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 .
Election/Restrictions
Applicant’s election of Group II, claim(s) 4–9, in the reply filed on 02/25/26 is acknowledged. Claim(s) 1–3 is/are withdrawn from further consideration pursuant to 37 CFR 1.142(b) as being drawn to a nonelected invention, there being no allowable generic or linking claim. Election was made without traverse.
Claim Objections
It is recommended that Applicant amend the claims as follows:
In claim 9, line 4, “the positive active material” is suggested to read “the positive electrode active material” for consistent claim terminology with respect to claim 4.
Appropriate correction is required.
Claim Rejections - 35 USC § 112
Claim 5 is rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention.
Claim 5 recites “the precursor is a lithium transition metal oxide” in lines 2 and 3. In depending from claim 4, which recites “mixing a lithium source with a precursor” (line 3), it is structurally unclear that the precursor itself may be a lithium transition metal oxide, as such is intended to instead be the final product (see spec.’s ¶ 32–37 and exs.).
¶ 32–35 describe that the precursor may be one from which a Ni-rich lithium transition metal oxide is prepared, wherein the precursor may be a transition-metal hydroxide with nickel content ≥ 70 mol% based on the total mole number of transition metals, though such is exemplary (by using permissive “may” language) and, thus, does not require the precursor to be a transition-metal hydroxide. Thus, for this Office Action claim 5 will be interpreted to require any “precursor” with Ni content ≥ 70 mol% based on the total mole number of transition metals and through which a Ni-rich lithium transition metal oxide is prepared upon mixing with the lithium compound of claim 4, which appears consistent with ¶ 32–37 and the claims as a whole.
Appropriate correction is required.
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.
Claim(s) 4–9 is/are rejected under 35 U.S.C. 103 as being unpatentable over Bai et al. (WO 2021068448 A1) (Bai).
Regarding claim 4, Bai discloses a method for preparing a positive electrode active material for a lithium secondary battery (e.g., Abstract, ¶ 0053), comprising a first firing step of mixing a lithium source with a precursor and heat treating the resultant mixture to obtain a fired product (S100/200 of first mixing and first sintering of hydroxide and Li compound, ¶ 0054–0063; see also Ex. 1, ¶ 0091).
Bai further discloses a second firing step of mixing the fired product with a first coating agent and heat treating the resultant mixture to form a surface protective layer (S300/400 of second mixing and second sintering, ¶ 0066–0071; see also Ex. 1, ¶ 0092).
Although embodying alumina as first coating agent in Ex. 1 (¶ 0092), Bai broadly discloses that element M can be used to coat the active material, where M may be B to shield the active sites on the surface of the active material to reduce electrolytic side reactions (¶ 0048).
Although Bai fails to explicitly embody a first coating agent of a B source, considering that Bai is analogous prior art to the claimed invention because they pertain to the same field of endeavor, namely B-coatings in positive electrode active material, it would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to incorporate a first B source as first coating agent with the reasonable expectation of successfully forming the surface protection layer atop the fired active material to reduce electrolytic side reactions, as suggested by Bai.
Bai further discloses a water-washing step of removing unreacted lithium remaining on the surface of the fired product obtained from the second firing step (¶ 0082; see also Ex. 1, ¶ 0093); and a coating step of drying the product of the water-washing step and heat treating the dried product with a second coating agent to form a positive electrode active material (S500/600 of third mixing and calcining, ¶ 0074–0079 (and dried after washing before S500, per ¶ 0082); see also Ex. 1, ¶ 0093 and 0094).
Bai discloses that the second coating agent is uniformly coated on the surface of the primary-coated active material to further shield the active sites to further reduce electrolytic side reactions to further improve thermal stability and cycle performance, where the second coating agent may be B2O3 (¶ 0076; see also Ex. 1, ¶ 0094).
Although Bai fails to explicitly embody a second coating agent of a second B source alongside the first B source as first coating agent, it would have been obvious to incorporate a second B source as part of the recited “coating step” with the reasonable expectation of further shielding the active material from side reactions to further improve thermal stability and cycling performance, as suggested by Bai.
