offer higher energy density, wider voltage windows, and longer cycle life compared to other similar materials. Examples include high-nickel-content cathode active materials such as lithium nickel manganese cobalt oxide (LiNi). x Mn y Co 1-x-y O2 or NMC) and lithium nickel cobalt aluminum oxide (LiNi x Co y Al 1-x-y O2 or NCA has been used in the production of high-energy lithium-ion batteries. Compared with other materials, these layered lithium mixed metal oxide compounds have a voltage greater than 3.0V (vs. Li / Li). + It can provide a higher capacity of up to about 200 mAh / g at a potential.

[0006] Lithium-ion batteries operate by transferring lithium ions from the positive electrode or cathode (containing the positive electrode active material) to the lithium-based negative electrode or anode during charging, and then transferring them back from the anode to the cathode during discharging. The result of this charge / discharge process is the formation of a solid electrolyte interphase (SEI) layer on the anode during the first charge cycle. Because this formation process leads to significant Li-ion consumption, especially in silicon-based anodes (unlike pure graphite anodes), the SEI can impair electrochemical performance. Thus, in anodes comprising silicon or silicon-graphite composites, SEI formation can reduce the first-cycle coulombic efficiency (FCE).

[0007] To combat low FCE due to anode SEI formation, a pre-lithiation approach can be employed to provide the anode with extra lithium ions prior to or during the first charge / discharge. This pre-lithiation approach can be implemented in a variety of ways, such as chemical treatment of the anode or incorporation of a sacrificial Li source on the cathode. For the latter case, a sacrificial Li source can be added to the cathode such that a greater amount of lithium ions can flow to the anode during the initial charge of the lithium-ion battery. A cathode catalyst (CC), such as a lithium-based active cathode catalyst (ACC), can be further incorporated to lower the potential and increase the rate of decomposition of the sacrificial Li source. It should be understood that in many cases, a given catalyst can be selected to lower the activation energy of a reaction, where the catalyst does not undergo any permanent chemical change. However, while a given ACC can act as a catalyst to lower the overpotential of the decomposition of the sacrificial Li source, the voltage profile of the ACC can change with the action of the catalyst. This change in voltage profile can account for structural changes in the ACC or its surface that accompany the catalysis. Regardless, the ACC can still provide reversible capacity and act as an active material in a given battery system after the catalytic action.

[0008] In certain cases, a lithium-based ACC can act as a catalyst prior to releasing lithium during the charging of a lithium-ion battery. In certain cases, a lithium-based ACC can be partially or fully charged prior to acting as a catalyst. In such cases, the lithium-based ACC can have partially or fully lost Li in its structure, and the corresponding Li-deficient structure can be considered the actual CC that catalyzes the decomposition reaction of the sacrificial Li source.

[0009] Attempts have been made to utilize lithium supplementing materials that would make additional lithium ions available to the anode, which would decompose to provide additional lithium ions and not reform upon discharge. For example, U.S. Patent Application Publication No. 2017 / 0309914 provides a cathode coated with a lithium active material that is slurry coated with lithium peroxide (Li2O2) as a lithium supplementing material and cobalt tetroxide (Co3O4) as a CC. However, there is no provision for protecting the lithium supplementing material from reaction with electrolyte components. In another example, Bie et al. in “Li2O2 as a Cathode Additive for the Initial Anode Irreversibility Compensation in Lithium-Ion Batteries” (Chem. Commun., 2017, vol. 53, pp. 8324-8327, 2017) provide a battery cell comprising an NMC-based cathode fabricated by a slurry-based process that includes Li2O2 as a lithium supplementing material and other NMC ball milled to smaller particles as an ACC. However, using NMC as an ACC shows poor reversibility. Thus, the smaller NMC particles can affect performance after a few cycles as inert residues. Additional inert residues lithium hydroxide and lithium carbonate can be created due to the interaction of Li2O2 with air and / or moisture in the battery cell, which can further degrade electrochemical performance.

[0010] In an alternative approach, anti-fluorite structure materials such as Li5FeO4 can be used as lithium supplementing materials (see, for example, Su et al. in “A New Strategy to Mitigate the Initial Capacity Loss of Lithium Ion Batteries” (J. Power Sources, 2016, vol. 324, pp. 150-157) and Zhan et al. in “Enabling the High Capacity of Lithium-Rich Anti-Fluorite Lithium Iron Oxide by Simultaneous Anionic and Cationic Redox” (Nat. Energy, 2017, vol. 2, pp. 963-971)). Such materials can be advantageous because their decomposition can not require CC. However, as discussed above with respect to Li2O2, sensitivity to impurities, manufacturing conditions, and / or electrolyte components such as moisture can affect performance.

[0011] The inventors have discovered the above problems and identified solutions to address them, at least in part. As described in detail herein, a cathode structure is presented to overcome the difficulties set forth above. In one embodiment, a cathode material for a lithium-ion battery can include lithium-mixed metal oxide (e.g., NMC) core particles coated with a lithiation supplement material (e.g., lithium peroxide), and optionally an active cathode catalyst. In another or alternative embodiment, the lithiation supplement material can be a lithium aluminum oxide, a fluorite-structured material that has the above-mentioned advantages as well as other benefits of providing a decomposition byproduct that can have a secondary purpose (e.g., safety, cycle stability) similar to an aluminum oxide coating. The coated core particles are optionally further coated with a passivation layer that allows release of at least some of the decomposition byproduct, e.g., oxygen, while protecting the coated core particles from impurities and / or electrolyte components, e.g., water or other solvents. In this way, performance degradation caused by inert residues in a battery cell containing the cathode material can be mitigated.

[0012] As another embodiment, a method for manufacturing a cathode material can include milling a lithiation supplement material powder and a cathode catalyst powder to a predetermined average particle size. In this way, optimal performance can be achieved by selecting each particle size of the powders as well as the weight ratio of the lithiation supplement material powder to the cathode catalyst powder. The method can further include mixing a lithiated core powder with the lithiation supplement material powder and the cathode catalyst powder, whereby a coated core material can be obtained. An optional passivation layer can then be applied to protect the coated core material from harmful impurities and / or electrolyte components.

[0013] In yet another embodiment, a method for manufacturing a cathode material can include converting a surface layer of a lithiated core material into a lithiation supplement material and / or a cathode catalyst, whereby a coated core material can be obtained. In some embodiments, the surface layer can include a chemical precursor. In additional or alternative embodiments, the surface layer can include the lithiated core material itself, which can include impurities. The impurities can be formed during synthesis of the lithiated core material. The impurities can include, but are not limited to, Li20, LiOH, and Li2C03. In these or alternative embodiments, the surface layer can include impurities that remain from the synthesis of the lithiated core material. In this way, the lithiation supplement material and / or the cathode catalyst can be formed chemically on the surface of the lithiated core material. An optional passivation layer can then be applied to protect the coated core material from harmful impurities and / or electrolyte components.

[0014] It is to be understood that the foregoing summary of the application is intended merely to introduce some of the concepts underlying the specific embodiments described herein. It does not limit, in any way, the scope of the claimed subject matter to the specific embodiments described herein. Furthermore, the claimed subject matter is not limited to implementations that solve any or all of the disadvantages of the prior art described herein or in any part of this disclosure. BRIEF DESCRIPTION OF DRAWINGS

[0015] Figure 1 A schematic of a coated positive active material with a lithiu m supplementing material, cathode catalyst (CC) particles, and a passivation layer is shown.

[0016] Figure 2 A schematic of a coated positive active material with at least a lithium supplementing material and CC particles in the surface coating is shown.

[0017] Figure 3 A schematic of a first embodiment of decomposition of one or more lithium supplementing materials present in a coated positive active material is shown.

[0018] Figure 4 A schematic of a second embodiment of decomposition of one or more lithium supplementing materials present in a coated positive active material is shown.

[0019] Figure 5 A schematic of a third embodiment of decomposition of one or more lithium supplementing materials present in a coated positive active material is shown.

[0020] Figure 6 A method of mixing a positive active material powder with a lithium supplementing material powder and a lithium-based active CC (ACC) powder is shown.

[0021] Figure 7 A method of mixing a positive active material with a lithium supplementing material is shown.

[0022] Figure 8 A method of converting a surface layer of a positive active material into a lithium supplementing material and / or a CC is shown.

[0023] Figure 9 A potential of a lithium ion battery operating at two charge rates is shown, the lithium ion battery comprising at least a cathode comprising a lithium supplementing material.

[0024] Figure 10 A potential of a lithium ion battery comprising at least a cathode is shown, wherein each cathode comprises a different ratio of ACC to lithium supplementing material.

[0025] Figure 11 A particle size distribution of a lithium peroxide slurry before and after milling is shown.

[0026] Figure 12 X-ray diffraction (XRD) patterns of the pristine cathode and the cathode after cycling are shown.

[0027] Figure 13A Scanning electron microscope (SEM) images of coated cathode active material particles are shown.

[0028] Figure 13B Energy dispersive X-ray spectroscopy (EDS) mapping of coated cathode active material particles is shown.

[0029] Figure 13C XRD patterns of coated cathode active material are shown.

[0030] Figure 14 First charge cycle (FCC) voltage profiles of half cells including cathodes without a lithium supplement material and cathodes with a lithium supplement material, respectively, are shown.

[0031] Figure 15 FCC voltage profiles of full cells including cathodes without a lithium supplement material and cathodes with a lithium supplement material, respectively, are shown.

[0032] Figure 16 Discharge capacities during initial cycles of full cells including cathodes without a lithium supplement material and cathodes with a lithium supplement material, respectively, are shown.

[0033] Figure 17A A schematic of a method of impregnating carbon source particles with lithium supplement material particles is shown.

[0034] Figure 17B A schematic of a method of coating cathode active material particles with impregnated carbon source particles, followed by decomposition of lithium supplement material particles therein, is shown.

[0035] Figure 18 A method of forming carbon sources impregnated with lithium supplement material, and then coating cathode active material with the impregnated carbon sources is shown. DETAILED DESCRIPTION

[0036] The following description relates to systems and methods for cathode materials containing a lithiated compound core and a surface coating. The core can be a lithium complex compound, such as a lithium metal oxide (LMO), a lithium phosphated compound, or a combination thereof. In this context, "lithium metal oxide" or "LMO" can refer to any oxide compound that includes lithium and at least one metal element. Likewise, "lithium phosphated compound" as used herein can refer to any phosphate compound that includes lithium. Further, "lithium mixed metal oxide" can refer to any oxide compound that includes lithium and at least two metal elements.

[0037] The surface coating can coat the core and can include lithium supplementing material particles including lithium peroxide, lithium aluminum oxide (LAO), lithium iron oxide (LFO), lithium oxide, lithium nitride, lithium sulfide, lithium azide, a conversion-type pre-lithiation reagent, or a combination thereof. In this context, lithium peroxide can refer to a compound having a Li2O2 composition, lithium aluminum oxide or LAO can refer to a compound having a Li5AlO4 composition, lithium iron oxide or LFO can refer to a compound having a Li5FeO4 composition, lithium oxide / lithia can refer to a compound having a Li2O composition, lithium nitride can refer to a compound having a Li3N composition, lithium sulfide can refer to a compound having a Li2S composition, lithium azide can refer to a compound having a LiN3 composition. The conversion-type pre-lithiation reagent can be a mixture of one or more metals with one or more of Li2O, LiF, and / or Li2S, such that a conversion reaction can release lithium ions and a corresponding metal compound, such as a metal oxide, a metal fluoride, or a metal sulfide. The surface coating can further include cathode catalyst (CC) particles including one or more of a metal oxide, LMO, a lithium phosphated compound, a metal phosphated compound, or a combination thereof.

[0038] The passivation layer can be considered to coat the surface coating (or surface layer) continuously, uniformly, or discretely, such that the surface coating can be disposed between the core and the passivation layer. In this context, when describing a shell and / or layer and / or coating of a particle, “continuous” or “continuously” or “conformal” or “conformally” can refer to a complete or substantially complete coverage of a coated surface area of the particle with a continuous or conformal film. Further, when describing a shell and / or layer and / or coating of a particle, “uniform” or “uniformly” can refer to a similar or substantially similar amount of coverage of any portion of a coated surface area of the particle relative to any other portion of the coated surface area of the particle. Further, when describing a shell and / or layer and / or coating of a particle, “discrete” or “discretely” can refer to a complete or substantially complete coverage of a coated surface area of the particle with a discrete layer of particles. Further, as used herein, “about” can refer to a numerical value having a tolerance or deviation of up to 10%.

[0039] Figure 1 and Figure 2 Embodiments of coated positive electrode active material particles that can be used as cathode materials are shown. Figure 1A schematic of a core particle is shown, where the core particle can have a surface coating comprising lithium supplementing material particles and CC particles. The surface coating can be further coated with a passivation layer, such that the surface coating can be disposed between the core particle and the passivation layer. Figure 2 A schematic of a core particle is shown, where the core particle can have a surface coating comprising lithium supplementing material particles and CC particles, and a binder.

[0040] Figures 3-5 An example of a decomposition process of lithium supplementing material particles is shown. Figure 3 A catalytic decomposition process of at least two lithium supplementing materials present in a surface coating of a core particle is shown, where at least two decomposition products and a residue can be produced. Figure 4 A catalytic decomposition process of a lithium supplementing material present in a surface coating of a core particle is shown, where at least two decomposition products can be produced. Figure 5 A catalytic decomposition process of a lithium supplementing material present in a surface coating of a core particle is shown, where at least two decomposition products and a residue can be produced.

[0041] Figures 6-8 An embodiment of a method of manufacturing coated positive active material particles is shown. Figure 6 A method of applying a lithium supplementing material powder and an active CC (ACC) powder onto a core powder, and then applying a passivation layer thereon is shown. Figure 7 A method of applying a surface coating comprising a lithium supplementing material onto a core material, and then applying a passivation layer thereon is shown. Figure 8 A method for transforming a surface layer of a core material to obtain a lithium supplementing material and / or a CC, and then applying a passivation layer thereon is shown.

[0042] To illustrate the dependence of electrochemical performance on charge rate, in Figure 9 The potential of a lithium ion battery comprising a cathode containing at least a lithium supplementing material is shown in Figure 10 , where the lithium ion battery is operated at two different charge rates. The effect of the ratio of ACC to lithium supplementing material on the potential of the lithium ion battery is shown in

[0043] The particle size distribution (PSD) of lithium supplementing material particles before and after milling is shown in Figure 11 , as an example of the relative particle size range employed herein.

[0044] Figure 12 X-ray diffraction (XRD) patterns showing the effect of cycling on the components of a cathode containing a lithium supplementing material and a CC are shown.

[0045] Figures 13A-13C Scanning electron microscope (SEM) and XRD characterization of coated positive active materials are shown. Figure 13ASEM images showing the unique morphological coating characteristics of the coated cathode active material particles are shown. As shown in Figure 13B Energy dispersive X-ray spectroscopy (EDS) mapping images overlaid on SEM images of a large number of coated cathode active material particles are shown. Figure 13C XRD spectra shown confirm the presence of lithium peroxide and lithium manganese iron phosphate (LMFP) in the coated cathode active material particles. Figure 13A and 13B The coated cathode active material particles shown contain lithium peroxide and lithium manganese iron phosphate (LMFP).

[0046] In Figure 14 , the voltage profiles of the first charge cycle (FCC) of half-cells including cathodes without and with lithium supplementing material, respectively, are compared. Similarly, in Figure 15 , the voltage profiles of the first charge cycle (FCC) of full-cells including cathodes without and with lithium supplementing material, respectively, are compared. In Figure 16 , the discharge capacities of full-cells including cathodes without and with lithium supplementing material, respectively, during the initial four charge cycles are compared.

[0047] A carbon source, which can include porous conductive carbon, can be impregnated with a lithium supplementing material, such as shown in the flowchart in Figure 17A and the method shown in Figure 18 . Subsequently, the coated cathode active material can be coated with the impregnated carbon source to form a coated cathode active material, such as shown in the method in Figure 17B and Figure 18 . The coated cathode active material can then be placed within a lithium ion battery, wherein the lithium supplementing material contained in the impregnated carbon source can decompose into one or more decomposed particles, as further shown in Figure 17B .

[0048] Referring to Figure 1 , a coated cathode active material particle 100 is shown. The coated cathode active material particle 100 is schematically shown as having a core 102 coated by a surface coating 104 and a passivation layer 112.

