Cathode active materials comprising a lithium-containing ceramic coating and methods for making thereof

Abstract

Provided are cathode active materials with a lithium-containing ceramic coating and methods of making thereof. The method can include mixing an inorganic acid or oxide with a cathode active material comprising free lithium to form a mixture; and heating the mixture to react the inorganic acid or oxide with the free lithium to form a lithium containing ceramic coating, wherein the lithium containing ceramic coating coats the active material within the mixture to form a cathode active material with a lithium-containing ceramic coating.

Description

[0001]AttyDktNo.: ESS-L3-8134 WO CATHODE ACTIVE MATERIALS COMPRISING A LITHIUM-CONTAINING CERAMIC COATING AND METHODS FOR MAKING THEREOF FIELD The present disclosure relates to cathode coating materials, and in particular, cathode active materials comprising a lithium-containing ceramic coating and methods of making thereof. BACKGROUND Cathode active materials (such as lithium nickel-cobalt-aluminum oxide (NCA) or lithium nickel manganese cobalt (NMC)) are typically formed using a two-step process that includes co-precipitation and calcination (including both lithiation and oxidation) with a lithium compound. Co-precipitation includes nucleation, primary particle growth, and agglomeration to form secondary particles. Oftentimes, free (or residual) lithium remains with the cathode active material after calcination. This free lithium is usually alkaline (e.g., lithium hydroxide (LiOH), lithium carbonate (Li2CO3), or lithium oxide (Li2O)). The presence of alkaline-free lithium along with the cathode active material can reduce electrode slurry quality, compromise battery cyclability, and cause various safety concerns in a battery. SUMMARY Provided are cathode active materials comprising a lithium-containing ceramic coating and methods of making thereof. As explained above, cathode active materials synthesized via co-precipitation and calcination methods often include free (or residual) alkaline lithium. This free (or residual) alkaline lithium can be associated with safety concerns caused by the cathode active material reacting with the electrolyte of a battery and / or side reactions between the cathode active material and oxygen, particularly in cathode active materials with relatively higher amounts of nickel. Coating the cathode active material with a lithium-containing ceramic coating, as described herein, can mitigate these concerns. Other benefits of these cathode active materials comprising a lithium-containing ceramic coating can include an improvement in the electrode slurry stability and cycling stability of the cathode active material. AttyDktNo.: ESS-L3-8134 WO The cathode active materials comprising a lithium-containing ceramic coating as disclosed herein can include a cathode active material core that is at least partially surrounded by a lithium-containing ceramic coating. In some embodiments, the lithium- containing ceramic coating may be prepared by reacting an inorganic acid or oxide with the free (or residual) lithium of the cathode active material. The cathode active materials comprising a lithium-containing ceramic coating as described herein may be prepared using the methods and processes described herein. Specifically, the methods and processes for preparing cathode active materials comprising a lithium-containing ceramic coating can include a dry (or solvent-less, solvent-free) coating process. Other coating processes can include wet coating processes and deposition methods such as physical or chemical deposition. However, the dry coating processes described here can eliminate a washing step that is otherwise required in a wet coating process. Eliminating this washing step can reduce the capital investment on equipment and environmental control, and significantly reduces the material loss. In some embodiments, a cathode active material including a lithium-containing ceramic coating includes a plurality of particles, each particle of the plurality of particles comprising: a core comprising a cathode active material; and a lithium-containing ceramic coating at least partially surrounding the core, wherein the lithium-containing ceramic coating comprises one or more of LiSbO3,Li5SbO5,Li2SbO4, LiBiO3, Li5BiO5, Li3BiO4,Li6SeO6, Li4SeO5, Li2SeO4, Li6TeO6, Li4TeO5, Li2TeO4, Li4SiO4, Li2SiO3, LiGeO2,Li2Ge4O9, Li4GeO4,,Li2SnO3,,Li4SnO4, LiSbO3,Li5SbO5,Li2SbO4, LiBiO3, Li5BiO5, Li3BiO4, Li6SeO6, Li4SeO5, Li2SeO4, Li6TeO6, Li4TeO5, or Li2TeO4. In some embodiments, the cathode active material comprises 35-61 wt. % nickel. In some embodiments, the cathode active material comprises nickel-manganese-cobalt (NMC) or nickel-cobalt-aluminum (NCA). In some embodiments, the lithium-containing ceramic coating is doped with one or more of niobium, tantalum, zirconium, titanium, boron, aluminum, or gallium. In some embodiments, an electrode includes any of the cathode active materials disclosed herein. In some embodiments, the electrode further comprises 0.1-10 wt. % carbon black or carbon nanotubes and 0.1-10 wt. % polymer binder. In some AttyDktNo.: ESS-L3-8134 WO embodiments, a rechargeable battery includes any of the electrodes disclosed herein. In some embodiments, the rechargeable battery includes a lithium metal anode. In some embodiments, a method for making a cathode active material with a lithium-containing ceramic coating includes mixing an inorganic acid or oxide with a cathode active material comprising free lithium to form a mixture, wherein the inorganic acid or oxide comprises one or more of silicic acid (H2SiO3), metastannic acid (H2SnO3), metagermanic acid (H2GeO3), telluric acid (Te(OH)6), antimony trioxide (Sb2O3), germanium dioxide (GeO2), stannic oxide (SnO2), or dibismuth trioxide (Bi2O3); and heating the mixture to react the inorganic acid or oxide with the free lithium to form a lithium containing ceramic coating, wherein the lithium containing ceramic coating coats the active material within the mixture to form a cathode active material with a lithium- containing ceramic coating. In some embodiments, the inorganic acid or oxide has a pKa of less than 13. In some embodiments, the inorganic acid or oxide has a pKa of greater than 8. In some embodiments, a compound element of the inorganic acid or oxide that is not oxygen or hydrogen is in a highest oxidation state. In some embodiments, a melting point of the inorganic acid or oxide is lower than a reaction temperature of a reaction between the inorganic acid or oxide and the free lithium. In some embodiments, the melting point of the inorganic acid or oxide is between 100 and 250℃. In some embodiments, the reaction temperature of a reaction between the inorganic acid or oxide