DETAILED ACTION
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 . If status of the application as subject to 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 a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
Continued Examination Under 37 CFR 1.114
A request for continued examination under 37 CFR 1.114, including the fee set forth in 37 CFR 1.17(e), was filed in this application after final rejection. Since this application is eligible for continued examination under 37 CFR 1.114, and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114. Applicant's submission filed on 12/15/2025 has been entered.
Status of Claims
Claims 1-16 were rejected in the office action mailed 9/16/2025. Applicant cancelled claims 11-12. Claims 1-10 & 13-16 are pending in the application and are presently examined.
Response to Amendment / Arguments
The amendment filed 12/15/2025, in response to the office action mailed 9/16/2025, has been entered. Applicant’s arguments and claim amendments overcame all objections and 35 U.S.C. 103 rejections; nevertheless, the claims remain rejected under 35 U.S.C. 103 due to additional prior art.
Claims 1 & 6 were rejected, in the 9/16/2025 office action, under 35 U.S.C. 103 as being unpatentable over US20210408528A1 (Chae) in view of US20190248673A1 (Kaneda), US20100068624A1 (Hiratsuka), and US20210126256A1 (Shin). Claims 1 & 6 are now rejected under 35 U.S.C. 103 as being unpatentable over US20210135215A1 (Kil), US20200014023A1 (Ko), US20190248673A1 (Kaneda), and US20100068624A1 (Hiratsuka).
Hiratsuka is used in both office actions. Hiratsuka describes a positive electrode active material with 1-5 μm particle size and 10-30 mL/100g dibutyl phthalate (DBP) absorption (abstract; paragraph 12). In the 9/16/2025 office action, Hiratsuka was used to show obviousness of the claimed 14-22 mL/100g DBP value, of the second lithium composite oxide particles.
Applicant argued persuasively that the claimed second lithium composite oxide particles have 0.1-0.3 μm primary particle size, and that if this size range was applied to Hiratsuka, then Hiratsuka’s DBP value would also change. Also, Applicant argued persuasively that Hiratsuka argued against a primary particle size less than 1 μm (paragraph 22).
In this office action, Hiratsuka is not used to show obviousness of the DBP value of the second lithium composite oxide particles. In this office action, Hiratsuka is used to show obviousness of the DBP value of the claimed first lithium composite oxide particles, which have 1.4 μm to 2.5 μm primary particle size. This claimed primary particle size overlaps Hiratsuka’s 1 μm to 5 μm particle size, and is not inconsistent with Hiratsuka’s teaching against primary particles that are smaller than 1 μm.
Regarding claims 13-16, Applicant argued, with no details, that “the Office failed to apply Kawakita in a manner sufficient to cure the deficiencies of Chae”. Examiner reviewed the rejection of claims 13-16, based on Kawakita, and it looks like a correct rejection.
Claim Rejections - 35 USC § 103
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:
Determining the scope and contents of the prior art.
Ascertaining the differences between the prior art and the claims at issue.
Resolving the level of ordinary skill in the pertinent art.
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.
The claims are in bold font, the prior art is in parentheses.
Claims 1- are rejected under 35 U.S.C. 103 as being unpatentable over US20210135215A1 (Kil), US20200014023A1 (Ko), US20190248673A1 (Kaneda), and US20100068624A1 (Hiratsuka), together “modified Kil”.
With regard to claims 1 & 6, Kil teaches the following claim limitations (reordered to place limitations for each particle type together):
Claim 6 only
A nonaqueous electrolyte secondary battery comprising: a positive electrode; a negative electrode; and a nonaqueous electrolyte, wherein the positive electrode includes the positive electrode active material (abstract; paragraphs 8, 23, & 145-146)
Claim 1
A positive electrode active material (paragraph 8: positive active material) comprising:
Claims 1 & 6
first lithium composite oxide particles having a layered structure… wherein the first lithium composite oxide particles are secondary particles in which the primary particles agglomerate (Paragraph 8: the positive active material includes a lithium nickel-based composite oxide with a small-diameter particle. Paragraph 9: “The small-diameter particle may include secondary particles including a plurality of primary particles.”)
