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.
Status of Claims
Claims 1-11 are pending in the application. Claim 2 is withdrawn. Claims 1 & 3-11 were rejected in the office action mailed 2/27/2026. Claims 1 & 3-11 are presently examined.
Response to Amendment / Arguments
The 4/20/2026 amendment, in response to the 2/27/2026 office action, has been entered.
Applicant's arguments, regarding the 112(b) rejections, have been fully considered, but they are not persuasive.
Claim 1 states that “the positive active material particle includes primary particles and a secondary particle formed by aggregation of the primary particles”. Dependent claim 10 then states that “the ratio of the size of the secondary particle to the size of each one of the primary particles is 1 or less”.
Logically, if the secondary particle is formed by aggregation of the primary particles, then the secondary particle must be larger than the primary particles. Claim 10, however, requires a relationship that is inconsistent with the claim 1 requirement of aggregation. Claim 10 requires that the secondary particle is the same size as, or smaller than, the primary particles.
Applicant argues that “the method for measuring the primary particle size is different from the method for measuring the secondary particle size”. It seems that the Applicant is arguing that the particles are measured by a defective mechanism that results in a measurement of the larger particles that is smaller than or equal to a measurement of the smaller particles.
These are not method of particle measurement claims. The following claim limitations are interpreted to mean the actual particle sizes, and not the size determined by a defective mechanism:
Claim 1: “a ratio of a size of the secondary particle to a size of each one of the primary particles is 3 or less”
Claim 10: “the ratio of the size of the secondary particle to the size of each one of the primary particles is 1 or less”
Examiner encourages Applicant to file a continuation application for method of particle measurement claims.
Applicant’s claim amendment overcame the 35 U.S.C. 102 rejections; however, the claims remain rejected under 35 U.S.C. 103. Applicant's arguments, regarding an anticipated 35 U.S.C. 103 rejection, have been fully considered but they are not persuasive.
Applicant argues that unexpected results should overcome the 35 U.S.C. 103 rejection of the following claim 1 limitation:
“a ratio of a size of the secondary particle to a size of each one of the primary particles is 3 or less”
Applicant presents the following tables to illustrate unexpected results:
Table 1. Specification paragraph 125.
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media_image1.png
354
1116
media_image1.png
Greyscale
Table 2. Specification paragraph 142.
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media_image2.png
704
1458
media_image2.png
Greyscale
Table 3. Declaration submitted 2/5/2026.
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media_image3.png
182
1164
media_image3.png
Greyscale
Table 4. Declaration submitted 2/5/2026.
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media_image4.png
184
1166
media_image4.png
Greyscale
Table 5. Declaration submitted 2/5/2026.
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media_image5.png
182
1166
media_image5.png
Greyscale
Type A in Table 1, Type C in Table 2, and Table 3 are not useful data because secondary particle size = primary particle size. This is inconsistent with the claim 1 requirement of “secondary particle formed by aggregation of the primary particles” [note plural particles]. If the secondary particle is formed from multiple primary particles, then the secondary particle must be larger than the primary particles it is made of.
Remaining data is presented below in a table prepared by the Examiner (RE = Reference Example, E = Example, CE = Comparative Example, 2o/1o = secondary particle size / primary particle size):
Example
2o/1o
Fibrous
Initial DCR
DCR increase
Table 1
RE 1-1
8
present
1.517
Table 1
RE 1-2
8
absent
1.695
Table 2
RE 2-2
14
present
38
Table 2
RE 2-3
14
present
32
Table 4
E 2-6
3
present
8
Table 5
CE 2-3
3
absent
15
The Reference Examples RE 1-1 & RE 1-2 are not useful for comparison to the other examples, because they show Initial DCR data, but the other examples show DCR increase data. CE 2-3 is helpful for showing the effect of lack of the fibrous conductive agent, but is not helpful for showing the effect of 2o/1o because it lacks the fibrous conductive agent.