[0049] The core or core particle 102 can be composed of a lithium composite compound. The lithium composite compound can be an LMO, a lithium phosphate compound, or a combination thereof, but is not limited to these types of electrochemically active materials. For example, the core 102 can be a lithium mixed metal oxide layered structure material. In some embodiments, the lithium composite compound can include one or more metals selected from a group including, but not limited to, Ni, Mn, Co, Al, Mg, Y, Nd, B, Ca, V, Zn, and combinations thereof. In other embodiments, the one or more metals can be selected from a group including, but not limited to, Ni, Mn, Co, Al, Mg, Y, Nd, B, Ca, V, Zn, Fe, Mg, Ga, Nb, Cr, Mo, W, Tc, Ru, Rh, Ir, Pd, Cu, Ge, Si, In, Ag, Cd, and combinations thereof. In some embodiments, the lithium composite compound can include a lithium mixed metal oxide. In additional or alternative embodiments, the lithium mixed metal oxide can include a high nickel content. In an embodiment, the lithium mixed metal oxide can include a lithium nickel manganese cobalt oxide (NMC). The NMC can have a structural formula of LiNi x Mn y Co 1-x-y O2. Exemplary components of the NMC can include LiNi 0.333 Mn 0.333 Co 0.333 O2(NMC111), LiNi 0.5 Mn 0.2 Co 0.3 O2(NMC523), LiNi 0.6 Mn 0.2 Co 0.2 O2(NMC622), and LiNi 0.8 Mn 0.1 Co 0.1 O2(NMC811). The NMC can be a single phase crystal, or the NMC can be a polycrystalline or amorphous form. In other embodiments, the lithium mixed metal oxide can include a lithium nickel cobalt aluminum oxide (NCA). The NCA can have a structural formula of LiNi x Co y Al 1-x-y O2. In additional or alternative embodiments, the lithium composite compound can include a lithium phosphate compound including one or more metals selected from Fe, V, Mn, and combinations thereof.

[0050] In some embodiments, the average particle size of the core particles 102 can be at least 1 pm and at most 20 pm. In other embodiments, the average particle size of the core particles 102 can be at least 3 pm and at most 20 pm. In further embodiments, the average particle size of the core particles 102 can be at least 6 pm and at most 12 pm. In additional or alternative embodiments, each core particle 102 can have a substantially similar particle size to each other core particle 102. In some embodiments, a relationship can be formed between the core particles 102, each core particle 102 can have a similar particle size. In additional or alternative embodiments, the particle size distribution of the core particles can be normally distributed. In other embodiments, the particle size distribution of the core particles can be bimodal. In additional or alternative embodiments, the core particles 102 can be larger secondary particles composed of smaller primary particles. Specifically, each secondary particle can include a plurality of primary particles.

[0051] In some embodiments, the core particles 102 can have a surface that includes one or more surface structures 110. Such surface structures 110 can be openings or cracks within the surface of the core particles 102. The size and / or depth of the surface structures 110 can vary. Specifically, in some embodiments, the surface structures 110 can be irregular such that the surface structures 110 can have different shapes and sizes. It can be appreciated that the surface structures 110 increase the surface area of the core particles 102.

[0052] The core particles 102 can be coated with a surface coating 104. The surface coating 104 can provide at least a partial barrier interface such that the entire surface of the core particles 102 can not be completely directly exposed to the electrolyte in the battery. As such, in some embodiments, the surface coating 104 can completely or substantially completely cover the surface of the core particles 102.

[0053] The surface coating 104 can include at least lithium supplement material particles 106. Among others, the lithium supplement material particles 106 can be in direct contact with each other or can be in direct contact with the core particles 102. The lithium supplement material particles 106 can include any material that can undergo a decomposition process and result in at least one lithium ion product. For example, the lithium supplement material particles 106 can include lithium peroxide, lithium aluminum oxide (LAO), lithium iron oxide (LFO), lithium oxide, lithium nitride, lithium sulfide, lithium azide, a conversional prelithiation reagent, or a combination thereof. In some embodiments, the lithium supplement material particles 106 can include lithium peroxide. In other embodiments, the lithium supplement material particles 106 can include a conversional prelithiation reagent, where the conversional prelithiation reagent can be, for example, a mixture of one or more metals of Co, Fe, Mn, Ni, Cu, Pb, Ru, and Mo with one or more of Li2O, LiF, and Li2S, such that a conversion reaction can release lithium ions and a corresponding metal compound (e.g., an oxide, a fluoride, a sulfide of the one or more metals). A thorough and sufficient mixing can be needed to reduce a conversion voltage of the conversion reaction to a desired value.

[0054] Further, the battery cell can include the coated positive active material particles 100, where the lithium supplement material particle component can be lithium peroxide. As shown below in reference to Figures 3-5 Further, as described below, the use of lithium peroxide as the lithium supplement material particle component can be paired with a CC (e.g., 108) to catalyze the decomposition process. In other words, without the CC, lithium peroxide can be difficult to decompose.

[0055] In other embodiments, the lithium supplement material particles 106 can include anti-fluorite structure materials, such as LAO and / or LFO. In certain embodiments, anti-fluorite structure materials can be used as lithium supplement materials over conventional materials because the anti-fluorite structure materials can be more easily decomposed and release lithium ions at voltages corresponding to actual battery environments as compared to other lithium supplement materials, such as lithium peroxide. For example, in a battery cell operating in a conventional voltage window between 3 V and 4.3 V, the anti-fluorite type of material can easily release stored lithium ions and not accept the lithium ions upon discharge, thereby adding capacity to the battery cell to compensate for the loss of lithium ions in the first charge / discharge cycle. Furthermore, in a battery cell including coated positive active material particles 100 where the lithium supplement material composition can be LAO, CC can not be needed. During the decomposition of LAO, lithium ions can be provided to prelithiate the anode. Furthermore, the residual products from the decomposition process can substantially remain on the surface of the core particle 102, such that an aluminum-containing layer (e.g., from LAO) or an iron-containing layer (e.g., from LFO) can thereby coat the surface of the core particle 102. In embodiments employing LAO as the lithium supplement material component, an aluminum-containing layer, which can include aluminum oxide or alumina or AI2O3, can further improve the safety and cycle stability of the battery cell.

[0056] The average particle size of the lithium supplement material particles 106 can be substantially similar to or smaller than the average particle size of the core particles 102. In some embodiments, a relationship can be formed between the core particles 102 and the lithium supplement material particles 106 such that each lithium supplement material particle 106 can be smaller than each core particle 102. The lithium supplement material particles 106 can have an average particle size of at most 1 pm. In some embodiments, the average particle size of the lithium supplement material particles 106 can be in a range between 0.01 pm and 1 pm. In other embodiments, the average particle size of the lithium supplement material particles 106 can be in a range between 0.1 pm and 1 pm. In other embodiments, the average particle size of the lithium supplement material particles 106 can be in a range between 0.3 pm and 1 pm. In other embodiments, the average particle size of the lithium supplement material particles 106 can be in a range between 0.1 pm and 0.5 pm. In other embodiments, the average particle size of the lithium supplement material particles 106 can be in a range between 0.1 pm and 0.3 pm. In other embodiments, the average particle size of the lithium supplement material particles 106 can be in a range between 0.5 pm and 1 pm. In other embodiments, the lithium supplement material particles 106 can be nanoscale (e.g., the average particle size of the lithium supplement material particles 106 can be less than 1 pm). In additional or alternative embodiments, each lithium supplement material particle 106 can have a substantially similar particle size to each other lithium supplement material particle 106. In some embodiments, a relationship can be formed between the lithium supplement material particles 106 such that each lithium supplement material particle 106 can have a similar particle size. In additional or alternative embodiments, the PSD of the lithium supplement material can be normally distributed. In additional or alternative embodiments, the PSD of the lithium supplement material can be bimodal.

[0057] The surface coating 104 can further include CC particles 108. The CC particles 108 can include any material that catalyzes the decomposition process of the lithiation material particles 106. As such, the CC particles 108 can be coated on the core particles 102 simultaneously with the lithiation material particles 106. Among other things, the CC particles 108 can be in direct contact with each other, can be in direct contact with the lithiation material particles 106, and / or can be in direct contact with the core particles 102. The CC particles 108 can include any material that is not consumed in the first charge cycle. In some embodiments, the CC particles 108 can include a lithium-based ACC, where the ACC can be any lithium compound that reversibly releases and accepts lithium ions during a charge cycle and catalyzes the decomposition process of the lithiation material particles 106. In some embodiments, the CC particles 108 can include other catalytic materials that can not contribute to the specific capacity of the cathode in which the CC particles 108 are incorporated. In some embodiments, the CC particles 108 can act as a secondary lithiation material. Further, the CC particles 108 can include a compound of a transition metal with partially occupied d and / or f orbitals that is capable of enabling electron transitions and lowering the activation energy in the decomposition process of the lithiation material particles 106. The ACC can act as a catalyst before Li is released during charging, or after partial or complete release of Li during charging. In the latter case, the delithiated homolog (which can have a different chemical formula and / or structure) of the ACC can be considered the actual CC that catalyzes the decomposition reaction of the lithiation material. For example, the CC particles 108 can include LMFP, lithium iron phosphate (LFP), lithium vanadium fluorophosphate (LVFP), NMC, NCA, LAO, LFO, or combinations thereof. For example, but not limited to, the NMC can be NMC111, NMC523, NMC622, NMC811, or combinations thereof. Further, the NMC can be a single phase crystal, or the NMC can be in a polycrystalline or amorphous form. In some embodiments, the CC particles 108 can consist of only one chemical component. In additional or alternative embodiments, the CC particles 108 can include a metal oxide, such as cobalt tetroxide (C03C ). In additional or alternative embodiments, the components of the CC particles 108 and the core particles 102 can be indistinguishable, such that each of the CC particles 108 and the core particles 102 have similar chemical components. For example, the core particles 102 can include a lithium mixed metal oxide, the CC particles 108 can include a lithium mixed metal oxide, where the lithium mixed metal oxide of the core particles 102 can be the lithium mixed metal oxide of the CC particles 108. In additional or alternative embodiments, the components of the CC particles 108 and the core particles 102 can be different. For example, the core particles 102 can include a lithium mixed metal oxide, the CC particles 108 can include a lithium mixed metal oxide, where the lithium mixed metal oxide of the core particles 102 can be different from the lithium mixed metal oxide of the CC particles 108.

[0058] Further, the battery cell can include coated positive active material particles 100 that include lithium supplement material particles 106 and CC particles 108, where the composition of the CC particles 108 can be one or more of LMFP, LFP, LVFP, and LAO. The CC particles 108 can catalyze the decomposition process of the lithium supplement material particles 106. Further, the CC particles 108 can also decompose during the catalysis. In such embodiments, the CC particles 108 can act as a catalyst before or after decomposition. When the CC particles 108 act as a catalyst after decomposition, the actual CC can be a decomposition product from the decomposition reaction of the CC particles 108. Residual products originating from the lithium supplement material particles 106 and / or the CC particles 108 can substantially remain on the surface of the core particles 102, such that a residual layer can thereby coat the surface of the core particles 102. The residual layer can further improve the safety, capacity, and cycle stability of the battery. When paired with the residual layer described above, further improvements to the first cycle discharge capacity (FDC) and cycle performance of the battery cell attributed to anode prelithiation can provide a double performance advantage. In embodiments where the CC particles 108 include LAO, the decomposition process of the CC particles 108 can leave behind aluminum-containing residuals, such as aluminum oxides or aluminum oxide or AI2O3, which are known to those skilled in the art to be advantageous to the safety and performance of the battery.

[0059] It should be understood that LAO is generally considered to be a lithium supplement material. However, in certain embodiment configurations, LAO can also act as a CC. For example, the CC particles 108 can include LAO, and the lithium supplement material particles 106 can include lithium peroxide. With such an exemplary configuration, the CC particles 108, i.e., LAO, can contribute lithium ions to prelithiate the anode while still providing the advantages attributed to aluminum-containing residuals described above. It can be appreciated that other LMOs, such as LFO, can additionally or alternatively be used as active materials, lithium supplement materials, and / or CCs.

[0060] In embodiments where the CC particles 108 include LMFP or LVFP and the core particles 102 include NMC, the cycle stability of the battery can not be significantly reduced, and can have improved safety performance and capacity. As such, the reduction in energy density due to the presence of the CC particles 108 can be mitigated by performance benefits such as improved capacity. Specifically, the CC particles 108 having a composition such as LMFP or LVFP can release and accept lithium ions within the operating voltage range of the battery, such that the CC particles 108 can simultaneously act as an active component of the battery.

[0061] The CC particles 108 can have an average particle size that is substantially similar to or smaller than the average particle size of the lithium supplement material particles 106. In some embodiments, a relationship can be formed between the lithium supplement material particles 106 and the CC particles 108 such that each CC particle 108 can be smaller than each lithium supplement material particle 106. Further, the CC particles 108 can have an average particle size that is substantially similar to or smaller than the average particle size of the core particles 102. In some embodiments, a relationship can be formed between the core particles 102 and the CC particles 108 such that each CC particle 108 can be smaller than each core particle 102. The CC particles 108 can have an average particle size of at most 5 pm. In some embodiments, the average particle size of the CC particles 108 can be at most 1 pm. In other embodiments, the average particle size of the CC particles 108 can be in a range between 0.01 pm and 1 pm. In other embodiments, the average particle size of the CC particles 108 can be in a range between 0.1 pm and 1 pm. In other embodiments, the average particle size of the CC particles 108 can be in a range between 0.3 pm and 1 pm. In other embodiments, the average particle size of the CC particles 108 can be in a range between 0.5 pm and 1 pm. In other embodiments, the average particle size of the CC particles 108 can be in a range between 0.1 pm and 0.5 pm. In other embodiments, the average particle size of the CC particles 108 can be in a range between 0.1 pm and 0.4 pm. In other embodiments, the CC particles 108 can be nanoscale (e.g., the average particle size of the CC particles 108 can be less than 1 pm). In additional or alternative embodiments, the particle size of each CC particle 108 can be substantially similar to the particle size of each other CC particle 108. In some embodiments, a relationship can be formed between the CC particles 108 such that each CC particle 108 can have a similar particle size. In additional or alternative embodiments, the PSD of the CC can be normally distributed. In additional or alternative embodiments, the PSD of the CC can be bimodal.

[0062] The lithium supplement material particles 106 and / or CC particles 108 can be held in place via van der Waals molecular forces and / or mechanical forces between each other and / or with the core particles 102 and the surface structures 110 thereon. In addition to or instead of the van der Waals molecular forces and / or mechanical forces, stronger forces can be employed, for example, through a heating or annealing process. The stronger forces can include one or more of hydrogen bonds, ionic bonds, covalent bonds, and the like. In some embodiments, the stronger forces can include binding with or annealing to a binder. The binder can be disposed between the core particles 102, the lithium supplement material particles 106, the CC particles 108, and / or the passivation layer 112. In some embodiments, the binder can be a polymer, such as polyvinylidene fluoride (PVDF), polyvinylpyrrolidone (PVP), polyethylene oxide (PEO), or polyimide (PI). In embodiments where the binder included in the surface coating 104 is PVDF, the PVDF can gel and facilitate the formation of a three-dimensional network of structures by fixing the lithium supplement material particles 106 and / or CC particles 108 in place, further enhancing the surface coating 104. It should be appreciated that the beneficial effects attributed to the PVDF within the surface coating 104 can be contrasted with the inclusion of PVDF as a separate binder between the coated cathode active material particles 100 in the final formed cathode slurry, as gelling can not be desirable during cathode slurry manufacturing.