the first lithium composite oxide particles have an average particle size (D50) of 3.0 µm to 6.0 µm (paragraph 8: secondary particle, of the small-diameter particle, has a 1 μm to 8 μm average particle diameter)
an average size of the first lithium composite oxide particles ranges from 1.4 μm to 2.5 μm (paragraph 73: primary particles, of the small-diameter particle, have 100 nm to 900 nm average particle diameter)
For the primary particles, of the small-diameter particle, Kil teaches 100 nm to 900 nm (0.1 μm to 0.9 μm) average particle diameter, but claims 1 & 6 require 1.4 μm to 2.5 μm. MPEP 2144.05 (I) provides the law for this issue:
“Similarly, a prima facie case of obviousness exists where the claimed ranges or amounts do not overlap with the prior art but are merely close. Titanium Metals Corp. of America v. Banner, 778 F.2d 775, 783, 227 USPQ 773, 779 (Fed. Cir. 1985)… ‘The proportions are so close that prima facie one skilled in the art would have expected them to have the same properties.’”
Given that there is only a slight difference between Kil’s 0.1 μm to 0.9 μm and 1.4 μm to 2.5 μm in claims 1 & 6, and further given the fact that no criticality is disclosed for the claimed range, the claimed range is an obvious variant of Kil’s range.
Ko provides additional guidance. Ko describes a secondary battery with improved charge - discharge cycle durability (paragraph 7). Ko’s secondary battery includes a positive electrode active material with secondary particles formed by aggregation of primary particles (paragraphs 8 & 43). The average particle diameter of the primary particles can be 600 nm to 2 μm (paragraph 45).
It would have been obvious, to one of ordinary skill in the art, before the effective filing date of the invention, for Kil’s primary particles, of the small-diameter particle, to have a 600 nm to 2 μm (0.6 μm to 2 μm) diameter, as taught by Ko, as part of a secondary battery with improved charge - discharge cycle durability.
Ko’s 0.6-2 μm range overlaps the claimed 1.4-2.5 μm range. MPEP 2144.05 (II)(A) provides the law for this issue:
“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)”
Given that Ko’s 0.6-2 μm range is similar to and substantially overlaps the claimed range, and further given the fact that no criticality is disclosed for the claimed range, the 1.4-2.5 μm range in claims 1 & 6 is an obvious variant of Ko’s range.
Kil, however, fails to teach the following limitation of claims 1 & 6, which is taught by Hiratsuka:
the first lithium composite oxide particles have a dibutyl phthalate absorption value of 15 mL/100g to 27 mL/100g…
Hiratsuka describes a positive electrode active material with a lithium nickel composite oxide produced from nickel hydroxide with 1-5 μm particle size, and 10-30 mL/100g DBP value (abstract; paragraph 12). Hiratsuka states that (A) DBP less than 10 mL/100g results in fewer void spaces and decreased effective reaction area; and (B) DBP greater than 30 ml/100 g results in too many void spaces and degraded electrode pressing and packing characteristics (paragraph 24). Hiratsuka also describes how to control the DBP value (paragraph 24).
It would have been obvious, to one of ordinary skill in the art, before the effective filing date of the invention, to optimize the DBP absorption amount in the nickel-based lithium metal composite oxide of Kil’s large secondary particles and small secondary particles, as taught by Hiratsuka, to optimize effective reaction area, electrode pressing characteristics, and packing characteristics.
Hiratsuka’s 10-30 mL/100g range overlaps the claimed 15-27 mL/100g range. MPEP 2144.05 (II)(A) provides the law for this issue:
“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)”
Given that Hiratsuka’s 10-30 mL/100g range is similar to and substantially overlaps the claimed range, and further given the fact that no criticality is disclosed for the claimed range, the 15-27 mL/100g range in claims 1 & 6 is an obvious variant of Ko’s range.