and the free lithium is between 450 and 600℃. In some embodiments, the inorganic acid or oxide has a pKa of greater than 8, a compound element that is not oxygen or hydrogen of the inorganic acid or oxide is in a highest oxidation state, and a melting point of the inorganic acid or oxide is lower than a reaction temperature of a reaction between the inorganic acid or oxide and the free lithium. In some embodiments, the free lithium comprises one or more of lithium hydroxide (LiOH), lithium carbonate (Li2CO3), or lithium oxide (Li2O). In some embodiments, mixing comprises mixing an inorganic acid or oxide with a cathode active material comprising free lithium and a dopant to form a mixture. In some embodiments, the dopant comprises one or more of niobium pentoxide (Nb2O5), tantalum pentoxide (Ta2O5), zirconium oxide (Zr2O), titanium dioxide (TiO2), boric acid (B(OH)3), aluminum hydroxide (Al(OH)3), gallium (III) oxide (Ga2O3), or gallium (III) hydroxide Ga(OH)3. In some embodiments, mixing comprises mixing 1-5 AttyDktNo.: ESS-L3-8134 WO wt. % inorganic acid or oxide. In some embodiments, mixing comprises mixing 95-99 wt. % cathode active material. In some embodiments, mixing comprises mixing 0.1-0.5 wt. % dopant. In some embodiments, heating the mixture takes place in a carbon dioxide-free environment. In some embodiments, heating the mixture occurs at a temperature between 200℃ and 700℃. In some embodiments, heating the mixture comprises heating for 2-5 hours. In some embodiments, a cathode active material including a lithium-containing ceramic coating prepared by a method includes mixing an inorganic acid or oxide with a cathode active material comprising free lithium to form a mixture, wherein the inorganic acid or oxide comprises one or more of silicic acid (H2SiO3), metastannic acid (H2SnO3), metagermanic acid (H2GeO3), telluric acid (Te(OH)6), antimony trioxide (Sb2O3), germanium dioxide (GeO2), stannic oxide (SnO2), or dibismuth trioxide (Bi2O3); and heating the mixture to react the inorganic acid or oxide with the free lithium to form a lithium containing ceramic coating, wherein the lithium containing ceramic coating coats the active material within the mixture to form a cathode active material with a lithium- containing ceramic coating. In some embodiments, any one or more of the features, characteristics, or elements discussed above with respect to any of the embodiments may be incorporated into any of the other embodiments mentioned above or described elsewhere herein. BRIEF DESCRIPTION OF THE FIGURES FIG.1 shows a process 100 for coating cathode active materials with a lithium- containing ceramic material, according to some embodiments; FIG.2 shows an x-ray powder diffraction of a coating material formed from lithium hydroxide and silicic acid, according to some embodiments; FIG.3 shows an x-ray powder diffraction of a coating material formed from lithium hydroxide and telluric acid (Te(OH)6), according to some embodiments; FIG.4A shows discharge capacities and first coulombic energy values of half cells prepared using coated cathode active materials as described herein (specifically, coated AttyDktNo.: ESS-L3-8134 WO NMC811 prepared using silicic acid) and half cells prepared using uncoated cathode active materials (specifically, NMC811), according to some embodiments; FIG.4B shows the capacity retention of the same two half-cells depicted in FIG. 4A, according to some embodiments; FIG.5A shows the pH of a coated cathode active material (i.e., coated NMC811 prepared using silicic acid) and uncoated cathode active material (i.e., NMC811 uncoated) as measured by ASTM D1512-21 method B, according to some embodiments; FIG.5B shows the slurry stability of the coated cathode active material and uncoated cathode active material (i.e., viscosity (Pascal-second) versus angular frequency (shear, s-1), according to some embodiments; FIG.6A shows discharge capacities and the first coulombic efficiencies of half cells prepared using coated cathode active materials as described herein (specifically, coated NMC811 prepared using telluric acid) and half cells prepared using uncoated cathode active materials (specifically, NMC811), according to some embodiments; and FIG.6B shows the capacity retention of the same two half-cells depicted in FIG. 6A, according to some embodiments. DETAILED DESCRIPTION Provided are cathode active materials comprising a lithium-containing ceramic coating and methods of making thereof. Cathode active materials are often formed using a two-step process that includes co-precipitation and calcination. As a result of this process, free or residual lithium often remains with the synthesized cathode active material. However, this free (or residual) lithium can be associated with various safety concerns due to side reactions with the electrolyte, gas generation and cell swelling upon charging to over 4.0 V. Accordingly, the cathode active material described herein can include a lithium-containing ceramic coating that neutralizes the free (or residual) alkaline lithium and alleviates many of these safety concerns, without compromising performance. Other benefits include an improvement in the surface stability and / or cycling stability of the cathode active material, a reduced pH to avoid or alleviate slurry gelation, and lower AttyDktNo.: ESS-L3-8134 WO surface resistance. The cathode active material comprising a lithium-containing ceramic coating as disclosed herein can include a cathode active material core that is at least partially surrounded by a lithium-containing ceramic coating. In some embodiments, the lithium-containing ceramic coating may be prepared by reacting an inorganic acid or oxide with the free (or residual) lithium of the cathode active material. In some embodiments, the methods and processes for preparing cathode active materials comprising a lithium-containing ceramic coating include a dry (or solvent-less, solvent-free) coating process. The dry coating processes provided herein can eliminate a washing step that is otherwise required in a wet coating process. Additionally, deposition methods (physical or chemical deposition) can include a soluble or gaseous coating material. Conversely, the dry coating methods described herein do not necessarily need a soluble / gaseous material, but instead can use a material that has a low melting point and is capable of reacting directly with the alkaline lithium salts. As used herein, the dry coating process may be interchangeably referred to as a “refiring” or “solvent-less” or “solvent- free” process. Also described herein are electrodes comprising the coated cathode active materials described and methods of making thereof, and rechargeable batteries comprising said electrodes and methods of making thereof. Described below are (1) Processes for Coating Cathode Active Materials with Lithium-Containing Ceramic Coatings; (2) Cathode Active Materials Comprising Lithium-Containing Ceramic Coatings; (3) Characterization of Cathode Active Materials Comprising Lithium-Containing Ceramic Coatings formed from the Dry Coating Processes Described Herein; (4) Preparing Electrodes and Batteries from Cathode Active Materials Comprising Lithium-Containing Ceramic Coatings; and (5) Electrochemical Performance. 