[0063] In some embodiments, the surface coating 104 includes each of lithium supplement material particles 106 and CC particles 108. In some embodiments, there can be a greater weight of lithium supplement material particles 106 than CC particles 108. A minimum amount of CC particles 108 required for the decomposition process of the catalytic lithium supplement material particles 106 can be selected. In some embodiments, there can be no or substantially no CC particles 108. In other embodiments, the weight ratio of lithium supplement material particles 106 to CC particles 108 can be about 100: 1, 50: 1, 20: 1, 15: 1, 10: 1, 9: 1, 8: 1, 7: 1, 6: 1, 5: 1, 4: 1, 3: 1, 2: 1, or 1.5: 1. In some embodiments, the weight ratio of lithium supplement material particles 106 to CC particles 108 can be about 1: 1, so there is substantially an equal amount of lithium supplement material particles 106 to CC particles 108. When the weight ratio of lithium supplement material particles 106 to CC particles 108 is about 1: 1, the average particle size and surface area of CC particles 108 can be substantially similar to those of lithium supplement material particles 106, respectively. In some embodiments, there can be a greater weight of CC particles 108 than lithium supplement material particles 106. In this way, the voltage required for the decomposition process of lithium supplement material particles 106 can be reduced. In some embodiments, the weight ratio of lithium supplement material particles 106 to CC particles 108 can be about 1:0.5, 1: 1, 1:2, 1:3, 1:4, 1:5, 1:6, 1:7, 1:8, 1:9, 1:10, 1:15, 1:20, 1:50, or 1:100. In this way, in some embodiments, the weight ratio of lithium supplement material particles 106 to CC particles 108 can be between 100: 1 and 1: 100. In other embodiments, the weight ratio can be between 50: 1 and 1:50. In other embodiments, the weight ratio can be between 20: 1 and 1:20. In other embodiments, the weight ratio can be between 15: 1 and 1: 15. In other embodiments, the weight ratio can be between 10: 1 and 1: 10. In other embodiments, the weight ratio can be between 9: 1 and 1:9. In other embodiments, the weight ratio can be between 8: 1 and 1:8. In other embodiments, the weight ratio can be between 7: 1 and 1:7. In other embodiments, the weight ratio can be between 6: 1 and 1:6. In other embodiments, the weight ratio can be between 5: 1 and 1:5. In other embodiments, the weight ratio can be between 4: 1 and 1:4. In other embodiments, the weight ratio can be between 3: 1 and 1:3. In other embodiments, the weight ratio can be between 2: 1 and 1:2. In other embodiments, the weight ratio can be between 1.5: 1 and 1: 1.5. In other embodiments, the weight ratio can be between about 1.5: 1 and about 1:4. In other embodiments, the weight ratio can be between about 1:0.7 and about 1:4.In one embodiment, the CC particles 108 can be LMFP and the weight ratio of the lithium supplement material particles 106 to the CC particles 108 can be 1 :4. In another embodiment, the CC particles 108 can be Co3O4and the weight ratio of the lithium supplement material particles 106 to the CC particles 108 can be 1.5: 1. Further, the weight ratio of the lithium supplement material particles 106 to the CC particles 108 can be based on the anode composition and / or the extent of irreversible capacity loss that needs to be compensated for.

[0064] The surface coating 104 can be present in the active material in an amount greater than 0 wt% and less than 50 wt%. In some embodiments, the surface coating 104 can be present in the active material in an amount greater than 0.1 wt% and less than 50 wt%. In other embodiments, the surface coating 104 can be present in the active material in an amount greater than 0.1 wt% and less than 30 wt%. In other embodiments, the surface coating 104 can be present in the active material in an amount greater than 0.1 wt% and less than 10 wt%. In other embodiments, the surface coating 104 can be present in the active material in an amount greater than 0.1 wt% and less than 5 wt%.

[0065] In some embodiments, the lithium supplement material particles 106 and / or the CC particles 108 can adhere to and / or within the surface structures 110 via Van der Waals molecular forces and / or mechanical forces. As such, the lithium supplement material particles 106 and / or the CC particles 108 can each have a particle size that is complementary to the size of the corresponding surface structure 110, such that the lithium supplement material particles 106 and / or the CC particles 108 can be partially fixed in the surface structure 110. In some embodiments, the lithium supplement material particles 106 and / or the CC particles 108 can be ground to a preselected average particle size. The preselected average particle size of the lithium supplement material particles 106 and / or the CC particles 108 is such that the particles remain on and partially within the surface structure 110 on the surface of the core particle 102 having a complementary size. In other embodiments, the lithium supplement material particles 106 and / or the CC particles 108 can have substantially different particle sizes, such that the particles can be retained in the corresponding surface structure 110 of matching size.

[0066] The surface coating 104 can be composed of high density of lithium supplement material particles 106 and / or CC particles 108, such that the surface coating 104 can be considered uniform and continuous. Further, the thickness of the surface coating 104 can vary depending on the location of the lithium supplement material particles 106 and / or CC particles 108 on or within the surface of the core particle 102. In some embodiments, the maximum thickness can be considered to be the approximate particle diameter of the lithium supplement material particles 106 and / or CC particles 108. In other words, the lithium supplement material particles 106 and CC particles 108, alone or in combination, can be arranged as a monolayer, where the maximum thickness of the surface coating 104 of the core particle 102 can correspond to the maximum particle diameter of the lithium supplement material particles 106 and / or CC particles 108.

[0067] In other embodiments, the surface coating 104 can be multi-layered in thickness. For example, in some embodiments, multiple layers of the surface coating 104 can exist on the surface of the core particle 102. The thickness of the surface coating 104 can be no more than about 3 particle thicknesses, where the particles can include lithium supplement material particles 106 and / or CC particles 108. In additional or alternative embodiments, the thickness of the surface coating 104 can be no more than 3 pm.

[0068] The surface coating 104 can be applied to the core particle 102 by a variety of methods (as described below with reference to Figures 6-8 In some methods, one or more properties of the core particle 102, lithium supplement material particles 106, and / or CC particles 108 can be selectively controlled based on the method of preparation. For example, the average particle diameter of each of the lithium supplement material particles 106 and / or CC particles 108 can be optimized for optimal electrochemical performance.

[0069] The surface coating 104 can be further coated with a passivation layer 112 such that the surface coating 104 can be disposed between the core particle 102 and the passivation layer 112. The passivation layer 112 can be insoluble in processing solvents and electrolytic solvents. Further, the passivation layer 112 can be ionically and electronically conductive. For example, the passivation layer 112 can include a polymer, carbon, ceramic, zeolite, or a hybrid coating. In some embodiments, the passivation layer 112 can be a polymer that can be partially or fully dissolved in electrolytic solvents. In some embodiments, the polymer coating can be low molecular weight, for example less than 100,000 Da, and can be applied at low concentrations. In additional or alternative embodiments, the polymer coating can include ionically conductive polymers such as poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS), cross-linked polyethylene glycol, cross-linked polyvinyl alcohol, PI, sodium carboxymethylcellulose, sodium polyacrylate, or combinations thereof. In additional or alternative embodiments, the polymer coating can include polymethyl methacrylate (PMMA), PEO, or combinations thereof. The polymer coating can improve the FCE of the battery cell, but the polymer can further reduce the electrical conductivity of the coated positive active material particle 100. Accordingly, a highly structured and / or conductive carbon can be included in a composite or hybrid coating. In some embodiments, the conductive carbon can include one or more of vapor grown carbon fibers and Super P TM In one embodiment, to ensure a percolation network, a readily dispersible conductive carbon such as Super P TM In additional or alternative embodiments, the form of the carbon coating can be amorphous. Further, the carbon coating can incorporate a metal acetylide, where the metal can be, for example, but not limited to, one or more of Cu, Al, Mg, Mn, Ni, and Co, and the metal can be selected based on optimal electrical conductivity and thermal stability. The metal can be further selected to be compatible with the voltage extremes of the battery cell that includes the coated positive active material particle 100. In additional or alternative embodiments, the zeolite coating can have a highly stable structure and a controllable pore size. Further, the zeolite coating can provide a catalytic benefit. The carbon coating can include graphene (hydrophobic) nanoplatelets in a cladding layer structure that can be selectively permeable to enable the transfer of O2 and act as a barrier to moisture. Such a graphene coating can also improve electrical conductivity. In some embodiments, the passivation layer 112 can be achieved by high energy mechanical mixing without additional binders.

[0070] The passivation layer 112 can have a thickness of up to 1 pm. In some embodiments, the passivation layer 112 can have a thickness in a range of 0.1 pm to 1 pm. In other embodiments, the passivation layer 112 can have a thickness in a range of 0.3 pm to 1 pm. In other embodiments, the passivation layer 112 can have a thickness in a range of 0.5 pm to 1 pm. In other embodiments, the passivation layer 112 can have a thickness in a range of 0.1 pm to 0.5 pm. In other embodiments, the passivation layer 112 can have a thickness of less than 0.1 pm.

[0071] The passivation layer 112 can uniformly, continuously, and conformally coat the surface coating 104, such that the surface coating 104 can be considered to be completely covered by the passivation layer 112. In additional or alternative embodiments, the passivation layer 112 can include particles that discretely coat the surface coating 104. In this manner, the passivation layer 112 can act as a barrier layer, such that the passivation layer 112 can mitigate undesirable side reactions between the core particle 102, the lithium supplement material particle 106, and / or the CC particle 108 and the electrolyte in the battery. Further, the passivation layer 112 can protect the core particle 102, the lithium supplement material particle 106, and / or the CC particle 108 from air and / or moisture, such that the coated cathode active material particle 100 can be stable in air and / or moisture. It is particularly beneficial that the passivation layer 112 can be semi-permeable, such that the passivation layer 112 can allow certain chemical compounds (e.g., lithium ions and oxygen) to pass from within the passivation layer 112 to outside of the passivation layer 112, while still substantially protecting and retaining other compounds or nanoscale particles thereof inside the passivation layer 112. Further, the passivation layer composition can also provide higher efficiency and conductivity for the coated cathode active material particle 100 at the interface with the electrolyte in the battery. As such, the surface coating 104 in combination with the passivation layer 112 can provide significant advantages over standard slurry coatings, which can not have controls in place to prevent undesirable side reactions with water contaminants during processing. Further, the substantial costs associated with atmosphere control by vacuum, inert gas, or transport systems during manufacturing of such standard configurations can be avoided.

[0072] Referring now to FIG. 2, Figure 2 a coated cathode active material particle 200 is shown. As such, the coated cathode active material particle 200 can include a core particle 202. The core particle 202 can be Figure 1 the core particle 102.

[0073] The core particle 202 can have a surface coating 204, where the surface coating 204 can include one or more of a lithium supplement material particle 206, a CC particle 208, and a binder 211. The lithium supplement material particle 206 and the CC particle 208 can be Figure 1lithium supplement material particles 106 and CC particles 108. Figure 2 The surface coating 204 shown in FIG. 2B is a material and features disposed between the surface of the core particle 202 and the maximum extent 205, where the maximum extent 205 is shown by the dashed line. The surface coating 204 can be Figure 1 One or more embodiments of the surface coating 104 of FIG. 1. For example, the lithium supplement material particles 206 and / or CC particles 208 can be held in place by van der Waals molecular forces and / or mechanical forces between each other and / or between the core particle 202 and the surface structure 210 thereon. In addition to or instead of the van der Waals molecular forces and / or mechanical forces, stronger forces can be employed, for example, through a heating or annealing process. The stronger forces can include one or more of hydrogen bonds, ionic bonds, covalent bonds, and the like.

[0074] In some embodiments, the stronger forces can include bonding with or annealing to a binder 211. The binder 211 can be disposed between the core particle 202, the lithium supplement material particles 206, and / or the CC particles 208, such that the surface coating 204 can be formed on the core particle 202. In some embodiments, the binder can be a polymer that is soluble in an organic solvent, such as N-2-methylpyrrolidone (NMP). The binder 211 can include, for example, PVDF, PVP, PEO, a cellulose derivative, or a linear, semi-aromatic, or aromatic PI. In one embodiment, the binder 211 can include an aromatic polyimide that is cross-linkable through a heat treatment at about 350 °C. In this way, the binder 211 can impart increased partial electrical conductivity to a battery containing the coated cathode active material particle 200.

[0075] In some embodiments, the surface coating 204 includes each of lithium supplement material particles 206 and CC particles 208. In some embodiments, the weight of lithium supplement material particles 206 can be greater than CC particles 208. In this way, the minimum amount of CC particles 208 required to catalyze the decomposition process of lithium supplement material particles 206 can be selected. In some embodiments, CC particles 208 can be absent or substantially absent. In other embodiments, the weight ratio of lithium supplement material particles 206 to CC particles 208 can be about 100: 1, 50: 1, 20: 1, 15: 1, 10: 1, 9: 1, 8: 1, 7: 1, 6: 1, 5: 1, 4: 1, 3: 1, 2: 1, or 1.5: 1. In some embodiments, the weight ratio of lithium supplement material particles 206 to CC particles 208 can be about 1: 1, such that lithium supplement material particles 206 can be present in substantially equal amounts to CC particles 208. When the weight ratio of lithium supplement material particles 206 to CC particles 208 is about 1: 1, the average particle diameter and surface area of CC particles 208 can be substantially similar to those of lithium supplement material particles 206, respectively. In some embodiments, the weight of CC particles 208 can be greater than lithium supplement material particles 206. In this way, the voltage required for the decomposition process of lithium supplement material particles 206 can be reduced. In some embodiments, the weight ratio of lithium supplement material particles 206 to CC particles 208 can be about 1:0.5, 1: 1, 1:2, 1:3, 1:4, 1:5, 1:6, 1:7, 1:8, 1:9, 1:10, 1:15, 1:20, 1:50, or 1:100. In this way, in some embodiments, the weight ratio of lithium supplement material particles 206 to CC particles 208 can be between 100: 1 and 1: 100. In other embodiments, the weight ratio can be between 50: 1 and 1:50. In other embodiments, the weight ratio can be between 20: 1 and 1:20. In other embodiments, the weight ratio can be between 15: 1 and 1: 15. In other embodiments, the weight ratio can be between 10: 1 and 1: 10. In other embodiments, the weight ratio can be between 9: 1 and 1:9. In other embodiments, the weight ratio can be between 8: 1 and 1:8. In other embodiments, the weight ratio can be between 7: 1 and 1:7. In other embodiments, the weight ratio can be between 6: 1 and 1:6. In other embodiments, the weight ratio can be between 5: 1 and 1:5. In other embodiments, the weight ratio can be between 4: 1 and 1:4. In other embodiments, the weight ratio can be between 3: 1 and 1:3. In other embodiments, the weight ratio can be between 2: 1 and 1:2. Further, the weight ratio of lithium supplement material particles 206 to CC particles 208 can be based on the composition of the anode and / or the extent of irreversible capacity loss that is desired to be compensated for.

[0076] The surface coating 204 can be present in the active material in an amount greater than 0 wt% and less than 50 wt%. In some embodiments, the surface coating 204 can be present in the active material in an amount greater than 0.1 wt% and less than 50 wt%. In other embodiments, the surface coating 204 can be present in the active material in an amount greater than 0.1 wt% and less than 30 wt%. In other embodiments, the surface coating 204 can be present in the active material in an amount greater than 0.1 wt% and less than 10 wt%. In other embodiments, the surface coating 204 can be present in the active material in an amount greater than 0.1 wt% and less than 5 wt%.

[0077] In some embodiments, the lithium supplement material particles 206 and / or CC particles 208 can adhere to and / or within the surface structures 210 via Van der Waals molecular forces and / or mechanical forces. As such, the particle size of each of the lithium supplement material particles 206 and / or CC particles 208 can complement the size of the corresponding surface structure 210, such that the lithium supplement material particles 206 and / or CC particles 208 can be partially immobilized in the surface structure 210. In some embodiments, the lithium supplement material particles 206 and / or CC particles 208 can be ground to a preselected average particle size. The preselected average particle size of the lithium supplement material particles 206 and / or CC particles 208 can enable the particles to be retained on and partially within the surface structure 210 having a complementary size on the surface of the core particle 202. In other embodiments, the lithium supplement material particles 206 and / or CC particles 208 can have substantially different sizes, such that the particles can be retained in the corresponding surface structure 210 matching the size.

[0078] The surface coating 204 can be composed of high density lithium supplement material particles 206 and / or CC particles 208, such that the surface coating 204 can be considered uniform and continuous. In some embodiments, the surface coating 204 can further include a binder 211. Further, the thickness of the surface coating 204 can vary depending on the location of the lithium supplement material particles 206 and / or CC particles 208 on or within the surface of the core particle 202. In some embodiments, at the maximum extent 205, the thickness of the surface coating 204 can be considered the approximate particle size of the lithium supplement material particles 206 and / or CC particles 208. In other words, the lithium supplement material particles 206 and CC particles 208 can be arranged individually or in combination as a monolayer, wherein the maximum thickness of the surface coating 204 of the core particle 202 can correspond to the maximum particle size of the lithium supplement material particles 206 and / or CC particles 208.

[0079] In other embodiments, the surface coating 204 can be multi-layered at the maximum extent 205. For example, in some embodiments, a plurality of layers of the surface coating 204 can be present on the surface of the core particle 202. The thickness of the surface coating 204 can be no more than about 3 particle thicknesses, where the particles can include lithium supplement material particles 206 and / or CC particles 208. In additional or alternative embodiments, the thickness of the surface coating 204 can be no more than 3 pm.