Kil also teaches the following limitations of claims 1 & 6:
second lithium composite oxide particles having a layered structure… wherein the second lithium composite oxide particles are secondary particles in which primary particles agglomerate (paragraph 8: the positive active material includes a lithium nickel-based composite oxide with a large-diameter particle; the large-diameter particle includes secondary particles with a plurality of primary particles)
the second lithium composite oxide particles have an average particle size (D50) of 10.0 µm to 22.0 µm (paragraph 8: secondary particle, of the large-diameter particle, has a 10-20 μm average particle diameter)
an average primary particle size in the second lithium composite oxide particles ranges from 0.1 μm to 0.3 μm (paragraph 73: primary particles, of the large-diameter particle, have 200-700 nm average particle diameter; i.e. 0.2-0.9 μm diameter)
Kil’s 0.2-0.9 μm range overlaps the claimed 0.1-0.3 μm range. MPEP 2144.05 (II)(A) provides the law for this issue:
“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)”
Given that Kil’s 0.2-0.9 μm range is similar to and substantially overlaps the claimed range, and further given the fact that no criticality is disclosed for the claimed range, the 0.1-0.3 μm range in claims 1 & 6 is an obvious variant of Kil’s range.
Kil, however, fails to teach the following limitation of claims 1 & 6, which is taught by Kaneda:
the second lithium composite oxide particles have a dibutyl phthalate absorption value of 14 mL/100g to 22 mL/100g
Kaneda teaches a positive electrode active material with a lithium, nickel, manganese, cobalt composite oxide with 5-20 μm particle size, and 12-20 cm3/100g DBP (paragraphs 17, 20, & 81; cm3=ml=mL).
Kaneda is directed to a positive electrode active material for a battery with high energy density (paragraph 15). It would have been obvious, to one of ordinary skill in the art, before the effective filing date of the invention, for the nickel-based lithium metal composite oxide, in Kil’s secondary particle, of the large-diameter particle, to have DBP of 12-20 cm3/100 g, as taught by Kaneda, for high energy density.
Kaneda’s 12-20 range overlaps the claimed 14-22 range. MPEP 2144.05 (II)(A) provides the law for this issue:
“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)”.
Given that Kaneda’s range is similar to and substantially overlaps the claimed ranges, and further given the fact that no criticality is disclosed for the claimed ranges, the ranges in claims 1 and 6 are obvious variants of Kaneda’s range.
With regard to claims 2 and 7, modified Kil teaches the limitations of claims 1 and 6 as described above. Kil also teaches the following limitation of claims 2 and 7:
each of the first lithium composite oxide particles and the second lithium composite oxide particles are particles of a nickel cobalt manganese composite oxide (paragraphs 4, 95, & 98)
With regard to claims 5 and 10, modified Kil teaches the limitations of claims 1 and 6, as described above. Kil fails to teach the following limitations of claims 5 and 10, which are taught by Kaneda and Hiratsuka:
the first lithium composite oxide particles have a dibutyl phthalate absorption value of 18 mL/100g to 27 mL/100g, and the second lithium composite oxide particles have a dibutyl phthalate absorption value of 16 mL/100g to 22 mL/100g
The claimed 18-27 mL/100g and 16-22 mL/100g ranges are obvious over based on Hiratsuka’s 10-30 mL/100g (abstract and paragraphs 12 & 24), and Kaneda’s 12-20 cm3/100g range (paragraphs 17, 20, & 81), respectively, as discussed under claims 1 and 6 above.
Claims 3-4 and 8-9 are rejected under 35 U.S.C. 103 as being unpatentable over US20210135215A1 (Kil), US20200014023A1 (Ko), US20190248673A1 (Kaneda), and US20100068624A1 (Hiratsuka), as applied to claims 1-2 & 6-7, and further in view of US20210408528A1 (Chae). Kil fails to teach the following limitation of claims 3-4 and 8-9, which are taught by Chae:
Claim 3 & 8
a content of nickel in entire metal elements except for lithium in the first lithium composite oxide particles is 60 mol% or more (paragraphs 60-61)
Claim 4 & 9
a content of nickel in entire metal elements except for lithium in the second lithium composite oxide particles is 55 mol% or more (paragraphs 60-61)
Chae’s stoichiometric coefficient for Ni is 1-x-y-z. Chae states that x+y+z can be 0.01 to 0.2; therefore, nickel is 80 mol% (1-0.2) to 99 mol% (1-0.01) of the non-lithium metal elements. Note that Chae’s nickel-based lithium metal composite oxide, which can be a lithium-nickel-cobalt-manganese composite oxide (paragraphs 60-61), is used for Chae’s large and small secondary particles (paragraph 10).