1. Processes for Coating Cathode Active Materials with Lithium-Containing Ceramic Materials The cathode active materials comprising a lithium-containing ceramic coating as described herein may be coated with lithium-containing ceramic materials using a dry coating or “refiring” process. This process may also be referred to as “solventless” or AttyDktNo.: ESS-L3-8134 WO “solvent-free.” FIG.1 shows a process 100 for coating cathode active materials with a lithium-containing ceramic material. During the process, an inorganic acid and / or oxide is mixed with a cathode active material. The inorganic acid and / or oxide can react with lithium of the cathode active material to form a cathode active material coated with a lithium-containing ceramic material. In some embodiments, the inorganic acid and / or oxide can react with free lithium (e.g., lithium hydroxide) remaining from the cathode active material synthesis process. In some embodiments, the inorganic acid and / or oxide can react with lithium of the cathode active material. In some embodiments, the inorganic acid and / or oxide can react free lithium (e.g., lithium hydroxide, alkaline lithium) remaining from the cathode active material synthesis process and with lithium of the cathode active material. As used herein, the term “free lithium” is defined as lithium (often in the form of a lithium salt) that is not integrated or bound within the cathode active material and can be dissolved in water. Specifically, at step 102, one or more inorganic oxides and / or one or more acids can be mixed with a cathode active material. In some embodiments, 1-5 wt. % inorganic oxide and / or acids may be mixed with the cathode active material. In some embodiments, less than or equal to 5, less than or equal to 4, less than or equal to 3, or less than or equal to 2 wt. % inorganic oxide and / or acids may be mixed with the cathode active material. In some embodiments, greater than or equal to 1, greater than or equal to 2, greater than or equal to 3, or greater than or equal to 4 wt. % inorganic oxide and / or acids may be mixed with the cathode active material. In some embodiments, 95-99 wt. % cathode active material is mixed with the inorganic oxide and / or acid. In some embodiments, less than or equal to 99 wt. %, less than or equal to 98 wt. %, less than or equal to 97 wt. %, or less than or equal to 96 wt. % cathode active material is mixed with the inorganic oxide and / or acid. In some embodiments, greater than or equal to 95 wt. %, greater than or equal to 96 wt. %, greater than or equal to 97 wt. %, or greater than or equal to 98 wt. % cathode active material is mixed with the inorganic oxide and / or acid. These weight percentages can refer to the weight percent of the given compound with respect to the total mixture. AttyDktNo.: ESS-L3-8134 WO Suitable inorganic oxide and / or acids may include, but are not limited to, silicic acid (H2SiO3), metastannic acid (H2SnO3), metagermanic acid (H2GeO3), telluric acid (Te(OH)6), antimony trioxide (Sb2O3), germanium dioxide (GeO2), stannic oxide (SnO2), or dibismuth trioxide (Bi2O3). In some embodiments, the cathode active material can include ternary nickel-manganese-cobalt (NMC), nickel-cobalt-aluminum (NCA), lithium- rich layered oxides, manganese-rich layered oxides, and / or LiNi0.5Mn1.5O2. The cathode active materials used in the process herein can comprise an amount of alkaline lithium residual on the surface remaining from the calcination process used in forming the cathode active material. This alkaline lithium residual (or free lithium) can react with the inorganic oxide and / or acids to form the coating on the cathode active material. The alkaline lithium residual material may be in the form of lithium hydroxide (LiOH), lithium carbonate (Li2CO3), or lithium oxide (Li2O). In some embodiments, suitable inorganic acids / oxides have a pKa that is less than 13. In some embodiments, suitable inorganic acids / oxides have a pKa that is greater than 8. Other inorganic acid properties that can help identify a suitable inorganic acid or oxide can include the oxidation state, the melting point, and the reaction temperature (e.g., to avoid proton exchange). Suitable inorganic acids and / or oxides can also be compatible with cathode materials and should ensure that the reaction will perform at the selected temperature and time. Table 1, below, shows various inorganic acids / oxide and their respective pKa, oxidation states, melting points, and reaction temperatures. Inorganic pKa Oxidation state of Melting point Reaction acid / oxide element other than (oC) temperature O and H (oC) H2SiO3 8.59 +4 (highest) 203-205 478 Te(OH)68.8 +6 (highest) 136 ≥500 H2SnO3 10 +4 (highest) NA ≥500 H2GeO310.32 +4 (highest) NA ≥500 Ga(OH)3 8.59 +3 (highest) NA ≥500 Table 1. The properties of the inorganic acids and oxides of selection In some embodiments, the pKa of the inorganic acid and / or oxide is between 8 and 12. The pKa of the inorganic acid and / or oxide can be less than or equal to 12, less than or AttyDktNo.: ESS-L3-8134 WO equal to 11, less than or equal to 10, or less than or equal to 9. The pKa of the inorganic acid and / or oxide can be greater than or equal to 8, greater than or equal to 9, greater than or equal to 10, or greater than or equal to 11. A pKa of greater than 8 can prevent or minimize proton exchange during the reaction. In some embodiments, the oxidation state of the inorganic acid and / or oxide is the highest. The oxidation state of the inorganic acid or oxide as used herein is defined as the oxidation state of the compound element other than oxygen or hydrogen. In some embodiments, if the oxidation state of the inorganic oxide or acid is not in its highest state, it might cause or encourage undesirable reactions (e.g., redox reactions) with the nickel, manganese, or cobalt of the cathode active material (or deactivate the transition metal), which can negatively impact the capacity. An inorganic oxide or acid in its highest oxidation state can encourage a reaction only with the residual lithium, not the cathode active material. In some embodiments, the melting point of the inorganic acid and / or oxide is relatively low. In some embodiments, the melting point of the inorganic acid / oxide may be between 100 and 500℃ or between 