[0080] The surface coating 204 can be applied to the core particle 202 by a variety of methods (described below with reference to Figure 7 An example method is described. In some methods, one or more properties of the core particle 202, lithium supplement material particles 206, CC particles 208, and / or binder 211 can be selectively controlled based on the method of preparation. For example, the average particle size of each of the lithium supplement material particles 206 and / or CC particles 208 can be optimized for optimal electrochemical performance. In some methods, surface modification or surface grafting can be employed to achieve optimal interaction between the core particle 202 and the lithium supplement material particles 206, CC particles 208, and / or binder 211.

[0081] In some embodiments, the coated cathode active material particle 200 can be included in a battery that includes at least an electrolyte. Further, the surface coating 204 can be multi-layered and can include at least the binder 211. In this way, the outer layer of the lithium supplement material particles 206 and / or CC particles 208 and the binder 211 can protect the core particle 202 and the inner layer of the lithium supplement material particles 206 and / or CC particles 208 from air, moisture, and other impurities in the electrolyte, thereby mitigating unwanted side reactions.

[0082] Figures 3-5 Embodiments of a method are shown. Each embodiment of the method is schematically shown as a first coated cathode active material being decomposed into a second coated cathode active material by a decomposition process, where a first and second decomposition product have been released and a residue is left behind. The first and second coated cathode active materials can include a plurality of similar components. The second coated cathode active material can differ from the first coated cathode active material in that one or more components of the first coated cathode active material have been decomposed by the decomposition process.

[0083] Referring now to Figure 3 , a method 300 is shown. A first coated cathode active material 301 can be the coated cathode active material particle 100 of Figure 1 In alternative embodiments of the method 300, not shown, the first coated cathode active material 301 can be the coated cathode active material particle 200 of Figure 2The first coated positive electrode active material 301 can include coated positive electrode active material particles 200. As such, the first coated positive electrode active material 301 can include core particles 302. The core particles 302 can have a surface coating 304, where the surface coating 304 can include first lithiu m supplement material particles 306a, second lithium supplement material particles 306b, and CC particles 308. A passivation layer 312 can coat the core particles 302, such that the surface coating 304 can be between the core particles 302 and the passivation layer 312. One or more of the first lithium supplement material particles 306a, the second lithium supplement material particles 306b, and / or the CC particles 308 can have a composition of one or more materials. In one embodiment, the first lithium supplement material particles 306a can be lithium peroxide, lithium oxide, LAO, LFO, or a combination thereof. Further, the second lithium supplement material particles 306b can be lithium peroxide, lithium oxide, LAO, or a combination thereof. Further, the CC particles 308 can be one or more of NMC, LMFP, and cobalt tetroxide, where the NMC can be one or more of NMC1 1 1, NMC523, NMC622, and NMC81 1. The composition of the first lithium supplement material particles 306a can be different than the composition of the second lithium supplement material particles 306b. The passivation layer 312 can be semi-permeable, such that at least a portion of the decomposition products of the first and second lithium supplement material particles 306a and 306b can pass through the passivation layer 312.

[0084] One or both of the first and second lithium supplement material particles 306a and 306b can decompose through a decomposition process 320. The decomposition process 320 can include the CC particles 308 catalyzing the decomposition process of one or both of the first and second lithium supplement material particles 306a and 306b, such that at least two decomposition products can be produced. The decomposition products can be derived from one or both of the first and second lithium supplement material particles 306a and 306b. As referenced above with respect to FIG. 3, in some embodiments, one or both of the first and second lithium supplement material particles 306a and 306b can undergo the decomposition process 320 substantially without the CC particles 308, for example when one of the first and second lithium supplement material particles 306a and 306b is LAO or LFO. Figure 1

[0085] ​After decomposition process 320, the second coated positive electrode active material 331 remains, releasing the first and second decomposition products 332 and 334. As shown, both the first and second lithium replenishing material particles 306a and 306b can be decomposed through decomposition process 320, thus leaving virtually no residue of the first and second lithium replenishing material particles 306a and 306b in the second coated positive electrode active material 331. Furthermore, one or both of the first and second lithium replenishing material particles 306a and 306b have decomposed, leaving residue 336 in the second coated positive electrode active material 331 and retained in the surface coating 304. As shown, CC particles 308 can remain unchanged during decomposition process 320. The first and second decomposition products 332 and 334 are shown as having substantially penetrated the semi-permeable passivation layer 312 as described above. Furthermore, the first and second decomposition products 332 and 334 can be released in a highly dispersed manner. Additionally, refer to, for example, the following... Figures 6-8 The described manufacturing methods, compared to conventional slurry coating methods, can prevent significant agglomeration of the first and second lithium-replenishing material particles 306a and 306b, thereby ensuring uniform dispersion of the particles. Due to this method and coating structure, voids 338 can be retained in the second-coated positive electrode active material 331 after the decomposition process 320. However, voids 338 may already exist at least partially as inter-particle gaps within the core particle 302 before the coating treatment of the core particle 302. In embodiments where at least one of the first and second lithium-replenishing material particles 306a and 306b includes LAO or LFO, solid decomposition products (e.g., residue 336), such as one or more of LiAlO2, LiFeO2, Al2O3, and Fe2O3, may form after the decomposition process 320. Thus, most of the decomposition products from the first and second lithium-replenishing material particles 306a and 306b can be retained in the surface coating 304.

[0086] In one embodiment, the first lithium supplement material particles 306a can be one or more of lithium peroxide and lithium oxide, and the second lithium supplement material particles 306b can be LAO or LFO. Further, the method 300 can be performed within a battery cell that includes at least a cathode, an anode, and an electrolyte, where the cathode includes the first coated cathode active material 301 prior to the decomposition process 320. After the decomposition process 320, the first lithium supplement material particles 306a can decompose into the first decomposition product 332 and the second decomposition product 334. The second lithium supplement material particles 306b can decompose into the first decomposition product 332 and the residue 336. In some embodiments, the first decomposition product 332 can be lithium ions, which can travel from the cathode and through the passivation layer 312 to prelithiate the anode. The second decomposition product 334 can be oxygen, which can travel through the passivation layer 312 and then be released from the battery cell, for example, via a compressive rolling of the battery cell. The residue 336 can be an aluminum-containing residue, such as an aluminum oxide, aluminum oxide, or AI2O3, which can improve the safety, capacity, and cycle stability of the battery cell. Additionally or alternatively, the residue 336 can be an iron-containing residue.

[0087] The described method 300 is one example of a decomposition process 320. In some embodiments, the second lithium supplement material particles 306b can be absent. In further or alternative embodiments, the CC particles 308 can be absent. In further or alternative embodiments, at least some of the first and second lithium supplement material particles 306a and 306b can be present in the second coated cathode active material 331 (e.g., due to incomplete decomposition process 320, either due to inherent physical and / or chemical conditions or controlled conditions, so as to intentionally leave at least some of the first and second lithium supplement material particles 306a, 306b unreacted for later activation and use). In further or alternative embodiments, there can be significantly more first and second lithium supplement material particles 306a and 306b than CC particles 308. In further or alternative embodiments, there can be significantly more CC particles 308 than first and second lithium supplement material particles 306a and 306b. In further or alternative embodiments, there can be significantly more first lithium supplement material particles 306a than second lithium supplement material particles 306b. In further or alternative embodiments, there can be significantly more second lithium supplement material particles 306b than first lithium supplement material particles 306a. In further or alternative embodiments, there can be no or substantially no residue 336 in the second coated cathode active material 331. In further or alternative embodiments, there can be no or substantially no second decomposition product 334 produced, or there can be no or substantially no second decomposition product 334 that travels through the passivation layer 312. In further or alternative examples, the residue 336 can include at least two different components.

[0088] Referring now toFigure 4 Method 400 is shown, wherein method 400 can be as described above in the reference. Figure 3 Another or alternative embodiment of the method 300. The first coated positive electrode active material 401 may be Figure 1 The coated positive electrode active material particles 100. In an alternative embodiment of method 400 (not shown), the first coated positive electrode active material 401 may be... Figure 2 The first coated positive electrode active material 401 may include core particles 402. Core particles 402 may have a surface coating 404, which may include lithium-supplementing material particles 406 and CC particles 408. A passivation layer 412 may be coated on the core particles 402 such that the surface coating 404 is disposed between the core particles 402 and the passivation layer 412. In one embodiment, the lithium-supplementing material particles 406 may be lithium peroxide or lithium oxide. Furthermore, the CC particles 408 may be one or more of NMC, LMFP, and cobalt tetroxide, wherein NMC may be one or more of NMC111, NMC523, NMC622, and NMC811. The passivation layer 412 may be semi-permeable, allowing decomposition products of the lithium-supplementing material particles 406 to pass through it.

[0089] The lithium replenishing material particles 406 can be decomposed through a decomposition process 420. The decomposition process 420 may include a decomposition of the lithium replenishing material particles 406 catalyzed by CC particles 408, thereby generating at least two decomposition products. These decomposition products may originate from the lithium replenishing material particles 406. In some embodiments, the lithium replenishing material particles 406 may undergo the decomposition process 420 substantially without CC particles 408.

[0090] After decomposition process 420, the second coated positive electrode active material 431 remains, releasing the first and second decomposition products 432 and 434. As shown, the lithium replenishing material particles 406 can be decomposed through decomposition process 420, so that essentially no lithium replenishing material particles 406 remain in the second coated positive electrode active material 431. As shown, CC particles 408 can remain unchanged during decomposition process 420, remaining in the surface coating 404. The first and second decomposition products 432 and 434 are shown to have substantially penetrated the semi-permeable passivation layer 412 as described above. Furthermore, the first and second decomposition products 432 and 434 can be released in a highly dispersed manner. Additionally, refer to the following, for example. Figures 6-8The manufacturing methods described can prevent significant agglomeration of the lithium supplement material particles 406 relative to common slurry coating methods, thereby allowing uniform dispersion of the lithium supplement material particles 406. As a result of this method, voids 438 can remain in the second coated positive active material 431 after the decomposition process 420. However, the voids 438 can have at least partially existed as interstitial spaces between primary particles within the core particles 402 prior to the coating process of the core particles 402.

[0091] In one embodiment, the lithium supplement material particles 406 can be one or more of lithium peroxide and lithium oxide. Further, the method 400 can be within a battery cell including at least a cathode, an anode, and an electrolyte, where the cathode includes the first coated positive active material 401 prior to the decomposition process 420. After the decomposition process 420, the lithium supplement material particles 406 can decompose into first and second decomposition products 432 and 434. In some embodiments, the first decomposition product 432 can be lithium ions, where the lithium ions can pass through the passivation layer 412 from the cathode to prelithiate the anode. Further, the CC particles 408 can be a lithiated compound, such as LMFP, which can reversibly release and accept lithium ions during a charge cycle. The CC particles 408 can act as a catalyst prior to or after releasing lithium ions during a charging process of a lithium ion battery. When the CC particles 408 act as a catalyst after partially or completely releasing lithium ions, the actual CC catalyzing the decomposition process can be partially or completely delithiated CC particles 408, which can have a different chemical formula and / or crystal structure. As such, the CC particles 408 can release and accept the first decomposition product 432. The second decomposition product 434 can be oxygen, where the oxygen can pass through the passivation layer 412 and then be released from the battery cell, for example, via a crimp of the battery cell.

[0092] The method 400 is one example of a decomposition process 420. In some embodiments, there can be no CC particles 408. In additional or alternative embodiments, there can be at least some lithium supplement material particles 406 in the second coated positive active material 431 (e.g., due to an incomplete decomposition process 420 due to inherent physical and / or chemical conditions or controlled conditions to intentionally leave at least some lithium supplement material particles 406 unreacted for later activation and use). In additional or alternative embodiments, there can be significantly more lithium supplement material particles 406 than CC particles 408. In additional or alternative embodiments, there can be significantly more CC particles 408 than lithium supplement material particles 406. In additional or alternative embodiments, there can be no or substantially no second decomposition product 434 produced, or there can be no or substantially no second decomposition product 434 passing through the passivation layer 412.

[0093] Reference is now made to Figure 5FIG. 5 shows a method 500 that can be the method 300 or the method 400 described above with reference to FIGS. 3 and 4, respectively. The first coated cathode active material 501 can be the coated cathode active material particle 100 described above with reference to FIG. 1. Figure 3 and 4 The method 300 or the method 400 described above. The first coated cathode active material 501 can be the coated cathode active material particle 100 described above with reference to FIG. 1. Figure 1 The method 300 or the method 400 described above. The first coated cathode active material 501 can be the coated cathode active material particle 100 described above with reference to FIG. 1. Figure 2 In this way, the first coated cathode active material 501 can include a core particle 502. The core particle 502 can have a surface coating 504, where the surface coating 504 can include lithium supplement material particles 506 and CC particles 508. A passivation layer 512 can coat the core particle 502 such that the surface coating 504 can be disposed between the core particle 502 and the passivation layer 512. In one embodiment, the lithium supplement material particles 506 can be one or more of lithium peroxide and lithium oxide. Further, the CC particles 508 can be one or more of LAO and LFO. The passivation layer 512 can be semi-permeable such that decomposition products of the lithium supplement material particles 506 can pass through the passivation layer 512.

[0094] The lithium supplement material particles 506 and / or the CC particles 508 can decompose through a decomposition process 520. The decomposition process 520 can include the CC particles 508 catalyzing the decomposition process of the lithium supplement material particles 506, whereby at least two decomposition products can be produced. The decomposition products can be derived from the lithium supplement material particles 506 and / or the CC particles 508. As discussed above with reference to FIG. 2, in some embodiments, the CC particles 508 (being LAO and / or LFO) can further act as a secondary lithium supplement material. In this way, the CC particles 508 can provide the dual benefit of catalyzing the decomposition process 520 and contributing lithium ions for pre-lithiating the anode. In some embodiments, the lithium supplement material particles 506 can undergo the decomposition process 520 substantially without the CC particles 508. Figure 1

[0095] After the decomposition process 520, a second coated cathode active material 531 is left over, releasing first and second decomposition products 532 and 534. As shown, the lithium supplement material particles 506 can decompose through the decomposition process 520 such that substantially none of the lithium supplement material particles 506 remain in the second coated cathode active material 531. Further, the CC particles 508 have decomposed such that first and second residuals 536a and 536b remain in the second coated cathode active material 531 and are retained in the surface coating 504. The first and second decomposition products 532 and 534 are shown as having substantially passed through the semi-permeable passivation layer 512 described above. Further, the first and second decomposition products 532 and 534 can be released in a highly dispersed manner. Further, for example, with reference to FIG. 2, the first and second decomposition products 532 and 534 can be lithium ions and oxygen, respectively. Figures 6-8 ​The manufacturing methods described can prevent significant agglomeration of the lithium supplement material particles 506 relative to common slurry coating methods, thereby allowing the lithium supplement material particles 506 to be uniformly dispersed. Due to this method and coating structure, voids 538 can remain in the second coated cathode active material 531 after the decomposition process 520. However, the voids 538 can have at least partially existed as interstitial spaces between primary particles within the core particles 502 prior to the coating process of the core particles 502. In embodiments where the CC particles 508 include LAO and / or LFO, after the decomposition process 520, solid decomposition products (e.g., the first and second residuals 536a and 536b) such as one or more of LiAlO2, LiFeO2, Al2O3, and Fe2O3 can be formed. Thus, a significant portion of the decomposition products from the CC particles 508 can remain in the surface coating 504.

[0096] In one embodiment, the lithium supplement material particles 506 can be one or more of lithium peroxide and lithium oxide. Further, the method 500 can be performed within a battery cell including at least a cathode, an anode, and an electrolyte, where the cathode includes the first coated cathode active material 501 prior to the decomposition process 520. Further, the CC particles 508 can be one or more of LAO and LFO. As such, the CC particles 508 can further act as a secondary lithium supplement material. After the decomposition process 520, the lithium supplement material particles 506 can decompose into first and second decomposition products 532 and 534. The CC particles 508 can decompose into the first decomposition product 532 as well as first and second residuals 536a and 536b. In some embodiments, the first decomposition product 532 can be lithium ions, where the lithium ions can pass through the passivation layer 512 from the cathode to prelithiate the anode. The second decomposition product 534 can be oxygen, where the oxygen can pass through the passivation layer 512 and then be released from the battery cell, for example via a crimp of the battery cell. The first and second residuals 536a and 536b can improve the safety, capacity, and cycle stability of the battery cell. In embodiments where the CC particles 508 include LAO, the first and second residuals 536a and 536b can be aluminum-containing residuals, for example LiAlO2 and Al2O3, respectively. In embodiments where the CC particles 508 include LFO, the first and second residuals 536a and 536b can be iron-containing residuals, for example LiFeO2 and Fe2O3, respectively.

