Notice of Pre-AIA or AIA Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Response to Amendment
The Amendment filed August 25, 2026 has been entered. Claims 1-20 remain pending in the application. Claims 9, 13, and 15 have been amended. Claims 19 and 20 have been added. All previous claim objections and 112 rejections have been overcome by amendments made to the claims. The examiner is applying new art to an original claim. Thus, this action is non-final.
Claim Rejections - 35 USC § 103
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis (i.e., changing from AIA to pre-AIA ) for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
The factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. Considering objective evidence present in the application indicating obviousness or nonobviousness.
Claims 1-5, 7, 8, 11, and 15-20 are rejected under 35 U.S.C. 103 as being unpatentable over Yamamoto et al. (US-20220190317-A1) in view of Ruan et al. (CN 102931384 A, as found in IDS dated 08/15/2024 and using machine translation for citation purposes as previously provided), hereafter referred to as Yamamoto and Ruan, respectively.
Regarding Claim 1, Yamamoto teaches a method for manufacturing a cathode electrode (“The precursor solution according to the present disclosure is a solution to be used for forming a material that coats a surface of an active material such as a positive electrode active material or a negative electrode active material in an electrode of a secondary battery,” paragraph 32), comprising:
a) dissolving one or more first organic isopropoxide precursors in a first solvent to form a mixture (“The precursor solution according to the present disclosure contains an organic solvent, a lithium oxoacid salt that shows solubility in the organic solvent, and an aluminum compound that shows solubility in the organic solvent,” paragraph 33; “Such an aluminum compound may be any as long as it shows solubility in the organic solvent constituting the precursor solution, and examples thereof include metal salt compounds such as aluminum nitrate, aluminum nitrate hydrate, aluminum orthophosphate, aluminum sulfate, aluminum sulfate hydrate, aluminum chloride, aluminum chloride hydrate, aluminum bromide, aluminum iodide, and aluminum fluoride, aluminum alkoxides such as aluminum tri-sec-butoxide, aluminum trimethoxide, aluminum triethoxide, aluminum tri-n-propoxide, aluminum triisopropoxide,” paragraph 59);
b) adding particles of cathode active material to the mixture (“The precursor solution according to the present disclosure contains the organic solvent, the lithium oxoacid salt, and the aluminum compound as described above, but may further contain particles of an active material such as a positive electrode active material,” paragraph 64);
c) heating the mixture to a first predetermined temperature for a first predetermined period to form a first metal oxide coating on the particles of the cathode active material (“the heating temperature in the heat treatment is preferably 50° C or higher and 250 °C or lower, more preferably 60 °C or higher and 230 °C or lower, and further more preferably 80 °C. or higher and 200 °C or lower,” paragraph 112; “the heating time in the heat treatment is preferably 10 minutes or more and 180 minutes or less, and more preferably 20 minutes or more and 120 minutes or less,” paragraph 113, indicating this first heating step is for a predetermined temperature and time period); and
e) calcining the particles of the cathode active material at a second predetermined temperature for a second predetermined period (“The heating temperature in this step is preferably 300° C. or higher and 600° C. or lower, more preferably 330° C. or higher and 570° C. or lower, and further more preferably 350° C. or higher and 570° C. or lower,” paragraph 128; “the heating time in this step is preferably 5 minutes or more and 240 minutes or less, more preferably 10 minutes or more and 180 minutes or less, and further more preferably 15 minutes or more and 120 minutes or less,” paragraph 129, indicating this second heating step is for a predetermined temperature and time period).
Yamamoto does not explicitly teach stirring in addition to heating in step c. However, Ruan teaches a method for forming a metal oxide layer on cathode electrode active material using organic isopropoxide precursors. Therein, Ruan teaches stirring after combining the cathode active material with the isopropoxide precursors (“lithium nickel cobalt manganese cathode material is added to an organic solution containing metal alkoxides, and after stirring,” paragraph 10).
It would have been obvious to a person having ordinary skill in the art before the effective filing date of the invention to take the method taught by Yamamoto and modify step c to also stir while heating the mixture, as taught by Ruan, in order to facilitate more efficient reaction and more efficient solvent removal.
Yamamoto also does not explicitly teach filtering the particles of the cathode active material from the mixture. However, Ruan teaches filtering after stirring (“and after stirring, filtration or evaporation,” paragraph 10). Additionally, Yamamoto acknowledges that the heating step may not remove all of the solvent, but the rest can be removed at a later step (“Even if not all the organic solvent is removed in this step, the remaining organic solvent can be sufficiently removed in a later step,” paragraph 109); step d taught by Ruan viably serves as that general later step taught by Yamamoto.
It would have been obvious to a person having ordinary skill in the art before the effective filing date of the invention to take the method taught by Yamamoto and include step d to filter the particles after heating and stirring, as taught by Ruan, in order to fully ensure that the particles are separated from any remaining organic solvent, as Yamamoto teaches.