100 and 250℃. The melting point of the inorganic acid / oxide may be less than or equal to 500, less than or equal to 450, less than or equal to 400, less than or equal to 350, less than or equal to 300, less than or equal to 250, less than or equal to 225, less than or equal to 200, less than or equal to 175, less than or equal to 150 or less than or equal to 125℃. The melting point of the inorganic acid / oxide may be greater than or equal to 100, greater than or equal to 125, greater than or equal to 150, greater than or equal to 175, greater than or equal to 200, greater than or equal to 225℃, greater than or equal to 250℃, greater than or equal to 300℃, greater than or equal to 350℃, greater than or equal to 400℃, or greater than or equal to 450℃. When the inorganic oxide or acid has a relatively low melting temperature, it can generate a higher contact area with the cathode active material, forming a more homogenous coating. In some embodiments, the inorganic oxide or acid can generate a higher contact area with the cathode active material and form a more homogenous coating when the melting point is lower than the reaction temperature. AttyDktNo.: ESS-L3-8134 WO In some embodiments, the reaction temperature (i.e., the temperature of the reaction between the inorganic acid and / or oxide with the lithium) is between 450 and 800℃ or between 450 and 600℃. In some embodiments, the reaction temperature can be less than or equal to 800, less than or equal to 750, less than or equal to 700, less than or equal to 650, less than or equal to 600, less than or equal to 550, or less than or equal to 500℃. In some embodiments, the reaction temperature is greater than or equal to 450, greater than or equal to 500, greater than or equal to 550, greater than or equal to 600, greater than or equal to 650, greater than or equal to 700, or greater than or equal to 750℃. In some embodiments, the reaction temperature of the may be 478℃. The reaction temperature can also be greater than or equal to 500℃ in some embodiments. In some embodiments, the inorganic acid and / or oxide can include at least one of the following criteria: (1) be in its highest oxidation state; (2) have a pKa that is greater than 8; or (3) have a melting point that is lower than the reaction temperature to ensure that the inorganic acid and / or oxide selectively reacts with the free alkaline lithium and little, if any, lithium of the cathode active material. In some embodiments, the inorganic acid and / or oxide includes two or more of the above criteria to ensure that the inorganic acid and / or oxide selectively reacts with the free alkaline lithium and little, if any, lithium of the cathode active material. In some embodiments, the inorganic acid and / or oxide includes all three of the above criteria to ensure that the inorganic acid and / or oxide selectively reacts with the free alkaline lithium and little, if any, lithium of the cathode active material. In some embodiments, the cathode active materials can include nickel-manganese- cobalt (NMC) and / or nickel-cobalt-aluminum (NCA) cathode active materials. In some embodiments, the cathode active material used herein may be characterized as a high- nickel cathode active material. In some embodiments, a high-nickel cathode active material may comprise 35 wt.% nickel or greater. In some embodiments, a high-nickel cathode active material may comprise 48 wt. % nickel or greater in the cathode active material. In some embodiments, a cathode active material used herein may comprise from 35-61 wt. % nickel. The cathode active materials used herein may comprise greater than or equal to 35 wt. %, greater than or equal to 36 wt.%, greater than or equal to 40 wt. %, greater than or equal to 45 wt. %, greater than or equal to 48 wt. %, greater than or equal AttyDktNo.: ESS-L3-8134 WO to 50 wt. %, greater than or equal to 52 wt. %, greater than or equal to 54 wt. %, greater than or equal to 56 wt. %, or greater than or equal to 58 wt. % nickel. The cathode active material used herein may comprise less than or equal to 61 wt. %, less than or equal to 60 wt. %, less than or equal to 58 wt. %, less than or equal to 56 wt. %, less than or equal to 54 wt. %, less than or equal to 52 wt. %, less than or equal to 50 wt. %, less than or equal to 48 wt. %, less than or equal to 45 wt. %, or less than or equal to 40 wt. % nickel. In some embodiments, a dopant may be added to the inorganic oxide and / or acid and cathode active material mixture. The dopant may be added to the mixture in an amount of 0.1-0.5 wt. % of the total mixture. In some embodiments, less than or equal to 0.5, less than or equal to 0.4, less than or equal to 0.3, or less than or equal to 0.2 wt. % dopant of the total mixture may be added to the inorganic oxide and / or acid and cathode active material mixture. In some embodiments, greater than or equal to 0.1, greater than or equal to 0.2, greater than or equal to 0.3, or greater than or equal to 0.4 wt. % dopant of the total mixture may be added to the inorganic oxide and / or acid and cathode active material mixture. In some embodiments, no dopant may be mixed with the inorganic oxide and / or acid and cathode active material. In embodiments in which a dopant is used, suitable dopants may include, but are not limited to, niobium pentoxide (Nb2O5), tantalum pentoxide (Ta2O5), zirconium oxide (Zr2O), titanium dioxide (TiO2), boric acid (B(OH)3), aluminum hydroxide (Al(OH)3), gallium (III) oxide (Ga2O3), or gallium (III) hydroxide Ga(OH)3. At step 102, the inorganic oxide and / or acid is mixed with the cathode active material and optionally a dopant using an acoustic mixing process. In some embodiments, the acoustic mixing process occurs at a constant force. For example, the acoustic mixing process can occur at a consistent force of 40-100 times gravity. The acoustic mixing process can occur at a consistent force of less than or equal to 100, less than or equal to 90, less than or equal to 80, less than or equal to 70, less than or equal to 60, or less than or equal to 50 times gravity. The acoustic mixing process can occur at a consistent force of greater than or equal to 40, greater than or equal to 50, greater than or equal to 60, greater than or equal to 70, greater than or equal to 80, or greater than or equal to 90 times gravity. AttyDktNo.: ESS-L3-8134 WO In some embodiments, the acoustic mixing process can include multiple stages, wherein each mixing stage takes place at a different mixing force. For example, the acoustic mixing process may include 2, 3, 4, or 5 separate stages. In some embodiments, each stage is characterized by a progressively increasing mixing force. In some embodiments, each stage is characterized by a progressively decreasing mixing force. In some embodiments, the