[0097] The method 500 is one example of a decomposition process 520. In some embodiments, CC particles 508 can not be present. In additional or alternative embodiments, at least some of the lithium supplement material particles 506 can be present in the second coated cathode active material 531 (e.g., due to incomplete decomposition process 520, either due to inherent physical and / or chemical conditions or controlled conditions to intentionally leave at least some of the lithium supplement material particles 506 unreacted for later activation and use). In additional or alternative embodiments, significantly more lithium supplement material particles 506 can be present than CC particles 508. In additional or alternative embodiments, significantly more CC particles 508 can be present than lithium supplement material particles 506. In additional or alternative embodiments, there can be no or substantially no first and second residuals 536a and 536b in the second coated cathode active material 531. In additional or alternative embodiments, there can be no second residual 536b in the second coated cathode active material 531. In additional or alternative embodiments, no or substantially no second decomposition product 534 can be produced, or no or substantially no second decomposition product 534 can pass through the passivation layer 512.

[0098] Referring now to Figure 6 , a method 600 for manufacturing a coated cathode active material is shown, which includes coating a core powder with a lithium supplement material powder and a CC powder, and optionally a conductive carbon source and / or a binder. A passivation layer can then be applied. In some embodiments, the coated cathode active material can be a coated cathode active material particle 100 as described above with reference to Figures 3-5 , or a first coated cathode active material 301, 401, or 501 as described above with reference to Figure 7 .

[0099] At 602, a lithium supplement material powder can be milled to a first average particle size. The initial lithium supplement material powder can be commercially available. While a lithium supplement material powder can be synthesized for a high purity proof of concept embodiment, for commercial viability, a lithium supplement material powder produced by scaling up a process can be more suitable for the manufacture of a coated cathode active material. In some embodiments, the lithium supplement material powder can include lithium peroxide, LAO, LFO, lithium oxide, lithium nitride, or combinations thereof. Other lithium supplement materials can be further used as alternatives or in combination.

[0100] The initial particle size of the lithium replenishing material powder can be less than 1 μm. Alternatively, if the initial particle size of the lithium replenishing material powder is 1 μm or larger, the lithium replenishing material powder can be ground to a smaller predetermined first average particle size. Specifically, depending on the desired particle size, the lithium replenishing material powder can be ground for a predetermined time in an inert atmosphere by ball milling or atrition milling. In one embodiment, the lithium replenishing material powder can be ground for less than one hour to grind it into a finer powder with a first average particle size of less than 1 μm. In one embodiment, the volume can be achieved using an inert medium with a size less than 5 mm (e.g., The grinding media and lithium-supplementing material powder are semi-filled. Volumetric milling can be performed in less than an hour to produce finer lithium-supplementing material powder with a first average particle size of less than 1 μm. In some embodiments, the following can be used: The mill and the inert medium can be present in the volume in an amount of less than 35% by weight.

[0101] As the grinding duration of the lithium replenishment material powder increases, the first average particle size of the lithium replenishment material powder can decrease. Therefore, the first average particle size of the lithium replenishment material powder can be controlled by the grinding duration. The first average particle size of the lithium replenishment material powder can be determined by a bulk material analyzer. In some embodiments where the lithium replenishment material powder includes lithium peroxide, the first average particle size of the lithium replenishment material powder can be in the submicron range to improve the catalytic effect of lithium peroxide reduction / decomposition.

[0102] In 604 stainless steel, ACC powder can be ground to a second average particle size. ACC powder may include lithium-based compounds such as LMFP, LFP, LVFP, NMC, NCA, or combinations thereof, wherein NMC may be, for example, one or more combinations of NMC111, NMC523, NMC622, and NMC811. NMC may be a single-phase crystal, or NMC may be in polycrystalline or amorphous form. Other ACC may be used further as alternatives or in combination.

[0103] ACC powder can be ground to a predetermined second average particle size by ball milling or grinding. In some embodiments, ACC powder can be ground by grinding using an organic solvent (e.g., NMP). The ACC powder can be ground for a predetermined time depending on the desired particle size. In one embodiment, the ACC powder can be ground for less than one hour to form a finer powder with a second average particle size of less than 1 μm. As the grinding duration of the ACC powder increases, the second average particle size of the ACC powder can decrease. Therefore, the second average particle size of the ACC powder can be controlled by the grinding duration. As an example, the volume can be achieved using an inert medium (e.g., with a 1 mm diameter). The volume can then be milled at 1000 to 2000 rpm for a duration of 2 to 5 hours. In other embodiments, the volume can then be milled at 200 to 1000 rpm for a duration of 2 to 5 hours. The second average particle size of the ACC powder can be determined by a bulk analyzer. In some embodiments, the second average particle size of the ACC powder can be less than or equal to the first average particle size of the lithiation supplement material powder. In other embodiments, the second average particle size of the ACC powder can be greater than or equal to the first average particle size of the lithiation supplement material powder.

[0104] At 606, the core powder, the lithiation supplement material powder, the ACC powder, and the conductive carbon additive and / or binder can be mixed. The core powder can be LMO, lithium phosphate compound, or a combination thereof, but is not limited to these types of electrochemically active materials. As an example, the LMO can include NMC or NCA, where the NMC can be one or more of NMC111, NMC523, NMC622, and NMC811. The NMC can be a single phase crystal, or the NMC can be polycrystalline or amorphous form. The core powder can have an average particle size of 1 to 20 pm or 6 to 12 pm.

[0105] With each of the lithiation supplement material powder and the ACC powder as a direct conformal coating on the core powder, a drop in replacement powder for industry standard slurry coating processing can be provided. In some embodiments, no additional processing steps can be required when applying one or more additional layers to, for example, a preformed cathode.

[0106] In some embodiments, a dry blending / dry mixing process can be utilized, where the complementary sizes of the primary core particles, the lithiation supplement material particles, and the ACC particles, and optionally the conductive carbon and / or binder particles, can determine the effectiveness and extent of the coating. Energy dispersive X-ray spectroscopy / scanning electron microscopy (EDS / SEM) and XRD analysis can be used to characterize the coating. In other words, EDS / SEM and XRD can be utilized to determine whether the lithiation supplement material powder and the ACC powder are conformally coated on the core powder.

[0107] In some embodiments, an inert gas can be dispersedly filled in a sealed container of a roll mill. Wherein, ball milling mixing can improve the mixing uniformity of the lithiation supplement material powder, the ACC powder, the conductive carbon, and / or the core powder.

[0108] In other embodiments, a wet mixing process can be utilized. As with the dry mixing process, the complementary sizes of the primary core powder particles, the lithium supplement material powder particles, and / or the ACC powder particles can dictate the effectiveness and extent of the coating. In some embodiments, the solvent can be substantially water-free, such that the lithium supplement material powder and the ACC powder can be substantially un-decomposed. The water-free solvent can further prevent the formation of powder agglomerates. The non-polar solvent can affect the polarity of the mixture, such that the core powder particles, the lithium supplement material powder particles, and / or the ACC powder particles in the mixture are attracted to one another through Van der Waals molecular forces. After milling, the solvent can be evaporated through heating or vacuum / gas purging.

[0109] In other embodiments, a high-energy mixing process can be utilized, in which the dry or wet mixing process can be performed in a higher-energy attrition process. Higher-energy collisions can occur in the high-energy mixing process, such that a more complete and uniform coating can be achieved. However, the collisions can be tuned such that the energy of the collisions is not so high as to further reduce the particle size of the core powder, the lithium supplement material powder, and / or the ACC powder. In other words, the mixing energy can be set to not include the effect of true milling or particle size reduction, but can still include more high-energy collisions than previous processing methods.

[0110] In further embodiments, a mechanical fusion mixing process can be utilized. For example, a rotor / stator interaction driven by centrifugal forces can drive high-energy interactions between each of the core powder particles, the lithium supplement material powder particles, and / or the ACC powder particles. Via the strong mechanical energy, each of the core powder particles, the lithium supplement material powder particles, and / or the ACC powder particles can mechanically and / or chemically bond to one another. The mechanical fusion mixing process can be used since the process does not require the use of a solvent or a milling medium. Furthermore, the container can be air-free during the mixing / processing.

[0111] With each of the coating methods as described above, any cathode slurry mixing steps in which the lithium supplement material powder is separately added to the cathode slurry can be omitted, since the step can be completely replaced by the addition of the core powder particles pre-coated with the lithium supplement material. Furthermore, each of the coating methods as described above can ensure a uniform distribution of the lithium supplement material powder particles and / or the ACC powder particles, such that the ACC powder particles can effectively and efficiently catalyze the decomposition process of the lithium supplement material powder particles through maximum inter-particle contact (e.g., through maximum surface area). As a result, agglomeration and under-utilization of the lithium supplement material powder particles can be avoided, such that the lithium supplement material powder particles can decompose to provide an effective source of lithium ions for anode pre-lithiation, for example, in a battery cell.

[0112] Optionally, in some embodiments, a conductive carbon additive and / or a binder can be added. The conductive carbon additive can include, for example, one or more of vapor grown carbon fibers, Super P® TM , carbon black, Super C65, carbon nanotubes, graphene, and porous carbon structures. The binder can include, for example, one or more of PVDF, PVP, PEO, and PI. The conductive carbon additive and / or the binder can be mixed with the core powder coated with the lithium supplement material powder and the ACC powder. As such, any of the mixing processes described above at 606 can be employed to coat the conductive carbon additive and / or the binder onto the core powder. In some embodiments, the conductive carbon additive and / or the binder can be added at 606 with the lithium supplement material powder and the ACC powder. The conductive carbon additive and / or the binder can increase the electrical conductivity of the core powder and improve the kinetics of the core powder.

[0113] At 608, a passivation layer can be applied. The passivation layer can include a polymer, carbon, ceramic, zeolite, or a hybrid coating. The passivation layer can have a thickness of up to 1 pm. In some embodiments, the passivation layer can be optional, such that in some embodiments, no or substantially no passivation layer can be applied.

[0114] In some embodiments, the passivation layer can be a polymer coating. In some embodiments, the polymer coating can be low molecular weight, for example, less than 100,000 Da, and can be applied at low concentration. In additional or alternative embodiments, the polymer coating can include an ionically conductive polymer, for example, cross-linked polyethylene glycol, cross-linked polyvinyl alcohol, polyimide, sodium carboxymethylcellulose, sodium polyacrylate, or combinations thereof. In some embodiments, the coated core material can be mixed in a dilute polymer solution, vacuum filtered, and heat dried to produce the polymer coating. Such a coating can further improve the FCE of a battery cell containing the coated cathode active material. However, such a coating can also decrease the electrical conductivity of the coated cathode active material. Thus, to improve the performance of the battery cell, in additional or alternative embodiments, a highly structured and / or conductive carbon can be further included to produce a composite or hybrid coating. The conductive carbon can include, for example, one or more of vapor grown carbon fibers, Super P® TM , carbon black, Super C65, carbon nanotubes, graphene, and porous carbon structures. In one embodiment, to ensure a percolation network, a conductive carbon that is easily dispersed can be selected, for example, Super P® TM .

[0115] In other embodiments, the passivation layer can be a carbon coating, where the carbon coating can be a pitch or polymer coating, followed by a carbonization step. The carbon coating can be amorphous in form. Further, the carbon coating can incorporate a metal acetylide, where the metal can include one or more of Cu, Al, Mg, Mn, Ni, and Co, and can be selected based on optimal electrical conductivity and thermal stability. The metal can be further selected to be compatible with the voltage extremes of the battery cell of interest. A low temperature process can be utilized for the carbon coating, as at least some lithium supplementing materials, such as lithium peroxide, can decompose at higher temperatures, thereby altering the properties of the coated positive active material. Thus, the low temperature process can be performed at a temperature of less than 280 °C. One example includes the use of copper acetylide as a precursor for the carbon / metal coating, where temperatures as low as 150 °C can precipitate out the metal species. However, if this approach is not performed on a nanoscale, there can be handling hazards, as the resulting mixture can be explosive. Other metal acetylide, such as at least some of the metal acetylide provided above, can reduce the explosiveness and increase handling safety. However, such carbon coatings can be conformal, non-reactive, lithium ion permeable, and can improve the FCE and electrical conductivity of the battery cell.

[0116] In some embodiments, the passivation layer can be generated by any number of methods, including but not limited to glass or ceramic coating techniques.

[0117] In further embodiments, the passivation layer can include a zeolite material. The zeolite coating including the zeolite material can have a highly stable cage-like structure and a controllable pore size, such that the zeolite material does not hinder electron and ion transfer, and can be adjusted accordingly to prevent moisture transfer. Further, the zeolite coating can catalyze electrochemical reactions within the battery cell.

[0118] In other embodiments, the passivation layer can include graphene nanoplatelets, which can be wrapped around the host particles (e.g., coated core particles) by a high-energy mechanical mixing method. The multi-layer graphene structure or wrapped graphene layer can exhibit hydrophobicity and prevent moisture from passing through the passivation layer during handling and manufacturing, while allowing oxygen to be released during battery formation. The wrapped graphene layer can also improve the electronic conductivity of the final powder produced.

[0119] The retrieved coated positive active material can be included in a cathode of a battery cell, the battery cell including at least the cathode, an anode, and an electrolyte. The coated positive active material can effectively and efficiently pre-lithiate the anode, which can improve the FCE and cycle performance of the battery cell. The method 600 then ends.

[0120] Reference is now made to Figure 1FIG. 7 shows a method 700 for manufacturing a coated cathode active material, including applying a surface coating including at least a lithium supplementing material to a core material. A passivation layer can then be applied. In some embodiments, the coated cathode active material can be as discussed above with reference to Figure 2 FIG. 8 shows a coated cathode active material particle 800 as discussed above with reference to Figures 3-5 FIG. 9 shows a coated cathode active material particle 900 as discussed above with reference to Figure 6 FIG. 10 shows a first coated cathode active material 1001, 1101, or 1201 as discussed above with reference to

[0121] At 702, one or more coating materials can be dissolved to obtain a solution. The one or more coating materials can include a lithium supplementing material. For example, the one or more coating materials can also be dispersed in a solvent to obtain a mixture. The lithium supplementing material used in the mixture can be, for example, an anti-fluorite structure material, such as LAO or LFO. In additional or alternative embodiments, the one or more coating materials can further include a CC. The CC can be, for example, a lithium-based ACC (such as NMC or LMFP), or an inert CC (such as cobalt tetraoxide). In some embodiments, the one or more coating materials can include a material that is not a lithium supplementing material or a CC, but the material can be chemically converted into a lithium supplementing material and / or a CC after one or more post-processing processes. In some embodiments, the one or more coating materials can be dissolved in a solvent. The solvent can be any non-aqueous solvent capable of dissolving the one or more coating materials. In some embodiments, the solvent can be an organic solvent, such as acetone, isopropyl alcohol, or NMP. In embodiments where the lithium supplementing material is an anti-fluorite structure material, an aqueous-based solution can not be used because the anti-fluorite structure material can be sensitive to moisture. In additional or alternative embodiments, the lithium supplementing material can be substantially insoluble or can be partially soluble. In such cases, the mixture or solution can include at least particles of the lithium supplementing material fully dispersed and suspended in the solvent. In additional or alternative embodiments, the one or more coating materials can be dissolved in a binder solution. The binder solution can include a binder, such as PVDF, a cellulose derivative, or a linear, semi-aromatic, or aromatic polyimide, dissolved in an organic solvent, such as NMP.

[0122] At 704, the core material can be mixed into the solution containing the one or more coating materials. The core material can be one or more of NMC and NCA, where the NMC can be one or more of NMC111, NMC523, NMC622, and NMC811. The NMC can be a single-phase crystal, or the NMC can be in a polycrystalline or amorphous form. The core material can be in a particulate form having an average particle size of 1 to 20 pm or 6 to 12 pm. The core material can be slowly poured into the solution so as to obtain a stoichiometric ratio between the core material and the one or more coating materials.

[0123] At 706, the solvent can be evaporated. In some embodiments, the solvent can be evaporated by a stirring process. The stirring process can reach at least a temperature required to substantially evaporate the solvent, and the temperature is less than the boiling point of the solvent. In some embodiments, the stirring process can have a duration of 0.5 to 24 hours. In some embodiments, the evaporation can be performed with a vacuum, and the temperature can be lower than in the corresponding stirring process at ambient pressure. In other words, the solution can be continuously stirred at moderate temperatures to evaporate the solvent.