The only remaining data are RE 2-2 & RE 2-3, with 2o/1o = 14 and DCR increase = 38 & 32 compared to E 2-6 with 2o/1o = 3 and DCR increase = 8. It is insufficient to prove unexpected results of the ≤ 3 range with examples showing results only at 2o/1o = 14 & 3.
Furthermore, the examples also differed in mass ratio of the positive active material particle, CNT, CB, and the binder not considered. The above results could be due to differences between these ratios, and not due to difference in 2o/1o.
Examiner suggests that Applicant provide more examples, with everything the same except for 2o/1o, presented in a single table, with the same output data (Initial DCR data, DCR increase data, or both) for all examples. These examples should include several different 2o/1o values across the claimed range and several different 2o/1o values with 2o/1o > 3.
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, 3-7, & 9-11 are rejected under 35 U.S.C. 103 as being unpatentable over US20190280284A1 (Azami).
Azami teaches the following claim 1 limitations:
A positive electrode for an energy storage device, comprising a positive active material layer (paragraph 18), wherein
the positive active material layer includes a positive active material particle (paragraphs 20-22) and a fibrous conductive agent (paragraph 25: carbon nanotubes)
wherein the positive active material particle includes primary particles (paragraphs 20-22: primary particles) and a secondary particle formed by aggregation of the primary particles (paragraph 20: “A secondary particle is an aggregate of multiple primary particles.”)
Claim 1 also states:
a ratio of a size of the secondary particle to a size of each one of the primary particles is 3 or less,
Azami teaches 300 nm to 700 nm primary particle size (paragraph 22) and 1 μm to 12 μm [1000 nm to 12,000 nm] secondary particle size (paragraph 23). Ratios are 1000/700 to 12,000/300 = 1.4 to 40. Azami’s 1.4 to 40 range overlaps the claimed ≤ 3 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 Azami’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 claim 1 is an obvious variant of Azami’s range.
Claim 1 also states:
the size of each one of the primary particles being an average value of particle sizes of arbitrary fifty primary particles constituting the positive active material particle observed by a scanning electron microscope (SEM),
the size of the secondary particle being a value at which a volume-based integrated distribution calculated in accordance with JISZ-8819-2 (2001) is 50% (D50: median size) based on a particle size distribution measured by a laser diffraction/scattering method for a diluted solution obtained by diluting positive active material particles with a solvent in accordance with JIS-Z-8815 (2013)
This method of determining particle size does not limit the scope of this apparatus claim for examination purposes. Examiner encourages Applicant to file a divisional application for this size-determination method.
With regard to claim 3, Azami teaches the limitations of claim 1 as described above. Azami also teaches the following claim 3 limitation:
the positive active material layer further includes a granular conductive agent (paragraph 26: carbon black)
With regard to claim 4, Azami teaches the limitations of claims 1 & 3 as described above. Azami also teaches the following claim 4 limitation:
the fibrous conductive agent and the granular conductive agent are carbonaceous materials (paragraph 26: carbon nanotubes and carbon black)
With regard to claim 5, Azami teaches the limitations of claim 1 as described above. Azami also teaches the following claim 5 limitation:
the fibrous conductive agent has an average diameter of 100 nm or less (paragraph 26: carbon nanotube average diameter is 10 nm to 30 nm)
With regard to claims 6 & 11, Azami teaches the limitations of claim 1 as described above. Claims 6 & 11 state:
Claim 6
a content of the fibrous conductive agent in the positive active material layer is 3% by mass or less
Claim 11
a content of the fibrous conductive agent in the positive active material layer is 0.05% by mass or more and 5% by mass or less
Azami teaches 1-10 mass% carbon nanotubes in the positive electrode mixture layer (paragraph 29). Thus, Azami’s 1-10 mass% range overlaps the claimed ≤ 3 mass% range (claim 6) and the 0.05 to 5 mass% (claim 11). 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 Azami’s range is similar to and overlaps the claimed range, and further given the fact that no criticality is disclosed for the claimed range, the ranges in claims 6 & 11 are obvious variants of Azami’s range.