multiple stages alternate between two different mixing forces. In some embodiments, the acoustic mixing process occurs at progressively increasing mixing forces of 50 times gravity, 60 times gravity, and 70 times gravity. In embodiment in which the acoustic mixing process includes multiple stages, each stage may be between 30 seconds and 5 minutes or between 30 seconds and 2 minutes in length. Each stage may be less than or equal to 5 minutes, less than or equal to 4 minutes, less than or equal to 3 minutes, less than or equal to 2 minutes or less than or equal to 1 minute in length. Each stage may be greater than or equal to 30 seconds, greater than or equal to 1 minute, greater than or equal to 2 minutes, greater than or equal to 3 minutes, or 4 greater than or equal to minutes in length. In some embodiments, the length of each mixing stage is the same. In some embodiments, the lengths of each mixing stage may vary. In some embodiments, the mixing process includes three different mixing stages, each 1 minutes in length. The total length of the mixing process (either the total mixing length at a consistent mixing force or the total mixing length of multiple stages combined) may be between 1 and 20 minutes or between 2 and 4 minutes. The total length of the mixing process may be less than or equal to 20 minutes, less than or equal to 15 minutes, less than or equal to 10 minutes, less than or equal to 9 minutes, less than or equal to 8 minutes, less than or equal to 7 minutes, less than or equal to 6 minutes, less than or equal to 5 minutes, less than or equal to 4 minutes, less than or equal to 3 minutes, or less than or equal to 2 minutes. The total length of the mixing process may be greater than or equal to 1 minutes, greater than or equal to 2 minutes, greater than or equal to 3 minutes, greater than or equal to 4 minutes, greater than or equal to 5 minutes, greater than or equal to 6 minutes, greater than or equal to 7 minutes, greater than or equal to 8 minutes, greater than or equal to 9 minutes, greater than or equal to 10 minutes, or greater than or equal to 15 minutes. After mixing, the mixture can be transferred to a heat-resistant vessel (e.g., alumina crucible) and / or placed in furnace (e.g., tube furnace). AttyDktNo.: ESS-L3-8134 WO At step 104, the mixture is heat treated in the heat-resistant vessel to form a coated cathode active material. In some embodiments, the mixture is heated in a carbon dioxide- free environment. A carbon dioxide-free environment is defined as an environment comprising 0.001% or less carbon dioxide. For example, the furnace may be purged for a period (e.g., 10 minutes) to remove all carbon dioxide. In some embodiments, the mixture may be heated in an atmospheric environment. In some embodiments, the mixture is heated at a temperature between 200℃ and 700℃. The mixture can be heated at a temperature less than or equal to 700℃, less than or equal to 600℃, less than or equal to 500℃, less than or equal to 400℃, or less than or equal to 300℃. The mixture can be heated at a temperature greater than or equal to 200℃, greater than or equal to 300℃, greater than or equal to 400℃, greater than or equal to 500℃, or greater than or equal to 600℃. In some embodiments, the mixture is heated at a temperature of 500℃. In some embodiments, the mixture is heated for a length of time that is between 1 and 5 hours. The mixture can be heated for a length of time that is less than or equal to 5 hours, less than or equal to 4 hours, less than or equal to 3 hours, or less than or equal to 2 hours. The mixture can be heated for a length of time that is greater than or equal to 1 hour, greater than or equal to 2 hours, greater than or equal to 3 hours, or greater than or equal to 4 hours. In some embodiments, the mixture is heated for 2 hours. 2. Cathode Active Materials Comprising a Lithium-Containing Ceramic Coating Provided herein are cathode-active materials comprising a lithium-containing ceramic coating. In some embodiments, the cathode active materials comprising a lithium- containing ceramic coating can be prepared according to the processes and methods described herein. The cathode active materials comprising a lithium-containing ceramic coating may comprise a cathode active material core particle at least partially surrounded by or coated with a lithium-containing ceramic material. In some embodiments, at least about 5%, at least about 10%, at least about 15%, at least about 20%, at least about 25%, at least about 30%, at least about 35%, at least about 40%, at least about 50%, at least about 60%, at AttyDktNo.: ESS-L3-8134 WO least about 65%, at least about 70%, at least about 75%, at least about 80%, at least about 85%, at least about 90%, at least about 95%, at least about 99%, or at least about 100% of the surface of a cathode active material (i.e., core particle(s)) can be coated with a lithium- containing ceramic material (i.e., shell of core). Suitable cathode active materials are described above in Section 1. The lithium-containing ceramic coating may comprise one or more of LiSbO3,Li5SbO5,Li2SbO4, LiBiO3, Li5BiO5, Li3BiO4, Li6SeO6, Li4SeO5, Li2SeO4, Li6TeO6,Li4TeO5, Li2TeO4, Li4SiO4, Li2SiO3, LiGeO2, Li2Ge4O9, Li4GeO4, Li2SnO3,,Li4SnO4,LiSbO3,Li5SbO5,Li2SbO4, LiBiO3, Li5BiO5, Li3BiO4, Li6SeO6, Li4SeO5, Li2SeO4, Li6TeO6, Li4TeO5, or Li2TeO4. In some embodiments, lithium-containing ceramic coating is doped with one or more of niobium, tantalum, zirconium, titanium, boron, aluminum, or gallium. In some embodiments, the lithium-containing ceramic coating is formed when free lithium (e.g., alkaline lithium) reacts with an inorganic oxide or acid, as described above in Section 1. 3. Characterization of Cathode Active Materials Comprising a Lithium- Containing Ceramic Coating formed from the Dry Coating Processes Described Herein X-ray powder diffraction (XRD) on a D8 ADVANCE powder diffractometer (Bruker Inc.) using a Cu Kα anode as the X-ray source (λ=1.54060 Å) was used to identify the speciation of the reaction products between the inorganic acids / oxides with LiOH. The thermogravimetric analysis (TGA) was performed on Sta 449f3. FIG.2 shows an x-ray powder diffraction of a coating material formed from lithium hydroxide monohydrate and silicic acid. Specifically, the lithium hydroxide and silicic acid were combined at a molar ratio of 4:1 and heated at 500oC. The XRD confirms the reaction between the lithium hydroxide and silicic acid. FIG.3 shows an x-ray powder diffraction of a coating material formed from lithium hydroxide monohydrate and telluric acid (Te(OH)6). Specifically, the lithium AttyDktNo.: ESS-L3-8134 WO hydroxide and telluric acid were combined at a molar ratio of 6:1 and heated at 500oC. The XRD confirms the reaction between lithium hydroxide and