[0124] At 708, the resulting product material can be heated, thereby coating the core material with one or more coating materials. In some embodiments, depending on the solvent selected, the resulting product material can be fired at a firing temperature of 300 to 1200 °C. In other embodiments, depending on the binder and solvent selected, the resulting product material can be annealed at an annealing temperature of 80 to 1200 °C. In some embodiments, the annealing can result in the formation of a polymeric binder. Further, in some embodiments, additional annealing can provide a higher quality polymeric binder.

[0125] At 710, a passivation layer can be applied. The passivation layer can include a polymer, carbon, ceramic, zeolite, or hybrid coating. The passivation layer can have a thickness of up to 1 pm. The passivation layer can be applied in any of the processes described above with reference to Figure 8 In some embodiments, the passivation layer can be optional, such that in some embodiments, no or substantially no passivation layer can be applied.

[0126] The coated cathode active material can be included in a cathode of a battery cell, the battery cell comprising at least the cathode, an anode, and an electrolyte. The coated cathode active material can effectively and efficiently pre-lithiate the anode, thereby improving the FDC and cycling performance of the battery cell. The method 700 then ends.

[0127] Referring now to Figure 1 , a method 800 for manufacturing a coated cathode active material is shown, including converting a surface layer of a core material to obtain a lithiation complementing material and / or CC. A passivation layer can then be applied. In some embodiments, the coated cathode active material can be a coated cathode active material particle 100 as discussed above with reference to Figures 3-5 , a first coated cathode active material 301, 401, or 501 as discussed above with reference to Figure 6 .

[0128] At 802, a core material can be obtained. The core material can be, for example, one or more of NMC and NCA, where NMC can be one or more of NMC 111, NMC 523, NMC 622, and NMC 811. The NMC can be a single phase crystal, or the NMC can be a polycrystalline or amorphous form. The core material can be in a particulate form having an average particle size of 1 to 20 pm or 6 to 12 pm. As discussed in more detail below, the core material can have a surface layer having impurities resulting from synthesis of the core material.

[0129] At 804, one or more precursor materials can be obtained. The one or more precursor materials can be any material that can be converted to a desired lithiation- compensating material and / or CC. The desired lithiation-compensating material can be, for example, one or more of lithium peroxide, lithium oxide, and LAO. The desired CC can be, for example, a lithium-based ACC (such as NMC or LMFP), or an inert CC (such as cobalt tetroxide). In some embodiments, the one or more precursor materials can be milled to achieve a particular size range.

[0130] At 806, the core material can be coated with the one or more precursor materials. Therein, the one or more precursor materials can form a surface layer of the core material. In other embodiments, the core material can include a surface layer having impurities, which in such embodiments can be considered a surface coating. The impurities serve as the precursor material.

[0131] At 808, the surface layer can be converted to obtain a lithiation-compensating material and / or CC. In some embodiments, converting the surface layer can include heating the surface layer to effect a chemical change to produce the lithiation-compensating material and / or CC. In other embodiments, converting the surface layer can involve a chemical process, such as a reaction between the one or more precursor materials and the core material, to produce the lithiation-compensating material and / or CC. As another embodiment, converting the surface layer can involve decomposition and reaction of the one or more precursor materials to produce the lithiation-compensating material and / or CC.

[0132] In one embodiment, converting the surface layer can be performed in a furnace filled with air or an inert gas. Therein, the core material having the surface layer can be heated at a heating temperature of 80 to 1200 °C for a duration of 0.5 to 18 hours. In some embodiments, the heating temperature can be between 200 to 900 °C. In other embodiments, the heating temperature can be between 400 to 800 °C. In some embodiments, the duration can be between 2 to 12 hours. In some embodiments, the duration can be between 2 to 8 hours.

[0133] At 810, a passivation layer can be applied. The passivation layer can include a polymer, carbon, ceramic, zeolite, or a hybrid coating. The passivation layer can have a thickness of up to 1 pm. The passivation layer can be applied as discussed above with reference toFigures 6-8 The passivation layer can be applied in any of the processes described. In some embodiments, the passivation layer can be optional, such that in some embodiments, the passivation layer can not be applied or substantially not applied.

[0134] The coated positive active material collected can be included in a cathode of a battery cell, the battery cell including at least the cathode, an anode, and an electrolyte. The coated positive active material can effectively and efficiently prelithiate the anode, such that the FCE and cycle performance of the battery cell can be improved. The method 800 then ends.

[0135] In exemplary uses, the coated positive active material can be prepared according to a method or combination of methods described above with reference to Figures 9-12 In some embodiments, the coated positive active material can be combined with a conductive additive and a binder to manufacture a cathode or an anode. Further, a battery can be manufactured such that the battery includes a cathode, an anode, or a positive electrode as described above, a separator disposed between the cathode and the anode, and an electrolyte. In some embodiments, the anode can include at least lithium metal. In additional or alternative embodiments, the anode can include silicon or a silicon-graphite composite. In some embodiments, the battery can be a secondary lithium-ion battery. In additional or alternative embodiments, the battery can be one of a plurality of batteries in a battery pack, wherein each of the plurality of batteries can be substantially identical to the battery.

[0136] As an example, Figures 9-12 Characteristics of a lithium-ion battery are shown, the lithium-ion battery including at least a cathode, an anode, a separator disposed between the cathode and the anode, and an electrolyte. For each case discussed with reference to Figure 9 The lithium-ion battery used for each case discussed is a coin cell battery that includes a prelithiated test electrode prepared using a slurry coating method.

[0137] The materials for slurry processing are first prepared, the materials including a lithiu m supplement material, an ACC, a conductive additive, a binder, or a combination thereof. The materials are dispersed in a solvent to obtain a slurry through a high-energy mixing process. The slurry is then coated onto an aluminum foil under ambient conditions or in an inert atmosphere glovebox. The given cathode is finally punched and included in a coin cell battery, wherein the coin cell battery further includes at least an anode that includes at least lithium metal. It should be understood that the method of manufacturing a lithium-ion battery consistent with the inventive concepts disclosed herein can not be limited to the slurry coating method as described above, and the slurry coating method and the resulting lithium-ion battery are included as examples, not limitations.

[0138] Reference is now made to Figure 10FIG. 900 illustrates the potential of a button cell operated at two charging rates (as shown by curves 901 and 902). In an embodiment, the button cell includes at least a lithium metal anode and a cathode. The cathode includes at least a lithiated material, where the lithiated material is lithium peroxide. In each example shown by FIG. 900, the button cell does not include ACC. The charging rates as used herein are selected according to the maximum theoretical specific capacity of lithium peroxide (1168 mAh / g).

[0139] Curve 901 illustrates the potential resulting from applying a constant current to the button cell at a faster first charging rate of C / 40. In the example shown by curve 901, a first specific capacity of 45 mAh / g is observed for the lithium peroxide. Curve 902 illustrates the potential resulting from applying a constant current to the button cell at a slower second charging rate of C / 400. In the example shown by curve 902, a second specific capacity of 150 mAh / g is observed for the lithium peroxide at 40 hours.

[0140] In an embodiment, the lithium peroxide can decompose when a slow charging rate (e.g., C / 400) is applied to the button cell. Specifically, utilizing a slower second charging rate can result in a decrease in overpotential caused by decomposition of the lithium peroxide (as shown by curve 902). In other words, the slower second charging rate can result in a decrease in overpotential of the cathode, which can enable decomposition of the lithium peroxide. To further overcome overpotential in scaled-up applications (e.g., commercial lithium-ion batteries), a nanoscale lithium peroxide particle size can be employed in conjunction with uniform dispersion of the particles on the cathode.

[0141] Referring now to Figure 11 FIG. 1000 illustrates the potential of a button cell including at least a lithium metal anode and a cathode. In an embodiment, the cathode includes at least a lithiated material, where the lithiated material is lithium peroxide. In each tested button cell, a different ratio of ACC to lithiated material is employed. In one embodiment (as shown by curve 1001), no ACC is included in the button cell. In each example shown by FIG. 1000, the ACC is LMFP. Further, in each example, a constant current is applied to the button cell at a charging rate of C / 40, where the charging rate is selected according to the maximum theoretical specific capacity of lithium peroxide (1168 mAh / g).

[0142] Curve 1001 shows the potential of a first coin cell in which there is no LMFP. In the first coin cell, a first specific capacity of 45 mAh / g for lithium peroxide is observed. Curve 1002 shows the potential of a second coin cell in which the cathode includes at least LMFP and lithium peroxide. In the second coin cell, the ratio of LMFP to lithium peroxide is 1 :5, and a second specific capacity of 325 mAh / g for lithium peroxide is observed. Curve 1003 shows the potential of a third coin cell in which the cathode includes at least LMFP and lithium peroxide. In the third coin cell, the ratio of LMFP to lithium peroxide is 1 : 1, and a third specific capacity of 815 mAh / g for lithium peroxide is observed.

[0143] As shown by curves 1001, 1002, and 1003, an increase in the relative amount of the mass of LMFP present in the slurry / cathode formulation can result in an increase in the decomposition of lithium peroxide. The decrease in overpotential from curve 1001 to curve 1002 to curve 1003 demonstrates an increase in decomposition (e.g., as the relative amount of the mass of LMFP increases). An increase in the ratio of LMFP to lithium peroxide increases the total available surface area, thereby facilitating the catalytic decomposition of lithium peroxide. Thus, as more LMFP is provided as ACC, the amount of extractable lithium ions for anode prelithiation can increase. Furthermore, the decrease in overpotential with the addition of LMFP indicates that decomposition of lithium peroxide can be achieved at lower operating potentials in scaled-up applications (e.g., in commercial lithium-ion batteries).

[0144] Reference is now made to PSD FIG. 1100 shows PSD 1101 and PSD 1102 of a milled slurry including at least particles of a lithiation supplement material, where the particles of the lithiation supplement material are lithium peroxide. In some embodiments, the cathode slurry can be free of ACC.

[0145] An exemplary manufacturing process of the slurry can include a premix milling step to reduce the particle size of lithium peroxide and increase the particle dispersion of lithium peroxide. PSD 1101 shows the particle size of lithium peroxide prior to the premix milling step. As shown, PSD 1101 can be characterized by a bimodal distribution with peaks at approximately 10 pm and 100 pm, respectively. After the premix milling step, the particle size of lithium peroxide can be significantly reduced, and the bimodal distribution can shift towards smaller particle sizes. PSD 1102 is illustrative of the particle size of lithium peroxide after the premix milling step. As shown, PSD 1102 can also be characterized by a bimodal distribution with peaks at approximately 0.1 pm and 5 pm, respectively. The D values for PSD 1101 and PSD 1102 are given in Table 1 below.

[0146] Table 1: D values for PSD 1101 and PSD 1102

[0147] D10 (pm) D50 (pm) D90 (pm) PSD 1101 PSD 1102 7.22 35.0 119 Figure 12 0.0596 0.278 3.88

[0148] Prior to the pre-mixing milling step, the measured D50 value was 35.0 pm, while after the pre-mixing milling step, the measured D50 value was 0.278 pm. As such, the pre-mixing milling step can produce sub-micron particle sizes to ensure that the lithium peroxide particles can effectively decompose. In other embodiments, a particle size of about 2 pm or less can ensure that the lithium peroxide particles effectively decompose. Indeed, a particle size range greater than about 2 pm is unlikely to achieve the decomposition.

[0149] In other embodiments, lithium peroxide particles can be employed with a small particle size range and sufficiently uniform dispersion (e.g., non-bimodal distribution) to achieve complete or substantially complete decomposition of the lithium peroxide. As such, the pre-mixing milling step can be controlled such that lithium peroxide particles of a desired particle size and uniform dispersion can be obtained.

[0150] Referring now to Figure 13A FIG. 1200 shows XRD patterns 1201 and 1202 of a first cathode and a second cathode, respectively. In one embodiment, each of the first cathode and the second cathode can include at least a positive active material coated with a lithium supplementing material and a CC, where the positive active material is NMC, the lithium supplementing material is lithium peroxide, and the CC is cobalt tetroxide. XRD pattern 1201 shows the first cathode, where the first cathode is in an as- received condition. XRD pattern 1202 shows the second cathode after cycling. Peaks 1203 can be attributed to lithium peroxide. Comparing XRD patterns 1201 and 1202 indicates that the peaks of lithium peroxide are significantly reduced after cycling.

[0151] Referring now to Figure 13B SEM image 1300 shows coated positive active material particles 1301, where the coating of the coated positive active material includes a lithium supplementing material, an ACC, and a conductive carbon additive. In one embodiment, the positive active material of the coated positive active material particles 1301 is NMC, the lithium supplementing material is lithium peroxide, and the ACC is LMFP. The coated positive active material particles 1301 can have a particle diameter of about 15 pm. As shown, the coating completely covers the surface of the positive active material particle that supports the coating. Further shown are different topographical features of the coating, indicating a degree of roughness that can be caused by the non-uniform particle size and shape of the various coating materials.

[0152] Referring now to Figure 13A EDS map of Fe overlaid on SEM image 1320 of coated positive active material particles 1321, the composition of which can be as described above with reference to Figure 13CThe coated cathode active material particles 1301 are the same. Specifically, the coating can include LMFP as the ACC. As shown, the LMFP is uniformly distributed among the coated cathode active material particles, which indicates that the coating process achieves uniform dispersion of the LMFP. EDS mapping of Fe (brighter areas on the surface of the coated cathode active material particle 1321) can confirm the presence of LMFP within the coating. Furthermore, no LMFP-only agglomerates are observed, indicating that the LMFP is substantially fully utilized as the coated ACC.

[0153] Referring now to Figure 13A , FIG. 1340 shows XRD patterns 1341 of coated cathode active material particles, such as the coated cathode active material particles 1301 and 1321 described above with reference to Figure 13C and 13B respectively. Specifically, the coating of the coated cathode active material particles can include lithium peroxide as the lithiation supplement material and LMFP as the ACC. The XRD patterns 1341 are characterized by peaks 1342 and 1343, which indicate the presence of lithium peroxide and LMFP, respectively. From this, XRD (e.g., the XRD patterns 1341 of Figure 13A ), SEM images, and EDS mapping thereon (e.g., the SEM images 1300 and 1320 of Figure 14 and 13B respectively) can be employed to structurally characterize the coated cathode active material particles and confirm the composition of the coating disposed thereon.

[0154] Referring now to Figure 15 , a plot 1400 of FCC voltage of half-cells is shown, where the half-cells can be defined by anodes including lithium metal, and first and second cathodes including no lithiation supplement material and having lithiation supplement material coated on the cathode active material particles included therein, respectively. In an embodiment, the lithiation supplement material is lithium peroxide. Furthermore, the specific capacity can be determined based on the core composition of the cathode active material particles.

[0155] Curves 1401 and 1402 show initial charging of the first and second cathodes, respectively, and comparing the curves 1401 and 1402 elucidates a plateau 1405 in the curve 1402, which can be attributed to decomposition of the lithium peroxide at higher potentials (e.g., greater than about 4.3 V). Notably, the curve 1402 corresponds to a higher first charge capacity (FCC) (e.g., greater than 250 mAh / g) compared to the curve 1401, which can be attributed to the prelithiation effect of the lithiation supplement material. Furthermore, curves 1403 and 1404 depict initial discharging of the first and second cathodes, respectively, showing substantially similar discharging trends.

[0156] Referring now toFigure 16 FIG. 1500 illustrates FCC voltage profiles 1500 for full cells, which can be defined by anodes comprising materials other than lithium metal (e.g., carbon or silicon), and cathodes comprising a first cathode free of a lithiation supplementing material and a second cathode having a lithiation supplementing material coated on cathode active material particles included therein, respectively. In one embodiment, the lithiation supplementing material is lithium peroxide. Further, specific capacities can be determined based on the core composition of the cathode active material particles.

[0157] Curves 1501 and 1502 illustrate initial charging of the first and second cathodes, respectively. Comparing curves 1501 and 1502 elucidates plateau 1505 in curve 1502, which can be attributed to decomposition of lithium peroxide at higher potentials (e.g., greater than about 4.3 V). Further, curves 1503 and 1504 illustrate initial discharging of the first and second cathodes, respectively. Notably, curve 1502 corresponds to a higher FCC charge capacity (e.g., greater than 250 mAh / g) than curve 1501, which can be attributed to the prelithiation effect of the lithiation supplementing material. Additionally, curve 1504 corresponds to a higher FDC discharge capacity (e.g., about 200 mAh / g) than curve 1503, which can also be attributed to the prelithiation effect of the lithiation supplementing material.