In the Remarks, Applicant does discuss unexpected results associated with the fibrous conductive agent; however, these unexpected results are associated with a secondary particle size to primary particle size ratio. This ratio is not part of the claims because secondary particles are optional.
With regard to claim 7, Azami teaches the limitations of claims 1 and 3 as described above. Azami also teaches the following claim 7 limitation:
a content of the fibrous conductive agent with respect to a total content of the fibrous conductive agent and the granular conductive agent in the positive active material layer is 30% by mass or more and 70% by mass or less (paragraph 29: mass% carbon nanotubes in the positive electrode mixture layer is 1-10 mass%; paragraph 31: mass% carbon black in the positive electrode mixture layer is 1-10 mass%)
Azami’s content of the fibrous conductive agent is the following (c. black = carbon black & CNT = carbon nanotubes):
1
c
.
b
l
a
c
k
1
c
.
b
l
a
c
k
+
10
C
N
T
=
9
%
10
c
.
b
l
a
c
k
10
c
.
b
l
a
c
k
+
1
C
N
T
=
91
%
Azami’s 9-91 mass% range overlaps the claimed 30-70 mass% range. MPEP 2144.05 (II)(A), quoted above, provides the law for this issue. Given that Azami’s range is similar to and overlaps the claimed range, and further given the fact that no criticality is disclosed for the claimed range, the range in claim 7 is an obvious variant of Azami’s range.
With regard to claim 9, Azami teaches the limitations of claim 1 as described above. Azami also teaches the following claim 9 limitation:
An energy storage device comprising the positive electrode according to claim 1. (title, abstract, paragraph 17)
With regard to claim 10, Azami teaches the limitations of claim 1 as described above. Claim 10 states:
the ratio of the size of the secondary particle to the size of each one of the primary particles is 1 or less (paragraphs 22-23: 0.025 to 0.7 or 0.43)
Secondary particles are optional (see claim 1), so it is not required for the prior art to teach this ratio.
Also, as discussed under the 112(b) rejection above, it is impossible to fulfill the claim 10 limitation within the context of independent claim 1 limitations. Therefore, claim 10 is disregarded for prior art analysis.
Claim 8 is rejected under 35 U.S.C. 103 as being unpatentable over US20190280284A1 (Azami), as applied to claim 1, and further in view of US20080131782A1 (Hagiwara). Azami teaches the limitations of claim 1 as described above. Azami, however, fails to teach the following claim 8 limitation, which is taught by Hagiwara:
the positive active material particle is a lithium transition metal composite oxide having an a-NaFeO2-type crystal structure (paragraph 10: positive electrode active material LiMO2 having the a-NaFeO2 structure; paragraph 12: M is a transition metal)
Hagiwara states that the LiMO2 with a-NaFeO2 structure positive electrode active material is useful for suppressed charging/discharging capacity degradation (paragraph 10).
It would have been obvious, to one of ordinary skill in the art, before the effective filing date of the invention, for Azami’s positive electrode active material to include LiMO2 with a-NaFeO2 structure, as taught by Hagiwara, for suppressed charging/discharging capacity degradation.
Conclusion
THIS ACTION IS MADE FINAL. Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a).
A shortened statutory period for reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply is filed within TWO MONTHS of the mailing date of this final action and the advisory action is not mailed until after the end of the THREE-MONTH shortened statutory period, then the shortened statutory period will expire on the date the advisory action is mailed, and any extension fee pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the date of this final action.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to ROBERT WEST whose telephone number is 703-756-1363 and email address is Robert.West@uspto.gov. The examiner can normally be reached Monday-Friday 10 am - 7 pm ET.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Allison Bourke can be reached at 303-297-4684.
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/R.G.W./Examiner, Art Unit 1721
/ALLISON BOURKE/Supervisory Patent Examiner, Art Unit 1721
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