Regarding Claim 2, Yamamoto modified by Ruan teaches the method of Claim 1, wherein Yamamoto further teaches that the first predetermined temperature is in a range from 80 °C to 250 °C (“the heating temperature in the heat treatment is preferably 50° C or higher and 250 °C or lower, more preferably 60 °C or higher and 230 °C or lower, and further more preferably 80 °C. or higher and 200 °C or lower,” paragraph 112). Please see MPEP § 2144.05: In the case where the claimed ranges "overlap or lie inside ranges disclosed by the prior art" a prima facie case of obviousness exists.
Regarding Claim 3, Yamamoto modified by Ruan teaches the method of claim 1, wherein the second predetermined temperature is in a range from 300 °C to 550 °C (“The heating temperature in this step is preferably 300 °C. or higher and 600 °C. or lower, more preferably 330 °C. or higher and 570 °C. or lower, and further more preferably 350 °C. or higher and 570 °C. or lower,” paragraph 128). Please see MPEP § 2144.05: In the case where the claimed ranges "overlap or lie inside ranges disclosed by the prior art" a prima facie case of obviousness exists.
Regarding Claim 4, Yamamoto modified by Ruan teaches the method of claim 1, wherein Yamamoto further teaches: the one or more first organic isopropoxide precursors are selected from a group consisting of aluminum (Al), titanium (Ti), niobium (Nb), zirconium (Zr), strontium (Sr), tin (Sn), barium (Ba), lithium (Li), antimony (Sb), lanthanum (La), samarium (Sm), germanium (Ge), gadolinium (Gd), yttrium (Y), scandium (Sc), boron (B), and cerium (Ce) (“The precursor solution according to the present disclosure contains an organic solvent, a lithium oxoacid salt that shows solubility in the organic solvent, and an aluminum compound that shows solubility in the organic solvent,” paragraph 33; “Such an aluminum compound may be any as long as it shows solubility in the organic solvent constituting the precursor solution, and examples thereof include metal salt compounds such as aluminum nitrate, aluminum nitrate hydrate, aluminum orthophosphate, aluminum sulfate, aluminum sulfate hydrate, aluminum chloride, aluminum chloride hydrate, aluminum bromide, aluminum iodide, and aluminum fluoride, aluminum alkoxides such as aluminum tri-sec-butoxide, aluminum trimethoxide, aluminum triethoxide, aluminum tri-n-propoxide, aluminum triisopropoxide,” paragraph 59);
and the cathode active material is selected from a group consisting of lithium- and manganese-rich (LMR), lithium iron phosphate (LFP), lithium manganese iron phosphate (LMFP), lithium nickel cobalt manganese aluminum (NCMA), lithium nickel manganese cobalt (NMC), lithium nickel oxide (LNO), lithium manganese oxide (LMO), and combinations thereof (“As the positive electrode active material, for example, a lithium composite oxide,” paragraph 66; “Examples of such a composite oxide include LiCoO2, LiNiO2, LiMn2O4, Li2Mn2O3, LiCr0.5Mn0.5O2, LiFePO4,” paragraph 66).
Regarding Claim 5, Yamamoto modified by Ruan teaches the method of claim 1, wherein Yamamoto teaches the one or more first organic isopropoxide precursors include a single organic isopropoxide precursor (“Such an aluminum compound may be any as long as it shows solubility in the organic solvent constituting the precursor solution, and examples thereof include metal salt compounds such as aluminum nitrate, aluminum nitrate hydrate, aluminum orthophosphate, aluminum sulfate, aluminum sulfate hydrate, aluminum chloride, aluminum chloride hydrate, aluminum bromide, aluminum iodide, and aluminum fluoride, aluminum alkoxides such as aluminum tri-sec-butoxide, aluminum trimethoxide, aluminum triethoxide, aluminum tri-n-propoxide, aluminum triisopropoxide,” paragraph 59) but not wherein the first metal oxide coating on the particles of the cathode active material includes a single-metal oxide coating, since Yamamoto teaches a composite metal oxide coating of lithium and aluminum, where the lithium is provided via a precursor that is not isopropoxide (“lithium oxoacid salt,” paragraph 9). However, Ruan teaches using a single organic isopropoxide precursor to form a first metal oxide coating on the particles of the cathode active material includes a single-metal oxide coating where the metal is aluminum (“Metal alkoxide sols are sols formed during stirring using at least one of tetrabutyl titanate, titanium isopropoxide, TiCl-NER8-, aluminum isopropoxide, aluminum nitrate, aluminum phosphate, zirconium acetate, and magnesium acetate as coating materials,” paragraph 13).
