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 .
Remarks
Claim 1 has been amended. Claim 2 has been cancelled. Claims 3-5, 7, 14-16 are as previously presented. Claims 1, 3-5, 7, 14-16 are presently presented.
Status of objections and rejections
The rejection below has been modified as necessitated by the applicant’s amendments.
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) 1, 3, 5, 7, and 14-16 is/are rejected under 35 U.S.C. 103 as being unpatentable over Jang (US20170170480A1) and in view of Maeda (WO2012133143A1) and Chang (US20110062378A1).
Regarding claim 1 and 16, Jang discloses a positive electrode material comprising: a positive electrode active material [0002, 0012-0014, Jang]; and a coating layer formed on a surface of the positive electrode active material [0002, 0012-0014, Jang], wherein the positive electrode active material is represented by Formula 1 [0049-0051, Jang discloses a general formula and provides a specific example of LiNi0.6 Mn0.2 Co0.2 O2 which reads on the claimed formula when x=1; y=0.6; z=0.2; w=0.2; v=0; p=0].
Jang discloses a coating layer with a conductive nanoparticle and polyimide [0016, Jang]. Additionally Jang discloses a known and technique in which a metal oxide coating layer may be formed on a positive active material by forming a finely dispersed nano-sized particle coating layer.
Jang is explicitly silent to: 1) a coating layer where the polyimide is discrete locations (instant claim 1). 2) the surface area coverage of the coating layer (instant claim 1). 3) the coating layer wherein the polyimide is discrete locations spaced apart from one another as nano-sized polyimide powder particles (instant claim 16).
In regards to 1) and 3), Maeda discloses a composite film comprised of polyimide resin fine particles (0.05 µm – 1.5 µm) and inorganic particles being mixed with a cellulose-based dispersant and coated onto a positive active material [page 8 lines 1-10, page 12 lines 1-5; Maeda].
The examiner notes, that because the polyimide fine particles (and inorganic materials) are uniformly dispersed in the cellulose-based dispersant [page 30 line 1-10, page 34 line 1-10, Maeda] this would produce a coating layer with polyimide being arranged in a plurality of discrete locations spaced apart from one another as nano-sized (2.5um or less reads on BRI of nanosized) polyimide powder particles which reads on island shape.
Jang and Maeda are analogous as both discloses a polyimide “coating layer” utilized to suppress contact/reactions between the electrode and electrolyte ([0033], Jang; [page 11 line 1-7], Maeda).
Prior to the effective filing date, one of ordinary skill within the arts would find it obvious to modify Jang such that in the coating layer at least the polyimide was used as fine particles dispersed in a dispersing agent and coated on the surface of the positive active material. Doing so can 1) produce an active material with the durability and heat resistance of polyimide while simultaneously accommodate volume changes [page 34 line 11-15, Maeda]. 3) produce a film that exhibits high strength, excellent adhesion, and the ability to suppress reactions between the electrolyte and the electrode [page 11 line 1-7, Maeda].
In regards to 2), Chang discloses a lithium transition metal oxide active material (similar to the materials of Park and Song) [0027-0030, Chang] with a formation area of the coating layer is in a range of 2% to 80% based on a total surface area of the positive electrode active material [0043,]. Chang teaches that the coverage area is an art recognized result effective variable where too large an area reduces lithium ion mobility and too small limits the desirable effects ([0043]).
Therefore it would have been obvious, prior to the effective filing date, to use the 20-80% taught by Chang in modified Jang in order to optimize ion mobility and desirable effects of the coating layer as taught by Chang ([0043]).
Regarding claim 3, modified Jang teaches of using particles preferably within a range of 0.05-1.5µm [page 12 line 1-5, Maeda] is silent to the size of the polyimide islands used in the coating layer.
However, Jang’874 discloses a lithium-containing positive electrode active material coating layer comprised of islands with a size of the island is in a range of 1 nm to 800 nm [0046, Jang’874 discloses island with a size of 100-5000 nm. In the case where the claimed ranges "overlap or lie inside ranges disclosed by the prior art" a prima facie case of obviousness exists, see MPEP 2144.05].
Prior to the effective filing date, one of ordinary skill within the arts would be motivated to modify Jang such that the size of the island coating layer was in the same range as disclosed by Jang as this can improve conductivity of the active material [0046, Jang]. Furthermore, barring any criticality or unexpected results the size of the islands is a matter of mere change in size/proportion, see MPEP 2144.04.IV.
Regarding claim 5, modified Jang discloses the coating layer further comprising Sb, Al, and Zn [0016, Jang].
Regarding claim 7, Jang as modified above discloses a lithium nickel metal oxide wherein, in Formula 1, y=0.6; z=0.2; w=0.2 [0050, 0097, Jang].
Regarding claim 14, Jang as modified above discloses a positive electrode for a lithium secondary battery [0014, Jang].
Regarding claim 15, Jang as modified above discloses a lithium secondary battery [0117-0118, Jang].
Claim(s) 4 is/are rejected under 35 U.S.C. 103 as being unpatentable over modified Park as applied to claim 1 above, and further in view of Choi (WO2015053446A1).
