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
Claims 1-2, 4-10 are pending in the application. The amendment filed November 11, 2025 has been entered but does not place the application in condition for allowance.
Applicant’s amendments, filed November 11, 2025, overcome the original 35 U.S.C. 103 rejections over the prior art. New rejections follow.
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.
This application currently names joint inventors. In considering patentability of the claims the examiner presumes that the subject matter of the various claims was commonly owned as of the effective filing date of the claimed invention(s) absent any evidence to the contrary. Applicant is advised of the obligation under 37 CFR 1.56 to point out the inventor and effective filing dates of each claim that was not commonly owned as of the effective filing date of the later invention in order for the examiner to consider the applicability of 35 U.S.C. 102(b)(2)(C) for any potential 35 U.S.C. 102(a)(2) prior art against the later invention.
Claims 1-2, 4-8, 10 are rejected under 35 U.S.C. 103 as being unpatentable over Yang et al (US 20120288617 A1) as applied in view of Cho et al (US 6083643) and Wu et al (US 8722004 B2).
Support is provided by evidentiary reference “Chelating Agent,” Encyclopedia and Handbook of Materials, Parts, and Finishes 3rd Ed., Taylor & Francis, p167.
Regarding claim 1, Yang teaches a method of preparing an electrode active material for a lithium secondary battery (Abstract), the method comprising heating a mixed solution to combust the mixed solution into a powder (Abstract, [0019]), wherein the mixed solution includes additives, a metal raw material, and water (Abstract, [0013],[0016]), wherein the metal raw material includes a lithium raw material, a nickel raw material, a cobalt raw material, and a manganese raw material ([0016]).
Yang additionally teaches one or more of the additives may be water miscible and may be a carbon-containing species or an organic material that promotes synthesis of the battery active materials from the dissolved metal ions, for example, by combustion, and also teaches that one or more additives may facilitate formation of high quality active materials by forming complexes with the ions ([0013]). The additives participate in reactions within the mixed solutions and read on the limitation of fuel components. Yang discloses examples of carbon-containing species as sugars such as sucrose ([0018], [0024]) (a second fuel) and nitrogen containing species of organic material that promote combustion as urea and glycine ([0022]) (embodiments of a first fuel). While teaching an embodiment of the mixed solution ([0016]), Yang states that adjusting the composition of the cathode material entails balancing various battery properties that are influenced by metal composition, and also teaches in [0028] that their process can yield a battery active material suitable for a lithium ion cathode electrode, further reading upon the claimed limitation of preparing a positive electrode active material for a lithium secondary battery.
Yang does not disclose heat treating the powder formed from the combustion process or the weight ratio of the first fuel to the second fuel.
Cho is relied upon to teach heat treating powder formed by solution combustion of a mixed solution of metal raw materials and a fuel as part of a method to prepare cathode active material for a lithium ion battery (Col 3: lines 53-62). Specifically, Cho reveals that “the process further comprises the steps of sintering the powder at about 700 to about 850°C for about 4-6 hours” (Col 3: lines 63-65). Cho further teaches that the sintering process produces a cathode active material with a capacity over 125 mAh/g (Col 4: lines 30-31, 59-61). It would have been obvious to one of ordinary skill in the art at the time the invention was filed to have modified the method of Yang to include a step to heat treat the powder formed by combustion of the mixed solution, as taught by Cho, in order to produce a cathode active material with a capacity over 125 mAh/g.
Wu teaches preparation of a lithium electrode material via a similar solution-combustion method followed by further heat treatment of the powder formed from the combustion process (Wu: Abstract; Yang’s lithium electrode materials: [0029]). Wu teaches a first fuel such as urea and glycine (Col 4 lines 10-19) and a carbon source as a second fuel, such as glucose or sucrose (Col 3 lines 63-67, Col 4 lines 1-9). Wu further discloses that the first fuel can be added at 20-250% according to the weight of the final product (Col 4: lines 16-19) and that the second fuel can be added at a ratio of 10-200% according to the weight of the final product (Col 4: lines 1-9). Wu teaches their method allows for a self-propagating combustion synthesis that is very fast usually in several minutes for the reaction to complete, resulting in a fast production rate (Col 4: lines 28-31; Col 7 lines 10-17). A person of ordinary skill in the art would have been motivated to modify modified Yang’s solution combustion process to apply the relative amounts of the first fuel and second fuel as taught by Wu to take advantage of a self-propagating combustion synthesis that is very fast usually in several minutes for the reaction to complete, thereby enabling a fast production rate. Consequently, within the combination, a ratio of the first fuel to the second fuel is (20-250% of weight of final product)/(10-200% weight of final product), and corresponds to a range of 20/200 - 250/10, or 0.1 - 25, which overlaps with the claimed range. Overlapping ranges provides a prima facie case of obviousness; see MPEP 2144.05, I.
