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 .
Information Disclosure Statement
The information disclosure statement (IDS) submitted on February 6, 2024 has been considered by the examiner.
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 non-obviousness.
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 1-8, 10 and 12 are rejected under 35 U.S.C. 103 as being unpatentable over Sikha et al. (US20160013480, hereafter Sikha).
Regarding Claim 1, Sikha teaches a cathode (¶[0014] – [0019], Figs. 2A-7) including a cathode current collector (¶[0027], ¶[0035]-[0036], 111, 113) with a first cathode active material layer and a second cathode active material layer (Claim 1) on the cathode current collector (¶[0038], claims 1-15).
The first cathode active material (¶[0041]) layer comprises first cathode active material particles (¶[0043]) and a first binder (¶[0040], [0073]). The first cathode active material particles contain bimodal particles including large-scaled particles and small-scaled particles. The large-scaled particles have an average diameter (D50) of 10 µm, which reads on the claimed (D50) value from 10 µm to 20 µm (¶[0065]–[0068]). As the particles sizes taught in Sikha overlap with the claimed range, it would have been obvious to one of ordinary skill in the art to choose the large-scaled particles having average diameter of 10 microns because it is taught as an exemplary average particle size for bi-modal particles (MPEP 2144.05). The reference includes small-scaled particles having an average diameter of 3 and 6 microns, which fall within the claimed range of 1 µm to 9 µm (¶[0065]). The reference teaches that exemplary average particle sizes for the bi-modal particles include 3, 6 and 10 microns (¶[0065]). It would have been obvious to choose the small-scaled particles having an average diameter of 3 or 6 microns because they are taught as an exemplary average particle size for bi-modal particles. The reference teaches different cathodically active materials used for each layer, having different particle sizes, which allow for easier packing of the particles to achieve a desired density/porosity in each individual layer. One of ordinary skill in the art would have been motivated to choose these particles size to achieve ease of packing for each material layer (MPEP 2144.05).
Sikha teaches a second cathode active layer on the first cathode active layer (Abstract). Sikha teaches an exemplary structure wherein the second cathode material layer has a particle size from 1 to 6 microns [0068], which fall within the claimed range of 1 to 20 microns.
With regard to the first cathode active material, Sikha is silent to a content of the large-scaled particles being in the range of 50 to 80 wt%, and the small-scaled particles being in a range of 20 to 50 wt% based on a total weight of the first cathode active material particles. The reference teaches a bi-modal distribution for the large- and small-scaled particles in the first active layer as well as exemplary average diameters for these particles, so the combination of the first active layer material particles being bi-modally distributed with the average diameters of these particles being the exemplary sizes disclosed in the reference that fall within the claimed weight percentage ranges. It would have been obvious to one of ordinary skill in the art to formulate a first cathode active material layer with large- and small-scaled particles that fall within these weight percentage ranges (in the range of 50 to 80 wt%, and the small-scaled particles being in a range of 20 to 50 wt% based on a total weight of the first cathode active material particles) in order to form a high capacity electrode layer having a high active material density ([0062-0067], abstract). The reference teaches having cathodically active materials of different sizes allow for easier packing of particles to achieve desired density and porosity of each material layer. It would have been obvious to try various amounts of each of the materials taught in order to achieve a desired density or porosity of the material layer (MPEP 2144.05).
The reference does not specifically teach the second binder wt% to be equal to or less than the first binder wt%. However, Sikha teaches a content of the second binder based on a total weight of the second cathode active material layer may be less than or equal to a content of the first binder based on the total weight of the first cathode active material layer (¶[0056]) and the content of the second binder may be less than 1 wt% (¶[0045], [0056]). The reference teaches the first slurry mixture may contain up to about 15 wt% of binding agent (¶[0045]), and it teaches the second slurry mixture may contain up to about 10 wt% of binding agent (¶[0056]). The reference teaches the bottom of the range of the weight percentage of the second binder is about 1 wt%, which includes values that are slightly less than 1%. It would have been obvious to one of ordinary skill in the art to formulate the binder weight percentages so that a content of the second binder based on a total weight of the second cathode active material layer is less than or equal to a content of the first binder based on a total weight of the first cathode active material layer because the reference teaches using a higher percentage of binder for the first layer (up to about 15%) and a lower percentage for the second layer (up to about 10%). It is well-known in the art that decreasing the amount of binding agent allows for an increased amount of active material which directly relates to increased energy output/performance. One of ordinary skill in the art would have been motivated to use this known technique to yield predictable results with a reasonable expectation of success ([0026], MPEP 2143, KSR).
Regarding Claim 2, Sikha teaches the solids of the second binder may comprise between about 1 – 4 wt% of the binding agent (¶[0056]). The range taught in the reference is understood to include values that are slightly lower than 1%, which would reasonably fall within the claimed range of 0.3 to 0.5 wt%. 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).
Regarding Claim 3, Sikha teaches the content of the first binder is 1 wt% or more based on the total weight of the first cathode active material layer (¶[0045], examples [0101]). 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).