Chae is directed to a positive electrode for a lithium secondary battery with high energy density (abstract; paragraphs 3-4, 40, 42, 46, & 48). It would have been obvious, to one of ordinary skill in the art, before the effective filing date of the invention, for Kil’s nickel content to be 80 mol% to 99 mol%, as taught by Chae, as part of a positive electrode for a lithium secondary battery with high energy density.
Claim 4 also recites:
the dibutyl phthalate absorption value of the second lithium composite oxide particles is based on an internal gap amount of the second lithium composite oxide particles
This is merely a recitation of the definition of the dibutyl phthalate absorption value. The cited prior art teaches the claimed dibutyl phthalate absorption value, and thus fulfills this claim limitation.
Claims 13-14 are rejected under 35 U.S.C. 103 as being unpatentable over US20210135215A1 (Kil), US20200014023A1 (Ko), US20190248673A1 (Kaneda), and US20100068624A1 (Hiratsuka), as applied to claims 1 & 6, and further in view of US20210135210A1 (Kawakita). Modified Chae, however, fails to teach the following limitation of claims 13-14, which is taught by Kawakita:
a Brunauer-Emmet-Teller (BET) specific surface area of the first lithium composite oxide particles is 0.54 m2/g to 0.69 m2/g
Kawakita teaches 0.1-0.6 m2/g BET specific surface area for optimal gap size and optimal binding between particles (paragraph 49). It would have been obvious, to one of ordinary skill in the art, before the effective filing date of the invention, for Kil’s small secondary particles to have 0.1-0.6 m2/g BET specific surface area, as taught by Kawakita, for optimal gap size and optimal binding between particles.
Kawakita’s 0.1-0.6 m2/g range overlaps the claimed 0.54-0.69 m2/g range. MPEP 2144.05 (II)(A) provides the law for this issue:
“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)”.
Given that Kawakita’s range is similar to and substantially overlaps the claimed range, and further given the fact that no criticality is disclosed for the claimed range, the range in claims 13-14 is an obvious variant of Kawakita’s range.
Claims 15-16 are rejected under 35 U.S.C. 103 as being unpatentable over US20210135215A1 (Kil), US20200014023A1 (Ko), US20190248673A1 (Kaneda), and US20100068624A1 (Hiratsuka), as applied to claims 1, 6, & 13-14, and further in view of US20210159495A1 (Li). Modified Chae fails to teach the following limitation of claims 15-16, which is taught by Li:
a Brunauer-Emmet-Teller (BET) specific surface area of the first lithium composite oxide particles is 0.18 m2/g to 0.36 m2/g
Li teaches a positive active material with secondary particle, formed by primary particle aggregation, with 0.3-1.5 m2/g BET specific surface area (paragraph 34). Li teaches these BET values for optimal contact area between the positive active material and the electrolyte, for dynamic battery performance, and for battery safety (paragraph 35). It would have been obvious, to one of ordinary skill in the art, before the effective filing date of the invention, for Kil’s large secondary particles to have 0.3-1.5 m2/g BET specific surface area, as taught by Li, for optimal contact area between the positive active material and the electrolyte, for dynamic battery performance, and for battery safety.
Li’s 0.3-1.5 m2/g range overlaps the claimed 0.18-0.36 m2/g range. MPEP 2144.05 (II)(A) provides the law for this issue:
“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)”.
Given that Li’s range is similar to and substantially overlaps the claimed range, and further given the fact that no criticality is disclosed for the claimed range, the range in claims 15-16 is an obvious variant of Li’s range.
Conclusion
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/R.G.W./Examiner, Art Unit 1721
/ALLISON BOURKE/Supervisory Patent Examiner, Art Unit 1721