Regarding claim 2, the combination above teaches the method of claim 1, and the combination teaches the first fuel is urea (Yang: [0022]).
Yang does not teach the second fuel is citric acid.
Yang does teach the mixed solution may comprise one or more of the additives that is water miscible, is a carbon-containing species or an organic material that promotes synthesis of the battery active materials from the dissolved metal ions, or that facilitates formation of high quality active materials by forming complexes with the ions ([0013]). Cho teaches use of citric acid as a chelating agent within their mixed solution (Col 4: lines 6-7). It is known to one of ordinary skill in the art that a chelating agent forms complexes with metal ions (p167 of Encyclopedia and Handbook of Materials, Parts, and Finishes 3rd Ed.) and that citric acid is water miscible and carbon-containing; therefore, addition of Cho’s chelating agent satisfies functions for additives taught by Yang and is expected to work within Yang’s method. Cho explains that use of the citric acid as a chelating agent reduces the process time for preparing a cathode active material for a lithium ion battery, and results in a stable deposit phase at a low temperature compared to an alternative solid phase reaction method (Col 2: lines 58-64; Col 4: lines 54-58; Col 7: lines 18-27). It would have been obvious to a person of ordinary skill in the art at the time the invention was filed to have modified the modified method of Yang to use citric acid as a chelating agent as taught by Cho in order to reduce the process time for preparing a cathode active material for a lithium ion battery, and to obtain a stable deposit phase at a low temperature. Citric acid as a chelating agent would participate in reactions with metal ions present in the mixed solution, and accordingly would read on an embodiment of a second fuel.
Regarding claim 4, the combination above teaches the method of claim 1, and as pointed out previously in addressing the limitations of claim 1, Wu teaches a ratio of the first fuel to the second fuel is (20-250% of weight of final product)/(10-200% weight of final product), and which results in a range of 20/200 - 250/10, or 0.1 - 25, which overlaps with the claimed range. Overlapping ranges provides a prima facie case of obviousness; see MPEP 2144.05, I.
Regarding claim 5, the combination above teaches the method of claim 1. Yang further teaches that the fuel content of the mixture is between 0.1% and about 20% by weight, presumably based on the mixed solution which includes fuel additives, a metal raw material, and water (Abstract, [0025], [0013]). Within the combined prior art, the fuel content of the mixture would be a total amount of the first fuel and the second fuel. Accordingly, a total amount of the first fuel and the second fuel based on a total amount of the metal raw material, which is a subset of the mixture and therefore comprising a lesser weight than the total mixture, would be greater than 0.1% and 20% by weight, which overlaps with the claimed range. In the case where the claimed ranges "overlap or lie inside ranges disclosed by the prior art" a prima facie case of obviousness exists. In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976); In re Woodruff, 919 F.2d 1575, 16 USPQ2d 1934 (Fed. Cir. 1990); see MPEP 2144.05, I.
Regarding claim 6, the combination above teaches the method of claim 1. As pointed out previously in addressing the limitations of claim 1, Yang teaches a method of preparing an electrode active material for a lithium secondary battery wherein a mixed solution is heated to combust the mixed solution into a powder (Abstract, [0019]), and discloses that an exothermic reaction, or heating process, may be performed.
However, Yang is silent regarding temperatures used for the process.
Cho teaches that the combustion of the mixed solution to form a battery active material powder may occur at about 300-400°C (Col 3: lines 53-62) and that their process using citric acid as an additive within their mixed solution enables a stable deposit phase at a low temperature, which is preferred over the high temperature of alternative methods of active material synthesis (Col 2: lines 32-34; Col 4: lines 54-57). It would have been obvious to one of ordinary skill in the art at the time the invention was filed to have modified the modified method of Yang to use citric acid as an additive in the mixed solution and lower temperatures 300-400°C for heating the mixed solution, as taught by Cho, to form a stable deposit phase in the formation of battery active material powder at lower temperatures.