It would have been obvious to a person having ordinary skill in the art before the effective filing date of the invention to take the method taught by Yamamoto and modified by Ruan and further modify the method to simply exclude the lithium oxoacid salt in order to form a single-metal oxide coating with just aluminum isopropoxide, as taught by Ruan, in order to reduce costs and simplify the method while still applying a metal oxide coating to the active material.
Regarding Claim 7, Yamamoto modified by Ruan teaches the method of claim 1, wherein Yamamoto further teaches the first metal oxide coating on the particles of the cathode active material have a thickness in a range from 2nm to 50 nm (“the average thickness of the coating layer constituted by the material containing the precursor of the LiAl composite oxide is preferably 2 nm or more and 300 nm or less, more preferably 3 nm or more and 150 nm or less, and further more preferably 4 nm or more and 80 nm or less,” paragraph 95). Please see MPEP § 2144.05(I): In the case where the claimed ranges "overlap or lie inside ranges disclosed by the prior art" a prima facie case of obviousness exists.
Regarding Claim 8, Yamamoto modified by Ruan teaches the method of claim 1, wherein the first metal oxide coating on the particles of the cathode active material have a thickness in a range from 5nm to 20 nm (“the average thickness of the coating layer constituted by the material containing the precursor of the LiAl composite oxide is preferably 2 nm or more and 300 nm or less, more preferably 3 nm or more and 150 nm or less, and further more preferably 4 nm or more and 80 nm or less,” paragraph 95). Please see MPEP § 2144.05(I): In the case where the claimed ranges "overlap or lie inside ranges disclosed by the prior art" a prima facie case of obviousness exists.
Regarding Claim 11, Yamamoto modified by Ruan teaches the method of claim 1, but not wherein the first metal oxide coating includes a single metal oxide selected from a group consisting of Al, Ce, Ti, Sr, and Ge; instead, Yamamoto teaches a composite metal oxide coating of lithium and aluminum. However, Ruan teaches using a single organic isopropoxide precursor to form a first metal oxide coating on the particles of the cathode active material includes a single-metal oxide coating where the metal is aluminum (“Metal alkoxide sols are sols formed during stirring using at least one of tetrabutyl titanate, titanium isopropoxide, TiCl-NER8-, aluminum isopropoxide, aluminum nitrate, aluminum phosphate, zirconium acetate, and magnesium acetate as coating materials,” paragraph 13).
It would have been obvious to a person having ordinary skill in the art before the effective filing date of the invention to take the method taught by Yamamoto and modified by Ruan and further modify the method to simply exclude the lithium oxoacid salt in order to form a single-metal oxide coating with just aluminum isopropoxide, as taught by Ruan, in order to reduce costs and simplify the method while still applying a metal oxide coating to the active material.
Regarding Claim 15, Yamamoto teaches a method for manufacturing a cathode electrode, comprising:
a) dissolving one or more organic isopropoxide precursors in toluene to form a mixture (“the organic solvent constituting the precursor solution according to the present disclosure is preferably an organic solvent that is nonaqueous and contains one type or two or more types selected from the group consisting of n-butyl alcohol, ethylene glycol monobutyl ether, butylene glycol, hexylene glycol, pentanediol, hexanediol, heptanediol, toluene, o-xylene, p-xylene, hexane, heptane, and octane,” paragraph 42), wherein the one or more organic isopropoxide precursors are selected from a group consisting of aluminum (Al), titanium (Ti), niobium (Nb), zirconium (Zr), strontium (Sr), tin (Sn), barium (Ba), lithium (Li), antimony (Sb), lanthanum (La), samarium (Sm), germanium (Ge), gadolinium (Gd), yttrium (Y), scandium (Sc), boron (B), and cerium (Ce) (“The precursor solution according to the present disclosure contains an organic solvent, a lithium oxoacid salt that shows solubility in the organic solvent, and an aluminum compound that shows solubility in the organic solvent,” paragraph 33; “Such an aluminum compound may be any as long as it shows solubility in the organic solvent constituting the precursor solution, and examples thereof include metal salt compounds such as aluminum nitrate, aluminum nitrate hydrate, aluminum orthophosphate, aluminum sulfate, aluminum sulfate hydrate, aluminum chloride, aluminum chloride hydrate, aluminum bromide, aluminum iodide, and aluminum fluoride, aluminum alkoxides such as aluminum tri-sec-butoxide, aluminum trimethoxide, aluminum triethoxide, aluminum tri-n-propoxide, aluminum triisopropoxide,” paragraph 59);
b) adding particles of cathode active material to the mixture, wherein the cathode active material is selected from a group consisting of lithium- and manganese- rich (LMR), lithium iron phosphate (LFP), lithium manganese iron phosphate (LMFP), lithium nickel cobalt manganese aluminum (NCMA), lithium nickel manganese cobalt (NMC), lithium nickel oxide (LNO), lithium manganese oxide (LMO), and combinations thereof (“The precursor solution according to the present disclosure contains the organic solvent, the lithium oxoacid salt, and the aluminum compound as described above, but may further contain particles of an active material such as a positive electrode active material,” paragraph 64; “As the positive electrode active material, for example, a lithium composite oxide,” paragraph 66; “Examples of such a composite oxide include LiCoO2, LiNiO2, LiMn2O4, Li2Mn2O3, LiCr0.5Mn0.5O2, LiFePO4,” paragraph 66);