Regarding Claim 4, Sikha teaches the content of the first binder is in a range from 1.0 wt.% to 1.2 wt.% based on the total weight of the first cathode active layer (¶[0045]). 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).
Regarding Claim 5, Sikha teaches the first cathode active material particles have a distribution of a bi-modal form in which the large-scaled particles and the small-scaled particles are mixed (¶[0065]).
Regarding Claim 6, Sikha teaches the second cathode active material particles include a distribution in a unimodal form (¶[0065]).
Regarding Claim 7, Sikha teaches each thickness of the first cathode active material layer and the second cathode active material layer falls within the claimed range of 50 µm to 200 µm (¶[0102]). In the case where the claimed ranges “overlap or lie inside ranges disclosed by the prior art” a prima facie case of obviousness exists.
Regarding Claim 8, Sikha teaches a thickness ratio of the second cathode active material layer relative to the first cathode material layer that falls within in the claimed range of 1/9 to 9 (¶[0068]). In the case where the claimed ranges “overlap or lie inside ranges disclosed by the prior art” a prima facie case of obviousness exists.
Regarding Claim 10, Sikha teaches that the first cathode active layer and the second cathode active material layer each include a conductive material (see [0046-0047] and [0056]).
Regarding Claim 12, Sikha teaches a lithium secondary battery (Abstract, ¶[0006]) and an anode facing the cathode (¶[0032]).
Claim 9 is rejected under 35 U.S.C. 103 as being unpatentable over Sikha as applied to claims 1, and further in view of Inagaki et al. (US 2006/0216600), Inagaki hereinafter.
Regarding Claim 9, Sikha teaches all of the limitations of Claim 1, and it also teaches that each of the first cathode active material particles and the second cathode active material particles includes a lithium-nickel composite metal oxide (¶[0006]). However, Sikha does not expressly teach that the molar ratio of nickel among metal elements excluding lithium included in the lithium-nickel metal oxide is 0.8 or more.
Inagaki teaches a battery pack for a vehicle comprising a lithium ion battery having a lithium transition metal oxide (claims 1-17) that includes an active material, a conductive additive and a binder ([0170-0183]). The lithium transition metal oxide may include a molar ratio of nickel among metal elements excluding lithium included in the lithium metal oxide is 0.8 or more (Table 3, Examples 18-21).
It would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to modify electrode active material in Sikha, or the molar ratio of nickel in the lithium-nickel composite oxide in Sikha, to include a molar ratio of nickel among elements excluding lithium in the metal oxide that is greater than 0.8. One of ordinary skill in the art would be motivated to adjust the molar ratio of nickel in this manner because it “further improv[es] the charge-discharge cycle characteristics over a wide temperature region ranging between room temperature and high temperature (Inagaki, Table 3, ¶[0202]).
Claim 11 is rejected under 35 U.S.C. 103 as being unpatentable over Sikha, as applied to Claim 1, in further view of Gozdz et al (US 2005/0233220), hereinafter Gozdz.
Regarding Claim 11, Sikha teaches all the limitations of Claim 1. Sikha teaches that the electrode active material layers may include conductive materials for providing a conductive path between the particles of the cathodically active materials. The electro-conductive materials may be conductive carbon materials selected from graphite, graphene hard carbon, acetylene black (AB), carbon black (CB), carbon coated silicon, etc. (see [0046]). Sikha does not expressly teach the conductive material (of cathode active material layer) being carbon nanotubes.
Gozdz teaches a lithium battery having the first cathode active material layer and the second active material layer ([0085]) each further including a conductive material (¶[0067], [0087]). Gozdz teaches conductive additives including carbon black, acetylene black, vapor grown fiber carbon and fullerenic carbon nanotubes.
It would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to modify the cathode taught but Sikha to include the carbon nanotubes as the conductive material as taught by Gozdz. One of ordinary skill in the art would have been motivated to include carbon nanotube in the active material because “carbon nanotubes” are examples of exemplary conductive additives detailed in Gozdz (¶[0067], [0073]). One of ordinary skill in the art would recognize that the carbon nanotubes could be used as the conductive material in the electrodes of Sikha.
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure: (i) and (ii).
EP2051319A2 reaches a cathode material for a lithium secondary battery in which a primary particle 1 constituting a secondary particle 2 comprises a particle with a particular size.
JP6424934B1 teaches a positive electrode material for a lithium secondary battery capable of improving the positive electrode density while suppressing exfoliation of a carbonaceous film covering.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to MAXIMILIAN D BAGILEO whose telephone number is (571)270-5460. The examiner can normally be reached Monday-Friday 8:00AM-5:00PM. 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, Mark Ruthkosky can be reached at (571) 272-1291.
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/M.D.B./EXAMINER, ART UNIT 1785
/MARK RUTHKOSKY/SUPERVISORY PATENT EXAMINER, ART UNIT 1785
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