[0158] Referring now to Figure 17A FIG. 1600 illustrates discharge capacities during initial four charge cycles for two full cells comprising a first cathode free of a lithiation supplementing material and a second cathode having a lithiation supplementing material coated on cathode active material particles included therein, respectively. In one embodiment, the lithiation supplementing material is lithium peroxide. Further, discharge capacities can be determined based on the core composition of the cathode active material particles.

[0159] Specifically, bars 1601, 1611, 1621, and 1631 represent discharge capacities for the first, second, third, and fourth cycles, respectively, of a full cell comprising the first cathode. Further, bars 1602, 1612, 1622, and 1632 represent discharge capacities for the first, second, third, and fourth cycles, respectively, of a full cell comprising the second cathode. As shown, for each tested charge cycle, the full cell comprising the second cathode has a higher discharge capacity than the full cell comprising the first cathode, which can be attributed to the prelithiation effect of the lithiation supplementing material included in the second cathode.

[0160] Referring now to Figure 17B Schematic 1700 illustrates exemplary steps of a method of impregnating (porous) carbon source particles 1722 with lithiation supplementing material particles 1744. As described below with reference to FIG. 1800, the method of FIG. 1700 can be used to produce a cathode active material particle 1742 having a lithiation supplementing material 1744 coated on a core 1722 included therein. Figures 6-8As discussed in detail, the impregnated carbon source particles 1742 can be subsequently coated onto the positive active material particles. It will be appreciated that the impregnated carbon source particles 1742 formed by the illustrated process can be combined with the reference Figures 1-5 coating methods described above with reference to Figure 17A the lithium supplement material particles.

[0161] Starting with the first example schematic 1710, a container can be obtained that includes lithium supplement material precursor particles 1714 dispersed in a solvent 1712. In some embodiments, the solvent 1712 can be methanol, and the lithium supplement material precursor particles 1714 can be lithium hydroxide monohydrate (LiOH-H20). In some embodiments, the lithium supplement material precursor particles 1714 can be dissolved in the solvent 1712 at a concentration of 0.1 M.

[0162] As indicated by directional arrow 1715, carbon source particles 1722 can then be added, with the second example schematic 1720 illustrating the resulting solution. When the carbon source particles 1722 are added, the solution containing the lithium supplement material precursor particles 1714 dispersed in the solvent 1712 can be vigorously stirred. As illustrated, the carbon source particles 1722 can be porous carbon having pores or voids 1724 throughout. In some embodiments, the carbon source particles 1722 can include Lion carbon particles (e.g., Lion 403 or Lion 509). The carbon source particles 1722 can be selected to have a d50 particle size of about 1 pm, or larger particles can be ground to a d50 particle size of about 1 pm. Alternatively, pre-existing carbon source particles 1722 can be ground to a d50 particle size of less than 1 pm. In some embodiments, a bimodal PSD can be obtained, with each peak of the bimodal PSD being at or less than 1 pm. Such a bimodal PSD can allow for more efficient coating onto a surface coating, or formation of a surface coating. In some embodiments, about 100 mg of carbon source particles 1722 can be added per 100 mL of solution.

[0163] As indicated by directional arrow 1725, the resulting solution can then be sonicated for a first predetermined duration, such as 15 minutes, and / or the resulting solution can be soaked for a second, longer predetermined duration. In this way, the lithium supplement material precursor particles 1714 dispersed in the solvent 1712 can more completely distribute between the carbon source particles 1722, and can penetrate the pores 1724 thereof to form precursor-impregnated carbon source particles 1732, as illustrated by the third example schematic 1730.

[0164] As indicated by directional arrow 1735, a lithium supplement material forming solution can be subsequently added to form lithium supplement material particles 1744. In embodiments where lithium supplement material precursor particles 1714 comprise lithium hydroxide monoxide, the lithium supplement material forming solution can comprise a 15 mol% excess of 50% hydrogen peroxide (H2O2) solution. In such embodiments, the lithium supplement material forming solution can be added dropwise to solvent 1712 with precursor-impregnated carbon source particles 1732. The resulting solution can then be stirred vigorously at 35 °C. Lithium supplement material particles 1744 can then form within voids 1724 of carbon source particles 1722, resulting in impregnated carbon source particles 1742, as shown in fourth exemplary schematic 1740. In some embodiments, lithium supplement material particles 1744 thus formed can consist of lithium peroxide complexes. For example, lithium supplement material particles 1744 can consist of Li2O2·H2O2·3H2O·8CH3OH.

[0165] As indicated by directional arrow 1745, the resulting solution (i.e., impregnated carbon source particles 1742 dispersed in solvent 1712) can be filtered or centrifuged on filter paper and decanted to obtain impregnated carbon source particles 1742, as shown in fifth exemplary schematic 1750. Impregnated carbon source particles 1742 can then be repeatedly rinsed (e.g., with methanol and ethanol). In some embodiments, after rinsing, impregnated carbon source particles 1742 can be centrifuged, decanted, and rinsed again. Impregnated carbon source particles 1742 can then be collected and vacuum dried at a temperature between about 100 °C and 110 °C for 24 hours.

[0166] As indicated by directional arrow 1745, the resulting solution (i.e., impregnated carbon source particles 1742 dispersed in solvent 1712) can be filtered or centrifuged on filter paper and decanted to obtain impregnated carbon source particles 1742, as shown in fifth exemplary schematic 1750. Impregnated carbon source particles 1742 can then be repeatedly rinsed (e.g., with methanol and ethanol). In some embodiments, after rinsing, impregnated carbon source particles 1742 can be centrifuged, decanted, and rinsed again. Impregnated carbon source particles 1742 can then be collected and vacuum dried at a temperature between about 100 °C and 110 °C for 24 hours. Figure 17B The impregnation process as shown in Figure 6 may ensure uniform distribution of lithium supplement material particles 1744 as well as a small particle size. In some embodiments, about 30% of the volume of carbon source particles 1722 can be occupied by lithium supplement material particles 1744. That is, carbon source particles 1722 can have a porosity of about 30%. As such, when impregnated carbon source particles 1742 are coated onto positive active material particles, as described below with reference to Figures 6-8The method 600 is described. In this dry coating process, other catalysts (e.g., CC or ACC) and binders can be used in conjunction with the impregnated carbon source particles 1742 to form a continuous and uniform coating on the positive active material particles.

[0167] Referring now to Figures 1-5 , a schematic 1760 illustrates exemplary steps of a process to coat positive active material particles 1772 with the impregnated carbon source particles 1742 to form first coated positive active material particles 1782. A plurality of the first coated positive active material particles 1782 can then be coated onto a cathode current collector to form a cathode in a lithium ion battery, whereby the impregnated carbon source particles 1742 can act as both a conductive additive and a pre-lithiation source during cycling. It should be appreciated that the first coated positive active material particles 1782 can be formed in conjunction with one or more coating methods described above with reference to Figure 18 It should also be appreciated that the positive active material particles 1772 can be any positive active material particles described above with reference to Figure 17A .

[0168] Starting from the sixth exemplary schematic 1770, the positive active material particles 1772 can be obtained. In some embodiments, the positive active material particles 1772 can consist of NMC. It should be appreciated that the positive active material particles 1772 can be obtained at a predetermined particle size, or can be milled from an initially larger particle size to a desired particle size. As indicated by directional arrow 1775, the positive active material particles 1772 can be coated with the impregnated carbon source particles 1742, for example, by a mechanical fusing dry mixing method. As shown in the seventh exemplary schematic 1780, the first coated positive active material particles 1782 can thus be formed.

[0169] As indicated by directional arrow 1785, the first coated positive active material particles 1782 can then be coated onto a cathode current collector (e.g., a slurry-based method) along with other first coated positive active material particles 1782 formed similarly and used in a lithium ion battery. During initial battery cycling, the lithium supplement material particles 1744 in the impregnated carbon source particles 1742 can subsequently decompose into first and second decomposition products 1794 and 1796. In this way, second coated positive active material particles 1792 that are partially free or substantially free of the lithium supplement material particles 1744 can be formed, as shown in the eighth exemplary schematic 1790.

[0170] In embodiments where the lithium replenishment material particles 1744 include lithium peroxide, the first decomposition product 1794 can be lithium ions, and the second decomposition product 1796 can be oxygen. Specifically, the first and second decomposition products 1794 and 1796 can exit the voids (e.g., 1724) of the carbon source particles 1722 and enter the electrolyte contained in the lithium-ion battery. Because the voids of the carbon source particles 1722 may be partially or substantially devoid of lithium replenishment material particles 1744, the carbon source particles 1722 can provide an extended percolation network for the electrolyte and lithium ions within the coating of the second-coated positive electrode active material particles 1792 by retaining a portion of the electrolyte in their voids after the decomposition of the lithium replenishment material particles 1744. In turn, this extended percolation network can improve conductivity by providing additional electronic pathways.

[0171] Furthermore, the carbon source particles 1722 can provide additional structural integrity to the coating of the second-coated positive electrode active material particles 1792, thereby helping to ensure that the coating remains intact and stable. The stable coating retaining the carbon source particles 1722, and the resulting conductivity benefits, can lead to further improvements in electrochemical performance. In some embodiments, it may therefore be unnecessary to add other conductive additives to the coating. In another or alternative embodiment, if the carbon source particles 1722 maintain good electrical contact with the high-surface-area lithium supplementation material particles 1742 prior to decomposition, the coating may be free of other catalysts (e.g., CC or ACC).

[0172] Now for reference Figure 17B The diagram illustrates a method 1800 for forming a carbon source impregnated with a lithium-replenishing material. The carbon source impregnated with the lithium-replenishing material can then be coated onto a positive electrode active material. It will be understood that the carbon source can be any of the methods described above. Figure 17A and 17B The carbon source particles mentioned are 1722. It should also be understood that the positive electrode active material can be any of the above-mentioned references. Figure 17A The positive electrode active material particles 1772 are described above.

[0173] In 1802, the lithium supplementation material precursor can be dissolved in a solvent to obtain a first precursor solution (e.g., as shown in Figure 1802). Figure 17A (As shown in the first exemplary schematic diagram 1710). In some embodiments, the lithium supplementation material precursor may be lithium hydroxide monohydrate, and the solvent may be methanol. In such an example, the lithium supplementation material precursor may be dissolved in the solvent at a concentration of 0.1 M.

[0174] In 1804, a carbon source can be added to the first precursor solution (e.g., as shown in Figure 1804). Figure 17A (As shown in the second exemplary schematic diagram 1720). In some embodiments, the carbon source may be a porous carbon source, such as... Lion carbon particles (e.g., Lion 403 or In some embodiments, about 100 mg of the carbon source can be added per about 100 mL of the first precursor solution. The total amount of the carbon source added can depend on one or more of the particle size and the PSD of the carbon source. For example, the d50 particle size of the carbon source can be selected to be 1 pm, or the carbon source can be milled to a d50 particle size of less than 1 pm. As another example, the PSD can be bimodal, with each peak of the bimodal PSD being at or below 1 pm.

[0175] At 1806, the carbon source can be impregnated with the lithium supplement material precursor (e.g., as shown in the third exemplary schematic 1730 of FIG. 17B). In some embodiments, the first precursor solution can be sonicated for about 15 minutes. In additional or alternative embodiments, the first precursor solution can be left for an extended period of time (e.g., more than 15 minutes) to allow the lithium supplement material precursor to penetrate into the pores of the carbon source. Figure 17A At 1808, a second precursor solution can be added to the first precursor solution to form a lithium supplement material impregnated within the carbon source (e.g., as shown in the fourth exemplary schematic 1740 of FIG. 17B). In embodiments where the lithium supplement material precursor is lithium hydroxide monohydrate and the solvent is methanol, the second precursor solution can be 15 mol% excess of 50% hydrogen peroxide. In additional or alternative embodiments, the second precursor solution can be added dropwise with vigorous stirring at 35 °C. In some embodiments, the lithium supplement material thus formed can be lithium peroxide.

[0176] Figure 17B At 1810, the carbon source impregnated with the lithium supplement material can be extracted from the resulting solution (e.g., as shown in the fifth exemplary schematic 1750 of FIG. 17B). In some embodiments, extracting the carbon source impregnated with the lithium supplement material can include filtering the resulting solution on filter paper. In other embodiments, extracting the carbon source impregnated with the lithium supplement material can include centrifuging and decanting the resulting solution. The extracted carbon source impregnated with the lithium supplement material can then be repeatedly washed with methanol and ethanol. In some embodiments, extracting the carbon source impregnated with the lithium supplement material includes centrifuging and decanting the resulting solution, which can be followed by repeated centrifuging, decanting, and washing. The carbon source impregnated with the lithium supplement material can then be collected and vacuum dried at, for example, 100 to 110 °C for 24 hours.

[0177] At 1812, the cathode active material can be coated with the carbon source impregnated with the lithium supplement material (e.g., as shown in the seventh exemplary schematic 1780 of FIG. 17B). In some embodiments, the cathode active material can be NMC. In some embodiments, coating the cathode active material can include a mechanical fusion dry coating process, such as described above with reference to Figure 6

[0178] Figure 6 Figure 8 ​​​​The coated cathode active material can then be coated onto a cathode current collector (e.g., a slurry-based method) to form a cathode for a lithium-ion battery. The cathode for a lithium-ion battery can provide pre-lithiation during initial cycling of the lithium-ion battery. As such, both the FDC and cycling performance of the final lithium-ion battery can be improved.

[0179] To obtain a cathode including uniformly mixed cathode active material, lithium supplement material, and carbon source, a slurry-based method employing a polymeric binder can be utilized. Typical slurry-based methods in the prior art can use PVDF or PVDF-co-hexafluoropropylene copolymer (PVDF-HFP) as a polymeric binder regardless of whether a lithium supplement material is included. However, according to such prior art, the inventors have unexpectedly found that PVDF and PVDF-HFP are strongly incompatible with lithium supplement materials such as lithium peroxide. Specifically, many lithium supplement materials are typically basic when in contact with trace amounts of water, which is typically unavoidable in slurry preparation. In such a basic environment, PVDF and PVDF-HFP can rapidly and irreversibly gel due to dehydrofluorination. As a result, inferior slurry coating materials or unmanageable slurries that cannot be coated at all can be produced. As such, PVP can be used in place of PVDF or PVDF-HFP, thereby completely avoiding dehydrofluorination. As such, using PVP as a polymeric binder to bind coated cathode active material particles in a slurry-based method can achieve higher quality slurries and coatings.

[0180] In some embodiments, the final formed slurry can have a binder content of 0-10 wt%, 1-6 wt%, or 2-5 wt%. In some embodiments, the final formed slurry can have a carbon content of 0-10 wt%, 1-5 wt%, or 2-4 wt%. The weight percentage of the lithium supplement material can depend on the composition of the anode paired with the cathode in the lithium-ion battery. For example, the final formed slurry can have a lithium supplement material content range of less than 15 wt%, 10 wt%, or 5 wt%. In some embodiments, the final formed slurry can have a lithium supplement material content of 1-4 wt%. Furthermore, when CC is included in the final formed slurry, the ratio of CC to lithium supplement material can depend on the composition of the CC. For example, the ratio of CC to lithium supplement material in the final formed slurry can range between 1:1 and 4:1. As another example, the ratio of CC to lithium supplement material in the final formed slurry can range between 0.2:1 and 0.7:1. In some embodiments, the final formed slurry can have a cathode active material content of 80-100 wt% or 85-95 wt%.

[0181] In further embodiments, a method for manufacturing a coated cathode active material can include obtaining a lithiated core material having a surface layer; and converting the surface layer to obtain a lithiu m supplementing material. The core material can be one or more of NMC and NCA, where NMC can be one or more of NMC111, NMC523, NMC622, and NMC811. The NMC can be single phase crystalline, or the NMC can be polycrystalline or amorphous form. In some embodiments, the core material can be in the form of a particle having an average particle size of 1 to 20 pm or 6 to 12 pm.

[0182] In some embodiments, the core material can include one or more impurities, such as Li20, LiOH, or Li2CC>3, which can result from the synthesis process of the core material. In some embodiments, the impurities can be contained within the surface layer of the core material. In some embodiments, converting the surface layer can include converting one or more impurities in the surface layer to the lithium supplementing material. In some embodiments, converting the surface layer can include heating the surface layer such that a chemical change can be achieved, thereby producing the lithium supplementing material. In other embodiments, converting the surface layer can involve a chemical reaction in which one or more impurities can be used as a reactant, thereby producing the lithium supplementing material.