c) heating the mixture in the absence of water and alcohol (as noted above, paragraph 42 teaches that toluene can be the only solvent used; “when water is used in place of an organic solvent, elements constituting active material particles are dissolved in water, and an active material coated with a desired LiAl composite oxide cannot be obtained,” paragraph 36, indicating that Yamamoto explicitly teaches that water be absent in the mixture) to a first predetermined temperature in a range from 80 °C to 250 °C for a first predetermined period to form a metal oxide coating on the particles of the cathode active material (“the heating temperature in the heat treatment is preferably 50 °C. or higher and 250 °C. or lower, more preferably 60 °C. or higher and 230 °C. or lower, and further more preferably 80 °C. or higher and 200 °C. or lower,” paragraph 112; “the heating time in the heat treatment is preferably 10 minutes or more and 180 minutes or less, and more preferably 20 minutes or more and 120 minutes or less,” paragraph 113, indicating this first heating step is for a predetermined time period); and
e) calcining the particles of the cathode active material at a second predetermined temperature in a range from 300 °C to 550 °C for a second predetermined period (“The heating temperature in this step is preferably 300 °C. or higher and 600 °C. or lower, more preferably 330 °C. or higher and 570 °C. or lower, and further more preferably 350 °C. or higher and 570 °C. or lower,” paragraph 128; “the heating time in this step is preferably 5 minutes or more and 240 minutes or less, more preferably 10 minutes or more and 180 minutes or less, and further more preferably 15 minutes or more and 120 minutes or less,” paragraph 129, indicating this second heating step is for a predetermined time period).
Yamamoto does not explicitly teach filtering the particles of the cathode active material from the mixture. However, Ruan teaches filtering after stirring (“and after stirring, filtration or evaporation,” paragraph 10). Additionally, Yamamoto acknowledges that the heating step may not remove all of the solvent, but the rest can be removed at a later step (“Even if not all the organic solvent is removed in this step, the remaining organic solvent can be sufficiently removed in a later step,” paragraph 109); step d taught by Ruan viably serves as that general later step taught by Yamamoto.
It would have been obvious to a person having ordinary skill in the art before the effective filing date of the invention to take the method taught by Yamamoto and include step d to filter the particles after heating and stirring, as taught by Ruan, in order to fully ensure that the particles are separated from any remaining organic solvent, as Yamamoto teaches.
Regarding Claim 16, Yamamoto modified by Ruan teaches the method of claim 15, wherein Yamamoto teaches the one or more organic isopropoxide precursors comprise aluminum (Al) and titanium (Ti) (“Such an aluminum compound may be any as long as it shows solubility in the organic solvent constituting the precursor solution, and examples thereof include metal salt compounds such as aluminum nitrate, aluminum nitrate hydrate, aluminum orthophosphate, aluminum sulfate, aluminum sulfate hydrate, aluminum chloride, aluminum chloride hydrate, aluminum bromide, aluminum iodide, and aluminum fluoride, aluminum alkoxides such as aluminum tri-sec-butoxide, aluminum trimethoxide, aluminum triethoxide, aluminum tri-n-propoxide, aluminum triisopropoxide,” paragraph 59). Yamamoto teaches a metal oxide coating comprising multiple metals, but not that one of the metals is titanium. However, Ruan further teaches a metal oxide coating comprising aluminum and titanium, using organic isopropoxide precursors of each (“a first metal oxide layer with MeOx on the surface of the cathode material,” paragraph 11; “Me includes at least one of Al, Mg, Ti and Zr,” paragraph 10; “Metal alkoxide sols are sols formed during stirring using at least one of tetrabutyl titanate, titanium isopropoxide, TiCl-NER8-, aluminum isopropoxide, aluminum nitrate, aluminum phosphate, zirconium acetate, and magnesium acetate as coating materials,” paragraph 13). Ruan teaches the benefit of a composite metal oxide coating with aluminum and titanium improves cycling and is suitable for high-voltage [“the surface ceramic oxide layer effectively inhibits HF corrosion, metal ion dissolution, and the release of active oxygen. The lithium-ion secondary battery prepared using this method is suitable for high-voltage charge-discharge (≥4.30 V), exhibits high energy density, good cycle life and safety performance, and significantly improved high-temperature storage performance” paragraph 6]. Ruan specifically notes that titanium is preferable over other metals as a composite with aluminum [“a layer of Al and Sn or Al and Co composite oxide can suppress the capacity decline to the maximum extent due to the introduction of active materials (Co and Sn). However, this coating has a significant drawback: Co is exposed on the surface and is easy to dissolve, causing a decline in cycle performance,” paragraph 4].