telluric acid. 4. Preparing Electrodes and Batteries from Cathode Active Materials Comprising a Lithium-Containing Ceramic Coating In some embodiments, an electrode (i.e., cathode) in the form of a laminate may be prepared by combining the cathode active material comprising a lithium-containing ceramic coating described herein with carbon black and / or carbon nanotubes and a binder. In some embodiments, the binder can be a polymer binder. In some embodiments, the electrode may comprise 0.1-10 wt. % carbon black and / or carbon nanotubes. The electrode may comprise less than or equal to 10 wt. %, less than or equal to 9 wt. %, less than or equal to 8 wt. %, less than or equal to 7 wt. %, less than or equal to 6 wt. %, less than or equal to 5 wt. %, less than or equal to 4 wt. %, less than or equal to 3 wt. %, less than or equal to 2 wt. %, or less than or equal to 1 wt. % carbon black and / or carbon nanotubes. The electrode may comprise greater than or equal to 0.1 wt. %, greater than or equal to 1 wt. %, greater than or equal to 2 wt. %, greater than or equal to 3 wt. %, greater than or equal to 4 wt. %, greater than or equal to 5 wt. %, greater than or equal to 6 wt. %, greater than or equal to 7 wt. %, greater than or equal to 8 wt. %, or greater than or equal to 9 wt. % carbon black and / or carbon nanotubes. In some embodiments, the electrode may comprise 0.1-10 wt. % binder. The electrode may comprise less than or equal to 10 wt. %, less than or equal to 9 wt. %, less than or equal to 8 wt. %, less than or equal to 7 wt. %, less than or equal to 6 wt. %, less than or equal to 5 wt. %, less than or equal to 4 wt. %, less than or equal to 3 wt. %, less than or equal to 2 wt. %, or less than or equal to 1 wt. % binder. The electrode may comprise greater than or equal to 0.1 wt. %, greater than or equal to 1 wt. %, greater than or equal to 2 wt. %, greater than or equal to 3 wt. %, greater than or equal to 4 wt. %, greater than or equal to 5 wt. %, greater than or equal to 6 wt. %, greater than or equal to 7 wt. %, greater than or equal to 8 wt. %, or greater than or equal to 9 wt. % binder. In some embodiments, the electrode may comprise 80-99.8 wt. % cathode active material comprising a lithium-containing ceramic coating described herein. The electrode may comprise less than or equal to 99.8 wt. %, less than or equal to 99.5 wt. %, less than AttyDktNo.: ESS-L3-8134 WO or equal to 99 wt. %, less than or equal to 98 wt. %, less than or equal to 97 wt. %, less than or equal to 95 wt. %, less than or equal to 90 wt. %, or less than or equal to 85 wt. % cathode active material comprising a lithium-containing ceramic coating described herein. The electrode may comprise greater than or equal to 80 wt. %, greater than or equal to 85 wt. %, greater than or equal to 90 wt. %, greater than or equal to 95 wt. %, greater than or equal to 96 wt. %, greater than or equal to 97 wt. %, greater than or equal to 98 wt. %, greater than or equal to 99 wt. %, or greater than or equal to 99.5 wt. % cathode active material comprising a lithium-containing ceramic coating described herein. In some embodiments, the cathode laminates may be used in coin cells (e.g., 2032 coin cell) with lithium metal as a counter electrode. The electrolyte may be liquid. For example, the electrolyte may comprise LiPF6. In some embodiments, the electrolyte may comprise 1.2 M of LiPF6 in ethylene carbonate / diethyl carbonate (vol: vol= 3:7) with 5 wt. % fluoroethylene carbonate. 5. Electrochemical Performance Specific electrochemical performance data is shown in FIGs.4A-4B and 6A-6B and described below. In some embodiments, the first discharge capacity of a half-cell prepared from the ceramic coated cathode active material is 205-215 mAh / g at cycles carried out between 2.9V and 4.3V at a rate of C / 20. In some embodiments, the cycles can be carried out at a rate of C / 20 followed by C / 10, C / 5, and C / 3. In some embodiments, the first discharge capacity of a half-cell prepared from ceramic-coated cathode active material (e.g., coated using silicic acid, according to the processes described herein) is greater than a first discharge capacity of a half-cell comprising non-coated cathode active material (e.g., NMC811) at cycles carried out between 2.9V and 4.3V at a rate of C / 20. In some embodiments, a half-cell prepared from coated cathode active material has a first coulombic energy of 95-97 % at cycles carried out between 2.9V and 4.3V at a rate of C / 20. In some embodiments, a half-cell prepared from the coated cathode active material has a first coulombic energy that is greater than the first coulombic energy of a half-cell comprising non-coated cathode active material at cycles carried out between 2.9V and 4.3V at a rate of C / 20. AttyDktNo.: ESS-L3-8134 WO In some embodiments, a half-cell prepared from ceramic coated cathode active material (e.g., coated using silicic acid, according to the processes described herein) may have a capacity retention (%) that is greater than that of a non-coated cathode active material (e.g., NMC811). EXAMPLES Example 1: NMC 811 (lithium nickel manganese cobalt) and between 1-5 wt.% silicic acid were introduced into a plastic container and mixed via acoustic mixing. The acoustic mixing was carried out at progressively increasing forces of 50 times, 60 times, and 70 times gravity, each for 1 minute. After mixing, the mixture was transferred to an alumina crucible and placed in a tube furnace. The tube was then purged to remove carbon dioxide for 10 minutes at room temperature and the mixture underwent heat treatment at 500℃ for 2- 5 hours to form a cathode active material with a lithium- containing ceramic coating. For electrode preparation, 1% of carbon black / carbon nanotube and 2% of PVDF binder were mixed with the above cathode active material with a lithium-containing ceramic coating to form a cathode laminate. The laminates were tested in 2032-coin cells using lithium metal as counter electrodes. The electrolyte consists of 1.2 M of LiPF6 in ethylene carbonate / diethyl carbonate (vol: vol= 3:7) with 5 wt% fluoroethylene carbonate. The cycles were carried out between 2.9V and 4.3V at a rate of C / 20. The charge and discharge curves of the compound of disclosure are illustrated from showing the characteristic charge-discharge curves of NMC 811, with varying charge and discharge capacities and Coulombic efficiencies in comparison with the coated NMC 811 synthesized using silicic acid (e.g., the above cathode active material with a lithium- containing ceramic coating). FIG.4A shows discharge capacities and first coulombic energy values of half cells prepared using uncoated NMC 811 and coated NMC811 prepared using silicic acid. FIG. 4B shows the capacity retention of the same two half cells. FIG.4A