Regarding claim 5, as best understood, Bai discloses the method according to claim 4, wherein the precursor is a transition metal hydroxide (e.g., Ni0.88Co0.06Mn0.03Al0.03(OH)2, Ex. 1, ¶ 0091) that forms a lithium transition metal oxide (upon final calcining, e.g., ¶ 0094; see also ¶ 0042), wherein the (resultant) lithium transition metal oxide has a nickel content of 88 mol% based on the total mole number of transition metals in the lithium transition metal oxide (necessarily because, as seen in general formula of ¶ 0042, Li is intercalated at 1:1 molar ratio of Li:transition metals, so precursor above would define molar ratios of transition metals), satisfying ≥ 70 mol%.
Regarding claim 6, Bai discloses the method according to claim 4, wherein the heat treatment temperature in the first firing step is 1.23 times the heat treatment temperature in the second firing step (e.g., 740°C versus 600°C, Ex. 1, ¶ 0091 and 0092), satisfying 0.75–1.5 times.
Regarding claim 7, Bai discloses the method according to claim 4, wherein the water-washing step comprises mixing the fired product with water at a weight ratio of 200%, falling within 50–200% (e.g., Ex. 1, ¶ 0093); and agitating the mixture of fired product and water (stirring at 600 rpm, Id.).
Regarding claim 8, Bai discloses the method according to claim 4, wherein the second B source is B2O3 (e.g., Ex. 1, ¶ 0094).
Although failing to explicitly disclose a first B source of B2O3, Bai generally discloses that, when coating with B, the source may be, e.g., B2O3 or H3BO3 (¶ 0076).
It would have been obvious to one of ordinary skill in the art, before the claimed invention's effective filing date, that, when selecting B as first coating agent, the B must necessarily be incorporated from some raw material, and, as with Bai’s second coating agent/second B source, the skilled artisan would find it obvious to incorporate the first B source as, e.g., B2O3 or H3BO3 with a reasonable expectation of successful coating.
Regarding claim 9, Bai discloses the method according to claim 4.
Bai generally discloses that the mass ratio of the active-material core to coating element in first coating agent is 1:(0.0005~0.001)—i.e., 500~1000 ppm—and the mass ratio of the primary-coated product to coating element in the second coating agent is 1:(0.001~0.01)—i.e., 1000~10000 ppm—to improve capacity, thermal stability, and cycle performance (¶ 0069, 0077).
Although not specifying 200–5000 ppm B in the positive active material, as Bai discusses above, the skilled artisan would recognize that enough active material must be present for capacity and make up the bulk of the material (as seen in, e.g., ¶ 0003/0004), while enough B must be present to provide the desired protection, thermal stability, and cycling improvement. To balance these effects, then, it would have been obvious to arrive at the recited range by routinely optimizing B’s wt% in the active material (MPEP 2144.05 (II)).
Conclusion
The cited art made of record and not relied upon is considered pertinent to applicant's disclosure:
CN 104409700 A: double-coating active material with element such as B through apparent one-step coating/heating.
US 20180261832 A1: active material that may be double-coated with first layer including boron and second layer including a boron oxalate, though it is unclear if such includes water-washing.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to JOHN S MEDLEY whose telephone number is (703)756-4600. The examiner can normally be reached 8:00–5:00 EST M–Th and 8:00–12:00 EST F.
Examiner interviews are available via telephone, in-person, and video conferencing using a USPTO supplied web-based collaboration tool. To schedule an interview, applicant is encouraged to use the USPTO Automated Interview Request (AIR) at http://www.uspto.gov/interviewpractice.
If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Jonathan Leong, can be reached on 571-270-192. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
Information regarding the status of published or unpublished applications may be obtained from Patent Center. Unpublished application information in Patent Center is available to registered users. To file and manage patent submissions in Patent Center, visit: https://patentcenter.uspto.gov. Visit https://www.uspto.gov/patents/apply/patent-center for more information about Patent Center and https://www.uspto.gov/patents/docx for information about filing in DOCX format. For additional questions, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). If you would like assistance from a USPTO Customer Service Representative, call 800-786-9199 (IN USA OR CANADA) or 571-272-1000.
/J.S.M./Examiner, Art Unit 1751
/JONATHAN G LEONG/Supervisory Patent Examiner, Art Unit 1751 5/8/2026
Prosecution Insights