It would have been obvious to a person having ordinary skill in the art before the effective filing date of the invention to take the method taught by Yamamoto and modified by Ruan and further modify to add titanium isopropoxide to the precursor solution to form a metal oxide coating that comprises aluminum and titanium in order to further improve cycle life and safety performance, as taught by Ruan.
Regarding Claim 17, Yamamoto modified by Ruan teaches the method of claim 15, wherein Yamamoto further teaches the first metal oxide coating on the particles of the cathode active material have a thickness in a range from 2nm to 50 nm (“the average thickness of the coating layer constituted by the material containing the precursor of the LiAl composite oxide is preferably 2 nm or more and 300 nm or less, more preferably 3 nm or more and 150 nm or less, and further more preferably 4 nm or more and 80 nm or less,” paragraph 95). Please see MPEP § 2144.05(I): In the case where the claimed ranges "overlap or lie inside ranges disclosed by the prior art" a prima facie case of obviousness exists.
Regarding Claim 18, Yamamoto modified by Ruan teaches the method of claim 15, wherein the first metal oxide coating on the particles of the cathode active material have a thickness in a range from 5nm to 20 nm (“the average thickness of the coating layer constituted by the material containing the precursor of the LiAl composite oxide is preferably 2 nm or more and 300 nm or less, more preferably 3 nm or more and 150 nm or less, and further more preferably 4 nm or more and 80 nm or less,” paragraph 95). Please see MPEP § 2144.05(I): In the case where the claimed ranges "overlap or lie inside ranges disclosed by the prior art" a prima facie case of obviousness exists.
Regarding Claim 19, Yamamoto modified by Ruan teaches the method of claim 1, wherein Yamamoto further teaches the first solvent is not alcohol (“the organic solvent constituting the precursor solution according to the present disclosure is preferably an organic solvent that is nonaqueous and contains one type or two or more types selected from the group consisting of n-butyl alcohol, ethylene glycol monobutyl ether, butylene glycol, hexylene glycol, pentanediol, hexanediol, heptanediol, toluene, o-xylene, p-xylene, hexane, heptane, and octane,” paragraph 42) and the heating and stirring of the mixture to the first predetermined temperature occurs in the absence of water and alcohol (as noted above, paragraph 42 teaches that toluene or other non-alcohol solvents from the list can be the solvent used; “when water is used in place of an organic solvent, elements constituting active material particles are dissolved in water, and an active material coated with a desired LiAl composite oxide cannot be obtained,” paragraph 36, indicating that Yamamoto explicitly teaches that water be absent in the mixture).
Regarding Claim 20, Yamamoto modified by Ruan teaches the method of claim 19, wherein Yamamoto further teaches the first solvent is toluene (“the organic solvent constituting the precursor solution according to the present disclosure is preferably an organic solvent that is nonaqueous and contains one type or two or more types selected from the group consisting of n-butyl alcohol, ethylene glycol monobutyl ether, butylene glycol, hexylene glycol, pentanediol, hexanediol, heptanediol, toluene, o-xylene, p-xylene, hexane, heptane, and octane,” paragraph 42).
Claim 6 is rejected under 35 U.S.C. 103 as being unpatentable over Yamamoto in view of Ruan and in further view of Yokoyama et al. (US-20210135203-A1) hereafter referred to as Yokoyama.
Regarding Claim 6, Yamamoto modified by Ruan teaches the method of claim 1, wherein the first metal oxide coating on the particles of the cathode active material include an N-metal oxide coating, where N is an integer greater than one (“a surface of an active material can be favorably coated with a coating material constituted by a LiAl composite oxide,” paragraph 34). However, Yamamoto does not teach that the one or more first organic isopropoxide precursors include N organic isopropoxide precursors, since Yamamoto uses lithium oxoacid salt instead of a lithium isopropoxide.