[0183] In some embodiments, a passivation layer can be subsequently applied. The passivation layer can include a polymer, carbon, ceramic, zeolite, or hybrid coating. The passivation layer can have a thickness of at most 1 pm. The passivation layer can be implemented in any of the processes described above with reference to ​ In some embodiments, the passivation layer can be optional, such that in some embodiments no or substantially no passivation layer can be applied. The coated cathode active material collected can be included in a cathode of a battery cell, the battery cell including at least the cathode, an anode, and an electrolyte. The coated cathode active material can effectively and efficiently prelithiate the anode, thereby improving the FCE and cycle performance of the battery cell. In some embodiments, the methods described above can be implemented in whole or in part in conjunction with the methods 800 described with reference to ​

[0184] ​In further embodiments, prelithiation can extend beyond the first charge cycle. As such, a battery cell comprising at least an anode and a cathode can be designed such that the cathode lithiation material can provide lithium ions to the anode over an extended cycle period of the battery cell. In some embodiments, extended anode prelithiation can include various combinations of lithiation materials and / or CCs (e.g., ACC, inert CCs) to achieve tailored voltage performance. The lithium ion release potential of a given lithiation material can depend on the composition of the material, the particle size of the material, and the presence of one or more CCs. During cycling, the battery cell can reach potentials across a range of potentials such that prelithiation can be needed at both the higher and lower ends of the range. As such, one or more catalyst compositions can be used that are compatible with one or more particle sizes.

[0185] In further embodiments, one or more passivation layers can be applied to the surface of the positive active material particles comprising one or more lithiation materials, catalysts, or combinations thereof. The one or more passivation layers can include semi-permeable coatings or stabilized lithiated compounds such as Li2CO3 as described above.

[0186] In some embodiments, the lithiation material in the form of a cathode additive for anode prelithiation can include one or more binary and / or ternary compounds. Binary compounds can include Li2S, Li3N, LiN3, Li2O, Li2O2, LiF, or combinations thereof. The decomposition of Li2S can result in lithium ion release and the formation of sulfur. Li3N can exhibit a higher theoretical capacity compared to other materials described herein. The decomposition of Li3N can result in lithium ion release and the formation of nitrogen gas. In some embodiments, binary compounds can include lithium and oxygen, such as Li2O and Li2O2. The decomposition of Li2O and Li2O2 can result in the release of lithium ions and the formation of oxygen gas, with no remaining solid material in a given cathode. Both Li2O and Li2O2 exhibit high capacity, and thus, less material is needed to effectively prelithiate an anode in a battery cell compared to, for example, anti-fluorite structured materials.

[0187] Ternary compounds can include lithium, oxygen, and a transition metal. In some embodiments, ternary compounds can include Li5AlO4, Li5FeO4, Li2NiO2, Li6CoO4, Li2MoO3, or combinations thereof. Anti-fluorite structured materials such as Li5AlO4 and Li5FeO4 can result in lithium ion release and the formation of metal oxides and oxygen gas. Anti-fluorite structured materials can not bring lithium ions back over the typical battery voltage range, thus irreversibly providing lithium ions to prelithiate an anode in a battery cell.

[0188] The lithium supplementing material can be a mixture of one or more binary compounds (e.g., one or more of Li2S, LiF, and Li2O) and one or more metals (e.g., Co) to form a conversion-type pre-lithiation reagent. In certain charge voltage ranges, the conversion reaction can release lithium ions and form corresponding metal compounds, such as one or more of CoS, CoF3, and Co3O4. Substantial mixing can be required to lower the conversion voltage to a desired value.

[0189] Additional CCs, such as ACCs, can be required to lower the voltage used to decompose the lithium supplementing material to a desired value. In some embodiments, the CCs can include Pt, La 0.8 Sr 0.2 MnO3, Fe2O3, NiO, Fe3O4, Co3O4, CuO, CoFe2O4, LiFe 0.5 Mn 0.5 PO4, or combinations thereof. Additionally or alternatively, a reduction in the particle size of the lithium supplementing material can lower the voltage used to decompose the material to a desired value. At least some example lithium supplementing materials and / or CC compositions can leave behind residues within and / or on the cathode that can reduce the energy density. The manufacture of such lithium supplementing materials and / or catalysts can utilize similar configurations and methods disclosed herein.

[0190] In this way, a coated positive electrode active material for a lithium ion battery is provided. The lithium supplementing material included in the coated positive electrode active material can provide an excess of lithium ions to the battery, which can compensate for undesirable loss of lithium at the anode in the battery. The excess lithium ions provided by the lithium supplementing material can also be used to form a solid electrolyte interphase layer if the lithium supplementing material decomposes at a lower potential than the delithiation potential of the positive electrode active material itself. The lithium supplementing material, when decomposed, can produce one or more decomposition products that are easily removed, such as oxygen, or can leave behind residues that can impart secondary benefits (e.g., safety, cycle stability) to the battery. The coated positive electrode active material can optionally include a passivation layer such that the other components of the coated positive electrode active material can be protected from degradation caused by air, moisture, and electrolyte in the battery. One technical effect of the proposed coated positive electrode active material can be that the first cycle discharge capacity and cycle performance of the battery can be improved.

[0191] In one embodiment, a positive electrode active material for a lithium ion battery includes a lithiated compound core and a surface coating that coats the core, the surface coating including at least a lithium supplementing material. In some embodiments, the surface coating includes a lithium supplementing material to cathode catalyst weight ratio of 10: 1 to 1 : 10.

[0192] In another embodiment, a method for manufacturing a positive active material, the method comprising: milling a lithiu m supplement material powder to a first average particle size, milling a cathode catalyst powder to a second average particle size, and mixing the lithium supplement material powder and the cathode catalyst powder and coating a lithiated core powder.

[0193] In yet another embodiment, a method for manufacturing a positive active material, the method comprising: obtaining a lithiated core material having a surface layer, and converting the surface layer to obtain one or both of a lithium supplement material and a cathode catalyst. In some embodiments, the surface layer comprises one or more impurities. In additional or alternative embodiments, the impurities are one or more of Li2O and Li2CO3, and converting the surface layer comprises converting the impurities to the lithium supplement material. In additional or alternative embodiments, the surface layer comprises one or more precursor materials.

[0194] In yet another embodiment, a lithium ion battery, comprising: a positive electrode comprising a lithiated compound coated by a surface coating, wherein the surface coating comprises a lithium supplement material, a lithium-based active cathode catalyst, or a combination thereof; a negative electrode comprising at least lithium metal; a separator disposed between the positive electrode and the negative electrode; and an electrolyte. In some embodiments, the negative electrode further comprises silicon or a silicon-graphite composite.

[0195] In one embodiment, a cathode material for a lithium-ion battery includes a lithiated compound core and a surface coating coating the lithiated compound core, the surface coating including a lithium supplementing material, wherein the lithium supplementing material is in a particulate form having a particle size distribution with a peak at 1 pm or less than 1 pm. A first embodiment of the cathode material further includes that the lithiated compound core is NMC or NCA. A second embodiment of the cathode material (optionally including the first embodiment of the cathode material) further includes that a passivation layer coats the surface coating. A third embodiment of the cathode active material (optionally including one or more of the first and second embodiments of the cathode active material) further includes that the lithium supplementing material is one or more of lithium peroxide, lithium oxide, lithium nitride, lithium aluminum oxide, and lithium iron oxide. A fourth embodiment of the cathode active material (optionally including one or more of the first through third embodiments of the cathode active material) further includes that the surface coating further includes a cathode catalyst. A fifth embodiment of the cathode active material (optionally including one or more of the first through fourth embodiments of the cathode active material) further includes that the cathode catalyst is a first lithium mixed metal oxide, a lithium phosphate compound, a metal oxide, or a combination thereof. A sixth embodiment of the cathode active material (optionally including one or more of the first through fifth embodiments of the cathode active material) further includes that the cathode catalyst is cobalt tetraoxide. A seventh embodiment of the cathode active material (optionally including one or more of the first through sixth embodiments of the cathode active material) further includes that the cathode catalyst is a first lithium mixed metal oxide and the lithiated compound core is a second lithium mixed metal oxide, wherein the first lithium mixed metal oxide is the second lithium mixed metal oxide. An eighth embodiment of the cathode active material (optionally including one or more of the first through seventh embodiments of the cathode active material) further includes that the cathode catalyst is a first lithium mixed metal oxide and the lithiated compound core is a second lithium mixed metal oxide, wherein the first lithium mixed metal oxide is different from the second lithium mixed metal oxide. A ninth embodiment of the cathode active material (optionally including one or more of the first through eighth embodiments of the cathode active material) further includes that the surface coating includes the lithium supplementing material and the cathode catalyst in a weight ratio of about 1 :0.7 to about 1 :4.

[0196] In another embodiment, a method for manufacturing a cathode material includes: obtaining one or more precursor materials; converting the one or more precursor materials into one or more lithiation-supporting materials and / or a cathode catalyst; and forming a cathode material including a lithiated core material having a surface layer disposed thereon, wherein the surface layer includes the one or more lithiation-supporting materials and / or the cathode catalyst therein. A first embodiment of the method further includes converting the one or more precursor materials includes: reacting the lithiated core material with the one or more precursor materials to produce the one or more lithiation-supporting materials and / or the cathode catalyst, or decomposing and reacting the one or more precursor materials to produce the one or more lithiation-supporting materials and / or the cathode catalyst. A second embodiment of the method (optionally including the first embodiment of the method) further includes, wherein impregnating the porous carbon source with at least one of the one or more precursor materials, and converting the one or more precursor materials into the one or more lithiation-supporting materials such that the one or more lithiation-supporting materials are impregnated in the porous carbon source. A third embodiment of the method (optionally including one or more of the first and second embodiments of the method) further includes, forming the cathode material includes: coating the lithiated core material with the porous carbon source impregnated with the one or more lithiation-supporting materials such that the surface layer includes the porous carbon source impregnated with the one or more lithiation-supporting materials. A fourth embodiment of the method (optionally including one or more of the first through third embodiments of the method) further includes, wherein the lithiated core material is NMC, and the one or more lithiation-supporting materials include lithium peroxide. A fifth embodiment of the method (optionally including one or more of the first through fourth embodiments of the method) further includes, the method further includes applying a passivation layer.

[0197] In yet another embodiment, a lithium-ion battery includes: a positive electrode including a cathode current collector coated with a cathode material layer, wherein the cathode material layer includes a lithiated compound coated with a surface coating, the surface coating including a lithiation-supporting material and a lithium-based active cathode catalyst, a polyvinylpyrrolidone binder; a negative electrode including at least lithium metal; a separator disposed between the positive electrode and the negative electrode; and an electrolyte. A first embodiment of the lithium-ion battery further includes wherein the lithiation-supporting material is lithium peroxide or lithium aluminum oxide. A second embodiment of the lithium-ion battery (optionally including the first embodiment of the lithium-ion battery) further includes, wherein the lithiated compound is further coated with a passivation layer that coats the surface coating.

[0198] In yet another embodiment, a method for manufacturing a positive electrode active material, comprising: milling a lithium supplement material powder to a first average particle size; milling a cathode catalyst powder to a second average particle size; and mixing and coating the lithium supplement material powder and the cathode catalyst powder with a lithiated core powder, wherein the first average particle size and the second average particle size are each 1 pm or less. A first embodiment of the method further comprises the lithium supplement material powder is lithium peroxide. A second embodiment of the method (optionally including the first embodiment of the method) further comprises wherein the lithiated core powder has an average particle size of 1 to 20 pm. A third embodiment of the method (optionally including one or more of the first and second embodiments of the method) further comprises wherein the method further comprises applying a passivation layer.

[0199] The following claims particularly point out certain combinations and subcombinations that are regarded as novel and nonobvious. Such claims can refer to "a" or "a first" element or to "one" element or to an element by reciting "means for" doing something. Such claims should be understood as including one or more such elements irrespective of how those elements are characterized or referred to in the specification. All combinations and subcombinations are intended to come within the scope of the present disclosure. Other combinations and subcombinations can be claimed by amending present claims (presently claimed combinations), by presenting new claims or by presenting amended claims during the prosecution of the claims matrix of the patent application. Such amended claims, whether they are presented during the prosecution of the original application or presented since new applications are filed, will apply to the patent applications in the same way any other amended claims.

Claims

1. A cathode material for lithium-ion batteries, comprising: Lithium compound core particles; and A surface coating that coats and adheres to the lithium compound core particles, the surface coating comprising a lithium-replenishing material. The lithium replenishing material is in the form of particles with a particle size distribution, the peak of which is located at 1 μm or less. The passivation layer covers the surface coating, and the surface coating is located between the lithium compound core particles and the passivation layer.

2. The cathode material according to claim 1, wherein, The lithium compound core particles are NMC or NCA.

3. The cathode material according to any one of claims 1 to 2, wherein, The lithium replenishing material is one or more of lithium peroxide, lithium oxide, lithium nitride, lithium aluminum oxide, and lithium iron oxide, and The surface coating also includes one or more of lithium carbonate and lithium hydroxide.

4. The cathode material according to claim 1, wherein, The surface coating also includes a cathode catalyst.

5. The cathode material according to claim 4, wherein, The cathode catalyst is a lithium mixed metal oxide, lithium phosphate compound, metal oxide, or a combination thereof.

6. The cathode material according to claim 5, wherein, The cathode catalyst is cobalt tetroxide.

7. The cathode material according to claim 4, wherein, The cathode catalyst is a first lithium mixed metal oxide, and The lithium compound core particles are a second lithium mixed metal oxide. The first lithium mixed metal oxide may be the same as or different from the second lithium mixed metal oxide.

8. The cathode material according to any one of claims 4 to 7, wherein, The surface coating comprises the lithium replenishing material and the cathode catalyst in a weight ratio of 4:1 to 1:

4.

9. A method for manufacturing a cathode material, the method comprising: Convert one or more precursor materials into one or more lithium supplementation materials and / or cathode catalysts; and The cathode material is formed by comprising lithium-ion core material particles having a surface layer thereon, wherein one or more lithium supplementation materials and / or the cathode catalyst are contained in the surface layer, the surface layer coating and adhering to the lithium-ion core material particles. The method further includes applying a passivation layer to the cathode material, wherein the passivation layer covers the surface layer and the surface layer is located between the lithium core material particles and the passivation layer.

10. The method according to claim 9, wherein, The conversion of one or more precursor materials includes: The lithium-ion core material particles are reacted with one or more precursor materials to produce one or more lithium-replenishing materials and / or the cathode catalyst; or The one or more precursor materials are decomposed and reacted to produce the one or more lithium supplement materials and / or the cathode catalyst.

11. The method according to claim 9, wherein, The conversion of one or more precursor materials includes: Impregnating a porous carbon source with at least one of the one or more precursor materials; and The one or more precursor materials are converted to form the one or more lithium-supplementing materials, such that the one or more lithium-supplementing materials are impregnated in the porous carbon source, and Forming the cathode material includes coating the lithium core material particles with the porous carbon source impregnated with the one or more lithium replenishing materials, such that the surface layer includes the porous carbon source impregnated with the one or more lithium replenishing materials.

12. The method according to any one of claims 9 to 11, wherein, The lithium-ion core material particles are NMC. The one or more lithium supplement materials include lithium peroxide.

13. The method according to claim 9, wherein, The one or more lithium supplementary materials, the cathode catalyst, and the lithiation core material particles are present in powder form, and the method further includes: The one or more lithium supplemental materials are ground to a first average particle size; The cathode catalyst is ground to a second average particle size; and The cathode material is formed by: mixing the ground one or more lithium-supplementing materials with the ground cathode catalyst and the lithiation core material particles, and coating the lithiation core material particles. Wherein, the first average particle size and the second average particle size are 1 μm or smaller.

14. The method according to claim 13, wherein, The one or more lithium-replenishing materials mentioned are lithium peroxide.

15. The method according to claim 13 or 14, wherein, The lithium-ion core material particles have a third average particle size of 1 to 20 μm.

16. The method according to claim 13 or 14, wherein, The passivation layer is electrically conductive in both ionic and electronic terms.

17. A lithium-ion battery, comprising: A positive electrode includes a cathode current collector coated with a cathode material layer, wherein the cathode material layer comprises: A lithium compound core particle coated with a surface coating comprising a lithium-supplementing material and a lithium-based active cathode catalyst, wherein the surface coating coats and adheres to the lithium compound core particle; wherein the lithium compound core particle is further coated with a passivation layer, the passivation layer coating the surface coating, and the surface coating is located between the lithium compound core particle and the passivation layer; and Polyvinylpyrrolidone adhesive; negative electrode; A partition is disposed between the positive electrode and the negative electrode; and Electrolytes.

18. The lithium-ion battery according to claim 17, wherein, The lithium replenishing material is lithium peroxide or lithium aluminum oxide.

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