Regarding claim 7, the combination above teaches the method of claim 1, and as pointed out previously in addressing the limitations of claim 1, Cho teaches the powder is heat treated at a temperature of 700 to about 850°C (Col 3: lines 63-65), which is within the claimed range. In the case where the claimed ranges "overlap or lie inside ranges disclosed by the prior art" a prima facie case of obviousness exists. In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976); In re Woodruff, 919 F.2d 1575, 16 USPQ2d 1934 (Fed. Cir. 1990); see MPEP 2144.05, I.
Regarding claim 8, the combination above teaches the method of claim 1, and Yang states that that the method can yield a battery active material suitable for a lithium ion cathode electrode ([0028]). The combined prior art therefore reads upon the claimed limitation that a positive electrode active material for a lithium secondary battery can be prepared by the method of claim 1.
Regarding claim 10, the combination above teaches the positive electrode active material of claim 8. Yang further teaches a positive electrode using the positive electrode active material ([0028]), a negative electrode ([0005]), and a separator disposed between the positive electrode and the negative electrode and an electrolyte ([0006], [0015]).
Claim 9 is rejected under 35 U.S.C. 103 as being unpatentable over Yang et al (US 20120288617 A1) in view of Cho et al (US 6083643) and Wu et al (US 8722004 B2), as applied to claim 8 above, and further in view of Hoog (TW 201318256 A).
Regarding claim 9, the combination above teaches the positive electrode active material of claim 8.
However, the combination is silent with regards to the positive electrode active material comprising single particles having the claimed average particle diameter.
Hoog teaches positive electrode active materials prepared from similar combustion synthesis of a precursor solution of metal ions in a solvent ([0010]-[0011]; Fig. 1), and further teaches the resulting powder has the benefit of being made of particles of similar size and substantially free of agglomeration and is described as a monomorphic powder ([0059]), which reads on form as single particles. In addition, Hoog discloses the average diameter of the microparticles is typically less than about 50 μm, such as between about 0.1 μm and about 20 μm ([0059]), which overlaps with the claimed range. In the case where the claimed ranges "overlap or lie inside ranges disclosed by the prior art" a prima facie case of obviousness exists. In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976); In re Woodruff, 919 F.2d 1575, 16 USPQ2d 1934 (Fed. Cir. 1990); see MPEP 2144.05, I. Therefore, the combined art supports a case of prima facie case of obviousness. Hoog also teaches these materials have advantages in battery applications because they can be packaged more densely than other powders ([0059]). It would have been obvious to one of ordinary skill in the art at the time the invention was filed to have modified the modified method of Yang to use particles having the average particle diameter taught by Hoog for the benefit of more tightly packaging the powders.
Response to Arguments
Applicant’s arguments, filed November 11, 2025, with respect to prior art rejections of the limitation “wherein a weight ratio of the first fuel to the second fuel is in a range of 60:40 to 90:10” as originally recited in original claim 3, and consequently, incorporated into amended claim 1, have been fully considered and are persuasive.
Accordingly, the 35 U.S.C. 103 rejections of original claims 3-4 over Cho et al in view of Yang et al and evidentiary reference “Chelating Agent”, and further in view of Zhuravlev et al “Solution Combustion Synthesis of Lithium Cobalt Oxide-Cathode Material for Lithium-Ion Batteries,” Int. J. Electrochem. Sci., 14 (2019) 2965 – 2983, and the 35 U.S.C. 103 rejections of original claims 3-4 over Yang et al in view of Cho et al and evidentiary reference “Chelating Agent,” and further in view of Zhuravlev et al “Solution Combustion Synthesis of Lithium Cobalt Oxide-Cathode Material for Lithium-Ion Batteries,” Int. J. Electrochem. Sci., 14 (2019) 2965 – 2983 have been withdrawn.
Conclusion
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/G.L.L./Examiner, Art Unit 1726
/BACH T DINH/Primary Examiner, Art Unit 1726 02/12/2026