However, Yokoyama teaches forming a metal oxide coating on cathode electrode active material, where one of the metal oxide contains lithium (“the coating layer P12 can be made composed of a lithium-containing multiple oxide,” paragraph 90; P11 and P12 in Fig. 2). Therein, Yokoyama teaches that lithium isopropoxide precursor is one of many compounds that could be used to ultimately form such a metal oxide coating (“Examples of the lithium compound contained in the coating layer P12 include inorganic salts such as LiH, LiF, LiCl, LiBr, LiI, LiClO, LiClO4, LiNO3, LiNO2, Li3N, LiN3, LiNH2, Li2SO4, Li2S, LiOH, and Li2CO3, carboxylates such as lithium formate, lithium acetate, lithium propionate, lithium 2-ethylhexanoate, and lithium stearate, hydroxy acid salts such as lithium lactate, lithium malate, and lithium citrate, dicarboxylates such as lithium oxalate, lithium malonate, and lithium maleate, alkoxides such as lithium methoxide, lithium ethoxide, and lithium isopropoxide,” paragraph 91). Separately, Ruan also teaches the general approach of forming a metal oxide coating containing more than one metal using more than one organic isopropoxide precursor (“Metal alkoxide sols are sols formed during stirring using at least one of tetrabutyl titanate, titanium isopropoxide, TiCl-NER8-, aluminum isopropoxide, aluminum nitrate, aluminum phosphate, zirconium acetate, and magnesium acetate as coating materials,” paragraph 13; note that Ruan teaches more than one metal alkoxide can be used among a list that includes multiple organic isopropoxide precursors that will lead to an N-metal oxide coating, where N is an integer greater than one).
It would have been obvious to a person having ordinary skill in the art before the effective filing date of the invention to take the method taught by Yamamoto and modified by Ruan and further modify it to use a lithium isopropoxide instead of lithium oxoacid salt to form the N-metal oxide coating where N is greater than 1, as taught by Yokoyama, a strategy reinforced by Ruan. Please see MPEP § 2144.07.
Claims 9 and 10 are rejected under 35 U.S.C. 103 as being unpatentable over Yamamoto in view of Ruan, and in further view of Honda et al. (US-20160336593-A1), hereafter referred to simply as Honda.
Regarding Claim 9, Yamamoto modified by Ruan teaches the method of claim 1, but Yamamoto does not teach additional steps in Claim 9 to result in a second metal oxide coating. However, Ruan teaches a method for forming a metal oxide layer on cathode electrode active material using organic isopropoxide precursors, wherein the process is repeated by adding cathode active material particles that have already been coated in a first metal oxide layer in order to create a second metal oxide layer (“the cathode material coated with the first metal oxide layer is added again to an organic solution containing metal alkoxide,” paragraph 11). Applying this principle to Yamamoto modified by Ruan, the following Claim 9 limitations are met, where the method of Claim 1 further comprises after d) and before e):
g) creating a mixture by adding one or more second organic isopropoxide precursors to a second solvent, wherein the second solvent is not alcohol (“the organic solvent constituting the precursor solution according to the present disclosure is preferably an organic solvent that is nonaqueous and contains one type or two or more types selected from the group consisting of n-butyl alcohol, ethylene glycol monobutyl ether, butylene glycol, hexylene glycol, pentanediol, hexanediol, heptanediol, toluene, o-xylene, p-xylene, hexane, heptane, and octane,” paragraph 42 of Yamamoto);
h) stirring the mixture until the one or more second organic isopropoxide precursors dissolve (“The organic solvent may be any as long as it exhibits a function of dissolving a lithium oxoacid salt and an aluminum compound,” paragraph 41 of Yamamoto; “the reagent bottle was placed on a magnetic stirrer, and aluminum nitrate nonahydrate was completely dissolved in 2-n-butoxyethanol while stirring at room temperature,” paragraph 233 of Yamamoto, is just a specific example preparation in Yamamoto which makes explicit that the aluminum compound, which can be aluminum isopropoxide, is stirred in the organic solvent, which can be toluene, until it completely dissolves in the solution);
i) adding the particles of the cathode active material including the first metal oxide coating to the mixture (“The precursor solution according to the present disclosure contains the organic solvent, the lithium oxoacid salt, and the aluminum compound as described above, but may further contain particles of an active material such as a positive electrode active material,” paragraph 64 of Yamamoto; ““the cathode material coated with the first metal oxide layer is added again to an organic solution containing metal alkoxide,” paragraph 11 of Ruan, again showing that Ruan teaches that the positive electrode active material disclosed by Yamamoto could be coated in a first metal oxide layer)
j) heating the mixture to the first predetermined temperature for the first predetermined period to form a second metal oxide coating on the particles of the cathode active material (“the heating temperature in the heat treatment is preferably 50 °C. or higher and 250 °C. or lower, more preferably 60 °C. or higher and 230 °C. or lower, and further more preferably 80 °C. or higher and 200 °C. or lower,” paragraph 112; “the heating time in the heat treatment is preferably 10 minutes or more and 180 minutes or less, and more preferably 20 minutes or more and 120 minutes or less,” paragraph 113, indicating this first heating step is for a predetermined time period); and
k) filtering the particles of the cathode active material from the mixture (“the mixture is filtered, evaporated to dryness, and then heat-treated to obtain a second metal oxide layer,” paragraph 31 of Ruan, with this excerpt chosen to show that Yamamoto modified by Ruan would teach filtration as part of obtaining the second metal oxide layer in addition to the first). Ruan teaches the benefit of multiple layers is improving first-cycle efficiency of the material (“The beneficial effects of the present invention are as follows: the surface of the positive electrode material layer of the present invention is coated with a first metal oxide layer and a second metal oxide layer,” paragraph 19; “This structure can improve the first-cycle efficiency of the material,” paragraph 19).