Regarding claim 4, modified Jang is silent to the wt% of the polyimide coating layer.
However, Choi discloses coating a lithium ion battery with an active material with composite oxide of lithium with a coating layer in the shape of an island included in an amount of 0.03 wt% to 3 wt% based on a total weight of the positive electrode material [0022-0023, claim 4, Choi discloses using a coating layer in 0.3-3.0 wt% with respect to the total amount of the positive electrode active material which reads on the applicant’s claimed range, see MPEP 2144.05].
Prior to the effective filing date, one of ordinary skill within the arts would be motivated to modify Jang such that the amount of the coating layer was applied within the range as disclosed by Choi. The amount of lithium remaining in the positive electrode active material can be reduced by 50 to 100% by weight compared to the amount of lithium remaining in a compound capable of reversible intercalation and deintercalation of lithium that does not include the coating layer [0024, Choi].
Response to Arguments
Applicant's arguments filed 03/02/2026 have been fully considered but they are not persuasive. See below for additional details.
First, applicant argues that Jang teaches away from less than 100% coverage of the active material. However, the examiner respectfully disagrees with this. Jang teaches that one cause for capacity reduction in an electrochemical cell is the side reactions (degradation) that takes place between the positive electrode and the electrolyte [0005, 0011, Jang]. Which one can prevent by covering the positive active material with a coating layer that can prevent contact between the electrolyte and the positive electrode active material [0012, 0020, Jang]. In Jang’s disclosed example all active materials are covered by a coating layer with the exception of comparative example 1 which has no coating layer. The result is that this one example had worse capacity retention rate. As such, Jang does teach away from the absence of a coating layer, but they do not teach away from using a coating layer with less than 100% as argued by the applicant.
Chang then takes this one step further and notes that incorporating a coating layer onto a positive active material does prevent direct contact between the electrolyte and the active material [0020, 0031, Chang]. As such, both Jang and Chang acknowledge the same problem in which the electrolyte may react with the positive active material and degrade the battery. As such, one may prevent this by incorporating a covering layer onto their positive active material. However, Chang notes that ion mobility decreases as the area of the covering layer increases [0043, Chang].
As such, one of ordinary skill within the arts would appreciate that providing a coating layer on the positive active material prevents degradation of the positive electrode and electrolyte. But in doing so there is a trade off with ion mobility. As such, one would choose a coating area coverage that fit their needs.
Next applicant argues no motivation to arrive at the claimed invention because Maeda uses their polyimide coating layer to coat a metal substrate. To which the examiner respectfully disagrees. Maeda notes that their polyimide coating layer contains cellulose to prevent the aggregation of the polyimide particles in their coating layer [page 4 line 8-14, page 23 line 7-19, Maeda]. Additionally, it was noted that this coating layer is able to suppress reactions between electrolyte and electrodes [page 11 line 6-7, Maeda]. Jang notes that the positive active material may be prepared by making a slurry with a binder (e.g. cellulose based materials), a conductor, a filler and a dispersant to surface coated the positive active material [0071, 0074, Jang].
Both Jang and Maeda teach of using cellulose based material as a dispersant/binder and the use of polyimide in their coating layers. The examiner maintains that one of ordinary skill within the arts could look at the cellulose/polyimide particle coating layer of Maeda and modify Jang such that the coating layer on the positive active materials contains a coating layer containing cellulose/polyimide particles.
Additionally, the teachings of Jang and Maeda are not fundamentally different as both teach of a coating layer that may be used to suppress contact between the electrolyte and electrode surface (as noted above).
Finally applicant argues there is no reasonable expectation of success as the proposed modification of Jang and Maeda would “represent a fundamental redesign, not a routine substitution”. To which the examiner disagrees. The applicant does not explicitly state how this would be a fundamental redesign or why there is no degree of predictability of success. The examiner notes that Jang teaches that their positive active material is coated in a polyimide layer and a cellulose binder may be used with the active material, doing so suppress contact with the active material and electrolyte. Maeda teaches that one may combine cellulose and polyimide particles into a single coating layer and have it still suppress electrolyte contact. Both arts teach of how cellulose and polyimides may be used to suppress contact with the electrolyte. As such, the examiner maintains that there is at least some degree of predictability. To which the applicant has acknowledged is the requirement to met obviousness.
No further arguments were presented, the examiner maintains their rejection.
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure. Cho (US20190067682A1) discloses a carbon active material with a (discontinuous) polyimide coating layer. Won (US20150228973A1) discloses a positive active material with an island coating layer.
Applicant's amendment necessitated the new ground(s) of rejection presented in this Office action. Accordingly, THIS ACTION IS MADE FINAL. See MPEP § 706.07(a). 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 nonprovisional extension fee (37 CFR 1.17(a)) 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 mailing date of this final action.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to QUINTIN DALE ELLIOTT whose telephone number is (703)756-5423. The examiner can normally be reached M-F 8:30-6pm (MST).
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Miriam Stagg can be reached on 5712705256. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/QUINTIN D. ELLIOTT/Examiner, Art Unit 1724 /MIRIAM STAGG/Supervisory Patent Examiner, Art Unit 1724
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