shows that the coated NMC811 has higher capacity and coulombic efficiency than that of the uncoated NMC811. FIG.4B shows that the coated NMC811 also has comparable capacity retention as compared to that of the uncoated NMC811. AttyDktNo.: ESS-L3-8134 WO A pH measurement was also performed by suspending the cathode materials (i.e., the uncoated NMC 811 and the coated NMC 811 prepared using silicic acid) in degassed deionized water and sonicating for 1 minute. The pH of the suspension was tested with a calibrated pH meter. FIG.5A shows the pH of a coated cathode active material (i.e., coated NMC811 prepared using silicic acid) and uncoated cathode active material (i.e., NMC811 uncoated) as measured by ASTM D1512-21, Method B, and FIG.5B shows the slurry stability of the coated cathode active material and uncoated cathode active material (i.e., viscosity (Pascal-second) versus angular frequency (shear, s-1)). The reduced pH of the coated cathode suggests that half of the free and alkaline lithium on the uncoated cathode are neutralized (as shown in FIG.5A). Example 2: NMC 811 (lithium nickel manganese cobalt) and between 1-5 wt.% telluric acid were introduced into a plastic container and mixed via acoustic mixing. The acoustic mixing was carried out at progressively increasing forces of 50 times, 60 times, and 70 times gravity, each for 1 minute. After mixing, the mixture was transferred to an alumina crucible and placed in a tube furnace. The tube was then purged to remove carbon dioxide for 10 minutes at room temperature and the mixture underwent heat treatment at 500℃ for 2- 5 hours to form a cathode active material with a lithium- containing ceramic coating. For electrode preparation, 1% of carbon black / carbon nanotube and 2% of PVDF binder were mixed with the above cathode active material with a lithium-containing ceramic coating to form a cathode laminate. The laminates were tested in 2032-coin cells using lithium metal as counter electrodes. The electrolyte consists of 1.2 M of LiPF6 in ethylene carbonate / diethyl carbonate (vol: vol= 3:7) with 5 wt% fluoroethylene carbonate. The cycles were carried out between 2.9V and 4.3V at a rate of C / 20. The charge and discharge curves of the compound of disclosure are illustrated from showing the characteristic charge-discharge curves of NMC 811, with varying charge and discharge capacities and Coulombic efficiencies in comparison with the coated NMC 811 synthesized using telluric acid (e.g., the above cathode active material with a lithium- containing ceramic coating). AttyDktNo.: ESS-L3-8134 WO FIG.6A shows discharge capacities and first coulombic energy values of half cells prepared using uncoated NMC 811 and coated NMC811 prepared using telluric acid. FIG. 6B shows the capacity retention of the same two half cells. FIG.6A shows that the coated NMC811 has higher capacity and coulombic efficiency than that of the uncoated NMC811. FIG.6B shows that the coated NMC811 also has comparable capacity retention as compared to that of the uncoated NMC811. Additional Definitions In this disclosure, while compositions and / or processes or methods are often described in terms of “comprising” various components or steps, the compositions and methods can also “consist essentially of” or “consist of” the various components or steps, unless stated otherwise. For example, a process consistent with aspects of the disclosed subject matter can comprise; alternatively, can consist essentially of; or alternatively, can consist of; the process steps indicated. The terms “a,” “an,” and “the” are intended to include plural alternatives, e.g., at least one, one or more, and one or more than one, unless otherwise specified. The terms “room temperature” or “ambient temperature” are used herein to describe any temperature from 15° C to 35° C wherein no external heat or cooling source is directly applied to the reaction vessel. Accordingly, the terms “room temperature” and “ambient temperature” encompass the individual temperatures and any and all ranges, subranges, and combinations of subranges of temperatures from 15° C to 35° C wherein no external heating or cooling source is directly applied to the reaction vessel. The term “atmospheric pressure” is used herein to describe an earth air pressure wherein no external pressure modifying means is utilized. Generally, unless practiced at extreme earth altitudes, “atmospheric pressure” is about 1 atmosphere (alternatively, about 14.7 psi or about 101 kPa). The term “about” means that amounts, sizes, formulations, parameters, and other quantities and characteristics are not and need not be exact, but may be approximate including being larger or smaller, as desired, reflecting tolerances, conversion factors, rounding off, measurement errors, and the like, and other factors known to those of skill in AttyDktNo.: ESS-L3-8134 WO the art. In general, an amount, size, formulation, parameter or other quantity or characteristic is “about” or “approximate” whether or not expressly stated to be such. The term “about” also encompasses amounts that differ due to different equilibrium conditions for a composition resulting from a particular initial mixture. Whether or not modified by the term “about,” the claims include equivalents to the stated quantities. When a numerical range of any type is disclosed or claimed herein (e.g., “ranging from…”, “in a range of from…”, “in the range of from…”, “in a range of from”, “in a range of”) the intent is to disclose or claim individually each possible number or ratio that such a range could reasonably encompass, including end points of the range as well as any sub-ranges and combinations of sub-ranges encompassed therein, unless otherwise specified. Embodiments disclosed herein can provide the materials listed as suitable for satisfying a particular feature of the embodiment delimited by the term “or.” For example, a particular feature of the disclosed subject matter can be disclosed as follows: Feature X can be A, B, or C. It is also contemplated that for each feature the statement can also be phrased as a listing of alternatives such that the statement “Feature X is A, alternatively B, or alternatively C” is also an embodiment of the present disclosure whether or not the statement is explicitly recited. Although any methods and materials similar or equivalent to those described herein can be used in the practice or testing of the subject matter described herein, the typical methods and materials are herein described. All publications and patents mentioned herein are incorporated herein by reference for the purpose of describing and disclosing, for example, the constructs and methodologies that are described in the publications, which can be used in connection with the presently described subject matter.