It would have been obvious to a person having ordinary skill in the art before the effective filing date of the invention to take the method taught by Yamamoto and modified by Ruan and further modify the method to apply an additional metal oxide coating from one of the metal oxides taught by Ruan in order to further improve the first-cycle efficiency of the material, as taught by Ruan.
Additionally, neither Yamamoto nor Ruan teach step f) rinsing the particles of the cathode active material including the first metal oxide coating. However, Honda teaches a method for coating cathode active material with a metal oxide layer using an organic isopropoxide precursor, wherein the particles are rinsed after filtering, step d, (“the precipitate was filtered by suction, further washed with water sufficiently,” paragraph 211). Rinsing particles in a chemical manufacturing process generally has the benefit of removing excess and/or undesired substances preceding the next step in a chemical process.
It would have been obvious to a person having ordinary skill in the art before the effective filing date of the invention to take the process taught by Yamamoto and modified by Ruan and further modify to rinse the particles after filtration, as taught by Honda, to remove undesired substances from the particles before proceeding to the next step.
Regarding Claim 10, Yamamoto modified by Ruan teach the method of claim 1, where Ruan further teaches drying the particles of the cathode active material after d) and before e) (“The mixture was then filtered, dried, and heated to 500 °C to obtain a TiO2-coated ternary lithium nickel cobalt manganese,” paragraph 27). Neither Yamamoto nor Ruan explicitly teach washing the particles of the cathode active material after d) and before e).
However, Honda teaches a method for coating cathode active material with a metal oxide layer using an organic isopropoxide precursor, wherein the particles are rinsed after filtering, step d, (“the precipitate was filtered by suction, further washed with water sufficiently,” paragraph 211). Rinsing particles in a chemical manufacturing process generally has the benefit of removing undesired substances preceding the next step in a chemical process.
It would have been obvious to a person having ordinary skill in the art before the effective filing date of the invention to take the process taught by Yamamoto and modified by Ruan and further modify to rinse the particles after filtration, as taught by Honda, to remove undesired substances from the particles before proceeding to the next step.
Claim 12 is rejected under 35 U.S.C. 103 as being unpatentable over Yamamoto in view of Ruan, and in further view of Xing et al. (CN 114784265 A, see machine translation previously provide), hereafter referred to simply as Xing.
Regarding Claim 12, Yamamoto modified by Ruan teaches the method of claim 1, but does not further teach the first metal oxide coating includes a dual metal oxide selected from a group consisting of Li-Ce, Li-Zr, Ce-Al, Gd-Al, Gd-Ce, Sb-Al, Sb-Ce, Ge-Al, and Ge-Ce. Instead, Yamamoto teaches the first metal oxide coating is Li-Al (“coating layer constituted by an α-phase lithium aluminate compound represented by LiAlO2 was obtained,” paragraph 268).
However, Xing teaches a process for coating cathode active material with a metal oxide coating that includes a dual metal oxide selected from a group consisting of Li-Ce, Li-Zr, Ce-Al, Gd-Al, Gd-Ce, Sb-Al, Sb-Ce, Ge-Al, and Ge-Ce (“high-nickel single-crystal lithium nickel cobalt manganese oxide cathode material includes a substrate and a lithium-containing coating layer,” paragraph 6; “the lithium-containing coating layer is one or more of Li3NbO4, LiNbO3, Li2ZrO3, or LiAlO2,” paragraph 7). Xing teaches that such a dual-metal oxide coating layer can help “improve initial charge/discharge capacity and rate performance,” paragraph 4. Xing teaches these benefits are borne from either dual metal oxides, Li2ZrO3 or LiAlO2, establishing these are equivalents known for the same purpose.
It would have been obvious to a person having ordinary skill in the art before the effective filing date of the invention to take the process taught by Yamamoto and modified by Ruan and further modify to substitute the dual metal oxide coating taught by Yamamoto (Li-Al) with another taught by Xing (Li-Zr). Please see MPEP § 2144.08(II).
Claim 13 is rejected under 35 U.S.C. 103 as being unpatentable over Yamamoto in view of Ruan, and in further view of Honda, as evidenced by GORGEOUS Ceramics (“Aluminum Oxide vs. Zirconia: Comprehensive Comparison Guide”), hereafter referred to simply as GORGEOUS Ceramics.