Claims

1. AttyDktNo.: ESS-L3-8134 WO CLAIMS 1. A cathode active material comprising a lithium-containing ceramic coating comprising: a plurality of particles, each particle of the plurality of particles comprising: a core comprising a cathode active material; and a lithium-containing ceramic coating at least partially surrounding the core, wherein the lithium-containing ceramic coating comprises one or more of LiSbO3,Li5SbO5,Li2SbO4, LiBiO3, Li5BiO5, Li3BiO4, Li6SeO6, Li4SeO5, Li2SeO4, Li6TeO6,Li4TeO5, Li2TeO4, Li4SiO4, Li2SiO3, LiGeO2, Li2Ge4O9, Li4GeO4,,Li2SnO3,,Li4SnO4,LiSbO3,Li5SbO5,Li2SbO4, LiBiO3, Li5BiO5, Li3BiO4, Li6SeO6, Li4SeO5, Li2SeO4, Li6TeO6, Li4TeO5, or Li2TeO4.

2. The cathode active material of claim 1, wherein the cathode active material comprises 35-61 wt. % nickel.

3. The cathode active material of any one of claims 1-2, wherein the cathode active material comprises nickel-manganese-cobalt (NMC) or nickel-cobalt-aluminum (NCA).

4. The cathode active material of any one of claims 1-3, wherein the lithium- containing ceramic coating is doped with one or more of niobium, tantalum, zirconium, titanium, boron, aluminum, or gallium.

5. An electrode comprising the cathode active material of any one of claims 1-4.

6. The electrode of claim 5, wherein the electrode further comprises 0.1-10 wt. % carbon black or carbon nanotubes and 0.1-10 wt. % polymer binder.

7. A rechargeable battery comprising the electrode of claim 5 or 6.

8. The rechargeable battery of claim 7, comprising a lithium metal anode.

9. A method for making a cathode active material with a lithium-containing ceramic coating, the method comprising: mixing an inorganic acid or oxide with a cathode active material comprising free lithium to form a mixture, wherein the inorganic acid or oxide comprises one or more of AttyDktNo.: ESS-L3-8134 WO silicic acid (H2SiO3), metastannic acid (H2SnO3), metagermanic acid (H2GeO3), telluric acid (Te(OH)6), antimony trioxide (Sb2O3), germanium dioxide (GeO2), stannic oxide (SnO2), or dibismuth trioxide (Bi2O3); and heating the mixture to react the inorganic acid or oxide with the free lithium to form a lithium containing ceramic coating, wherein the lithium containing ceramic coating coats the active material within the mixture to form a cathode active material with a lithium-containing ceramic coating.

10. The method of claim 9, wherein the inorganic acid or oxide has a pKa of less than 13.

11. The method of claim 10, wherein the inorganic acid or oxide has a pKa of greater than 8.

12. The method of any one of claims 9-11, wherein a compound element of the inorganic acid or oxide that is not oxygen or hydrogen is in a highest oxidation state.

13. The method of any of claims 9-12, wherein a melting point of the inorganic acid or oxide is lower than a reaction temperature of a reaction between the inorganic acid or oxide and the free lithium.

14. The method of claim 13, wherein the melting point of the inorganic acid or oxide is between 100 and 250℃.

15. The method of claim 12 or 14, wherein the reaction temperature of a reaction between the inorganic acid or oxide and the free lithium is between 450 and 600℃.

16. The method of any one of claims 9-15, wherein the inorganic acid or oxide has a pKa of greater than 8, a compound element that is not oxygen or hydrogen of the inorganic acid or oxide is in a highest oxidation state, and a melting point of the inorganic acid or oxide is lower than a reaction temperature of a reaction between the inorganic acid or oxide and the free lithium.

17. The method of any one of claims 9-16, wherein the free lithium comprises one or more of lithium hydroxide (LiOH), lithium carbonate (Li2CO3), or lithium oxide (Li2O). AttyDktNo.: ESS-L3-8134 WO 18. The method of any one of claims 9-17, wherein mixing comprises mixing an inorganic acid or oxide with a cathode active material comprising free lithium and a dopant to form a mixture.

19. The method of claim 18, wherein the dopant comprises one or more of niobium pentoxide (Nb2O5), tantalum pentoxide (Ta2O5), zirconium oxide (Zr2O), titanium dioxide (TiO2), boric acid (B(OH)3), aluminum hydroxide (Al(OH)3), gallium (III) oxide (Ga2O3), or gallium (III) hydroxide Ga(OH)3.

20. The method of any one of claims 9-19, wherein mixing comprises mixing 1-5 wt. % inorganic acid or oxide.

21. The method of any one of claims 9-20, wherein mixing comprises mixing 95-99 wt. % cathode active material.

22. The method of claim 21, wherein mixing comprises mixing 0.1-0.5 wt. % dopant.

23. The method of any one of claims 9-22, wherein heating the mixture takes place in a carbon dioxide-free environment.

24. The method of any one of claims 9-23, wherein heating the mixture occurs at a temperature between 200℃ and 700℃.

25. The method of any one of claims 9-24, wherein heating the mixture comprises heating for 2-5 hours.

26. A cathode active material comprising a lithium-containing ceramic coating prepared by a method comprising: mixing an inorganic acid or oxide with a cathode active material comprising free lithium to form a mixture, wherein the inorganic acid or oxide comprises one or more of silicic acid (H2SiO3), metastannic acid (H2SnO3), metagermanic acid (H2GeO3), telluric acid (Te(OH)6), antimony trioxide (Sb2O3), germanium dioxide (GeO2), stannic oxide (SnO2), or dibismuth trioxide (Bi2O3); and heating the mixture to react the inorganic acid or oxide with the free lithium to form a lithium containing ceramic coating, wherein the lithium containing ceramic coating AttyDktNo.: ESS-L3-8134 WO coats the active material within the mixture to form a cathode active material with a lithium-containing ceramic coating.

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