Regarding Claim 13, Yamamoto modified by Ruan and Honda teaches the method of claim 9, wherein Ruan further teaches a metal oxide in the first metal oxide coating is less conductive than a metal oxide in the second metal oxide coating (“a cathode material with a first metal oxide layer 2 of Al2O3 and a second metal oxide layer 3 of ZrO2 is obtained,” paragraph 45). GORGEOUS Ceramics states that alumina (Al2O3) has a resistivity of >10¹⁴ Ω·cm, and zirconia (ZrO2) has a resistivity of >10¹⁰ Ω·cm (see table under sub-heading “Core performance comparison”). The property of resistivity is inversely correlated with conductivity, so the metal oxide in the first metal oxide layer taught by Ruan, Al2O3, is less conductive than the metal oxide in the second metal oxide layer, ZrO2.
Yamamoto teaches that the first metal oxide coating comprises both lithium and aluminum, rather than just aluminum. However, as stated previously, it would have been obvious to a person having ordinary skill in the art before the effective filing date of the invention to take the method taught by Yamamoto and modified by Ruan and further modify the method to simply exclude the lithium oxoacid salt when forming the first metal oxide coating in order to form a metal oxide coating from just aluminum isopropoxide, as taught by Ruan, in order to reduce costs and simplify the method while still applying a first metal oxide coating to the active material.
Claim 14 is rejected under 35 U.S.C. 103 as being unpatentable over Yamamoto in view of Ruan, and in further view of Honda and Lee et al. (US-20150228975-A1), hereafter referred to simply as Lee.
Regarding Claim 14, Yamamoto modified by Ruan and Honda teach the method of claim 9, wherein Ruan and Yamamoto both further teach that the first metal oxide in the first metal oxide coating is selected from a group consisting of Ce, Al, and Zr (“a cathode material with a first metal oxide layer 2 of Al2O3,” paragraph 45 of Ruan; “coating layer constituted by an α-phase lithium aluminate compound represented by LiAlO2 was obtained,” paragraph 268 of Yamamoto). Ruan does not teach that a metal oxide in the second metal oxide coating is selected from a group consisting of Li, Gd, Sb, and Ge.
However, Lee teaches a method for coating cathode active material with at least two metal oxide layers. Specifically, Lee teaches first metal oxide in the first metal oxide coating is selected from a group consisting of Ce, Al, and Zr (“the metal oxide layer coated on the surface of the cathode active material after the performing of the heat treatment (the fourth step) may include an oxide layer of at least one metal selected from the group consisting of Mg, Ca, Sr, Ba, Y, Ti, Zr, V, Nb, Ta, Cr, Mo, W, Mn, Fe, Co, Ir, Ni, Zn, Al, Ga, In, Si, Ge, Sn, La, and Ce,” paragraph 60) and a second metal oxide in the second metal oxide coating is selected from a group consisting of Li, Gd, Sb, and Ge (“the metal oxide layer coated on the surface of the cathode active material after the performing of the heat treatment (the fourth step) may include an oxide layer of at least one metal selected from the group consisting of Mg, Ca, Sr, Ba, Y, Ti, Zr, V, Nb, Ta, Cr, Mo, W, Mn, Fe, Co, Ir, Ni, Zn, Al, Ga, In, Si, Ge, Sn, La, and Ce,” paragraph 60). Lee specifies that the metal oxide layers selected from the group of elements listed above can be “a multilayer structure having two or more layers in which each of two or more metal composite oxides is sequentially stacked,” paragraph 29. Lee states the benefit of coating the cathode active material with two or more of these metal oxides is to “improve thermal stability and cycle characteristics,” paragraph 21.
It would have been obvious to a person having ordinary skill in the art before the effective filing date of the invention to take the process taught by Yamamoto, further modified by Ruan and Honda, and expand the list of metal oxides taught in Ruan to include germanium (Ge) as taught by Lee for the second metal oxide layer. Doing so, as Lee teaches, provides an additional metal oxide option that can improve thermal stability and cycle characteristics of the resulting cathode.
Response to Arguments
Applicant's arguments filed 8/25/2026 have been fully considered, and the following argument was considered persuasive: “the coatings of the applied references form at different points in the process compared to the present disclosure. In Ruan, the metal oxide layer does not form during stirring. It forms during the subsequent evaporation and high-temperature sintering: "heat-treating the positive electrode material coated with the metal hydroxide layer to form a first metal oxide layer having MeOx" (paragraph 11); "sintering process is to heat to 450-800°C" (paragraph 15).” The examiner found this persuasive because the examiner agrees that Ruan explicitly states that the metal oxide layer forms at a step in the process different from that in the instant application’s Claim 1.
All other arguments are moot, as the examiner has issued a new basis for rejection for all claims. Because the new basis for rejection is being applied to original claims, this action is non-final.
Correspondence
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/JORDAN P WILKERSON/Examiner, Art Unit 1783
/MARIA V EWALD/Supervisory Patent Examiner, Art Unit 1783
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